Biochemist
The
Magazine of the Biochemical Society
Vol. 38 No. 6 December 2016
Shine a Light
Contents
The Biochemist Vol. 38 No. 6
Shine a Light
Editorial3
Regulars
Features
Science Communication Competition
Carpe lucem: harnessing organic light sources
for optogenetics
4
4
Andrew Morton, Caroline Murawski and Malte C. Gather
Policy Matters
Painting cells with light
Tackling AMR crisis – a global approach
Gabriele Butkute
8
Santiago Costantino and Claudia L. Kleinman
Novel 3D imaging platform tracks cancer
progression in vivo
12
James McGinty, Paul French and Paul Frankel
Illuminating the cancer-targeting potential
of near-infrared photoimmunotherapy 16
Hisataka Kobayashi
8
Light-activated wound healing and tissue
modification20
24
Michael R. Hamblin
Interviews30
30
Let it glow – Alexander Krichevsky and Ilia Yampolsky
Helen Albert
Historical Feature
Learning Curve
41
42
Is AMR the new climate change?
Anastasia Stefanidou
Book review
45
Cartoon51
Prize Crossword
52
News
Royal Society of Biology News
44
Celebrating Biology Week and taking
life science to Parliament
Irene E. Kochevar and Robert W. Redmond
Photobiomodulation and the brain
– has the light dawned?
38
Cancer: a disease of bad luck, or bad lifestyle?
Jessica Hardy
Meeting reports
46
Society News
CEO Viewpoint
From the Chair
50
51
34
Fatty acids and feminism: Ida Smedley MacLean,
the first woman to Chair the Biochemical Society
Robert Freedman
34
Christmas/New Year closing:
The Biochemical Society and Portland Press offices in London
will be closed for the Christmas/New Year holiday from 24
December 2016 to 3 January 2017 inclusive
Coming
Coming up
up in
in 2017
2017
46
February – Gender Medicine
February
April
– The– Microbiome
Gender Medicine
April – Emerging
June
The Microbiome
Diseases
December 2016 © Biochemical Society 1
Editorial
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The (Christmas) Tree of Knowledge
by Freddie Theodoulou, Science Editor
Picture the scene: the lights are low, mulled wine
is bubbling on the stove and the distant sound of
carols can be heard from rosy-faced singers in the
streets. As you put the finishing touches to the
Christmas tree, what are you thinking? Are you
imagining the joyful responses as your friends and
family open their gifts? Or wondering if fairy lights
are wired in series or in parallel and whether the turkey will defrost in time?
Now, I know you’re supposed to be on holiday but if you’re in a scientific
frame of mind, spare a thought for your Christmas tree, which is not, as you
imagined, the ultimate statement in festive domestic decoration but in fact a
concise lesson in botanical biochemistry!
Let’s start with the choice of tree. If you live in Europe, you’ve probably
purchased a Norway Spruce (Picea abies) or you may have splashed out on
a Noble Fir (Abies procera), because you don’t want to spend the 12 days
of Christmas hoovering up needles. Which brings me to the first lesson:
evergreen plants and the control of leaf abscission. Although decorated
Christmas trees as we think of them were reportedly introduced in the 16th
century by Martin Luther (not a character one would normally associate with
extravagant interior décor), the use of evergreens to symbolise everlasting life
during winter dates back to antiquity. Unlike broad-leaved trees which put
on such a fabulous show of chlorophyll degradation in the Autumn, conifers
have highly reduced leaves (needles), an adaptation to survive winter hardship
and photosynthesise all year round. But as we know, needles do drop off.
Abscission in gymnosperms such as conifers is poorly understood, although
ethylene is one of the usual hormonal suspects. Importantly, needle longevity
is positively related to cold acclimation which brings us neatly to genotype x
environment interactions. By bringing a tree into your cosy, centrally-heated
home, you’ve probably inadvertently broken its winter dormancy, messing
with a delicate balance of hormone signalling (principally gibberellic acid and
abscisic acid), so don’t be too surprised if not only do you have to get the
hoover out, but also that your beloved Weihnachtsbaum fails to survive your
guilt-ridden attempts to plant it out in your garden after Twelfth Night.
More positively, that Noble Fir also has an attractive open habit,
provoking interesting questions about the gravitropic set point branch
angle, which is all about auxin signalling and seriously important for
light interception. Strong branches – good for displaying lots of heavy
ornaments – draw attention to the deposition of lignin, a complex aromatic
polymer derived from the shikimate pathway. Plus, there’s the delicious
Christmassy scent. Here you have terpene synthesis to thank, just one
page in the gloriously diverse catalogue of plant secondary chemistry. And
finally, the lights: never mind electric bulbs, how about a self-lighting tree?
Glow-in-the-dark plants have been on the cards ever since plant biologists
started tinkering with transgenics expressing green florescent protein and
luciferase, but don’t be too hasty: although a number of woody species can
be genetically transformed, it’s by no means easy and a myriad of technical
problems remain to be overcome.
As you’ll hear on page 30, attempts to generate ornamental luminescent
plants are gathering momentum but for now, you’ll have to stick with those
little strings of electric lamps for your tree. Whatever your festive traditions,
be they religious or secular, Happy Holidays!
■
December 2016 © Biochemical Society 3
Shine a Light
Carpe lucem: harnessing organic
light sources for optogenetics
Andrew Morton,
Caroline Murawski and
Malte C. Gather
(University of St Andrews, UK)
With the advent of optogenetics, numerous functions in cells have been rendered responsive to
the experimental delivery of light. The most common implementation of this technique features
neurons genetically modified to express light-sensitive ion channel proteins, which open specifically
in response to pulses of blue light, triggering electrical impulses. Optogenetics has now matured
to a point where in addition to answering fundamental questions about the function of the brain,
scientists are beginning to consider clinical applications. However, further progress in this field will
require new ways of delivering light. One of these involves the use of organic light-emitting diodes
(OLEDs), a display technology increasingly common in modern-day smart phones, for the optical
stimulation of cells.
Making neurons receptive to light
In the last decade, the field of neuroscience has been
transformed by newfound capabilities to control and
monitor neuronal biochemistry with light, using a suite
of techniques collectively referred to as optogenetics.
The unifying feature of these experiments is their
use of either light-sensitive ‘actuator’ proteins (these
drive changes in the cell upon absorption of light,
e.g. a change in membrane voltage) or light-emitting
‘sensor’ proteins (these provide a readout of the cell
state through changes in the intensity or wavelength of
emitted light, e.g. in response to intracellular calcium
concentration). Optogenetics is arguably most widely
identified with the first of these strategies, where
genetic tools to sensitize neuronal tissues to light are
combined with optical technologies to deliver precise
illumination to neurons, with the combined effect of
changing the patterns of electrical signals generated
by neurons. When applied at the animal level, e.g. in
mice or rats, this allows controlling the behaviour of
the animal with light delivered through optical fibres
that are surgically implanted in the brain (Figure 1).
At the heart of many optogenetics experiments is
the light-sensitive actuator protein Channelrhodopsin 2
(ChR2). ChR2 was originally identified as a key protein
required for phototaxis (movement in response to a light
stimulus) in the green alga Chlamydomonas reinhardtii.
Detailed characterization of ChR2 established that it is
a light-gated ion channel, specifically mediating the
flow of ions such as sodium and calcium into cells that
are exposed to blue light (Figure 2a). Fortuitously for
neuroscientists, when the genetic code for ChR2 was
copied into neurons, its response to blue light was
found to trigger neurons to fire the electrical impulses
(action potentials) that ordinarily form the basis of
4 December 2016 © Biochemical Society
communication in the nervous system (Figure 2b)1.
These findings were the prelude to the widespread
adoption of optogenetics by neuroscientists around
the world. Nowadays, neuroscientists have developed
a huge library of channelrhodopsins (ChRs), with
variants capable of either activating or silencing
neurons, in response to light of wavelengths all along
the visible spectrum, acting on timescales extending
from milliseconds to hours.
The combined power of optogenetics emerges
from the ability to target cells of interest based on
their genetic make-up, plus the comparative ease
with which individual cells can be targeted with light.
Genetic information for ChRs can be safely packaged
inside viral particles, which neurons internalize
and dutifully process to produce the light-sensitive
proteins. In this way, tissues in live animals can be
genetically modified to express ChRs where they
are required. When genetically modifying cells to
produce ChRs, their genetic code can be delivered
alongside sequences that encode fluorescent
proteins, thus allowing the easy identification of
ChR-producing cells by fluorescence microscopy
before delivering excitatory pulses of blue light.
Likewise, they can be linked to sequences that
limit the production of ChRs to certain cell types,
or tied to the action of specific enzymes, chemical
compounds or other factors. These properties
can be combined like a programming language,
enabling complex experiments. For instance, ChRs
could be produced only by neurons in a particular
circuit in the mouse brain that is activated when
the animal performs a specific task. Subsequently
reactivating the same circuit with blue light could
make the animal recapitulate the learned behaviour.
Using such strategies, researchers have identified
Shine a Light
assemblies of neurons in the brain that are involved
in processing information during certain activities.
Delivering optical stimuli to neurons
In parallel to these innovations in molecular, cellular
and behavioural biology, the widespread adoption of
optogenetics has also driven technological advances in
optics that increase the specificity with which light can be
delivered to individual neurons. For basic experiments,
on cell cultures, for example, the same light sources
used to illuminate samples in fluorescence microscopes
are often repurposed to deliver optical stimulation for
optogenetics. Light stimulation in optogenetics should
usually be delivered as sequences of pulses with a length
in the 1 to 10 millisecond range in order to emulate
naturally occurring patterns of electrical activity in
neural circuits. In addition, the spectrum of light should
match the absorption of the used ChR and enough light
needs to be delivered so that a sufficient number of
ChRs per neuron are opened and electrical impulses are
triggered. Light-emitting diodes (LEDs) and laser diodes
meet all the above requirements and are indeed widely
used in optogenetics.
Another challenge is how to direct light to certain
cells or groups of cells without exposing neighbouring
cells. Such targeted light delivery can in principle
provide a massive improvement in the specificity
with which cells can be activated. Genetically, one can
programme certain types of neurons to produce ChR,
but optically one could address individual neurons
(or at least very small, localized groups of neurons).
Available options to achieve this involve the use of
sophisticated confocal or two-photon microscopes
which use complex arrangements of mirrors and lenses
to shape and distribute light provided by pulsed lasers.
However, due to the bulky size of these microscopes,
they are usually limited to studies on tissue explants or
on head-fixed animals. In addition, microscopes deliver
light from the outside and so can only reach a few
tenths of a millimetre into the brain, which limits their
usefulness, in particular, for future clinical use. Scientists
have therefore turned to inserting optical fibres, fine
bundles of fibres or other miniaturized optics into the
brain to deliver light to deeper brain regions2. While this
has yielded exciting results, it is fundamentally difficult
to miniaturize these devices sufficiently to prevent
damage to the surrounding brain tissue. Researchers
have now developed arrays of microneedles decorated
with tiny LEDs along the needle shaft. These so-called
‘LED shanks’ can be extremely thin and have enabled
optogenetic control of free-moving awake mice3,4. The
vast complexity of the brain means that ideally one will
have hundreds to thousands of individually addressable
LEDs on each shank, with each LED being small enough
Figure 1. Optogenetics allows the manipulation of animal behaviour through light-mediated
activation of neurons in the brain. This facilitates a range of novel and controlled neuroscience
experiments which use light to better understand the function of the brain. (Reprinted with
permission, Society for Neuroscience 2014, from M.J. Robinson, J. Neurosci. 34, 16567 (2014).)
Figure 2. (a) Schematic of the ion-channel protein ChR2 which opens in response to irradiation
with blue light. (b) When embedded into the membrane of a neuron, ions flowing in through
the ChR2 lead to a change in membrane potential that can trigger the neuron to fire an action
potential. (Reprinted with permission, Nature Publishing Group 2011, from E. Pastrana, Nat.
Meth. 8, 24 (2011).)
to address, at most, a handful of neurons. Controlling such a vast number of LEDs
without an unmanageable number of connections and wires would require placing the
LEDs directly onto a small electronic microchip. Unfortunately, however, the presently
available LED technology, which is based on gallium nitride, is not directly amenable
to integration with today’s mostly silicon-based microchip technology (ultimately this
is due to the crystal lattices of gallium nitride and silicon having different dimensions).
This incompatibility between microchips and LEDs is one of the reasons we recently
began to repurpose a display technology which is used in many modern-day smart
phones for the delivery of light in optogenetics experiments.
Repurposing mobile phone displays for optogenetics
Organic light-emitting diodes are light sources based on plastic-type hydrocarbons
containing large π-conjugated electron systems. In an OLED, thin layers of different
organic compounds are sandwiched between two thin electrodes, at least one of which
December 2016 © Biochemical Society 5
Shine a Light
is semi-transparent (Figure 3). When an electrical current is passed through this thin
stack – the total thickness is typically less than 200 nm – light of a specific colour
is emitted. Although OLEDs were first described over two decades ago, it is only in
recent years that refinements to fabrication processes and device designs have seen
OLEDs more routinely being deployed in everyday devices. Today, they form the lightemitting structure in displays of mobile phones – and for the wealthier among us they
are increasingly used in TV displays – and due to their high efficiency they may well
become light sources of choice for general illumination in the future.
a
b
Figure 3. (a) Schematic structure of an organic light-emitting diode (OLED) consisting of multiple
vertically stacked layers of plastic-type organic materials sandwiched between two electrodes.
When passing a current through this stack, the organic material efficiently generates light of a
specific colour. (b) When deposited on a flexible substrate, OLEDs can be bent and flexed and
could thus be made to conform to the surface of the brain. (Credit: IAPP, Dresden.)
a
b
Figure 4. Use of an array containing many thousands of individual OLEDs for optogenetic
control. (a) Picture of an OLED array embedded into a Petri dish (left) and microscope image of
the array in operation, with individual OLEDs programmed to show the logo of the University
of St Andrews (right, reprinted with permission, Wiley-VCH 2015, from Ref. 5). (b) Response of a
cell producing ChR to direct light exposure from OLEDs underneath (top) versus no response to
light from OLEDs next to the cell (bottom). (Reprinted with permission, AAAS 2016, from Ref. 6.)
6 December 2016 © Biochemical Society
The organic materials used in OLEDs share many
properties with inorganic semiconductors such as silicon
or gallium nitride. However, in contrast to these, they are
amorphous rather than crystalline which means they are
mechanically flexible and can be readily deposited on a
large variety of different substrates, including siliconbased microchips. This makes them a prime candidate
for microchip-based OLED shanks that feature a large
number of individually addressable light sources and
may also allow the design of conformable and bendable
implants that would be less disruptive to brain tissue.
Our efforts to demonstrate the usefulness of
OLEDs as light sources for optogenetics have somewhat
mirrored the path followed by biologists when they first
developed optogenetics. The first demonstration that
OLEDs can control light-mediated responses in cells
used the green Chlamydomonas reinhardtiialga alga,
from which ChR2 was originally extracted. We placed
these cells onto a dense array of OLEDs that contained
over 100,000 individually addressable OLEDs and found
that the alga cells swam towards whichever OLEDs on
the array were turned on5. When we first succeeded in
making this happen, we joked that this was a bit like
having cells watch TV!
Next, we demonstrated that cells can be grown
directly on an OLED array. This time, we used cells that
are not normally light sensitive and that were genetically
programmed to produce ChRs. Because of the small
dimensions of each OLED and the short distance between
OLEDs and cells, this indeed allowed us to address the
ChRs in individual cells by turning on the OLEDs just
underneath each cell6. Figure 4 shows pictures of the
used OLED arrays and data from a measurement that
compares the response of cells with light from OLEDs
located at different distances from the cell.
As the OLED technology was originally developed
for TVs and displays, the brightness they provide is
normally in a range suitable for human vision. However,
our eyes are considerably more sensitive to light than
cells that are rendered light sensitive via optogenetics;
in fact, the light intensity required for an optogenetics
experiment is 100–1000-fold higher than the brightness
of a typical computer screen or TV. We have recently
seen that this requirement can be accommodated
by resorting to special OLED designs that make use
of principles similar to the doping used to adjust the
conductivity of conventional semiconductors. With
such devices, it is possible to control the motion of fruit
fly larvae programmed to produce ChR in their motor
neurons and this represents the first demonstration
of OLED-mediated optogenetic control for a multicellular organism7.
Despite these promising initial results on the use of
OLEDs for optogenetics, further research is required for
the potential of OLEDs to be fully exploited. Specifically,
Shine a Light
customized microchips in shank format that can operate
OLEDs in pulsed mode and at high brightness will
need to be developed. Besides further increasing OLED
brightness and efficiency, the possibility of designing
OLEDs that are mechanically flexible should be exploited
for minimally invasive bio-implants that conform to the
surface of the brain. Finally, in particular for chronic
implants or for any future clinical use – where OLEDs
would be left in the brain for weeks, months or even
years – their durability needs to be enhanced by better
protection against the ingress of water.
Devices of the future
Because OLEDs can effectively be printed on any
scale, they lend themselves well to being integrated
as light sources in many different types of devices. In
lab-based settings, this may enable their integration as
a light source into multi-well plates to facilitate highthroughput screening applications, the development
of OLED shanks or flexible OLED sheets. Although
further advances in light-delivery technologies and
optogenetics as a whole will undoubtedly be central
to many future insights into the functioning of the
nervous system, the question remains, if and how such
efforts can and should be leveraged to benefit human
health directly. For optogenetics to be implemented in
therapeutic efforts, one of the main questions relates to
the viability and safety of sensitizing human tissues to
light, e.g. via gene therapy. One US-based company is
currently carrying out the first clinical trials in humans:
for patients suffering from certain types of blindness,
ChRs are being virally delivered to the retina, with the
aim of restoring some components of light sensitivity
in an otherwise degenerated visual system. There are
also plans for a clinical trial to use optogenetics for
treating patients suffering from chronic pain. Other
ideas include the development of optogenetic cochlear
implants which could surpass their electronic analogues
in terms of frequency range covered or the design of
optical pacemakers. While efforts to restore vision
through optogenetics may ultimately lead to solutions
not requiring artificial light-delivery systems, the success
of many other optogenetic-based neuronal interfaces
will likely require further innovation on the device level.
Like many other new technologies, optogenetics,
and in particular its clinical application, triggers
ethical questions about whether we should develop
a technology that could be used to alter, augment or
even enhance the function of the human brain. And
as with other technologies, there are no easy answers.
Is it ethical to develop or to refrain from developing a
technology that would improve the quality of life for
patients with severely disabling neurological diseases?
Where should we draw the line between a medical
treatment and a cybernetic enhancement that could
provide unfair cognitive advantages – possibly only
to those of high social status – or that may affect our
judgement or values? Such questions are of the utmost
importance and they need to be posed again and again as
the technology develops. However, as with other fields of
science, categorically banning research that may enable
us to understand our own mind is probably a poor
choice. From our perspective on optogenetics research,
ethical questions are being taken very seriously by the
scientists involved so that we are carefully optimistic that
the benefits of these new tools for neuroscience research
and neuromedicine will greatly outweigh their risks.
■
Andrew Morton is a research fellow in the
group of Professor Gather. A neurobiologist
with interests in the functional properties
of synapses and neuronal networks, he
is currently working on simultaneous
optogenetic activation and optical
reporting of neural activity. Email: [email protected]
Caroline Murawski is a Marie Curie
Fellow in the group of Professor Gather.
She received her PhD working on highbrightness organic light-emitting diodes,
which she is now further developing
for implementation into optogenetics.
Email: [email protected]
Malte C. Gather is a Professor in the
SUPA School of Physics and Astronomy
at the University of St Andrews. He leads
the Soft Matter Photonics group which
develops microphotonic tools for the life
sciences. Email: [email protected]
References
1. Boyden, E.S., Zhang, F. Bamberg, E., Nagel, G. and
Deisserothm, K. (2005) Nat. Neurosci. 8, 1263
2. Abaya, T.V.F., Blair, S., Tathireddy, P., Rieth, L. and
Solzbacher, F. (2012) Biomed. Opt. Express 3, 3087
3. Il Park, S. Brenner, D.S., Shin, G., et al. (2015) Nat.
Biotechnol. 33, 1280
4. Scharf, R., Tsunematsu, T., McAlinden, N., Dawson, M.D.,
Sakata, S. and Mathieson, K. (2016) Sci. Rep. 6, 28381
5. Steude, A. Jahnel, M., Thomschke, M., Schober, M. and
Gather, M.C. (2015) Adv. Mater. 27, 7657
6. Steude, A., Witts, E.C., Miles, G.B. and Gather, M.C.
(2016) Sci. Adv. 2, e1600061
7. Morton, A., Murawski, C., Pulver, S.R. and Gather,
M.C. (2016) Sci. Rep. 6, 31117
December 2016 © Biochemical Society 7
Shine a Light
Painting cells
with light
Santiago Costantino (Université de Montréal, Canada) and Claudia L. Kleinman (McGill University, Canada)
Humans perceive, interpret and remember the world based mainly on sight. Images are at the basis
of our understanding and our behaviour, and we mould the world using vision as our most important
sense. Indeed, two of the technological advances that have revolutionized the way we understand the
universe are the telescope and the microscope, which act by extending the power of human vision.
They magnify and improve image resolution of immense distant bodies and of miniscule objects at
the tip of our fingers.
As opposed to the pioneers that observed and
discovered details of celestial objects, who are
remembered as scientific heroes in the history books,
the discoverers of the microscopic cosmos are perhaps
less well known, but equally noteworthy. The work of
Hooke and van Leeuwenhoek, for example, exposed
a complex microscopic universe with structure
and order, such as in the anatomy of insects or the
honeycomb structure of cells in cork, and revealed
the existence of bacteria, protozoa and sperm cells
in human semen. These findings triggered a major
conceptual shift, that later led to debunking the idea
of spontaneous generation and became the foundation
of our current understanding of life1.
The resolution of the early compound microscopes
is more or less equivalent to what we currently use
in the lab. However, beyond correction of optical
aberrations and improved numerical apertures, it
was the manipulation of the observed material and
the development of stains and contrast agents that
provided the field with vital tools to investigate
cellular organization and physiology. In particular, the
need to detect and identify molecules in their cellular
context has driven the development of reagents to
tag proteins in such a way that they became visible
under the microscope. The advent of fluorophores as
probes to detect antibodies, proteins and amino acids
radically changed the study of molecular structure and
interactions. This transformation, triggered by the use
of fluorescence microscopy in the lab, is due, in part,
to the fact that it is a visual technology. The ability
to use fluorescence to literally see labelled molecules
creates a fundamental rapport with microscopy,
allowing a better understanding of cellular biology by
watching cells and molecules in action.
8 December 2016 © Biochemical Society
From molecular to cellular tags
Although the first reports of fluorescent substances
date back to the XVI century, the first fluorescence
microscope appeared in 1911, only 100 years ago. The
development of fluorescein-labelled antibodies by
Albert Coons in the early 1940s was seminal for the
development of quantitative microscopy. These tags
have been used for decades to image macromolecules,
well below the diffraction limit, using visible light. In
particular, they are widely used to identify specific
cells, based on the expression of known markers. An
alternative approach involves the transfection of genes
encoding for fluorescent proteins under the control
of specific promoters, making cells light up only
when the promoter becomes active, or fluorescent
proteins fused to cellular proteins, allowing the study
of protein localization and dynamics in living cells.
These methods are now central to molecular and
cellular biology.
An important limitation of most methods for
labelling cells with fluorescence, however, is that
they rely on biochemical characteristics that are
common to an ensemble of cells within a sample.
These approaches are not suited for targeting specific
cells among a large population of the same type, and
their efficiencies and specificities are dependent on
stochastic events and molecular affinity properties
that frequently yield a sub-optimal fraction of
correctly labelled cells. Nevertheless, biological
processes are often triggered by specific individual
cells within large ensembles, and there is a need to
identify and study these particular cells. Such is the
case in processes relevant to development, immune
response, stem cell biology, neurobiology and
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CLaP enables instant, specific tagging of individual cells. Cells are incubated with biotin-4fluorescein (B4F) which is photobleached and crosslinked to the plasma membrane using
laser beam. After rinsing, only illuminated cells retain biotin molecules and are revealed
with fluorescent streptavidin. Here we show confluent green MDCK cells in culture with
one CLaP-tagged cell using Alexa-647-Streptavidin. Reproduced with permission from
Nature Communications.
December 2016 © Biochemical Society 9
Shine a Light
Reactive species induced by photobleaching B4F also create transient adhesions between the cell basal membranes and the substrate, because trypsin only
detaches cells that have not been illuminated. As an illustration, we show a bright-field, contrast-enhanced image of a miniature world map created adhering
ARPE-19 cells. Reproduced with permission from Nature Communications.
cancer, where cellular heterogeneity plays a major
role. Furthermore, the local microenvironment,
cellular cross-talk and spatio-temporal dynamics all
induce context-specific molecular changes for which
no marker is available. In many cases, however, these
molecular changes do have a visual correlate.
Thus, it is often critical to selectively label cells
based on traits that are readily identified under the
microscope: movement, shape, size and position.
Electroporation is the more traditional way to
achieve single-cell labelling, which involves the use
of an electrode that produces a high-voltage pulse
train inducing the formation of transient pores
in the plasma membrane2. Dyes and molecules in
the media can then penetrate cells through these
transient pores to allow labelling, and also to deliver
drugs and molecules. More recently, photoactivable
and photoswitchable fluorescent proteins, which
change their emission wavelengths or their yields
upon illumination3, have been introduced to this
effect. They are typically transfected into the cells
for ubiquitous expression, and laser irradiation over
the desired set of cells induces selective fluorescence
changes. Illuminated cells will switch off or on, or
10 December 2016 © Biochemical Society
change from red to green, and these changes can
be performed with sub-cellular resolution, so that
single cells or vesicles can be identified and tracked.
Cell labelling via photobleaching (CLaP) has
recently been presented as a non-invasive method to
achieve instantaneous tagging of single cells without
requiring transfection or membrane permeabilization4.
CLaP tethers biotin molecules to the plasma membrane
of living cells using a low-intensity light beam. Biotin-4fluorescein (B4F) is added to the culture medium and a
laser, tuned near the absorption peak of the dye, is then
focused on individual cells of choice. This generates free
radicals in close proximity to the plasma membrane
that lead to biotin crosslinking. Since the entire process
occurs in a small region outside the cell, phototoxicity
is negligible. Upon addition of streptavidin conjugates
to the culture medium, only those cells that have
been irradiated will bind streptavidin conjugates. By
choosing different types of streptavidin conjugates,
cells can be labelled with fluorescence, electron-dense
particles and potentially several other labels with
diverse physico-chemical properties.
With this approach it now becomes possible to
tag individual cells with a laser, based on a wide array
Shine a Light
of criteria chosen by the experimenter at the time of
observation. Tags are not restricted to fluorescent
modalities and cells labelled this way can be tracked
for several days, isolated and individually studied. The
approach is simple, low-cost and uses off-the-shelf
reagents based on biotin–streptavidin conjugates. In
fact, it may be implemented by any researcher with
access to a standard confocal microscope.
From cellular tags to molecular profiles
The engineering needs for single-cell research are mostly
driven by novel next-generation sequencing technologies
and personalized medicine initiatives, where the
analysis of cell sub-populations can potentially be used
to determine appropriate investigative and therapeutic
strategies. Indeed, fast and cost-efficient methods for
identifying and isolating individual cells from large
heterogeneous cell ensembles remain a technological
challenge. But the field holds, nonetheless, great promise,
and constitutes a very active area of research.
A disease area that may be particularly impacted
by these novel technologies is cancer, where a few rare
cells, hidden within millions, drive disease progression
and therapeutic resistance5. Single-cell sequencing has
been used to define cell lineages, identify cancer cell
sub-populations, infer tumour evolution and, in a more
clinically applied perspective, to highlight mechanisms
of therapeutic resistance. With the advent of sequencing
technologies, which allow molecular profiling for a
cost that has been, so far, constantly decreasing, the
field shifted towards the generation of large databases
of genome-wide mutational and transcriptional
information. This burgeoning field is now combining
high-throughput sequencing approaches with imaging
modalities, thereby correlating our observations with
genomic information, cell by cell.
A few new technologies have been proposed,
besides CLaP, to sequence cells chosen by observation
or preserving spatial information. They either add
labels to cells in a microscopy platform, consisting of
tracers that can be revealed later in the pipeline4,6, or
change the standard protocols for sequencing in situ7,8.
A few challenges related to the throughput, degree of
automation and characterization of biases will need
to be solved before they become widely used tools
in biomedical applications. The field is moving at an
incredibly fast pace as the tools become accessible to
fundamental and clinical researchers alike. The marriage
of microscopy and single-cell sequencing combines
our visual interpretation of the cellular realm with
quantitative, genome-wide, molecular data, promising
to transform our comprehension of life.
■
Santiago Costantino received his PhD
in ultrafast lasers from the Physics
Department of the University of
Buenos Aires, under the supervision
of Oscar E. Martínez, in 2003. He
moved to Canada for his postdoctoral
training in microscopy and neuroscience at McGill University.
He established his biophotonics lab at the MaisonneuveRosemont Hospital Research Center, University of Montreal,
in 2007. He is now an Associate Professor and his current
research spans cellular microengineering, image analysis and
the development of medical tools for vision health. Email:
[email protected]
Claudia L. Kleinman is an Assistant
Professor in the Human Genetics
Department and full time investigator
at the Lady Davis Research Institute,
McGill University. She holds a PhD in
Bioinformatics from the Université
de Montreal, and has an interdisciplinary training that
combines molecular biology, computer science, statistics and
evolutionary biology. Her research focuses on elucidating
molecular mechanisms of disease, particularly cancer and
brain disorders, using large-scale data analysis and genomic
technologies. Email: [email protected]
References
1
2
3
4
Boorstin, D.J. (1988) The Discoverers, Random House,
Toronto, Canada)
Wang, M., Orwar, O., Olofsson, J. and Weber, S.G. (2010) Single-cell
electroporation. Anal. Bioanal. Chem. 397, 3235–3248, doi:10.1007/
s00216-010-3744-2
Zhou, X.X. and Lin, M. Z. (2013) Photoswitchable fluorescent proteins:
ten years of colorful chemistry and exciting applications. Curr. Opin.
Chem. Biol. 17, 682–690, doi:10.1016/j.cbpa.2013.05.031
Binan, L., Mazzaferri, J., Choquet, K., et al. (2016) Live single-cell laser tag.
Nat. Commun. 7, 11636, doi:10.1038/ncomms11636
5
6
7
8
Meacham, C.E. and Morrison, S.J. (2013) Tumour heterogeneity and
cancer cell plasticity. Nature 501, 328–337, doi:10.1038/nature12624
Lovatt, D., Ruble, B.K., Lee J., et al. (2014) Transcriptome in vivo analysis
(TIVA) of spatially defined single cells in live tissue. Nature Methods 11,
190–196, doi:10.1038/nmeth.2804
Coskun, A.F. and Cai, L. (2016) Dense transcript profiling in single cells by image
correlation decoding. Nature Methods 13, 657–660, doi:10.1038/nmeth.3895
Lee, J.H., Daugharthy, E.R., Scheiman, J., et al. (2015) Fluorescent in situ
sequencing (FISSEQ) of RNA for gene expression profiling in intact cells
and tissues. Nat. Protoc. 10, 442–458, doi:10.1038/nprot.2014.191
December 2016 © Biochemical Society 11
Shine a Light
Novel 3D imaging
platform tracks cancer
progression in vivo
James McGinty,
Paul French (Imperial
College London, UK) and
Paul Frankel (University
College London, UK))
Optical imaging underpins biomedical research in many respects and recent decades have seen spectacular
advances, particularly in fluorescence imaging where genetic engineering approaches to labelling have
been combined with new light sources, detectors and data analysis techniques to provide capabilities like
super-resolution beyond the diffraction limit, exquisite spectroscopic contrast for molecular readouts and
high-speed image capture for in vivo and high-throughput applications. However, the main impact of such
advanced instrumentation and data analysis has been to provide unprecedented quantitative 2D and
3D information concerning samples compatible with microscopy where volumes of less than 1 mm3 are
typically imaged in a single ‘acquisition’. The ability to view and measure cellular processes and signalling
pathways in live cells has been a significant advance for biomedical research and drug discovery. However,
for conventional microscope-based assays and experiments, the samples typically comprise thin layers of
cells that are not experiencing the same signals that they would in a 3D tissue context and any findings
may not directly translate to live organisms. It is desirable to study disease processes in live intact organisms
that can provide appropriate physiological complexity. For cancer studies, recent research from our group
shows that optical tomography can be used to directly monitor in vivo changes in tumour growth and
vascular development in a zebrafish cancer model over time. This technique not only improves the value of
the collected data, but if used on a wider scale should result in a reduction in the number of animals used
in biomedical research.
The rise of fluorescent proteins
The development of target-specific labelling strategies
– particularly the ability to express genetically encoded
fluorescent proteins in live cells1 – has enabled cellular
processes and signalling pathways to be visualized and
quantified. For convenience, such studies are usually
undertaken in thin cell cultures (typically on microscope
coverslips), but there is an increasing appreciation that
the behaviours observed in 2D cell mono-cultures cannot
necessarily be directly translated into an in vivo context2. This
is particularly important for understanding disease processes
and determining the efficacy, safety and off-target effects of
therapies in the drug discovery pipeline. Subsequently, there
has been a drive to develop imaging techniques and assays
to study disease mechanisms in more realistic physiological
contexts. Ideally, preclinical studies should be undertaken
in disease models that are as close to humans as possible.
However, this aspiration is set against the ability to genetically
manipulate the organisms and considerations of accessibility
for optical and other readouts.
Murine models are widely used because of their
genetic tractability and physiological similarity to humans
but they are not optically accessible and the gold standard
12 December 2016 © Biochemical Society
for preclinical readouts of disease remains histopathology,
where the animal is sacrificed and tissue sections produced
from regions of interest are stained and imaged at high
resolution using optical microscopy. Unfortunately, this
can only be performed at a single timepoint per animal and,
because only a finite number of sections can be produced,
the volumetric sampling may miss important features in
heterogeneous tissue. Furthermore, the whole process is
time-consuming, requiring significant manual processing
and the small fields of view typical of microscopy must
be stitched together to map significant fractions of the
animal. Fluorescence microscopy can be implemented
directly in vivo but the limited field of view and the
strong absorption and optical scattering experienced by
light in tissue limits the range of physiological contexts
that can be accessed. Furthermore, the process usually
involves invasive procedures with animals that must be
euthanized. Currently therefore, whole-animal preclinical
imaging in mammals mainly relies on modalities like
X-ray computed tomography (CT), magnetic resonance
imaging and positron emission tomography, which
cannot realize the high (cellular) resolution or molecular
contrast and specificity that are available with fluorescence
imaging. Fluorescence imaging in intact mice can be
Shine a Light
realized using fluorescence molecular tomography
and similar techniques3 that essentially consider the
statistical properties of light transport in biological tissue
and usually rely on simplifying assumptions to analyse
signals based on scattered photons, such as the diffusion
approximation. These approaches can reconstruct maps
of the tissue’s optical properties using inverse scattering
techniques, but produce images with spatial resolution
limited to greater than 1 mm in mice – significantly
degraded compared with the optical diffraction limit.
Potential of in vivo optical imaging
Higher resolution in vivo optical imaging is possible in
smaller transparent organisms such as the nematode
worm (Caenorhabditis elegans), fruit fly (Drosophila
melanogaster) and larvae of fish such as the zebrafish
embryo (Danio rerio), that typically entail imaging through
a path of less than 1 mm and for which the usual range
of genetic tools are available. This regime is described
as ‘mesoscopic’ imaging and is a very active field that
encompasses techniques such as optical projection
tomography (OPT)4 and light sheet microscopy5, which
can provide high-speed, high-resolution 3D imaging for
volumes up to ~1 mm in size. While nematodes and flies
are non-vertebrates, zebrafish physiology is closer to that of
humans and zebrafish larvae are finding increasing interest
as a convenient disease model for biomedical research
and drug discovery6. However, limiting the application
of zebrafish studies to embryos also limits the research
opportunities, as the larvae are physiologically immature
and do not possess fully developed body systems, such as
vasculature and immune systems. In this respect, studies
using adult zebrafish models are more desirable. However,
adult zebrafish reach up to ~1 cm in diameter and ~5 cm
in length and so are too large for whole-body imaging in
a microscope. Furthermore, whereas zebrafish larvae can
be kept optically clear, wild-type zebrafish are pigmented
– resulting in significant optical scattering and absorption.
The use of zebrafish as in vivo models to study cancer
is increasing as they possess various advantages over their
mouse counterparts such as easier genetic manipulation
and a broader range of imaging opportunities with
transparent lines. In relation to translational research, the
histological appearance and gene expression profiles of
tumours have been shown to be highly conserved between
humans and zebrafish7. Such histological and genetic
similarities suggest that pathogenesis is similar between
these species, thus validating the use of these organisms as
faithful cancer models.
We have developed a whole-animal 3D optical imaging
platform that takes advantage of non-pigmented zebrafish
mutants, of which the adults are sufficiently transparent
to permit optical readouts8,9,10. This platform is based on
OPT of adult fish that are immobilized under anaesthetic
Figure 1. Schematic of an OPT system.
and utilizes a compressive sensing approach10 to minimize
the data acquisition time and therefore enables the fish to
be recovered and reimaged over an extended time course
for longitudinal studies11.
Optical projection tomography
of live zebrafish
OPT can be described as the optical equivalent of X-ray
CT. It entails rotating the sample and acquiring a series
of wide-field fluorescence images at a number of different
angular projections, as illustrated in Figure 1. The sample
is suspended from a rotation stage in a chamber of
refractive index matching fluid (for in vivo imaging this
is just water). Appropriate excitation light illuminates the
sample (in wide-field) to generate fluorescence, which is
imaged onto a camera using an imaging system with an
aperture. The radius of this aperture is set such that the
front half of the sample is imaged ‘in focus’, providing a
projection image. The sample is then sequentially rotated
and imaged at a range of angles until it has stepped
through a full 360° rotation.
Following the standard formalism of CT12, each pixel
in the wide-field fluorescence image can be considered as
the sum of the fluorescence signal along a ‘line-of-sight’
perpendicular to the camera sensor – or in other words, the
2D wide-field image is a ‘projection’ of the 3D fluorescent
volume. This is analogous to an X-ray image containing
information about the absorption of a 3D sample along
‘lines-of-sight’ and the acquisition and reconstruction
procedure are equivalent to X-ray CT: the 3D fluorescence
image is reconstructed from the set of angular projection
images using filtered backprojection (FBP). An important
assumption for FBP, as in X-ray CT, is that the detected light
has travelled in straight lines from the sample to the detector,
December 2016 © Biochemical Society 13
Shine a Light
Figure 2. (a) segmented reconstruction of in vivo OPT data with tumour (green) and vasculature (red), and plots showing (b) tumour volume and (c) %
tumour vascularization determined from the in vivo OPT data and (d) measurements based on ex vivo immunohistochemistry. Each point is an individual
fish. Scale bar 5 mm.
therefore the light should not have been scattered and the
sample being imaged should lie within the depth of field of
the imaging lens. The requirement for the sample to be nonscattering means that OPT has typically been used to image
‘chemically cleared’ samples4, for which water in the sample
has been replaced by a liquid of higher refractive index in
order to minimize the refractive index variation between
different tissue components and therefore to minimize
optical scattering. Since this chemical treatment can only be
performed ex vivo on fixed samples, it is necessary to realize
in vivo OPT with transparent organisms. As discussed above,
we have established that non-pigmented adult zebrafish
mutations are sufficiently transparent to enable OPT to be
performed in vivo on anaesthetized samples.
Imaging tumour growth
and vascularization
Figure 2 illustrates how whole-body OPT of a zebrafish
cancer model can enable tumour growth and vasculature
to be studied. We imaged ‘transparent’ zebrafish in which
the growth of a liver tumour expressing green fluorescence
protein could be prompted by exposure to a chemical
inducer10. This disease model also expresses mCherry
fluorescence protein in the endothelial cells of the blood
vessels. By mapping the 3D distribution of green and
red fluorescence in these fish through in vivo OPT, we
could measure tumour and vasculature development in
a minimally invasive way, requiring less than 10 minutes
to acquire the data in both red and green fluorescence
channels. To acquire the image data in such a short time
14 December 2016 © Biochemical Society
we applied a compressed sensing approach where we
acquired only 64 angular projections for each OPT data
set (rather than the ~600 projections required for lossless
reconstruction using standard FBP) and reconstructed
the images iteratively as described in 10.
To validate our platform, we performed a crosssectional study of tumour progression over 3 weeks
followed by 1 week without inducer, which results in
tumour regression. Typical segmented reconstructed
tomographic images acquired over this time course of
tumour (green) and vasculature (red) are shown in Figure
2(a). Tumour and segmented vasculature 3D images were
then analysed in terms of tumour volume and vessel
properties (e.g. branching, average vessel length, tortuosity,
etc.11). Figure 2(b,c) show quantitative measurements of
tumour progression and vascularization derived from
the 3D reconstructions of the in vivo OPT acquired
data. Figure 2(d) shows the corresponding changes in
vascularization measured using immunohistochemistry.
Importantly, the similarities observed in the comparative
analysis of OPT vs immunohistochemistry of the tumour
vasculature validates our approach.
Since OPT data acquisition is non-invasive, it does
not require the zebrafish to be sacrificed and so repeated
measurements can be undertaken for longitudinal
studies. Importantly, the OPT data is whole-body
and not limited to discrete spatial sampling, unlike
histopathology. This means that OPT could potentially
readout non-local effects/structures like metastasis,
which would require significantly more pathological
analysis and/or would otherwise be missed.
Shine a Light
Future directions
This initial study demonstrated that in vivo OPT can
be used to monitor vascular changes associated with
tumour growth/recession in live adult zebrafish with
similar quantitative readouts to those obtained from
histopathological assessment. Unlike histopathology,
however, OPT interrogates the whole zebrafish and
permits longitudinal studies. This will lead to improved
data consistency by reducing the impact of biological
variability between different fish. In turn, this can lead
to a reduction in the total number of zebrafish required
to produce statistically significant readouts for assays of
cancer progression and the response to potential therapies.
Our study11 was limited to fluorescence intensity
imaging but more sophisticated fluorescence imaging
techniques, such as spectrally and lifetime-resolved
fluorescence imaging applied in microscopy, can also be
implemented with OPT. For example, we have demonstrated
that Fluorescence Lifetime Imaging Microscopy (FLIM)
OPT can be applied to provide 3D quantitative readouts
of genetically expressed Förster resonance energy transfer
(FRET) biosensors, specifically mapping radiation-induced
apoptosis in zebrafish embryos using FLIM OPT of a FRET
biosensor for caspase 313.
We believe that this work illustrates how the
combination of semi-transparent model organisms that
can be genetically manipulated with whole-body 3D
imaging techniques can be used for both fundamental
biology and drug discovery and efficacy studies. It
can take advantage of the significant developments
made in fluorescent reporters developed for cellular
assays, transferring them to in vivo assays, including
longitudinal studies with the potential to improve data
consistency and reduce the numbers of animals required
for biomedical research and drug discovery.
■
This work was primarily supported by the UK Medical
Research Council with contributions from the British Heart
Foundation, the UK Engineering and Physical Sciences
Research Council, the National Institute for Health
Research, the Brain Tumour Charity (UK), AstraZeneca and
Magnus Life Science.
James McGinty is a Senior Lecturer in
the Department of Physics at Imperial
College London. His initial research
career concentrated on developing
instrumentation and analysis software for
time-resolved fluorescence imaging with
particular emphasis on fast acquisition rates. His current research
concentrates on translating and applying quantitative microscopy
techniques to more challenging and/or physiologically relevant 3D
samples, including cm-sized resected tissue volumes, zebrafish and
mice. Maintaining the same optical contrast mechanism across the
imaging scales should lead to improved correlation between initial
in vitro cell and subsequent in vivo measurements.
Paul French is Professor of Physics and
former Head of the Photonics Group at
Imperial College London. He has also
worked at the University of New Mexico
and AT&T Bell Laboratories. His research
has evolved from ultrafast dye and
solid-state laser physics to biomedical optics with a particular
emphasis on FLIM for applications in molecular cell biology,
drug discovery and clinical diagnosis. His current portfolio
includes the development and application of multidimensional
fluorescence imaging technology for microscopy, endoscopy
and tomography.
Dr Paul Frankel is a Group Leader in the
Division of Medicine at University College
London and a consultant for Magnus Life
Sciences. His research specialises in the
development of novel molecular targeted
agents for the treatment of cancer. Dr
Frankel received a PhD in Molecular Biology from the City
University of New York Hunter College, specialising in cancer cell
signalling. He then moved to the UK to undertake post-doctoral
studies in the Laboratory of Professor Chris Marshall FRS at
The Institute of Cance Research. Dr Frankel’s group combine
molecular analysis of cell signalling required for cancer cell
motility with state-of-the-art 3D imaging technologies and are
working on multiple drug discovery activities.
References
1. Giepmans, B.N.G., Adams, S.R., Ellisman, M.H., et al. (2006) Sci. 312,
217–224
2. Abbott, A. (2003) Nat. 424, 870–872
3. Leblond, F., Davis, S.C., Valdes, P.A., et al. (2010) J. Photochem. Photobiol.
B. Biol. 98, 77–94
4. Sharpe, J., Ahlgren, U., Perry, P., et al. (2002) Sci. 296, 541–545
5. Huisken, J., Swoger, J., Del Bene, F., et al. (2004) Sci. 305, 1007–1009
6. Barriuso, J., Nagaraju, R. and Hurlstone, A. (2015) Clin. Cancer. Res. 21: 969–975
7. Nguyen, A.T., Emelyanov, A. Koh, C.H.V., et al. (2012) Dis. Mod. Mech. 5, 63-72’
8. White, R.M., Sessa, A., Burke, C., et al. (2008) Cell. Stem. Cell. 2, 183–189
9. Heilmann, S., Ratnakumar, K., Langdon, E.M., et al. (2015) Cancer. Res. 75,
4272–4282
10 . Correia, T., Lockwood, N., Kumar, S., et al. (2015) PLoS. ONE. 10, e0136213
11. Kumar, S., Lockwood, N.L., Ramel, M-C., et al. (2016) Oncotarg. 7,
43939–43948
12. Kak, A.C. and Slaney, M. (1988) Principles of Computerized Tomographic
Imaging. IEEE Press, New York
13. Andrews, N., Ramel, M-C., Kumar, S., et al. (2016) J. Biophot. 9, 414–424
December 2016 © Biochemical Society 15
Shine a Light
Illuminating the
cancer-targeting
potential of
near-infrared
photoimmunotherapy
Hisataka Kobayashi (National Cancer Institute/National Institutes of Health, Bethesda, USA)
Near-infrared photoimmunotherapy (NIR-PIT) is a newly developed cell-selective cancer therapy with
enormous potential for treating cancer in a variety of ways. NIR-PIT not only kills cancer cells, but can also
eliminate other unfavourable cells including cancer stem cells and immunosuppressor cells, among others,
without damaging favourable cells such as immune cells, vascular cells and tissue stem cells. This technique
can efficiently activate anti-tumour host immunity in a way that can even cure untreated distant metastasis.
Motivation to develop NIR-PIT: from
‘see’ to ‘kill’
Figure 1. Scheme explaining the advantages of an activatable imaging probe. Radiolabeled
“always on” anti-HER2 antibody accumulated larger amount in a HER1+/HER2- tumor than
a HER1-/HER2+ tumor that should be the target tumor of anti-HER2 antibody. However,
fluorescence-labeled “activatable” anti-HER2 antibody showed only a HER1-/HER2+ tumor
without showing any other tumors or normal tissue or organs.
16 December 2016 © Biochemical Society
Targeted cancer therapies offer the promise of highly
effective tumour control with fewer side-effects than
conventional cancer treatments. In this approach, drugs
or radioisotopes are directed to a tumour by coupling to
monoclonal antibodies (mAbs) against specific targets on
the cancer cell surface. These antibody–drug conjugates
(ADCs) have had modest commercial success, but sideeffects remain problematic. We have greatly advanced
targeted cancer therapy by developing a series of
optical imaging probes (‘activatable probes’) that only
fluoresce when they are bound to or inside tumours1,2,
enabling precise tracking of cancer cells and drugs in
the tissue3 (Figure 1). With these probes, cancer-specific
fluorescence has been achieved in animal models and in
fresh surgical specimens from cancer patients.
Extending this methodology from ‘see’ for cancer
detection to ‘kill’ for cancer therapy, we then developed
a new form of ADC comprised of an mAb attached to a
photoabsorbing chemical, termed IRDye700DX (IR700).
When this conjugate is injected and the target cancer
tissue is illuminated with harmless near-infrared light
of wavelength 690 nm, the IR700 part of the molecule
Shine a Light
becomes activated and splits, turning hydrophobic,
which compromises the cell membrane, thereby killing
the cancer cell. Our approach is safer than other
conventional ADCs because it only kills illuminated cells
that bind mAb–IR700 conjugates. Since 690 nm light
penetrates skin and tissue to several centimetres in depth
without damaging any normal cells, the therapy can
access most organs from the surface, via endoscopy or
fine needle insertion without surgery. Moreover, the loss
of fluorescence upon activation allows therapeutic effects
to be monitored in real time. We termed this new form
of phototherapy ‘near-infrared photoimmunotherapy’
(NIR-PIT)4 (Figure 2).
NIR-PIT can selectively kill various
cancer cells
The approach works. When NIR-PIT was employed for
targeting cancer cells to be killed in animal models, we
observed significant tumour shrinkage after a single
administration of the conjugate and NIR light, and
repeated exposure to NIR light produced a more than
80% reduction of the exposed tumours with prolonged
disease-free survival and without evident adverse
side-effects. In addition, NIR-PIT has a desirable sideeffect: it initially causes enlargement of the tumour
vasculature, increasing blood flow and permeability.
This ‘super-enhanced permeability, (SUPR)’ effect
begins immediately after therapy and lasts approximately
8 hours, thereby permitting the use of additional
intravenous nano-drug therapies (such as liposomal
chemotherapy), which accumulate up to 24-fold higher
in NIR-PIT-treated tumours5. This treatment is additive
to the direct killing effects of PIT and, in combination,
can result in complete cures of heterogeneous tumours
in animal models (Figure 3).
We have shown that this approach works for
numerous molecular targets and cancer types. By simply
changing the antibody, NIR-PIT can target a broad
array of cancer-specific target molecules including the
proteins EGFR, HER2, PSMA, CD25, CEA, Mesothelin,
GPC3, CD20 and PD-L1, among others. Since NIR-PIT
can achieve spatially selective killing of target cells, it
can be used to eliminate cells containing cancer stem
cell markers such as CD446 and CD1337 as we have
demonstrated for breast cancer and glioblastoma stem
cells, respectively, without harming normal stem cells
expressing these markers in other parts of the body.
Targeting cancer stem cells in this way suppresses
tumour regrowth for long periods (Figure 4).
Targeting systemic metastases
This type of treatment also shows great promise as an
indirect cancer immunotherapy. NIR-PIT achieved
Figure 2. Scheme explaining the basis of near-infrared photoimmunotherapy (NIR-PIT)
Figure 3. Scheme explaining the mechanism of near-infrared photoimmunotherapy (NIR-PIT)
induced super-enhanced permeability and retention (SUPR) effects
spatially selective depletion of tumour-associated
immunosuppressing regulatory T cells (Tregs), which
inhibit anti-tumour attack (and autoimmunity) by
cytotoxic T cells that proliferate within a tumour.
Eliminating Tregs locally in a tumour bed allows
the adjacent cytotoxic T cells to instantly attack the
tumour within 1 hour. Remarkably, Treg-targeting
NIR-PIT also caused the selective systemic regression
of untreated distant metastatic tumours with the
same cell origin as the treated tumour within 2
days, presumably because once awakened, cytotoxic
T cells were no longer susceptible to Treg-induced
December 2016 © Biochemical Society 17
Shine a Light
inactivity8. In contrast, awakened cytotoxic T cells did
not attack normal cells or other cancer cells, ensuring
that Treg-targeting NIR-PIT was a highly cellselective cancer therapy with minimal autoimmune
adverse side-effects of the type seen with systemic
cancer immunotherapies that activate host-immunity
throughout the body (Figure 5).
Future directions
NIR-PIT shows immense promise for practical
and clinical applications. Several NIR-PIT-related
patents were licensed to the start-up biotech company
Aspyrian Therapeutic Inc., which started a phase I
Figure 4. Diagram of the applications of NIR-PIT
clinical trial in June 2015, using the cetuximab–IR700
conjugate (RM-1929) to treat head and neck cancer
patients who had failed to respond to all conventional
cancer therapies (https://clinicaltrials.gov/ct2/show/
NCT02422979). Similar trials are planned for lung,
oesophageal, bladder and pancreatic cancer, some
precancerous conditions including leukoplakia and
papillomatosis, and others in the near future. We
have engaged researchers internationally to further
explore the possibilities of NIR-PIT and to expedite
its introduction into the clinic.
Using recently established genetically similar
tumour models in immunocompetent mice, and
patients enrolled in the ongoing clinical trial, we
have demonstrated that anti-tumour immunity is also
efficiently initiated by intact immune cells, including
dendritic cells and lymphocytes, that are adjacent to
cancer cells undergoing non-apoptotic (i.e. messy and
immunogenic) cell death induced by NIR-PIT9. In
addition, we have found that intact tissue stem cells
in the tumour bed greatly contribute to clean wound
healing, vital for improving the prognosis and quality
of life of cancer patients treated with NIR-PIT.
Because cell membranes across mammalian
species exhibit virtually identical physico-chemical
properties, they are equally susceptible to the
photochemical damage induced by NIR-PIT. Thus,
new NIR-PIT conjugates can be developed in vitro, ex
vivo or in animal models with a very high likelihood
of successful translation to human patients. This
translatability is an important advantage of our
chemistry- and photophysics-based approach to
cancer treatment. NIR-PIT technology opens the
doors for many clinical applications and we hope it
will lead to new treatments for numerous different
cancer types.
■
This research was supported by the Intramural Research
Program of the National Institutes of Health, National
Cancer Institute, Center for Cancer Research.
Figure 5. Scheme explaining the functional mechanism of Treg-targeting near-infrared
photoimmunotherapy (NIR-PIT)
18 December 2016 © Biochemical Society
Dr Hisataka Kobayashi is the Chief
Scientist of the Molecular Imaging
Program, National Cancer Institute/
NIH in Bethesda, Maryland, with over 30
years’ experience in R&D of bio-medical
imaging and drug delivery, especially
targeting cancer for diagnosis and therapy. Dr Kobayashi
holds an MD in Radiology, and a PhD in Immunology/Internal
Medicine from Kyoto University, Kyoto, Japan, and has written
or contributed to more than 270 articles and 50 invited reviews
and book chapters, and has given more than 260 invited lectures
and talks on basic and clinical bio-imaging. Email: Kobayash@
mail.nih.gov
Shine a Light
References
Cancer-associated proteins
1. Kobayashi, H., Ogawa, M., Alford, R., Choyke, P.L., and Urano,
Y. (2010) New strategies for fluorescent probe design in
medical diagnostic imaging. Chem. Rev. 110, 2620–2640
2. Kobayashi, H., and Choyke, P.L. (2011) Target-cancer-cellspecific activatable fluorescence imaging probes: rational
design and in vivo applications. Acc. Chem. Res. 44, 83–90
3. Urano, Y., Asanuma, D., Hama, Y., et al. (2009) Selective
molecular imaging of viable cancer cells with pHactivatable fluorescence probes. Nat. Med. 15, 104–109
4. Mitsunaga, M., Ogawa, M., Kosaka, N., Rosenblum, L.T.,
Choyke, P.L., and Kobayashi, H. (2011) Cancer cellselective in vivo near infrared photoimmunotherapy
targeting specific membrane molecules. Nat. Med. 17,
1685–1691
5. Sano, K., Nakajima, T., Choyke, P.L., and Kobayashi, H.
Abbreviation
Expanded name
Associated cancers
EGFR
Epidermal growth factor
receptor
Squamous-cell carcinoma of the
lung, anal cancers, glioblastoma
and epithelial tumors of the
head and neck
HER2
Human epidermal growth factor
receptor 2
Breast cancer and some gastric
cancer
PSMA
Prostate-specific membrane
antigen
Prostate cancer
CD25
Alpha chain of the interleukin 2
receptor
T-cell neoplasms and some
acute nonlymphocytic
leukemias
CEA
Carcinoembryonic antigen
Colorectal cancer,
adenocarcinomas
6.
GPC3
Glypican-3
Hepatocellular carcinoma
7.
CD20
An activated-glycosylated
phosphoprotein expressed on the
surface of all B-lymphocyte cells
B cell lymphomas and leukemias
Programmed death-ligand 1
Melanoma, lung cancer and
renal cell carcinoma
PD-L1
8.
9.
(2013) Markedly enhanced permeability and retention
effects induced by photo-immunotherapy of tumors.
ACS Nano 7, 717–724
Jin, J., Krishnamachary, B., Mironchik, Y., Kobayashi, H., and
Bhujwalla, Z.M. (2016) Phototheranostics of CD44-positive cell
populations in triple negative breast cancer. Sci. Rep. 6, 27871
Jing, H., Weidensteiner, C., Reichardt, W., et al. (2016)
Imaging and selective elimination of glioblastoma stem
cells with theranostic near-infrared-labeled CD133specific antibodies. Theranostics 6, 862–874
Sato, K., Sato, N., Xu, B., et al. (2016) Spatially selective
depletion of tumor-associated regulatory T cells with nearinfrared photoimmunotherapy. Sci .Transl. Med. 8, 352ra110
Ogawa, M., Tomita, Y., Nakamura, Y., et al. (2016)
Immunogenic cancer cell death selectively induced by
near-infrared photoimmunotherapy (in submission)
December 2016 © Biochemical Society 19
Shine a Light
Light-activated wound healing
and tissue modification
Irene E. Kochevar and
Robert W. Redmond
(Wellman Center
for Photomedicine,
Massachusetts General
Hospital, Harvard Medical
School, USA)
The unique properties of light have led to the development of many effective medical treatments.
Ultraviolet, visible and infrared light can be focused to small tissue volumes, providing spatial specificity
for treatments. The specificity is further enhanced when a dye is applied because the light is only absorbed
in the tissue volume that is stained with the dye. Light can also be delivered in a time-controlled manner
by simply turning on or off a switch. Thus, in contrast to drugs, the treatment can be exquisitely tuned.
Currently, light is frequently used to treat skin diseases such as psoriasis and diseases of the eye such as
keratoconus (involving thinning of the cornea), age-related macular degeneration (AMD) and diabetic
retinopathy, and light is used with dyes to treat certain malignancies. In addition, promising results have
been reported for the destruction of pathogenic microbes by light, with and without a dye. The light
sources employed range from simple fluorescent tubes to high-powered lasers.
When light energy is absorbed by added dyes or native
molecules in tissue, the energy can be converted into
heat (thermal processes), into light at a different
wavelength (called fluorescence), or can initiate
specific chemical reactions (photochemistry). Highenergy pulsed lasers are generally used to induce
thermal processes that can fuse or destroy tissue
for therapeutic benefit. Photochemical reactions
begin with the formation of short-lived (less than a
microsecond) transient species that undergo specific
chemistry with nearby molecules in the tissue such
as certain amino acids, unsaturated lipids, nucleic
acids or oxygen. The products formed may change
the properties of the tissue, e.g. stiffen tissue by
forming crosslinks between proteins, initiate cell
signalling cascades or cause cell death by generating
toxic species, e.g. antibacterial applications as well
as many other beneficial effects. Here, we focus on
light-initiated chemical reactions that trigger wound
healing and tissue modification.
An effective technique for sutureless joining and
sealing of surgical wounds and lacerations has been a
long-sought goal. Chemical and biological glues are used
for specific applications. Energy-based schemes, such
as laser welding of tissues which relies on the thermal
a
b
Sealing wounds with light
Lacerations and surgical incisions are most often
mechanically sealed with sutures or staples although
these methods are not ideal or optimal for all scenarios.
Suture materials, especially non-biodegradable
sutures, can stimulate a strong inflammatory
response leading to worse scarring. This is readily
apparent on skin, where the suture sites can often be
observed as ‘railroad tracks’ along the closed wound.
Also, microsurgical repair with hair-fine sutures for
reconnecting tiny blood vessels, nerves and tendons is
highly time consuming, skill intensive and potentially
damaging since the needles themselves may damage
these small structures.
20 December 2016 © Biochemical Society
Figure 1. Light-initiated crosslinking of proteins for
wound sealing and tissue modification. (a) Steps in the
photochemical tissue bonding procedure. (b) Rose bengal
molecules (pink circles) associate with collagen (wavy lines)
in tissue and are activated by green light. Reactive groups
are formed in proteins that subsequently form covalent
crosslinks (short blue lines) to bridge between tissue surfaces
or to strengthen and passivate tissue.
Shine a Light
effects produced after laser light absorption, have been
evaluated. The peripheral damage accompanying laser
tissue welding has inhibited its application except for
certain uses.
A sutureless method for wound sealing based on
photochemical reactions has been developed. This
photochemical tissue bonding (PTB) technology leads
to the formation of covalent crosslinks between proteins
across a wound without significant temperature increase.
The continuous molecular level bonding between the
two surfaces produces an immediate watertight seal,
which is important for blocking leakage, e.g. from
cornea wounds and inhibiting infection. Essentially, the
linkages reconnect a fraction of the collagen molecules
across the wound (Figure 1). No additional materials
such as glues or added proteins are required, minimizing
any potential inflammatory response. The chemistry
involves the formation of reactive groups on the proteins
that subsequently lead to crosslinks and is enhanced by
the presence of oxygen.
The procedure involves applying a dye that can be
activated by light to the tissue surfaces to be joined,
aligning the surfaces closely to attain secure contact,
then exposing the area to visible light for a few minutes
(Figure 1). The chemical reactions between proteins
occur during light exposure. The dye used, rose bengal,
binds strongly to collagen, which limits its penetration
into tissue and localizes the subsequent photoactivation
with green light to near the tissue surface. In preclinical
studies, PTB successfully sealed and repaired wounds in
skin, cornea, blood vessels, peripheral nerves, tendons
and the bowel.
a
b
Figure 2. Sealing of a surgical wound created to remove a skin lesion. The deep skin tissue
was closed using sutures along the entire wound. The left side of the wound was then
sealed with PTB and the right side closed with standard interrupted sutures. (a) Two weeks
after surgery and immediately after superficial suture removal. Erythema, indicating
inflammation, is much greater on the sutured half of the wound. (b) Six months after
surgery very strong scarring was clearly visible on the sutured half of the wound. (Adapted
from Tsao et al. (2012) Light-activated tissue bonding for excisional wound closure: a splitlesion clinical trial. Br. J. Dermatol. 166, 555–563. Copyright Wiley-VCH Verlag GmbH & Co.
KGaA. Reproduced with permission.)
Photochemical tissue bonding in surgery
In a clinical study, the effectiveness of PTB was
compared with standard interrupted epidermal sutures
for closure of skin excisions1. Following closure of the
deeper layer of skin with absorbable sutures, one-half
of each wound was sealed with non-absorbable sutures
or was treated with PTB (3.3 minutes irradiation time).
After 2 weeks, the PTB-sealed half of the wound showed
less redness (indicating little inflammation) and better
overall appearance than the sutured half of the wound
(Figure 2). After six months of healing, the scar on the
wound half sealed with PTB was rated better in overall
appearance than the scar on the sutured wound half.
In addition, the scar on the PTB half had a narrower
width, possibly related to the lower inflammation and
the continuous seal between the two wound faces
made by the protein crosslinks. Modelling of the light
penetration profile into skin incisions treated with rose
bengal suggested that the crosslinks were formed to at
least 350 µm into the dermis where the light fluence
rate decreased to ~50% of its subsurface peak2.
Figure 3. Schematic showing procedure for photosealing a nerve graft across a peripheral
nerve injury involving nerve deficit. (a) Amnion wrap is partially stained with RB and
applied to one end of the nerve wrap. The overlapping wrap is bonded to the nerve graft
with green light and a second partially stained amnion wrap is applied to the other end
of the graft (b) and then photochemically bonded to the graft (c). RB is then applied to
the inside of the nerve wrap cuffs at both ends and the proximal nerve stump of the host
is inserted into one cuff (d) and illuminated to seal the nerve stump/nerve graft interface.
The distal nerve stump is inserted into the other nerve wrap cuff (e) and illuminated (f) to
seal this nerve stump/nerve graft interface, resulting in a watertight-sealed nerve graft in
continuity with the nerve stumps.
Sealing wounds with a biological membrane
PTB enabled a novel approach for microsurgical wound closure, namely, sealing an amniotic
membrane, a thin, translucent collagenous tissue, over the wound surface to act as a watertight
patch. This approach eliminates or minimizes the number of microsutures, thus saving time
and requiring less skill. One example of this approach is sealing irregularly shaped fullthickness corneal wounds, such as those formed by flying debris entering the eye or by other
trauma. Such complex lacerations can be very difficult to fully seal with sutures. For sealing
December 2016 © Biochemical Society 21
Shine a Light
with PTB, the amniotic membrane is stained with rose
bengal, then placed over the wound and irradiated for a few
minutes. The seal is very tight and resists detachment of the
amnion from the cornea even at pressures 20 times higher
than normal intraocular pressure3.
Sealing an amniotic membrane over a wound with
PTB was also used for the repair of small nerves, as the
formation of a watertight seal over the repair site of
transected nerves prevents leakage of the neurotrophic
and neurotropic factors that are essential for axonal
regrowth, prevents axonal escape from the endoneural
architecture, and reduces inflammation and scarring
caused by suture trauma. When an amniotic membrane
stained with rose bengal was sealed with PTB over the
nerve repair site, nerve regeneration improved relative to
standard care, namely, microsurgery using fine sutures.
This approach was also highly effective when used to seal
nerve grafts in place where there had been nerve damage
caused by trauma (Figure 3)4.
In the course of these studies a reduction in
scarring, fibrosis and post-surgical adhesions was
observed in and around the healing nerve tissue.
This observation gave rise to the idea that PTB
sealing of an amniotic membrane and other thin
biocompatible materials over wound surfaces could
inhibit the formation of post-surgical adhesions,
a serious complication of surgeries such as bowel
Figure 4. Rose bengal remains close to the surface of tissues.
Rose bengal was applied to the front surface of an ex vivo cornea,
after removal of the epithelial layer. The dye diffuses into, and
remains only, in a narrow band near the surface as shown by the
red colour indicating RB fluorescence. The cell nuclei are shown
in yellow in this frozen section of cornea tissue. (Adapted from
Cherfan et al. (2013) Collagen crosslinking using rose bengal and
green light to increase corneal stiffness. Invest. Ophthalmol. Vis.
Sci. 54, 3426–3433.Copyright Association for Research in Vision
and Ophthalmology. Reproduced with permission.)
22 December 2016 © Biochemical Society
wound closure and repair of ruptured Achilles
tendon that can cause internal organs and tissues to
stick together in abnormal ways. Preclinical studies
validated this concept for bowel repair5.
Altering the mechanical and biological
properties of tissue
The photochemical reactions initiated in tissues by dyes
such as rose bengal have many other applications in
addition to sealing wounds. Crosslinking extracellular
matrix proteins results in a mechanically stronger and
stiffer tissue that can better resist mechanical forces. One
example is photochemical crosslinking of collagen in the
cornea to treat keratoconus. In this disease, the corneal
collagen fibres weaken over time leading to a protrusion
of the corneal surface, due to reduced resistance against
normal intraocular pressure. Collagen crosslinking
using riboflavin-5-phosphate (riboflavin) and ultraviolet
A (UVA) light is used clinically6. Riboflavin (also known
as vitamin B2) is applied to the cornea surface and
penetrates into the collagen-rich stroma. Exposure of the
surface to UVA for up to 30 minutes increases the cornea
stiffness sufficiently to inhibit further progression of
cornea protrusion and loss of visual acuity.
a
b
Figure 5. Bilateral interpositional saphenous vein grafts in
carotid arteries of swine. (a) PTP-treated and (b) untreated
control vein grafts one month post-surgery. Control graft is
extensively dilated and tortuous in appearance while PTPtreated does not undergo these drastic changes.
Shine a Light
The alternative use of rose bengal and green light
overcomes some of the limitations of the riboflavin/UVA
approach, such as being limited to treating corneas that are
more than 400 µm thick. Thinner corneas do not retain
sufficient riboflavin to protect the very critical endothelial
cell layer from photodamage. In contrast, rose bengal diffuses
only a short distance into the cornea (~100 µm) (Figure 4) and
other tissues where it absorbs the incident green light. The
photochemical crosslinking occurs only in this rose bengalstained volume producing the same stiffness observed with
riboflavin/UVA, without risk to the endothelium7,8.
Exposing the surface of veins to rose bengal and
green light has also been shown to improve the outcomes
of venous grafts when placed in higher-pressure arterial
systems. After placing a normal graft in arterial flow, the
vein initially distends leading to endothelial damage,
vascular smooth muscle cell migration and ultimately
stenosis (narrowing) resulting from intimal hyperplasia
in the vessel lumen. To prevent the distension of the
vein, rose bengal was applied to the external (adventitial)
surface of the vein graft which was then illuminated for a
few minutes with green light to crosslink the adventitia9.
Both short- and long-term outcomes were striking with
reduced intimal hyperplasia and higher blood flow
through the graft (Figure 5). Similar problems of intimal
hyperplasia and graft failure occur in arteriovenous
fistulas (abnormal or surgically created connections
between veins and arteries) that are created to provide an
easier access point for haemodialysis treatment (process
of blood purification) for end-stage renal disease
patients. In preclinical studies, improved outcomes
were again observed from photocrosslinking treatment
immediately prior to arteriovenous fistula formation.
As changes in the biological properties of the tissues, in
addition to tissue stiffening, may be responsible for the
decreased intimal hyperplasia, this treatment is called
photochemical tissue passivation (PTP).
The dense network of collagen crosslinks produced
within a tissue by PTP may act as a barrier to cell
migration. This effect appears to be operating when
PTP is used to prevent wound contracture. In a rabbit
model of breast implant insertion, PTP was applied
to the tissue pocket created beneath the skin prior to
receiving the model breast augmentation implant10.
This treatment inhibited the inflammatory response
and capsule formation around the implant that are
typical complications arising in women receiving breast
augmentation surgery. A significantly smaller fibrous
capsule developed and there was no smooth muscle
actin in the capsule of the PTP-treated tissue compared
with the control, suggesting that PTP decreased the
activity of myofibroblast cells by possibly preventing
fibroblast cell migration through the crosslinked
tissue. Initial studies in mice have also demonstrated
the ability of PTP to inhibit wound contracture in full-
thickness skin wounds, again suggesting that fibroblast migration and myofibroblast
activity is modulated by crosslinking the skin dermis.
What’s next?
Applications of protein photocrosslinking in medicine seem almost limitless. Possibilities
include linking biomaterials to tissues, nano-bonding cells to cells, producing barriers
to cell migration in connective tissues and creating crosslinks deep in tissue using novel
light delivery devices. On a practical, near-term level, the next step involves clinical trials
for the many applications that have been demonstrated in animal studies.
■
Irene Kochevar is Professor of Dermatology at Harvard Medical School with
laboratories in the Wellman Center for Photomedicine of Massachusetts
General Hospital. She has applied her background in physical organic
chemistry and biochemistry to generate an understanding of fundamental
mechanisms by which UV radiation and dye photosensitization generate
oxidative stress in cells and the responses of cells to this stress. Professor
Kochevar is a co-inventor of a light-activated tissue repair technology based
on protein photocrosslinking that, in studies with medical collaborators, has been shown to have
multiple applications including sealing wounded skin, cornea, nerves, tendons as well as stiffening
corneas. Email: [email protected]
Robert W. Redmond is an Associate Professor in the Department of
Dermatology at Harvard Medical School. His research at the Wellman Center
for Photomedicine, in collaboration with the Department of Surgery at
Massachusetts General Hospital, utilizes photochemical reaction mechanisms
to develop new technologies for wound closure, tissue regeneration,
biomechanical modification of tissue and modulation of inflammatory
response during wound healing. Email: [email protected]
References
1. Tsao, S., Yao, M., Tsao, H., et al. (2012) Light-activated tissue bonding for excisional wound
closure: a split-lesion clinical trial. Br. J. Dermatol. 166, 555–563
2. Yao, M., Yaroslavsky, A., Henry, F.P., Redmond, R.W. and Kochevar, I.E. (2010) Phototoxicity is
not associated with photochemical tissue bonding of skin. Lasers Surg. Med. 242, 123–131
3. Verter, E.E., Gisel, T.E. Yang, P., et al. (2011) Light-initiated bonding of amniotic membrane to
cornea. Invest. Ophthalmol. Vis. Sci. 52, 9470–9477
4. Fairbairn, N.G., Ng-Glazier, J., Meppelink, A.M., et al. (2016) Improving outcomes in
immediate and delayed nerve grafting of peripheral nerve gaps using light-activated
sealing of neurorrhaphy sites with human amnion wraps. Plast. Reconstr. Surg. 137,
887–895
5. Ni, T., Senthil-Kumar, P., Dubbin, K., et al. (2012) A photoactivated nanofiber graft material
for augmented Achilles tendon repair. Lasers Surg. Med. 44, 645–652
6. Randleman, J.B., Khandelwal, S.S. and Hafezi, F. (2015) Corneal cross-linking. Surv.
Ophthalmol. 60, 509–523
7. Cherfan, D., Verter, E.E., Melki, S., et al. (2013) Collagen cross-linking using rose bengal and
green light to increase corneal stiffness. Invest. Ophthalmol. Vis. Sci. 54, 3426–3433
8. Zhu, H., Alt, C., Webb, R.H., Melki, S. and Kochevar, I.E. (2016) Corneal crosslinking with rose
bengal and green light: efficacy and safety evaluation. Cornea 35, 1234–1241
9. Goldstone, R.N., McCormack, M.C., Khan, S.I., et al. (2016) Photochemical tissue passivation
reduces vein graft intimal hyperplasia in a swine model of arteriovenous bypass grafting. J.
Am. Heart. Assoc. 5, doi.org/10.1161/JAHA.116.003856
10. Fernandes, J.R., Salinas, H.M., Broelsch, G.F., et al. (2014) Prevention of capsular contracture
with photochemical tissue passivation. Plast. Reconstr. Surg. 133, 571–577
December 2016 © Biochemical Society 23
Shine a Light
Photobiomodulation
and the brain – has
the light dawned?
Michael R. Hamblin (Wellman Center for Photomedicine, Massachusetts General Hospital, USA)
Evidence is mounting that photobiomodulation therapy (shining near-infrared light) can
benefit a wide range of brain disorders. The photons can penetrate into the brain where they
stimulate production of energy in brain cells, and trigger numerous signaling pathways. Acute
ischaemic stroke was the first indication that progressed to human clinical trials. Acute and
chronic stages of traumatic brain injury were then investigated. Currently, psychiatric disorders
such as depression, and neurodegenerative diseases such as Alzheimer’s and Parkinson’s are
under investigation. Although showing great promise, more trials are clearly needed before
the therapy will be accepted.
Photobiomodulation therapy
Photobiomodulation therapy (PBMT) is defined as
the use of low (non-thermal) levels of visible or nearinfrared (NIR) light to stimulate or inhibit biological
cells and tissues via a photochemical mechanism
(without the addition of an external photosensitizer).
PBMT was discovered almost 50 years ago (1967) by
Endre Mester in Hungary. He was trying to cure a
tumour implanted in a rat using a beam produced
by the newly discovered ruby laser. As it happens,
the power of the laser beam was much lower than
he expected and he was unsuccessful in curing the
Figure 1. Mechanism of absorption of light by chromophores in cells. ATP = adenosine
triphosphate; ROS = reactive oxygen species; TRPV = transient receptor potential vanilloid
24 December 2016 © Biochemical Society
tumour. However, he was surprised to observe in
treated animals that the incisions made to implant
the tumour healed faster than the controls, and the
shaved hair also grew back faster. Mester called
this phenomenon ‘laser biostimulation’ and it later
became known as ‘low-level laser therapy’, or LLLT 1.
The mechanism of action of PBMT has been under
intense investigation ever since it was discovered,
but in recent years there has been some consensus
among experts on this thorny topic2. The principal
chromophore (light-absorbing molecule) has been
identified as cytochrome c oxidase (CCO), which is
unit IV of the mitochondrial respiratory chain and
responsible for reducing oxygen to water with the
simultaneous production of protons that are used to
drive the synthesis of adenosine triphosphate (ATP),
i.e. the cellular energy source. The fact that CCO
absorbs light in the red region of the visible spectrum
(600–690 nm) and in the NIR (760–940 nm),
which are the most clinically effective wavelengths,
bolsters this hypothesis. One of the most general
observations made in PBMT is an increase in ATP in
cells and tissues. Recently, it has become likely that
there is a second chromophore that absorbs longer
wavelengths (980 nm and 1064 nm), and this has
been tentatively identified as water (possibly in the
form of nanostructured water which is a thin layer
that forms on biological membranes). This may be
particularly important in activating transient receptor
potential (TRP) ion channels. The mechanism of PBM
absorption by chromophores is shown in Figure 1.
Shine a Light
A single brief exposure of animals or humans
to light during PBMT can have surprisingly longlasting effects (days or weeks). It has been shown that
signalling pathways are triggered within the cells,
transcription factors are activated and gene expression
patterns are altered. Exposure to PBMT results in key
physiological changes – increased anti-inflammatory
cytokine levels, decreased pro-inflammatory cytokine
levels, upregulation of anti-oxidants and survival
factors, increased cell proliferation and reduced levels
of apoptosis. At the tissue level, blood flow is increased,
lymphatic drainage is also increased leading to reduced
oedema (fluid build-up), healing is improved as
shown by improved angiogenesis, cell migration and
collagen synthesis (Figure 2). One recent and exciting
development has been the observation that stem cells
respond very well to PBMT. It has even been possible to
shine light on the leg bones of mice to activate stem cells
in the bone marrow that can then migrate throughout
the body via the bloodstream and can repair defects in
the heart, kidney or brain 3.
There have been a wide variety of clinical applications
of PBMT that have been tested to date, including wound
healing indications for non-healing leg ulcers, diabetic
foot ulcers and pressure sores, and reducing the pain
and inflammation of the musculoskeletal system, in such
disorders as tendinopathies, osteoarthritis, sprains, neck
pain, carpal tunnel syndrome and tennis elbow. Many
applications of PBMT have been in the field of dentistry,
such as post-extraction pain, orthodontics, periodontitis,
oral mucositis and temporomandibular joint disorder.
Some purely aesthetic applications include the reduction
of facial wrinkles, hair regrowth to treat baldness and fat
layer reduction. A graphical illustration of the diverse
medical applications of PBMT is shown in Figure 3.
Figure 2. Cellular and tissue mechanisms of PBM. SOD = superoxide dismutase.
Lighting the brain
Workers in tissue optics have estimated that between
2–5% of light incident on the head, depending on the
wavelength and exact location on the skull, penetrates
to the surface of the brain4. However, there is some
evidence that there may also be a systemic effect of
PBMT mediated via the bloodstream, and that the
bone marrow in the skull may also be stimulated.
While much of the work until now has used lasers,
the recent advent of NIR light emitting diode (LED)
arrays with reasonable power outputs has provided a
cost-effective and safer alternative.
Focus on stroke
Uri Oron in Israel and the Photothera company in the
US were the first to test PBMT for brain disorders in
an animal model of acute ischaemic stroke5. Rats had a
Figure 3. Diversity of medical applications of PBMT. TBI = traumatic brain injury.
filament introduced into the middle cerebral artery to
create a permanent blockage, and were treated with a
single exposure to an 808 nm laser spot on the shaved
head 24 hours post-stroke. Improvements were seen
in neurological function that lasted for 4 weeks. They
went on to show that motor functioning and clinical
behaviour ratings were improved in a rabbit small
clot embolic stroke model that had been irradiated
6–24 hours post-stroke. These promising results led
to three human clinical trials NEST-1, NEST-2 and
NEST-3. Although the first two trials showed positive
results, the last trial (planned for 1000 patients) was
December 2016 © Biochemical Society 25
Shine a Light
prematurely halted for futility at an intermediate
stage. Many reasons have been put forward to explain
this failure, including an insufficient dose of light,
the fact that only a single application was given, and
the possibility that the areas of the head that were
illuminated were sub-optimal 6.
Treating traumatic brain injury
Oron was again the first to test PBMT in an animal
model of traumatic brain injury (TBI). In a mouse
model of closed head injury, he showed that a single
application of an 808 nm laser to the head within 6
hours of a TBI, produced long-lasting improvements
in neurological function7. The Hamblin laboratory in
the US8 went on to show, in a mouse model of closed
Figure 4. Transcranial PBMT for major depression. (a) Application of NIR LED to the forehead
(b) Improvement in Hamilton depression score after 2 weeks.
head injury, that 660 nm and 810 nm lasers (but not
730 nm or 980 nm), delivered 4 hours post-TBI,
produced significant improvements in neurological
function. The same group went on to show in mice
with TBI that exposure to an 810 nm laser increased
neuroprogenitor cells and brain-derived neurotrophic
factor (BDNF) in the dentate gyrus (part of the
hippocampus) and in the subventricular zone at 7
days post-TBI. Interestingly, there was upregulation
of synapsin-1 (a marker of formation of newly formed
synapses) in the cortex at 28 days post-TBI. This
process of synaptogenesis or neuroplasticity describes
how the undamaged part of the brain can remodel
itself to take over the functions of the damaged
parts. Taken together, these observations show
that PBMT can help the brain to repair itself after
suffering damage. Other workers have also shown
that PBMT can reduce activated microglia in mouse
brains after TBI, showing that neuroinflammation
can also be reduced. Increased neuroinflammation,
reduced neurogenesis, lowered BDNF and impaired
synaptogenesis are characteristic observations in a
wide variety of brain disorders, including psychiatric
disorders and neurodegenerative diseases.
Initial clinical studies of PBM for chronic TBI in
humans have been carried out by Margaret Naeser and
co-workers9. They showed that after receiving a total
of 18 LED (red and NIR) treatments, subjects saw
improvements in executive functioning and verbal
memory, as noted by improved scores on the Stroop
test and California Verbal Learning Test. Patients
with chronic TBI have abnormalities in the default
mode network, the central executive network and
the salience network areas of the brain (see glossary).
Typically, they have impaired ability to deactivate the
default mode network, meaning that rapid switching
between networks cannot occur, hindering overall
cognitive performance. The Naeser lab has carried out
pilot research demonstrating that functional magnetic
resonance imaging scans of the brains of patients with
chronic aphasia, both before and after a series of 18
LED treatments, indicated increased connectivity
between neural nodes in all three networks affected by
TBI. In a further series of patients with chronic TBI,
they found that eight out of 11 subjects had marked
improvement in cognitive function.
PBMT for depression and anxiety
Figure 5. Diversity of brain conditions and diseases that may be amenable to treatment with PBMT
26 December 2016 © Biochemical Society
Animal experiments have shown that mice and rats
subjected to PBMT demonstrate improvement in
behavioural tests designed to measure depression
and anxiety (for instance forced swim test and tail
suspension test). Schiffer et al. conducted a pilot clinical
study in 10 patients with major depression and anxiety,
Shine a Light
in which they received a single 810 nm LED treatment
to the forehead at two locations for 4 minutes each
10 (Figure 4). It was found that, after two weeks, the
mean Hamilton Depression Rating Scale (HDRS) had
decreased by about 10 points (23.9 to 13.2) although by
the four-week mark symptoms had begun to reappear.
Cassano and colleagues studied the effects of multiple
PBMT treatments (810 nm laser) administered over
three weeks. At completion of the study, two out of four
patients had achieved remission, and the mean HDRS
score had decreased from the baseline of 19.8 to 13.0.
PBMT for Parkinson’s disease
John Mitrofanis and co-workers in Australia have
studied PBMT for Parkinson’s disease in animal
models11. They found that dopaminergic cells in
the substantia nigra pars compacta (SNc) were
protected from toxicity caused by MPTP (a drug
used to induce Parkinson’s symptoms). They went
on to test a surgically implanted intracranial fibre
designed to deliver either 670 nm LED (low power)
or 670 nm laser (high power) into the lateral
ventricle of the brain in MPTP-treated mice. Both
low-power LED and high-power laser were effective
in preserving SNc cells, but the laser was considered
to be unsuitable for long-term use (6 days) due
to excessive heat production. These authors also
reported a protective effect of light exposure when
the head was shielded in this mouse model. Recently,
this group has tested their implanted fibre approach
in a model of Parkinson’s disease in adult Macaque
monkeys treated with MPTP. Clinical evaluation
of Parkinson’s symptoms (posture, general activity,
slowness of movement and facial expression) in
the monkeys were improved at low doses of light
compared with high doses.
PBMT for Alzheimer’s disease
De Taboada and colleagues tested the effects of PBM
in a transgenic mouse model of Alzheimer’s disease
(amyloid-β protein precursor, AβPP)12. Beginning at
three months of age, PBMT was administered three
times a week. Aβ plaque numbers were decreased
and amyloid levels within the brain were reduced.
Importantly, PBMT also mitigated the behavioural
effects seen with advanced amyloid deposition and
reduced the expression of inflammatory markers
in the AβPP transgenic mice. Other workers have
seen similar results in different mouse models of
Alzheimer’s. A few small trials have already been
conducted of PBMT for Alzheimer’s in humans and
the results seem promising.
PBMT for enhanced cognitive performance
While many studies have noted the positive effects
of PBM on cognition and memory, very few have
studied it for the sole purpose of improving the
cognitive functioning of healthy subjects. A doubleblind, placebo-controlled study conducted by Barrett
and Gonzalez-Lima, tested the effect of PBM on the
memory and attention of a class of 40 undergraduate
students13. Subjects received treatment with 1064 nm
light at two different sites on the right frontal pole of
the cerebral cortex. After two weeks, it was found that
subjects who received real treatment saw noticeable
cognitive improvements (faster reaction times and
better performance on a memory test).
What does the future look like?
The wide variety of brain conditions and diseases
that may be amenable to treatment using PBMT
are illustrated in Figure 5. There are at present no
pharmaceutical drugs to treat brain damage caused by
either stroke or TBI. Moreover, despite huge amounts
of funding and research in both academic labs and
industry, progress in discovering drugs to halt the
progression of both Alzheimer’s and Parkinson’s
disease has been frustratingly slow. Perhaps it is time
to undertake serious well-designed clinical trials of
transcranial PBMT for these indications, considering
its established safety record and notable lack of
adverse effects, not forgetting its relatively costeffective nature. Although psychiatric drugs, such
as anti-depressants and anxiolytics (anti-anxiety),
are well-established and rank among some of the
world’s biggest selling pharmaceuticals, their rate of
effectiveness is considered to be disappointing, and
they can have high rates of distressing side-effects.
Now that cost-effective and safe LED arrays in the
NIR spectrum are becoming available, home-based
treatments for these chronic diseases have become
entirely feasible.
■
Michael R Hamblin Ph.D. is a Principal
Investigator at the Wellman Center for
Photomedicine, Massachusetts General
Hospital and an Associate Professor of
Dermatology at Harvard Medical School.
His research interests are in photodynamic
therapy and photobiomodulation. He has published 345 peerreviewed articles, and 24 textbooks. He has an h-index of 75 and
over 20000 citations. He is Associate Editor for 9 journals, serves
on NIH Study-Sections and in 2011 was honored by election as a
Fellow of SPIE. Email: [email protected]
December 2016 © Biochemical Society 27
Shine a Light
Glossary
Amyloid-β protein precursor
Leads to plaque formation in the brain of Alzheimer’s patients
Adenosine triphosphate
The chief energy source for all cells and tissues
Aphasia
Problems understanding and forming words due to malfunction in specific brain regions
Brain-derived neurotrophic factor
The most important single factor for optimal brain function and repair
Cytochrome c oxidase
An enzyme inside mitochondria responsible for metabolizing glucose and oxygen to form ATP
Central executive network
An area in the brain responsible for decision-making
Default mode network
An area in the brain active during day-dreaming
Hamilton Depression Rating Scale
A questionnaire measuring symptoms of depression
Neurothera effectiveness and safety trial
A series of three clinical trials designed to test whether photobiomodulation therapy using an near-infrared laser
was effective in acute stroke
Salience network
An area in the brain responsible for discriminating between sensory inputs
Substantia nigra pars compacta
An area of the brain that produces the neurotransmitter dopamine, and is damaged in Parkinson’s disease
Transient receptor potential
A family of ion channels activated by diverse stimuli including heat and light
References
1. Chung, H. et al. The nuts and bolts of low-level laser (light) therapy. Ann
Biomed Eng 40, 516-533, doi:10.1007/s10439-011-0454-7 (2012).
2. De Freitas, L. F. & Hamblin, M. R. Proposed Mechanisms of
Photobiomodulation or Low-Level Light Therapy. IEEE Journal of
Selected Topics in Quantum Electronics 22, 7000417 (2016).
3. Oron, A. & Oron, U. Low-Level Laser Therapy to the Bone Marrow
Ameliorates Neurodegenerative Disease Progression in a Mouse Model
of Alzheimer’s Disease: A Minireview. Photomed Laser Surg, doi:10.1089/
pho.2015.4072 (2016).
4. Tedford, C. E., DeLapp, S., Jacques, S. & Anders, J. Quantitative analysis of
transcranial and intraparenchymal light penetration in human cadaver
brain tissue. Lasers in surgery and medicine 47, 312-322, doi:10.1002/
lsm.22343 (2015).
5. Oron, A. et al. Low-level laser therapy applied transcranially to rats after
induction of stroke significantly reduces long-term neurological deficits.
Stroke 37, 2620-2624, doi:10.1161/01.STR.0000242775.14642.b8 (2006).
6. Lapchak, P. A. & Boitano, P. D. Transcranial Near-Infrared Laser Therapy
for Stroke: How to Recover from Futility in the NEST-3 Clinical Trial. Acta
Neurochir Suppl 121, 7-12, doi:10.1007/978-3-319-18497-5_2 (2016).
7. Oron, A. et al. low-level laser therapy applied transcranially to mice following
traumatic brain injury significantly reduces long-term neurological deficits. J
Neurotrauma 24, 651-656, doi:10.1089/neu.2006.0198 (2007).
28 December 2016 © Biochemical Society
8. Thunshelle, C. & Hamblin, M. R. Transcranial low-level laser (light) therapy
for brain injury Photomed Laser Surg in press (2016).
9. Naeser, M. A. & Hamblin, M. R. Traumatic Brain Injury: A Major Medical
Problem That Could Be Treated Using Transcranial, Red/Near-Infrared
LED Photobiomodulation. Photomed Laser Surg, doi:10.1089/
pho.2015.3986 (2015).
10. Schiffer, F. et al. Psychological benefits 2 and 4 weeks after a single
treatment with near infrared light to the forehead: a pilot study of 10
patients with major depression and anxiety. Behav Brain Funct 5, 46
(2009).
11. Johnstone, D. M., Moro, C., Stone, J., Benabid, A. L. & Mitrofanis, J. Turning
On Lights to Stop Neurodegeneration: The Potential of Near Infrared
Light Therapy in Alzheimer’s and Parkinson’s Disease. Front Neurosci 9,
500, doi:10.3389/fnins.2015.00500 (2015).
12. De Taboada, L. et al. Transcranial laser therapy attenuates amyloid-beta
peptide neuropathology in amyloid-beta protein precursor transgenic
mice. J Alzheimers Dis 23, 521-535, doi:10.3233/JAD-2010-100894
(2011).
13. Barrett, D. W. & Gonzalez-Lima, F. Transcranial infrared laser
stimulation produces beneficial cognitive and emotional
effects in humans. Neuroscience 230, 13-23, doi:10.1016/j.
neuroscience.2012.11.016 (2013).
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Interview
Let it glow
In the run up to the holidays we all start to think about preparations - food, presents, decorations,
digging out that box of fairy lights from the attic to decorate the Christmas tree. But what if we could
buy a real, self-illuminating (autoluminescent) tree that didn’t require lights? This may seem like the
stuff of films and TV, but could it actually become a reality in the not too distant future? Helen Albert
addresses this and other questions about bioluminescence with US-based biochemist and entrepreneur
Alexander Krichevsky, who created the first autoluminescent plant in 2010, as well as Russian chemist
Ilia Yampolsky, who helped discover the chemical mechanism of bioluminescence in fungi last year.
Following some improvements to the prototype, Krichevsky’s company Gleaux (formerly Bioglow
Tech) now produces and markets glowing ornamental tobacco plant plants. These plants have been
genetically engineered to emit light by inserting genes from bioluminescent bacteria. While the glow
is still not bright enough to replace conventional lighting, Krichevsky and team have managed to
increase the brightness of the glow more than 10-fold since 2010.
Bacteria are by no means the only species that give off light in nature. Bioluminescence has evolved
a number of times in different species, for example, in some species of fish, jellyfish and in insects such
as fireflies, as well as in bioluminescent mushrooms. Like something out of Alice in Wonderland, there
are more than 75 different species of these fungi to be found illuminating woods and jungles around
the world. Until recently, little was known about the chemical basis of this process, but Ilia Yampolsky
and colleagues in Russia have now discovered how the mechanism of fungal bioluminescence works.
Their work demonstrated that the chemical that causes the glow, known as luciferin, is different to
that found in other bioluminescent species. They also believe that fungal luciferin has the potential to
help produce autoluminescent plants, as the system is compatible with plant biochemistry.
Home lighting eco-style
Alexander Krichevsky began his career by doing a
PhD on viral inhibitors, working on HIV, at the Hebrew
University in Israel. Following this, he went to the
State University of New York and started working on
transgenic plants. After a few years he decided that a
life in academia was not for him and decided to start a
biotech company called Bioglow (now Gleaux).
Starlight Avatar plant in light (left) and darkness (right)
30 December 2016 © Biochemical Society
How did your company come into being?
I started my first company when I was still in Stony Brook,
which was about 2007. When I decided to produce glowing
plants I needed to find people who would be interested in
helping me to fund it so I was basically talking to different
people about this for about 3-4 months. I was kicked out of
every place, I was laughed at, people were telling me that it
was never possible that plants cannot emit light that they
just don’t have enough energy and other things. Nobody
believed me. Basically, I was a local laughing stock. But
eventually I met a few people who said maybe there is
something to it. One of the first people who believed in
me was my business partner Tal Eidelberg; he owns a
software company in New York. He helped me start it up
and we are still good friends and business partners and
that’s how it all started. We started with essentially nothing
and we developed the prototype autoluminescent plant
by 2010. Once we had the prototype the company got
significantly more funding and I was able to quit my job
at the university.
What made you decide to focus on glowing plants?
I just felt that academia wasn’t my thing. I like to do
things that are useful to people, don’t just only have a
philosophical value. I wanted to do something that
people can actually use. Before I wanted to start my
company, I thought ‘what kind of company am I going
Interview
Biobulb, a symbol of future use of plants instead of electricity
to start?’. I had a list of ideas that I always wanted to try
and I wanted to pick the one that was the least crazy.
Strangely, glowing plants was probably the least crazy
one on the list so that’s why I picked it!
matter how good the science is you still need to secure funds to do that. And the third
thing is obviously the technical challenges that you have to overcome, but those are
probably the least problematic. If you are a professional and you know what you are
doing that’s the least troubling aspect of the whole thing.
How did you go about creating that first glowing
plant and how does it differ from what you’ve
moved onto now?
We took the genes straight out of bioluminescent marine
bacteria and put them in the plants. The system is
called the lux operon. It contains six genes, two of them
encode luciferase, the enzyme that makes light, and the
other four make substrates for the reaction. So what
you’ve got to do is take the lux operon and put it in the
chloroplast genome and then you get yourself a glowing
plant. Marine bacteria and plants are evolutionarily very
different and there are a lot of years between them in
evolutionary distance, so it’s very hard for plants to read
the code from marine bacteria. It’s like if I gave you a
piece of Mayan language to read with no translation, we
wouldn’t be able to do that. Fortunately, the plants were
able to do it. It was very inefficient, there was very little
light, but they were still able to do it and that’s how we
showed that the prototype was working.
Since 2010, we’ve adapted the existing genes to be better
read and understood by the plants, which lets us do the
whole process more efficiently. In the plants we have right
now, we have already enhanced the glow maybe somewhere
between 10-100 fold, so now it’s much brighter.
Why did you choose bacterial genes as a source of luminescence?
There are, I believe, about 30 different bioluminescence systems with diverse evolutionary
origins that are completely different biochemically and genetically. Some of them produce
substrates that it would not be possible to produce in plants. They may produce some side
compounds which that particular organism can take care of, but plants probably won’t
be able to. In bacterial systems the only by-product is water. So for this and a number of
other reasons we decided to go with the bacterial system. When we started there was so
many ways for it to fail, we were by no means sure it was going to work, but we felt it was
the best fit out of the many options.
What are the key challenges you have you faced
along the way?
If would pick three top ones, number one - convincing
people to believe its real, that’s the most important
challenge. The second challenge is funding, you know
nothing moves forward without funding, it doesn’t
What are you working on now?
I’ve now moved onto another idea from my list. For about 50 years people have been
trying to get plants to fix nitrogen straight from the air, as if that would happen then
you wouldn’t have to fertilise them, at least not as we do now. That would allow farmers
to save a lot of money. It takes a lot of energy to create nitrogen fertiliser and it would
save a lot on greenhouse gases. I think we have created the first prototype of plant that
is actually able to fix nitrogen from the air. So that’s another crazy one!
I’m running into the same problems as I did with the glowing plants. Nobody
believes me at this point. This is a controversial area and people say “Well, it can’t work”,
but I have results that show otherwise and somebody else who I can’t name, as it’s a
company I have a non-disclosure agreement with, agreed and said yes we see the same
stuff. So I have an interesting result, but there is still a long way to go.
Will we be able to put our Christmas lights in the bin and buy a self lighting
Christmas tree in the future?
Of course! It’s all a matter of funding. Now the system is working all you have to
do is fund it and you will get a glowing Christmas tree. The basic glow mechanism
should work in any plant. There is no reason why it wouldn’t. The barrier is the actual
transformation to put the genes inside. There is no doubt technically it can be done, its
just when are people going to have enough will to put the lights in the garbage bin and
get the glowing tree.
■
December 2016 © Biochemical Society 31
Interview
How does your mushroom glow
Ilia Yampolsky has worked at the Institute of
Bioorganic Chemistry of the Russian Academy of
Sciences with Sergey Lukyanov since 2002, where he
received his PhD in biochemistry in 2009 for structure
elucidation of the chromophores of red fluorescent
proteins. Now he is the head of the research group at
the same Institute. His main research interests include
studying new bioluminescent systems, fluorescent
and fluorogenic dyes, evaluation of biosynthetic
mechanisms, medicinal chemistry and total synthesis
of natural products.
What made you decide to research the
mechanism behind glowing mushrooms and
how did you go about this?
The first systematic studies of bioluminescence
were conducted by Newton Harvey in the early 20th
century. He coined the terms luciferin and luciferase,
and realized that bioluminescence is always associated
with oxidation by oxygen. Later Harvey’s ideas were
further developed by one of his students – Woodland
(Woody) Hastings, and in turn by Hastings’
own students, among whom was the Nobel prize
winner Osamu Shimomura. Consequently, a single
community emerged being engaged in research of
biochemical reactions involving oxygen, chemo- and
bioluminescence, fluorescence and the underlying
biophysical processes: mechanisms of formation
and relaxation of the excited states of chromophores
and fluorophores. For a while all of these studies
progressed side by side.
In Russia, these ideas were propagated by the
efforts of Yulii Labas and Joseph Gitelson. Dr Labas
32 December 2016 © Biochemical Society
initiated the search for fluorescent proteins in corals,
which resulted in the discovery of red fluorescent
proteins by Sergey Lukyanov and his group. Dr Labas
also encouraged me to begin the search for fungal
luciferin. At the same time Professor Gitelson’s
research fellow, Konstantin Purtov, was engaged
in the purification of fungal luciferin experiments.
In 2011, an international research project led by
Shimomura and supported by a ‘mega grant’ from
the Russian government began in Krasnoyarsk,
bringing together the laboratories of Lukyanov and
Gitelson. This collaboration resulted at first in the
identification of fungal luciferin and eventually
fungal luciferase (our article on fungal luciferase is
in preparation).
What challenges have you faced along the way?
Surprisingly the amount of luciferin in
bioluminescent mushrooms is very low, and this
molecule is very unstable, unlike its precursor. As to
the luciferase, we have found that it is a membrane
protein and it inevitably loses activity in solution.
All of these factors are crucial for purification and
determination of activity of components of any novel
bioluminescent system.
How many types of glowing mushroom are there
and do they all have the same mechanism (to
your knowledge)?
As of current date a total of 102 species of
bioluminescent mushrooms were discovered,
many of which were systematized and reported by
Cassius Stevani (Brazil). In 2010, Stevani together
with А. Oliveira demonstrated that the mechanism
underlying fungal bioluminescence is universal
Interview
I know autonomous bioluminescent plants will be on
the market in the next few years. Whether they might
become a sufficient or cost-effective light source is
a question that we prefer to answer experimentally,
however, we believe that even if the glowing plants
are not the new LEDs, they will become a symbol of
the coming biotech era and will change the common
perception of the genetically modified organisms.
Apart from bacteria, biosynthetic pathways
of luciferins are not known for other investigated
bioluminescent systems. We are currently very close
to establishing the full biosynthetic chain for fungal
bioluminescent system, which eventually will make
it the first fully encoded system in eukaryotes.
Ilia Yampolsky and colleagues
for all known species. This hypothesis was later
substantiated by our group in collaboration with
Yuichi Oba (Japan).
Do you think your findings will help to create
glowing plants or trees as an alternative light
source like the work being carried out by Alexander
Krichevsky and his company?
Gleaux is using bacterial bioluminescent system
in its applications. I believe our system is more
suitable for plants, as the fungal luciferin precursor,
hispidin, commonly occurs in various plants and
consequently is not only non-toxic to them, but,
more importantly, could be biosynthesized in plants.
Do you think we will we ever be able to put our
Christmas lights in the bin and buy a self-lighting
Christmas tree?
Sure, I believe that in a couple of years we will
have bioluminescent plants available for research
purposes, and I’m pretty sure self-luminous
Christmas trees will shortly follow. Moreover,
I think that this new biotechnology will be based on
fungal bioluminescence.
■
Further reading
1. Krichevsky A, Meyers B, Vainstein A, Maliga P,
Citovsky V (2010) Autoluminescent Plants. PLoS ONE
5(11): e15461. http://dx.doi.org/10.1371/journal.
pone.0015461
2. Gleaux website http://gleaux.us/welcome-to-gleaux/
3. Purtov K.V., Petushkov V.N., Baranov M.S. The
Chemical Basis of Fungal Bioluminescence. Angew
Chem Int Ed Engl. 6; 54(28):8124-8128. http://dx.doi.
org/10.1002/anie.201501779
December 2016 © Biochemical Society 33
Historical Feature
Fatty acids and feminism: Ida
Smedley MacLean, the first woman
to Chair the Biochemical Society
Robert Freedman
(University of Warwick, UK)
In 2017, Professor Anne Dell will take over as Chair of the Biochemical Society. She is only the
fourth woman to hold that office in more than 100 years, with the first of her predecessors
taking up the office 90 years ago in 1927! Fostering diversity and equal opportunity is one of
the Society’s strategic objectives. Having inclusivity as a norm – and an expectation on the part
of our members and community – would not have been possible without the pioneering role
of women such as Ida Smedley MacLean.
Ida Smedley MacLean (1877–1944) was a remarkable
woman – a first-wave feminist with significant
achievements in science and a unique record among
women of her generation as leader in the scientific
world and in women’s organizations. She tackled
barriers head on, campaigning against formal
obstacles and exclusions, being the first through
the opening when the walls were breached and then
demonstrating that, as an extremely competent
woman, she could play a full part alongside men in
the normal work of the scientific community. But,
in parallel, she saw a need for women to network in
order to gain confidence and a need for organizations
to support networking and campaigning.
Ida Smedley was born in Birmingham into a
progressive, cultivated and well-off family. During
Ida’s childhood, her mother kept a ‘salon’ at the
family home to which the literary and musical
elite of Birmingham society came. At age 9, Ida
was sent to King Edward VI High School for Girls
in Birmingham. The school was then quite new
(founded 1883), but soon to gain a real reputation
for science teaching. The head and science teachers
were from the first generation of women to study at
Newnham College, Cambridge, and Ida was part of
a cohort of girls who progressed from the school to
Newnham to study and forge careers in science.
Ida entered Newnham in 1896 when women
had been studying in Cambridge for over 20
years, although their position was informal. In
May 1897, an attempt was made to regularize the
position so that women students could be awarded
degrees. Opponents of this move mobilized and
the proposal was heavily defeated. Triumphant
male undergraduates celebrated by rioting, hanging
effigies of women students and constructing a huge
bonfire in central Cambridge 1. So at the time when
34 December 2016 © Biochemical Society
Ida might first have imagined herself a member of
the academic and scientific community, she had a
very stark reminder of the barriers to such a career.
Following on from her undergraduate studies,
Ida moved between London and Cambridge
supported by scholarships and temporary teaching
roles, ultimately being awarded a DSc (Doctor of
Science) from the University of London for research
in classical organic chemistry. During this period,
she raised a petition for the admission of women to
the Chemical Society 1. The petition noted that in the
30 years from 1873, the Chemical Society’s journals
had published 300 papers by 150 women authors.
But the petition failed, as did various subsequent
attempts until 1920.
In 1906, Ida was appointed Assistant Lecturer
in Chemistry at Manchester University. She was the
first woman on the academic staff of the Chemistry
Department and made some strong friendship links
there, but was frustrated by trivial obstacles; she
could not speak at the student Chemical Society
since women could not be members and in any case
the Society held its meetings in the Student Union
building which excluded women! This rebuff may
have prompted Ida to her next initiative.
In March 1907, she convened a meeting at
Manchester High School for Girls of 17 university
and professional women to consider a proposal
for establishing a Federation of University Women
with aims including ‘…to work for the removal of
sex disabilities, to facilitate the communication and
co-operation of university women and to afford
opportunity for the expression of a united opinion
by university women…’ 2. This was the beginning of
the British Federation of University Women (BFUW)
which, within two years, had active groups across
the UK; it became a very effective networking and
Historical Feature
lobbying body for working women graduates and for
female academics.
Soon after, Ida was the first woman to be
awarded a Beit Research Fellowship, a prestigious
and well-funded personal fellowship and, in early
1911, she moved to the Lister Institute of Preventive
Medicine in London to take up this award and begin
her lifetime work on fats and fatty acids. This move
enabled her to move into biochemistry (the Lister
in the early 20th century was the leading centre
in Britain for the new sciences of biochemistry,
microbiology, immunology and nutrition) and
to move from the demands of teaching and the
rule-bound conservatism of a big university into a
dedicated, privately funded research environment,
with a supportive director and helpful colleagues.
In her first years at the Lister, Ida analysed the
chemical structure of fatty acids in butter and other
sources, showing that they were exclusively straight
chains containing even numbers of carbon atoms3. She
also published an important theoretical paper4 proposing
a mechanism by which fatty acids could be built up
from smaller components derived from carbohydrates.
She proposed a chemically plausible precursor (pyruvic
acid) and a chemically plausible mechanism in which
fatty acid chains were built up and elongated two carbon
atoms at a time. This work gained her an international
reputation and she was awarded prizes as well as being
mentioned in newspaper reports on women scientists
alongside Marie Curie and Marie Stopes. Of course it was
many years later, after her death, that this mechanism
was finally confirmed and coenzyme A identified as the
carrier of the active 2-carbon intermediate.
Also in 1911, Ida began to play golf and collaborate
with a physician carrying out research at the Lister,
Hugh MacLean. Their skills were complementary – he
the physiologist, she the analytical chemist – and they
jointly published studies on the metabolism of sugars
by organs such as the heart and liver5. They were
married in 1913 and had two children, a son (b. 1914)
and daughter (b. 1917). Hugh was later appointed to
senior academic medical posts at St Thomas’ Hospital.
During the next few years, Ida was considered
for Readerships and Chairs at London University
and it is not clear whether the Search Committees
reconsidered when they realized Ida was pregnant
for the second time, or whether she turned them
down, preferring to stay at the Lister 6.
By this time, the BFUW was well-established
across the country with more than 1000 members.
Between the wars, its energies had four major
targets7: i) opportunities and barriers for women in
academia, ii) the situation of women graduates in the
working world, especially in teaching, medicine and
the Civil Service, where women were often required
Ida as an undergraduate
to resign on marriage, iii) collecting statistics bearing
on women’s university education and progression
into work and iv) providing ‘club’ facilities for
working women where they could meet colleagues,
have a meal, possibly stay overnight in the kind of
congenial atmosphere that professional men enjoyed
through ‘gentlemen’s clubs’.
Ida was involved in every aspect of the
Federation’s work serving as Secretary long term and
then as President (1930–1935). She had a particular
interest in raising money for research scholarships
and fellowships, and she was clearly good at business
of all kinds, both handling committees and making
practical and commercial decisions. Her (women)
colleagues at the Lister, in their history of the
laboratory8 comment on her ‘She was indeed one of
those who earned the enfranchisement of women in
this country not by militancy but by evoking sheer
respect of their capacities.’
In 1918, contacts began between the BFUW and
its US counterpart and these bodies met in London
in 1919 to found the International Federation of
University Women. The IFUW was a great success;
by 1930 it united 24,000 academic women and
graduates from 30 countries. Ida had instigated
an IFUW International Travelling Fellowships
Programme, had fundraised and for most of the
inter-War period chaired the committee that
administered this programme. But all international
organizations were challenged by the rise of fascism
and Nazism; the dismissal of Jews and regime
December 2016 © Biochemical Society 35
Historical Feature
Structure of arachidonic acid
Ida in 1930 as Chair of the British Federation of University Women
opponents from academic positions in Germany and
elsewhere led to personal crises as academic women,
often responsible for the care of elderly parents,
had to make decisions on whether to emigrate9. Ida
was active personally and through the federations
in assisting the resettlement of academic women
refugees in England.
At the same time she was playing a full part
in the machinery of the scientific community in
Britain. Having been involved since 1904 in repeated
campaigns for the admission of women to the
Chemical Society, she was one of the first women
admitted (1920) and was the first woman elected
to the Chemical Society Council (1930–1931).
Similarly, she was one of the first three women
elected to the Biochemical Society (1913), and was
then the first woman on our Council (1920) and our
first woman Chair (1927–1928).
Through the 1930s, Ida was still active in research
at the Lister and this period led to her second key
research achievement. It was known that rats fed on
a defined diet lacking fats, but with plentiful calories
and protein and supplemented with vitamins A and
D, failed to thrive. This ‘fat-deficiency disease’ could
be reversed by small doses of natural oils and fats.
36 December 2016 © Biochemical Society
Ida investigated this through the 1930s in complex
feeding experiments, refining the nature of the
essential components absent from the fat-free diet
and also analysing the small amounts of fat stored in
these lean and fat-deprived animals. She identified
linoleic and linolenic acids as the essential dietary
fatty acids, and showed that these could be converted
in vivo into the more complex 20 C polyunsaturated
fatty acid, arachidonic acid, the precursor of the
prostaglandins10–12. Finally, in 1940, just when
the Lister was being evacuated from London to
Cambridge to avoid bombing, she published the
correct full structure for arachidonic acid including
the positions of the double bonds13. This work was
recently celebrated in a review in the Journal of Lipid
Research14 which highlighted the small quantities of
material that Ida and her collaborators had to work
with and the use of entirely traditional techniques,
with no modern spectroscopy.
Ida also had serious personal commitments too!
In 1930, her husband had a mental breakdown which
incapacitated him for over 4 years, so that Ida had
to organize residential care and, later, manage his
rehabilitation when he returned home – at a time
when she had two teenage children attending day
schools in London. Her diaries from the 1930s15 are
full of references to attending cricket and football
matches involving her son, Kenneth, and to shopping
expeditions with her daughter, Barbara. And, in her
1938 diary, she records nipping out at lunchtime
from a Royal Society meeting on proteins, after a
talk by Svedberg, in order to find material for the
lining of her husband’s overcoat! The demands on
Ida of work, public life and family life make her a
very recognizable modern female scientist.
■
I am very grateful to Dr Ida Smedley MacLean’s
granddaughter for making unpublished materials and
photographs available to me.
Historical Feature
Timeline :
1877: Born on 14 June in Birmingham.
1896: Joins Newnham College, Cambridge.
1899: Enrols in London School of Medicine for Women.
1901: Switches to chemistry, with a Bathurst Studentship
at the Central Technical College, London.
1906–1910: Serves as Assistant Lecturer in Chemistry at
Victoria University, Manchester.
1910: Awarded Beit Memorial Fellow at the Lister Institute.
1913: Marries biochemist Hugh Maclean.
1918: Appointed as a Fellow of the Institute of Chemistry.
1919, 1929–1935: Serves as President of the British
Federation of University Women.
1927: Shares credit with (husband) Hugh Maclean for the
2nd edition of Lecithin and Allied Substances.
1927–1928: Becomes the first woman to become Chair of
the Biochemical Society.
1931–1934: Becomes the first woman on the Council of
the London Chemical Society.
References
1. Rayner-Canham, M. and Rayner-Canham, G. (2008) Chemistry was their Life:
Pioneer British Women Chemists 1880–1949. Imperial College Press, ISBN-13 978-186094-986-9
2. Sondheimer, J.H. (1957) History of the British Federation of University Women
1907–1957. The British Federation of University Women, pp. 52
3. Smedley, I. (1912) The fatty acids of butter. Biochem. J. 6, 451–461
4. Smedley, I. and Lubrzynska, E. (1913) The biochemical synthesis of the fatty acids.
Biochem. J. 7, 364–374
5. MacLean, H. and Smedley, I. (1913) The utilisation of different sugars by the normal
heart. J. Physiol. 45, 462–469
6. MacLean, B.D. (1997) Some Midland Ancestors. Unpublished memoir
7. Dyhouse, C. (1995) The British Federation of University Women and the Status of
Women in Universities 1907–1939. Women’s History Review, 4, 465–485
8. Chick, H., Hume, M. and Macfarlane, M. (1971) War on Disease: A History of the
Lister Institute. Andre Deutsch, ISBN 0 233 96220 4, p. 166
9. von Oertzen, C. (2014) Science, Gender and Internationalism: Women’s Academic
Networks, 1917–1955. English translation by K. Sturge. Palgrave-Macmillan, ISBN
978-1-137-43888-1
10. Hume, E.M., Nunn, L.C.A., Smedley MacLean, I. and Smith H.H. (1938) Studies of the
essential unsaturated fatty acids in their relation to the fat-deficiency disease of
rats. Biochem. J. 32 2162–2177
11. Nunn, L.C.A. and Smedley MacLean, I. (1938) The nature of the fatty acids stored by
the liver in the fat-deficiency disease of rats. Biochem. J. 32, 2178–2184
12. Smedley MacLean, I. and Nunn, L.C.A. (1938) Fat-deficiency diseases of rats: the
effect of doses of methyl arachidonate and linoleate on fat metabolism, with a
note on the estimation of arachidonic acid. Biochem. J. 34, 884–902
13. Dolby, D.E., Nunn, L.C.A. and Smedley MacLean, I. (1940) The constitution of
arachidonic acid (preliminary communication). Biochem. J. 34, 1422–1426
14. Martin, S., Brash, A.R. and Murphy, R.C. (2016) The discovery and early structural
studies of arachidonic acid. J. Lipid Res. 57, 1126–1132
15. Smedley MacLean, I. (1933, 1934, 1938). Unpublished personal diaries
1932: Appointed to the staff of the Lister Institute.
1943: The Metabolism of Fat published.
December 2016 © Biochemical Society 37
Science Communication Competition
The Science Communication Competition is now in its sixth year. As in previous years, it aims to find young talented science writers and give
them the opportunity to have their work published in The Biochemist. In 2015, a new branch of the competition was launched to include video
entries. Overall this year’s competition attracted 62 entries and these were reviewed by our external panel of expert judges. The third prize in
the written category was awarded to Jessica Hardy from the University of Oxford, whose article is presented here; the third prize in the video
category went to Johanna Laibe from Kingston University.
Johanna’s video can be viewed on the Society’s YouTube channel: http://bit.ly/2c2dFmB
Cancer: a disease of bad
luck, or bad lifestyle?
Jessica Hardy
(University of Oxford, UK)
Cancer. It’s an emotive word, and a dreaded diagnosis. We all know someone affected by this
horrible disease, and quite understandably, we all want to know: what causes cancer, and is
there anything we can do to stop ourselves from getting it?
This is one of the most burning public health
questions of modern times, but it’s pretty difficult to
find a clear answer. Take these two headlines, both
published on the BBC News website in 20151,2, and
both based on scientific studies:
Headline 1: Most cancer types ‘just bad luck’.1
Headline 2: Study suggests cancer is not ‘just
bad luck’. 2
So, which one is it? Can we throw caution to the
wind, keep the 40-a-day smoking habit and indulge
38 October 2016 © Biochemical Society
in a daily fry-up, knowing that our risk of getting
cancer is beyond our control? Or, can we completely
eliminate our cancer risk by filling our lives with
superfoods and daily workouts?
As you’ve probably guessed, the answer lies
somewhere between these two extremes. There is
clearly some element of ‘bad luck’ in developing
cancer. Take Joe and Mike, who are both 61. Joe has
never smoked, but sadly he’s just been diagnosed
with lung cancer. Mike has smoked heavily for 45
years, but remains healthy. This might seem unfair,
and supports the idea that Joe’s cancer is ‘just bad
luck.’ However, it’s well-established that smokers
Science Communication Competition
are much more likely to develop lung cancer than
non-smokers and it would be unwise to completely
dismiss the influence of lifestyle on cancer risk.
But just how much of cancer is about bad luck,
and how much control do we really have? To tackle
this question, it’s important to understand how
cancer develops. Cancer is, in short, a disease caused
by excessive division of cells. Cells are the functional
building blocks of our tissues and organs, and in
order to grow, and to repair or replenish parts of
these tissues, we need to be able to make new cells.
Our bodies do this by using existing cells as templates
for new ones, in a process called cell division.
However, if cells divide when it’s unnecessary, this
can be problematic. It can lead to an overgrowth of
cells, forming a tumour – a mass of rogue cells which
don’t work properly, and which disrupt the function
of the affected organ. Left unchecked, these deviant
cells ultimately evolve the ability to spread within the
body and seed new tumours, eventually damaging
vital organs and causing death.
The question is, then, what makes cells start to
misbehave and divide when they shouldn’t? The key
lies in our DNA. Every cell contains a genetic code,
made of a chemical called DNA, which contains the
instructions that make the cell work correctly. This
includes, for example, the code to make molecules
which regulate cell division. The problems begin
when this code is altered in some way – a process
called mutation. Mutation can be thought of as
miscopying or changing the code, much as someone
might make a mistake when typing up a handwritten
document. Let’s imagine a secretary, Bruce, typing
up some meeting notes. He’s usually very accurate,
but occasionally a mistake creeps in. This might
be harmless, and might not change the meaning of
the sentence. For example, he might type ‘We must
not DISPOZE of hazardous waste in the yellow bin’
instead of ‘We must not DISPOSE of hazardous
waste in the yellow bin’. Ok, he misspelt a word,
but it doesn’t really matter. Sometimes, though, the
mistake might have dangerous consequences. He
might type ‘We must NOW dispose of hazardous
waste in the yellow bin’, rather than ‘NOT’. That will
cause trouble! The same can be said for copying the
DNA code into a new cell during cell division. When
representing the DNA code, we use 4 letters – A, T, C
and G - to signify the 4 chemical bases of DNA. A ‘T’
in the code could, for example, be miscopied as a ‘C’.
Depending on which part of the code is affected, this
may have little effect on the instructions, or it might
completely change the behaviour of the new cell.
These DNA mutations happen very occasionally,
by chance, every time a cell divides. This represents
the ‘bad luck’ aspect of cancer. If enough chance
mutations accumulate in important places in the
DNA, enough instructions might be changed
to make a cell divide continually or develop
characteristics that support tumour growth – the
so-called ‘hallmarks of cancer’3. However, there
are many factors which can increase the chance of
these mutations arising. Let’s consider Bruce’s typing
again. If he types his notes after having a few pints
of beer, or after getting only 2 hours of sleep, he’s
much more likely to make mistakes. Analogously,
smoking, the most notorious risk factor for cancer,
greatly increases the chance of DNA mutations, as
the chemicals in cigarettes can directly react with
DNA, leading to changes in the code. Equally, too
much sun exposure greatly increases skin cancer
October 2016 © Biochemical Society 39
Science Communication Competition
risk, because UV light induces chemical reactions
within DNA that can alter the code.
You may be wondering why then, if we understand
how mutations can arise and lead to cancer, there are
still such conflicting reports on how much of cancer
is ‘bad luck’.
The article entitled ‘Most cancer types ‘just bad
luck’’1 was based on a study which addressed the
question of why some organs, like the bowel, are
more prone to cancer than others, like the brain 4.
The researchers found that this was partly explained
by the number of dividing stem cells in each organ.
The bowel is constantly renewing its lining, and
therefore has lots of cell division, whilst brain cells
divide much less frequently. More cell division
and copying of the DNA means more chance for
mutations to be introduced by miscopying. The
authors used mathematical models to show that
around two-thirds of the variation in cancer rates
between organs is explained by differences in stem
cell division rates, and therefore suggested that
‘random’ mistakes in DNA copying during stem cell
division are the underlying cause of the majority of
cancers4.
Unfortunately, the media headline that ‘most
cancers are bad luck’ led many to announce with
delight that they could keep their unhealthy habits
and stop worrying. Whilst this bold headline may
have had some element of evidence backing it, being
based on the two-thirds figure from the study, it
overlooks the quite significant one-third that ARE
seemingly influenced by external factors. It also
ignores the important suggestion that environmental
factors might contribute to these seemingly ‘random’
mutations that accumulate during cell division.
In fact, another study, which analysed some of
the same stem cell division data 5, led to the second
headline – ‘Study suggests cancer is not ‘just bad
luck’ 2. This study argued that just because a tissue
with more cell division is more prone to cancercausing mutations, it doesn’t mean that these are
‘random’ mistakes. Environmental factors could
easily contribute to mistakes made during cell
division, just as they can cause mutations in nondividing cells. The researchers used different
mathematical models based on this idea, and also
looked at the types of mutations found in different
cancers to try and figure out what proportion look
like those often caused by external factors. Their
analysis, contrary to the first study, suggested that
40 December 2016 © Biochemical Society
only 10-30% of cancers are due to ‘random mistakes’,
with the majority involving some lifestyle influence5.
You might ask how two rigorous scientific studies
can give such different conclusions. The reality is, the
maths is complex – the groups constructed different
mathematical models based on slightly different
assumptions and predictions in order to analyse the
available data. The real answer may be somewhere
between these two figures, and as we research more
into the factors which promote DNA mutation and
cancer growth, these models and estimates will
continue to improve. But one thing is for sure –
there is certainly SOME, probably fairly significant,
contribution of environmental factors to our risk of
developing cancer.
The take-home message is that nobody is immune
to cancer. DNA mutations will happen – it is a fact
of life. And sometimes, although thankfully rarely,
a particularly unfortunate cocktail of mutations
may arise which leads to cancer developing. There
is nothing we can do that will guarantee this won’t
happen. However, we can certainly stack the odds
in our favour and drastically reduce the frequency
of these mutations and the chance that cancer will
develop. Research is continually improving our
understanding of which lifestyle factors contribute
to cancer development, and although we are still
bombarded with confusing and sometimes conflicting
reports on what we should and shouldn’t do, there
are some very well-supported recommendations, as
detailed by Cancer Research UK6: don’t smoke, drink
less alcohol, eat lots of fruit and vegetables, maintain
a healthy weight and avoid excessive sun exposure.
It might sound boring, but these really are some of
the best things you can do to try and minimise those
risky mutations!
■
References
1. Gallagher, J. (2015) http://www.bbc.co.uk/news/
health-30641833
2. Gallagher, J. (2015) http://www.bbc.co.uk/news/
health-35111449
3. Hanahan, D. and Weinberg, R.A. (2011) Cell 144, 646-674
4. Tomasetti, C. and Vogelstein, B. (2015) Science 347,
78-81
5. Wu, S., Powers, S., Zhu, W. and Hannun, Y.A. (2016)
Nature 529, 43-47
6. Kirby, J. (2011) http://scienceblog.cancerresearchuk.
org/2011/12/07/the-causes-of-cancer- you-can-control/
Policy Matters
Tackling the AMR crisis – a global approach
Gabriele Butkute (Science Policy Officer, Biochemical Society)
Earlier in the year, Lord Jim O’Neill wrote a Review
on antimicrobial resistance in which he set out a
comprehensive action plan for the world to tackle
antimicrobial resistance (AMR). According to the
Review, AMR could kill 10 million people a year
by 2050, the equivalent of 1 person every 3
seconds; more than cancer kills today.
The success of the action plan’s
implementation depends on global
cooperation
and
coordination,
which is why on 21st September
2016, all 193 countries of the UN
signed a declaration agreeing to
take action against antimicrobial
resistant infections.
There is no one solution to AMR
as several different concerns need to
be addressed, including, improving
hygiene, reducing unnecessary use of
antimicrobials in agriculture, advancing
global surveillance and developing new
rapid diagnostics.
Raising public awareness on AMR is key
to tackling the issue. UK members of the European
Federation of Biotechnology in association with the
Learned Society Partnership on AMR (LeSPAR)
organized a discussion evening on 10 October, during
Biology Week 2016, to debate how regulation and
innovation can help tackle the antimicrobial resistance
crisis. A panel of expert speakers from across the life
sciences included: Professor Mark Fielder, Vice President
of the Society for Applied Microbiology, Tamar Ghosh, Longitude Prize Lead at Nesta,
John Broughall, volunteer with Antibiotic Research UK and Professor Jeff Cole, Vice
President of the European Federation of Biotechnology.
The audience shared their experiences of
different prescription practices across Europe
– Norway was said to be more stringent
than many others and antibiotics there
weren’t readily available without
conclusive diagnostic tests. The use
of antibiotics in agriculture was
also widely discussed. Professor
Mark Fielder said that in the
USA up to 70% of antibiotic
consumption was non-human
because the drugs increase
animal growth and meat yields by
10%. He added that antimicrobial
resistance is a complex issue where
the human and animal health is
closely interconnected with their
environment (for example, it is said that
the antibiotics in sewage contaminate the
surrounding and further contribute to AMR).
While the discussions on AMR usually revolve
around resistance, there is another angle to keep in mind Tamar Ghosh reminded the audience that although we are in the midst of an AMR
crisis, more people are dying worldwide from a lack of access to antibiotics than
from AMR-related issues.
■
Biochemical Society is a member of the European Federation of Biotechnology and the
Learned Society Partnership on ARM (LeSPAR).
Summary
Nuffield Council on Bioethics publishes a review on genome editing
Genome editing: an ethical review sets out our preliminary findings on the
impact of genome editing across different areas of biological research and
the range of questions it raises. The review has identified top two ethical
challenges for genome editing application – preventing inherited genetic
diseases and increasing food production rates in farmed animals. Further
work by Nuffield Council on Bioethics will be carried out on each of these
two areas, focusing on recommendations for policy and practice, and will
be published in 2017.
Gathering evidence on the impact of Brexit on higher education
The House of Commons Education Select Committee launches an inquiry
into the impact of UK’s exit from the European Union (EU) on higher
education. The consultation includes but isn’t limited to: the impact of
Brexit on EU students studying in England, the future of the Erasmus
programme, risks and opportunities for UK students and the steps the
Government should take to mitigate any possible risks and take advantage
of any opportunities following Brexit. The Society will be feeding into the
Royal Society of Biology’s response.
To find out more about our science policy work, please email Gabriele Butkute (Science Policy Officer) at [email protected]
December 2016 © Biochemical Society 41
Learning Curve
Is AMR the new climate change?
Anastasia Stefanidou
(Communications Officer,
Biochemical Society)
Antimicrobial resistance (AMR) has the potential to affect everyone and it cannot be taken lightly.
Drug resistant infections must be addressed as a priority, particularly in light of projections that 10
million people a year will die by 2050 if the problem isn’t tackled now.
On 21 September, the UN General Assembly gathered
world leaders and made a commitment to work at
national, regional, and global levels to address the growing
threat of AMR. Representatives from 193 countries
signed a declaration to ‘Act on AMR’, signalling a strong
commitment to curb the global overuse of medicines to
treat disease.
Many people fear that the AMR problem is going to
end up like climate change. The issue of climate change
was raised in the late 80s and early 90s, over the past 30
years it has been challenging to agree collective action. We
are still in a position where many people doubt whether
climate change is a real problem and if that’s the model
that AMR is going to follow then we should all be worried.
To raise awareness of the issue, the Biochemical
Society and the Microbiology Society collaborated to
hold a panel discussion at the New Scientist Live event
on Saturday 24 September 2016, which was attended by
600 people.
Laura Bowater, Senior Lecturer at the University of
East Anglia, chaired a panel which included Anthony
McDonnell, Head of Economic Research for the Prime
Minister’s Review on Antimicrobial Resistance, Tamar
Ghosh, lead on Nesta’s (http://www.nesta.org.uk) initiative
– the Longitude Prize, to solve antibiotic resistance, and
Caroline Barker, Honorary Senior Lecturer at University
of East Anglia.
Barker opened the event presenting the clinicians’
perspective. “We are dependent on antibiotics for
successful transplant procedures or to help cancer and
arthritis patients”, she said. “So we need good effective
antibiotics because when we start seeing problems with
resistant bacteria it means that these patients are very
much in danger”.
Through her 30 years of experience, Barker has seen
that the NHS is dealing with more and more resistant
microorganisms caused by overuse of antibiotics.
She outlined the key things that she believes are
needed to tackle this problem:
• New, affordable drugs – as we are running out of
effective antibiotics
• Different approaches to killing bacteria – e.g. using
bacteriophages, viruses that kill bacteria, or looking
at new ways of targeting the poisons that cause the
disease process.
Next, McDonnell introduced his work for the Prime
Minister’s Review on Antimicrobial Resistance.
42 December 2016 © Biochemical Society
The Review was set up two years ago by the then
Prime Minister, David Cameron, who appointed
the economist Jim O’Neil to analyze the global
problem of AMR and propose actions to tackle
it internationally.
The team commissioned two multidisciplinary
research teams from research institute RAND Europe and
consultancy KPMG, each to provide their own assessments
of the future impact of AMR, based on scenarios for rising
drug resistance and economic growth to 2050. Their
results project that if resistance is left unchecked, the loss
of world output will get bigger through time, so by 2050,
the world will be producing between 2 and 3.5% Gross
Domestic Product (GDP) less than it otherwise would.
Furthermore, 10 million more people would be expected
to die every year than would be the case if resistance was
kept to today’s level.
The second challenge was “How do you solve AMR?”
which prompted 10 solutions:
‘Tackling antimicrobial resistance on ten fronts’ by Review
on Antimicrobial Resistance (https://amr-review.org/
infographics) available under CC BY 4.0 license
Learning Curve
Ghosh then introduced the Longitude Prize, UK’s
biggest science prize in field of rapid diagnostics for drug
resistant infections.
In May 2014, 300 years after the original Longitude
Prize, Astronomer Royal Lord Martin Rees, decided
to revive it. The Longitude Committee shortlisted six
challenges facing the world and the British public had
the opportunity to vote for the one they thought should
become the focus of Longitude Prize through BBC2’s
Horizon programme and they chose AMR.
The vision of the Longitude Prize is to significantly
reduce the overuse or misuse of antibiotics. Nesta
decided to ask teams around the world to develop a
transformative, point-of-care diagnostic test that will
allow health professionals worldwide to administer the
right antibiotics at the right time. The goal is to identify a
test that is accurate, affordable, can be used anywhere in
the world in any health system and needs to give a result
in less than 30 minutes. So far, 205 teams in 39 countries
are working towards this.
Presentations were followed by a panel discussion
led by Laura Barker. Some key questions were:
What can we learn from the past?
Barker noted that: “There are important public health
lessons to learn from the past. For example, we know that
good sanitation improved recovery rates from infectious
diseases and we know that immunization has helped
prevent them.
There are things we can do, like not putting
antibiotics into our food chain, and we need to make
sure that all of our health professionals are up to speed
with preventing these organisms spreading from patient
to patient.
Public health, infection control, public understanding
and public education are very important, because if we can
prevent these infections from spreading then we won’t have
to start throwing ever more antibiotics after the problem.
We are all responsible for our own health and adapting
our behavior to prevent us from getting these infections is
very important”.
Ghosh added: “We did some surveys to understand
what the awareness is amongst the UK population.
We found that 38% of the public still do not know that
antibiotics are only effective for bacterial infections.
We really need to make sure that people know exactly
when they should be taking them. So we need to change
behaviors like:
• Buying antibiotics over the counter (outside the UK)
or on the internet
• Sharing antibiotics
• Storing antibiotics ‘for the next time we get sick’”.
‘The journey from idea to award’ by the Longitude Prize (https://longitudeprize.org/)
It seems that there is going to be a bigger problem in the poorer parts of the
world, the developing nations. Do we really to worry about it here?
McDonnell said: “Yes we do! While it might be a bigger problem in India, it’s still
going to be pretty terrible here.
We already lose 3000–4000 people from this in the UK every year. If that goes up to
30,000–40,000 or moves to children (because at the moment, it’s mostly people towards
the end of their lives) then you will really start to notice it in the UK”.
Barker added: “Remember that with increasing global travel what happens to other
parts of the world soon ends up in our backyard too.
Diseases don’t stay where they start, they travel the world. And a lot of multi-resistant
organisms we’ve seen in clinical practice research recently have originated in India and
China but ended up here. So we cannot just say that’s just somebody else’s problem, that
problem is going to pitch up on our doorsteps sooner or later”.
Bowater reminded us that “It’s not just scientists and economists that are part of the
solution, but everybody”. And summed up: “Solutions have to be happening on lot of
different fronts in order to ameliorate the scenario of losing ten million people to antibiotic
resistance in 2050. We shouldn’t just be relying on doctors to stop prescribing. We should
be looking into pharma taking part to start thinking about getting better antibiotics and
investing in production. We also now have a prize to look for better diagnostics and we
need to do this because there is no point in pharma creating antibiotics if we are not
looking after them properly when we get them. Finally, we have to rely on members of
public to understand that antibiotics are an absolutely precious resource that we need to
look after and that we are all responsible for”.
The take home message from the event was: “Be inspired! Go away, do your bit!
AMR is in your hands!”
■
The Biochemical Society would like to thank our brilliant chair and speakers for taking part in
this event, the New Scientist Live team and the Microbiology Society for hosting the debate.
December 2016 © Biochemical Society 43
News
Royal Society of Biology News
Celebrating Biology Week and taking life science to Parliament
Dr Mark Downs CSci FRSB
(Chief Executive, Royal Society
of Biology)
In October we celebrated the fifth annual Biology Week
with life science celebrations happening all over the UK,
including many biochemistry events and activities. The
Learned Society Partnership on Antimicrobial Resistance
(LeSPAR) of which the The Royal Society of Biology
(RSB) and the Biochemical Society are members, held a
popular Policy Lates event on antimicrobial resistance.
Participants examined the roles of innovation and
regulation in tackling the AMR crisis from different
perspectives, including veterinary research, biotechnology
and public health. RSB and the Biochemical Society also
organised the Biology Week debate, in partnership with
Cancer Research UK. The questions up for discussion:
Can we predict people’s chance of getting cancer? Should
we? attracted hundreds to the Royal Institution to discuss
the latest screening and genome sequencing techniques,
along with the ethical and societal impact of ‘The DNA
Revolution’. An audio recording of the event are available
on the RSB website now.
This year we have also run several public
engagement activities for a general audience, in
partnership with the Biochemical Society and our
other Membership Organisations (MOs). In June
the ‘Biology Big Top’ went to Cheltenham Science
Festival and the Big Bang Fairs in Yorkshire and
Humber, and in July we were at Lambeth Country
Show. Jointly developed activities as part of ‘The
Hungry Games’ engaged thousands of people from
all backgrounds with issues around food security,
nutrition, agriculture, food waste and sustainability.
Early in the new year we hope to start working with
our MOs on the annual Voice of the Future event. At
Voice of the Future, young scientists and engineers
quiz key political figures in the Houses of Parliament
Biology Big Top at Cheltenham Science Festival
44 December 2016 © Biochemical Society
about the science policy issues that matter to them. It
is a unique event – in no other part of Parliament is the
normal select committee format completely reversed
so that MPs have to answer questions rather than ask
them. The event aims to highlight the importance
of policy makers using reliable evidence and being
held to account on their decisions and today’s young
scientists will be vital for this in the future. Last year
the Biochemical Society sent along young career
researchers who asked the committee, including
Science Minister Jo Johnson MP, questions such as:
‘How important is scientific advice measured against
other forms of evidence in arriving at policy decisions?’
The Drug Discovery Pathways Group, or DDPG,
is a partnership of learned societies including RSB
and the Biochemical Society that has provided a single
well-informed and representative voice on key issues
associated with medicines research. The Group’s work
has focussed on three main areas: industry-academia
partnerships, knowledge and skills.
The DDPG has actively sought to influence the
policy environment and offer proactive proposals to
support drug development. This has included a push
to create better cross-sector exchange of information,
people and knowledge through mechanisms such
as a Drug Discovery Advisory Forum that could
bring together medical charities, funding bodies,
businesses, academics, the NHS and learned societies,
to ensure patients’ needs are met in a sustainable and
cost-effective manner, and that the UK remains at
the forefront of medicines research. There has been
significant movement in this direction over the last
five years and the DDPG is now considering how best
to evolve its own objectives.
■
Policy Lates on AMR
Book Reviews
The Society of Genes
Itai Yanai and Martin Lercher (2016) Harvard University Press,
£20.95 ISBN: 9780674425026
The Society of Genes moves us forward in our
thinking on how genes, proteins and molecules
in a living organism act in concert to bring
about a fully functional collection of cells we
call an organism. While homage is paid to
The Selfish Gene by Richard Dawkins and its
ramifications, the book evolves to encompass
a more collegiate and all-inclusive molecular
society where genes and proteins interact
and interplay with one another to fulfil their
societal destinies. The Society of Genes does
not offer radical or novel concepts in molecular biology or genetics, but
it does assemble some interesting stories and facts on how our genes
act with one another to bring about distinct genotypes and phenotypes.
The book covers a diverse array of topics including, amongst others,
the eight steps of cancer progression, bacterial and viral enemies,
language and speech development and transposable elements. Rather
confusingly, the chapter titles do not adequately reflect these topics.
Non-scientists or the general reader (the books main audience) would
have difficulties in deciphering the true meaning of chapters, at a
glance. Some chapter titles include “The Clinton Paradox” (Evolution)
and “The Chuman Show” (Origin of the Species). Similarly, when
delving into such chapters, it was difficult to truly decipher what
exactly the chapter was about, as the reader had to wade through
overly verbose paragraphs and some longwinded explanations.
However, if the reader uses the book as a reference manual
and focuses exclusively on the index, then quite a few interesting
concepts come to the fore. Most molecular biologists worth their
salt will be familiar with Clustered Regular Interspersed Spaced
Palindromic Repeats (CRISPR) gene editing technology. The
authors explain this system, referencing heritable variation and
natural selection in the context of bacterial variability.
Similarly, the story of FOXP2 is explained well and will appeal to
the general audience. Cited as a pivotal player (manager) in language
and speech formation, the authors explained how the gene was
identified and characterised using both mammalian and bird studies.
Likewise, “The Rotting Ship of Theseus” refers to the pleiotropic
effects of our genes; the metaphor plays on how a rotting plank affects
adjacent planks, thereby affecting the entire ship. These examples,
to name but a few, reinforce the main thrust of the book, that our
genes are woven into an extraordinary complex society that function
collectively as a unit.
This book is aimed at a lay audience and as such would not appeal
to established cell and molecular biologists and geneticists well
versed in the tenets of the molecular sciences. In some places, the
writing can come over slightly patronising and condescending, even
to the lay audience. A thorough edit would have eliminated much of
the excessive prose and greatly reduced paragraphs to bite-sized but
manageable sections. Likewise, some figures were incomprehensible,
this reviewer had to focus hard to decipher their true meanings.
Genes existing as a society is both a plausible and no-doubt
accurate reflection of our molecular makeup. While not representing
the paradigm model, the book dovetails neatly with “The Selfish
Gene” and acknowledges that within every society, there are
individuals (genes) with purely solipsistic motives. However,
precisely where this ends and starts is undoubtedly another book.
The Society of Genes will have huge appeal to schools and colleges
with a broad science curriculum and will no-doubt provide topical
debate on the exact role of our genes.
John Phelan (University College Cork, Ireland)
December 2016 © Biochemical Society 45
News
Meeting Reports
British Yeast Group Meeting 2016
29 June –1 July, 2016, Swansea University, Wales, UK
Claire Price (Swansea University, UK)
Swansea in June was the picturesque setting for the British
Yeast Group (BYG) meeting 2016. The three day conference
was organised by Professor Steven Kelly, Professor Diane
Kelly, Dr Josie Parker, and Dr Claire Price, and hosted by
Swansea University Medical School on the beach-side
Singleton Campus.
Researchers from across the UK and Europe, together
with invited guests from the US, came together to discuss
a broad range of topics. Experimental approaches relating
Poster session during the BYG meeting
Delegates at the BYG meeting
46 December 2016 © Biochemical Society
to popular model eukaryotic microorganisms, such as
Saccharomyces cerevisiae, and medically important species,
such as Candida, were covered. The programme included a
rich variety of talks from invited speakers and those chosen
from submitted abstracts. On the first day of the meeting , the
poster session was a great mix of science and celebration, with
beer provided by Mumbles Brewery, a brewery from the local
Swansea area. The ERDF and Beacon+ sponsored meeting
dinner on day two was held at the centrally located National
Waterfront Museum and was preceded by the true highlight
of this meeting, the Carl Singer Foundation Session.
The Carl Singer Foundation Session is a great initiative
from Singer Instruments, and has been a fixture at BYG
meetings for the last few years. Specifically for students it
promotes humour through talks that last for six minutes (plus
two minutes for questions). This year saw some of the best
ever presentations, with the students, not only showcasing
excellent research, but also really embracing the nature of
the session, including doing the splits on the stage, singing
and even juggling! (Pictures of the event can be viewed by
searching for the conference hashtag: #BYG2016 on Twitter)
BYG meetings are a highlight in the calendar for any
yeast researcher. The very first meeting took place in 1977
and has been an annual event since 1980. The immediate
future of this institution looks strong with the meeting in
2017 being held in Canterbury and overseen by Professor
Mick Tuite.
■
News
Metalloproteinases and their inhibitors:
beginning, past and future
4–5 August 2016, Keble College, Oxford, UK
Linda Troeberg and Yoshifumi Itoh (University of Oxford, UK)
This conference was held at Keble College, Oxford to
celebrate the contribution of two leading figures in the
field of metalloproteinases, Professors Hideaki Nagase
(University of Oxford) and Professor Gillian Murphy
(University of Cambridge) upon their retirements and 70th
birthdays. The meeting was co-organized by Yoshifumi
Itoh (University of Oxford), Linda Troeberg (University of
Oxford) and Jelena Gavrilovic (University of East Anglia),
who have worked closely with Hideaki and Gill for many
years. 100 delegates attended the meeting, including 14
invited speakers, 33 principal investigators and more than
40 graduate students and post-doctoral researchers.
Metalloproteinases are a large group of proteolytic
enzymes that modify the microenvironment of cells
and play crucial roles in tissue remodeling. Talks and
posters covered a broad range of topics, reflecting the
important role metalloproteinases play in physiological
processes such as development and immunity and also in
pathophysiological settings such as cancer and arthritis.
Evaluation of the enzymes as potential therapeutic targets
or tools for diagnosis were highlighted by several speakers.
Keynote presentations by Professors Nagase and Murphy
stressed that understanding the fundamental biochemistry
of metalloproteinases is a prerequisite for reaching their
translational potential. An emerging theme was the role
of metalloproteinases in subtle modulation of protein
function. For example, Christopher Overall (University
of British Columbia) and William Parks (Cedars-Sinai
Medical Center) discussed how metalloproteinases
regulate immune responses by processing cytokines,
chemokines and matrix proteins.
Young scientists were well represented at the
meeting, with eight speakers selected from submitted
abstracts. Simone Scilabra (Technische Universität
München) won the oral presentation prize for his
talk on development of a ‘trap’ to increase levels of
the protective metalloproteinase inhibitor TIMP-3 in
tissue. Pernille Søgaard (University of Oxford) and
Kim Lemmens (Catholic University of Leuven) won
the poster presentation prizes, for their work on the
collagen receptor DDR1 and on axonal regeneration in
zebrafish, respectively.
Feedback from delegates has been overwhelmingly
positive, with attendees enjoying the opportunity to come
together and celebrate Professors Nagase and Murphy’s
contribution to our field. Students in particular benefited
from the strong line-up of world-leading international
speakers. The meeting provided the community with a
valuable opportunity to reflect on the history of this field
and to identify future research priorities.
■
Delegates at the conference
December 2016 © Biochemical Society 47
News
Society News
Thank you to Chair of the Executive
Committee, Steve Busby and Honorary
Meetings Secretary, Sheila Graham
David Baulcombe (President, Biochemical Society)
Steve Busby
Sheila Graham
As December marks the end of their terms, I would
like to take this opportunity to thank Steve Busby
and Sheila Graham for their work and commitment
in building and growing the Biochemical Society to
what it is today.
Steve has been Chair of the Executive Committee
since January 2014 and his stewardship of the
Biochemical Society has been characterized by his
continuous support for the core aim of the Society, to
advance the molecular and cellular biosciences and
the wider life sciences through our membership of
the Royal Society of Biology and the Charles Darwin
House Partnership, as well as through collaborative
activities with our sister Societies.
One of his first responsibilities as Chair of the
Executive Committee was to work with the previous
Chair, Colin Kleanthous, to lead the Society’s Strategy
Retreat in 2013, which resulted in formation of the
Society’s five-year strategy (2014–2018). Steve also
chaired the review of this strategy in 2015, where our
objectives were refocused in the light of organizational
achievements and environmental changes, resulting in
confirmation of our revised objectives for 2016–2018.
Included in our achievements under Steve’s
leadership have been the launch of the new brand for
the Society and Portland Press, the ratification of our
new governance structure by the membership at the
2016 AGM, the opening of Charles Darwin House
2, the development of the Society’s Industry Strategy
and the launch of three new Awards to be added to
the Society’s portfolio from 2018. These awards
will recognize Teaching Excellence, Industry and
Academic Collaboration, and International research.
Also stepping down is Sheila Graham. Sheila took
up the position of Honorary Meetings Secretary in
January 2012.
48 December 2016 © Biochemical Society
Over the past five years, Sheila has led the Meetings
Board to ensure that our conference programme has
covered a diverse range of subjects providing a platform
for knowledge-sharing, networking and collaboration.
She led the Board to agree on the restructuring of
the Theme Panels to reflect contemporary molecular
bioscience and, working closely with the Education,
Training and Public Engagement Committee, and in
particular its Chair, Rob Beynon, contributed to the
formation of the new Training Theme Panel that oversees
the Society’s programme of training events.
Under Sheila’s leadership tthe Society’s scientific
meetings covered topics ranging from basic science
to translational research in areas including protein
acylation, organelle crosstalk in membrane dynamics and
cell signalling, angiogenesis and vascular remodelling,
DNA damage response in physiology and disease and
chimeric antigen receptor therapy in haematology and
oncology. We have also seen a number of meetings run
in collaboration with other organizations including the
British Ecological Society, the Society for Experimental
Biology, The Protein Society, the British Society for
Immunology and the Royal Society of Chemistry,
reflecting the increasingly interdisciplinary nature of
molecular bioscience research.
Sheila has been a great ambassador for all of the
Society’s activities and in April 2016, she was co-host
of our first collaborative reception with the British
Pharmacological Society and The Physiological Society
at the Experimental Biology conference in San Diego.
It is my great pleasure on behalf of the members
of the Society and the Executive Committee to thank
you for your dedication and the great job you have
accomplished. We wish you all the very best in your
future endeavours and we look forward to your ongoing
involvement in the Biochemical Society.
■
News
Thanks and farewell to
John Lagnado
Freddie Theodoulou (Science Editor, The Biochemist)
In July we bid a fond farewell to John Lagnado who retired
from his position as Honorary Archivist after 16 years.
John also played an invaluable role as Book Reviews
Editor for The Biochemist and edited a “recent history” of
the Biochemical Society to mark the Centenary in 20111.
As Archivist, he oversaw the deposition of the Society
archives at the Wellcome Library, ensuring that this
valuable resource is now readily accessible and regularly
consulted. One of the most exciting developments during
John’s long tenure was the retrieval of Fred Sanger’s
laboratory notebooks from his attic, a story which has
been amusingly recounted in this magazine. We will miss
John’s great charm and erudite wit, and thank him very
John and Jenny Lagnado at the Society’s Summer Party
warmly for his longstanding and extensive contributions
to the Society.
■
Reference
1. Lagnado, J., ed. 2011 Biochemical Society Centenary:
The Last 25 Years. Portland Press.
UNDERSTANDING
BIOCHEMISTRY
Up to date overviews of key concepts in
biochemistry for 16-19 year olds.
FREE TO DOWNLOAD
bit.ly/understandingbiochem
December 2016 © Biochemical Society 49
News
CEO Viewpoint
Kate Baillie
(Chief Executive,
Biochemical Society
and Managing Director,
Portland Press)
One of the most important weeks of the science
calendar is the announcement of the Nobel Prizes. We
were very pleased to see that in 2016, the Nobel Prizes
brought autophagy and molecular machines into the
public consciousness. To celebrate this, we created a
collection of articles from across the Portland Press
portfolio, highlighting research in both fields (http://bit.
ly/2dbJQTQ). If you have an interest in autophagy, the
83rd Harden Conference, Autophagy: From Molecules
to Disease II, will be held in July 2017.
As their terms of office are coming to an end, I would
like to take this opportunity to thank Steve Busby, current
Chair of the Executive Committee, and Sheila Graham,
Honorary Meetings Secretary, for their outstanding
contribution to the Society. Some of the changes to our
Society committee structure, arising from the recent
Governance Review, take effect in the New Year and I’m
looking forward to working with David Baulcombe as he
takes on the additional responsibilities associated with
the reconstituted role of President, Anne Dell, Chair of
the new Executive Management Committee and Stefan
Roberts, our Honorary Meetings Secretary. If you would
like to know more about the Society’s governance, you
can find more information on our governance webpage
(http://bit.ly/2ef9UdO).
On 27 September, the Charles Darwin House (CDH)
Directors and Trustees of the co-owner societies met to
review the long term strategy for the Charles Darwin
House bioscience centre. A number of decisions were taken
which require ratification by the Trustees of the co-owning
societies, but they include proposals which will be of direct
benefit to Biochemical Society members including the
conversion of the Library Area on the ground floor into
a Members’ Area, which any individual member of any of
the societies can use as an informal space when they are
in London. Individual members of the co-owning societies
will also have the opportunity to book a limited number of
rooms in the conference centre at a nominal charge.
The co-owners also plan to manage two joint projects,
to enhance collaboration across CDH Societies, including
a photographic competition, the results of which will be
used to create an attractive display in the large window of
CDH 2 on Gray’s Inn Road and joint activities to celebrate
World Days in scientific areas of mutual interest.
The Local Ambassador Day was held on 17 November
at CDH. During the day, the Local Ambassadors were
updated on last year’s activities and discussed the future
direction of the Society. The meeting was followed by
the GlaxoSmithKline Award lecture, which this year was
given by Professor Charles Swanton on ‘Cancer Diversity
and Evolution’.
50 December 2016 © Biochemical Society
You may have read in previous issues, about
our strategic focus on engaging with the industrial
community. We are delighted to report that we are in the
second year of implementing our industry strategy and
early in October we launched a new page highlighting
ways that those of you working in industry can become
involved (http://bit.ly/2doUzZy). If you would like
more information please contact Laura Woodland our
Head of Membership Engagement at membership@
biochemistry.org.
As a member organization of the Royal Society of
Biology (RSB), on 20 September, I attended a Keynote
Speaker event on ‘Bioscience links across academia and
industry’ organized by the RSB. Dr Malcolm Skingle CBE,
Director of Academic Liaison, GSK and David Blanchard,
Chief R&D Officer, Unilever spoke about existing and
potential bioscience links across academia and business,
and the event also offered the opportunity to network and
discuss industry and employer engagement.
I am also pleased to report that following the UN
General Assembly, on 21 September, the Biochemical
Society along with the other members of the Learned
Society Partnership on Antimicrobial Resistance
(LeSPAR), released a statement welcoming the
recent news of global political and pharmaceutical
industry support for actions to tackle the threat of
resistant infections.
Reflecting on the importance of addressing this issue,
we organized a panel discussion at the New Scientist
Live event in partnership with the Microbiology Society
on living in a post-antibiotic era (see p.42), which was
attended by over 600 people. A second event focused
on antimicrobial resistance (AMR) was Policy Lates on
10 October organized by the RSB on behalf of the UK
members of the European Federation of Biotechnology
(EFB) where a panel of experts examined the roles
of innovation and regulation in tackling the AMR
crisis from different perspectives, including veterinary
research, biotechnology and public health (see p41).
This month, we will attend Pharmacology
2016 (http://bit.ly/2dgNyXg) where there will be a
Biochemical Society session on ‘Biochemical strategies
in drug discovery and targeting’, chaired by Patrick Eyers
and Yousef Mehellou. Pharmacology 2016, the British
Pharmacological Society’s flagship annual meeting, will
be held on 13–15 December 2016 at Queen Elizabeth II
Centre, London. Reduced registration rates are available
for Biochemical Society members and we hope to see
many of you there.
Wishing you all happy holidays, I am looking forward
to another successful year for the Society in 2017.
■
News
From the Chair
Steve Busby
(Chair of the
Executive Committee)
The arrival of the December issue heralds the end of the
year so, first, let me wish all members and readers, the
very best for the festivities associated with Christmas and
the New Year. This is the opportunity for some ‘down’
time, a change of pace, some indulgence, some festivities
and, maybe, some serious thought too. So, for all of us,
may these special days be filled with all of these things,
and not just used to catch up on writing papers, finishing
grant applications, and reading the Biochemical Journal!
Readers could be forgiven for thinking that the theme of
this issue, ‘Shine a Light’, is somehow linked to its timing.
I am told that this is just a coincidence, but, since light
is such a powerful symbol for Christmas and the New
Year, it’s a nice thought. Rather, the reason for the choice
of theme is the increasing use and usefulness of light to
our studies, whether of single molecules, single cells, or
imaging in whole organisms. So whether it’s the use of
super-resolution fluorescence microscopy to follow the
movement of single molecules in cells, or optogenetics to
trigger specific gene expression in specific cells, targeted
radiation now needs to be an essential part of every
molecular bioscientist’s toolbox.
At the end of this year, my term as Chair of the
Executive Committee of the Society finishes, and
Professor Anne Dell from Imperial College London will
be taking over the role, with the handover coinciding with
start of the Society’s new governance arrangements. It has
been thoroughly enjoyable and a real privilege to serve the
Society as vice-Chair and then Chair for successive 3 year
periods, but I do think that change, with new faces and new
ideas, is essential, and I am sure that the Society will thrive
with Anne as Chair, and Sir David Baulcombe as President.
A lot has happened over the past 6 years with major staff
reorganizations, changes in the way the Society operates,
closure of our Colchester office, the opening of a second
Charles Darwin House (CDH2) on Gray’s Inn Road, and
the setting and resetting of the Society’s objectives at two
Strategy Away Days. We now hope for a period of stability
and consolidation, as we move into 2017, but the Society
is always ready to take new initiatives to further its goals,
always ready to respond to changes in the sector, and,
in any case, future stability depends on income targets
being met. At the final meeting of the current Executive
Committee in October, I reiterated my conviction of
the ongoing need for a vibrant distinct Learned Society
focused on supporting Molecular Bioscience at all levels,
and my belief that our Society did this very well, especially
with support for bench scientists. I also underscored our
ongoing obligation to communicate our science to others,
notably the general public, but also to industry, policy
makers, educators and students. Again, the Society does
this very well, but it needs to be done in the context of
biology, with an eye to relevance to the wellbeing of the
planet and life on earth (not to mention the economy). My
view is that this is where our partnership with the other
CDH stakeholders is crucial, and, to my mind, this will be
a recurring theme as we move forward. So, in signing off
my final ‘From the Chair’ piece for The Biochemist, the
conclusion is that there is still lots to do, but the hard work
and professionalism of the Society’s staff, led by our CEO,
Kate Baillie, together with the dedication of the Trustees
and the enthusiasm of the Members will see us achieve
and go from strength to strength. So I want to thank all
the Staff and Trustees for making my job so easy to do, and
the team who conceive and manage The Biochemist, led by
Freddie Theodoulou and Niamh O’Connor respectively,
for producing the brilliant, stimulating and informative
product that you are reading on screen (or holding in your
hands, if you are a bit old-fashioned like me!).
■
People in white coats
By Benoît Leblanc
(http://peopleinwhitecoats.blogspot.co.uk)
December 2016 © Biochemical Society 51
Back reactions
Prize Crossword
N.A. Davies
1
2
4
3
5
7
6
9
8
10
11
12
13
14
15
16
17
18
19
Across
2. Instrument for visualising
small objects (10)
6. Lightwave amplification
by stimulated emission of
radiation (5)
8. To cause to pass through a
medium (8)
11. Taking up and storage of
energy (10)
14. Change in a quantity over
distance (8)
16. Pathway through a cell
membrane (7)
17. Absence of light (4)
18. Electromagnetic radiation
(5)
19. Apparatus for gathering
and concentrating light (9)
20. Of, or relating to space (7)
Down
1. Pigment found in rod cells
(9)
3. Biological processes with a
24 hour cycle (9)
4. To go back in time (4)
5. Larva of the European
beetle, Lampyris noctiluca
(8)
7. Material able to change the
direction of light (10)
9. 800nm to 1mm wavelengths
(8)
10. Enzyme that gives fireflies
their glow (10)
12. To issue forth suddenly (5)
13. Sudden emission of light (5)
15. Of or relating to time (8)
20
Solutions to the crossword featured in the October issue are: Across: 2.Oxygen, 4.Reduce, 8.Monoxide, 9.Function, 10.Gas, 11.Endocrine,
12.Hormone, 16.Message, 19.Nitric, 20.Radical, 21.Sulphur. Down: 1.Hydrogen, 3.Nitrous, 5.Cyanide, 6.Dioxide, 7.Biochemical, 13.Oxidise,
14.Paracrine, 15.Methane, 17.Sulphide, 18.Enzyme
Crossword Competition
Win
This month’s crossword prize is an Mpow® 3 in 1 Clip-On lens kit for smartphones.
Simply email the missing word, made up from letters in the highlighted boxes to
[email protected], by Tuesday 3rd January 2017.
Please include the words ‘December crossword competition’ in the email subject line.
Congratulations to the winner of the October competition:
The missing word from last issue’s competition was ETHYLENE
Emily Knight from Canterbury Christ Church University received an electronic weather station as the prize.
Terms and conditions: only one entry per person, entrant must be a current Biochemical Society member; closing date Tuesday 3 January 2017. The winner
will be drawn independently at random from the correct entries received. The winner will receive a Mpow® 3 in 1 Clip-On lens kit for smartphones. No cash
alternative available. No employee, agent, affiliate, officer or director of Portland Press Limited or the Biochemical Society is eligible to enter. The winner
will be notified by email within 7 days of the draw. The name of the winner will be announced in the next issue of The Biochemist. The promoter accepts no
responsibility for lost or delayed entries. Promoter: Biochemical Society, Charles Darwin House, 12 Roger Street, London WC1N 2JU; do not send entries to
this address.
52 December 2016 © Biochemical Society
Summer
Vacation
Studentships
Vacation lab placements
for undergraduate students.
Summer 2017
Grants are available for stipends of £200 per
week for 6 – 8 weeks, and up to £1,600 in
total, to support an undergraduate student to
carry out a summer lab placement.
This scheme not only benefits the student as
they get valuable research experience, but the
supervisor also gains an extra pair of hands in
the lab.
THE DEADLINE FOR APPLICATIONS IS 24TH FEBRUARY 2017
For full details on the criteria and more information on how to apply, please visit
www.biochemistry.org/Grants/EducationalGrants/SummerVacationStudentships
or contact [email protected]
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