Expert Advice on Stem Cells (for
Beginners)...
Thanks to
http://www.explorestemcells.co.uk/
Contents
Why are Stem Cells Important? ................. 3
Adult vs. Embryonic Stem Cells ................ 4
Stem Cell Controversy ............................... 5
Religion and Adult Stem Cell Research .... 7
Reprogramming Adult Stem Cells............. 9
How Alcohol Affects Stem Cells ............. 10
Building a Windpipe from Stem Cells ..... 12
Restoring Eyesight After Chemical Burns:
A Case Study ............................................ 14
Bone Marrow Stem Cells and Diabetes .. 16
Stem Cells to Treat Blindness ................. 18
Therapeutic Cloning ................................. 20
Bone Marrow Stem Cell Harvest ............. 22
Cancer and Stem Cells ............................. 24
Stem Cells for Stroke Victims .................. 25
Improving Memory With Stem Cells........ 27
Stem Cell Treatments for Joint Injuries .. 29
Stem Cells and Fat Distribution .............. 30
Restoration of Paralysis, can Stem Cells
Help?.......................................................... 32
Stem Cells to Revive Rare Animals......... 33
A Rare Side Effects of Stem Cell Therapy: A Case
Study ......................................................................... 35
Stem Cell and Cybrid Controversy ........................ 37
Why are Stem Cells Important?
To list the ways in which stem cells are important is a broad task
because stem cells use is virtually limitless. Stem cells have the
potential to treat an enormous range of diseases and conditions
that plague millions of people around the world. Their ability to
treat so many diseases rests on their unique properties of:



Self-renewal: stem cells can renew themselves almost
indefinitely. This is also known as proliferation.
Differentiation: stem cells have the special ability to
change into cells with specialised characteristics and
functions.
Unspecialised: stem cells themselves are largely
unspecialised cells which then give rise to specialised cells.
Human Development
One reason that stem cells are important is because we develop from stem cells. An understanding of
stem cells can teach us about early human development. Diseases such as cancer are thought to result
from abnormal cell proliferation and differentiation. This means that an understanding of where things go
'wrong' in stem cell division leading to cancer may help us find ways to prevent cancer or develop more
effective drug treatments.
Birth Defects
Stem cell research has the potential to teach us more about how birth defects occur and how these can
be prevented or possibly reversed. An understanding of the regulation and chemical triggers of stem cell
proliferation and differentiation are key to addressing birth defects.
Cell Therapies
Probably the most important use for stem cells is in cell therapies. A cell therapy is a treatment that
replaces dysfunctional or diseased tissues with stem cells.
At present, stem cells are already used in cell therapies for treatment of some cancer types but this use
is still only in small numbers of patients.
The number of organs available for transplant is scarce in comparison with those requiring one. Many
people suffer and others will die whilst awaiting a transplant. Stem cells may replace damaged cells and
tissues for those who require a transplant. Alzheimer's and Parkinson's diseases as well as those
diseases affecting the retina and heart may also be treated using stem cells in the future.
Clearly, stem cell use is exciting and holds great promise for treating and perhaps one day curing many
diseases. Their importance ranges from an understanding of the principles behind human development
to the cell based therapies addressing those aspects that go awry during development and lead to
disease.
Adult vs. Embryonic Stem Cells
Research has been ongoing now for years as scientists have tried to
determine whether stem cells from adult tissues have the same
capabilities and potential as embryonic stem cells. So: which source
holds the advantage?
Development Potential
Embryonic stem cells have a far greater differentiation potential than
adult stem cells simply because embryonic stem cells can develop
into almost every type of cell in the human body. Conversely, adult
stem cells may only develop into a limited number of cell types, so
their potential applications are not as great as embryonic stem cells..
At present, it would appear that embryonic stem cells have the edge
as they differentiate more readily than adult stem cells.
Is More Better?
In the case of stem cells, the answer is yes, assuming that more stem cells still means viable, high
quality ones. Embryonic stem cells are capable of almost unlimited division, or proliferation, when placed
in a culture whereas adult stem cells do not multiply so readily. Embryonic stem cells can also be grown
fairly easily in the laboratory whereas adult stem cells are difficult to grow after isolation from mature
adult tissues. Stem cell replacement therapies require large numbers of cells and the current difficulty in
growing large numbers of adult cells means that their use for therapy at present is limited.
Effect on Recipient's Immune System
Adult stem cells hold a distinct advantage in that a patient's own cells are identified, isolated, grown and
transplanted back into the patient. The recipient's immune system does not reject the cells because they
are compatible with that person's body. With embryonic stem cells, the potential for immune rejection
may require strong immune suppressing drugs to combat rejection of the new cells. The patient may be
at risk from infectious diseases.
A Question of Cell Youth
Adult stem cells are more likely to have abnormalities from DNA mutations. The 'youth' of embryonic
stem cells means that they are less likely to carry.
Ethics
Since adult stem cells are derived from adult tissues, with consent from the patient, there is little, if any,
ethical dilemma to adult stem cell therapies. Embryonic stem cells, on the other hand, have triggered
enormous debate due to the destruction of an embryo following cell extraction. Also, embryo destruction
has essentially become entangled in the abortion debate, creating a mass of controversy between
religious leaders, politicians and the public.
Stem Cell Controversy
Mention the word 'foetus' and heated controversy is likely to soon
follow. This is particularly the case in the field of embryonic stem cell
research.
Embryonic stem cells are derived from the foetus and research into
the therapeutic properties of these stem cells and have triggered
massive debate amongst politicians, religious groups, the general
public and lastly, a minority of scientists.
Good and Bad of the Stem Cell Debate
Opponents of embryonic stem cell research compare the destruction
of an embryo to an abortion. They believe that the embryo constitutes life because it has the potential to
fully develop into a human being. Those against embryonic stem cell use believe that is it immoral and
unethical to destroy one life to save another.
By using stem cells and discarding the embryo, it is thought that human life is ultimately de-valued by
this act and is paving a slippery slope for further scientific procedures that similarly de-value life. In
particular, many religious groups who are adamantly pro-life have condemned embryonic stem cell
research and all of its applications. Other arguments against embryonic stem cells cite the fact that adult
stem cells are the ones currently being used in therapies and thus, there is no need to even venture into
embryonic stem cell territory.
Those who support embryonic stem cell research believe that an embryo is not equivalent to human life
because it is inside the womb. Supporters also contend that the societal costs of many diseases and
conditions, both in monetary and suffering aspects, means that the ethical concerns regarding
embryonic stem cell usage are not sufficient to warrant discontinuation of this promising therapy.
Another argument for embryonic stem cell research is that the embryos are leftover from in-vitro
fertilisation and would otherwise be destroyed, so they should instead be put to greater use. Even further
down the line in development is the belief that those embryos from legal abortions, which have already
been destroyed, would be better used to advance human health rather than simply discarded.
Any Solutions to this Conundrum?
Fortunately, there are alternatives but they are far from perfect and they do still require further research
before they can be used with an acceptable level of success. Two new embryonic stem cell treatments
avoid the foetal destruction by either:

Deriving embryonic stem cells without destructing the foetus
 Obtaining embryonic stem cells without actually creating a foetus
In altered nuclear transfer (ANT), an embryo is not created. A derivative of somatic cell nuclear transfer
(SCNT), the nucleus of the somatic cell (any body cell other than an egg) is altered, or genetically
reprogrammed, prior to being transferred into the egg. The alteration consequence is that the somatic
cell DNA still produces stem cells but does not generate an embryo.
In blastomere extraction, an embryo is created but not destroyed. This procedure is performed on a twoday old embryo, following the division of the fertilised egg into eight blastomeres or cells. Previously, the
technique for harvesting embryonic stem cells used embryos at a later developmental stage, when the
embryo is made up of approximately 150 cells. When these cells were harvested, the embryo was
destroyed. Embryonic stem cells can instead be extracted from blastomeres, therefore preventing
embryo destruction and allowing use of stem cells for research and therapeutic treatment of disease.
The other alternative is to strictly use adult stem cells because these are derived from adult tissues. The
therapeutic potential is lower, however, because adult stem cells can't differentiate into as many different
types of cells as can embryonic stem cells. They are also more likely to have developed genetic
abnormalities over time and they don't tend to replicate as efficiently.
It is unlikely that a comprehensive solution will be found for the embryonic stem cell debate anytime
soon. In the meantime, both national and international policies along with collective public views will
likely guide the research and therapy efforts for embryonic stem cells. There is no doubt that stem cells
have great potential for treating disease but there unfortunately still remain doubts as to the ethical and
moral ramifications of pursuing this potential.
Religion and Adult Stem Cell Research
Stem cell research holds enormous potential for treating a broad
spectrum of diseases but before that potential can even begin to be
harnessed, there must be a clear pathway to obtaining the research
needed to make stem cell therapies a reality. Since the advent of stem
cell research, one barrier to furthering stem cell research has been
religion.
The destruction of an embryo that occurs when embryonic stem cells
are extracted has angered and upset many religious groups, who see
it as 'murder' or the destruction of human life. They do, however, tend
to support the use of adult stem cells. With adult stem cells, extraction
is from adult tissues and does not result in the destruction of an embryo. In this way, religious groups are
pushing for a greater focus and research on adult stem cells. However, their efforts are not without
opposition from scientists and researchers themselves, mostly due to the different properties of
embryonic and adult stem cells. The two stem cell types have numerous benefits and challenges.
The Use Of Embryonic Stem Cells In Science
Embryonic stem cells have some special properties that really set them apart from adult stem cells. It is
these specific properties that have resulted in a greater support from the scientific community. At the
same time, the very nature of embryonic stem cells in terms of how they are isolated for research has
caused controversy for religious groups, thus pitting embryonic stem cells and adult stem cells against
one another.
Embryonic stem cells are pluripotent cells, which means that they have a unique ability to differentiate
into any of hundreds of cell types in our bodies. Not only that, but embryonic stem cells can more easily
be grown in the laboratory in comparison with adult stem cells. In a sense, they are younger and fresher
cells that can more readily be coaxed to grow as needed for research and therapeutic value.
Religious Arguments Against Embryonic Stem Cell Use
It is generally cited in the scientific community that there is no substitute for embryonic stem cells and
that adult stem cells simply don't hold the same potential as embryonic stem cells. These scientists also
explain that the embryos were discarded ones that would serve a better purpose by being put to use to
improve the health and lives of people suffering from devastating diseases such as diabetes and heart
disease.
Religious groups such as Catholics strongly disagree and support the view that life begins at conception.
By this notion, any research on embryos is synonymous with murder. Some of the more liberal religious
groups take a somewhat relaxed approach to stem cell research and do support the use of embryonic
stem cells. Others may support the use of embryonic stem cells but only when used under very tight,
rigid parameters.
The Case For Adult Stem Cells
Despite the fact that there are arguments for the benefits of embryonic stem cells as well as arguments
against the use, virtually everyone can probably agree that in an ideal world, adult stem cells would be
equivalent to embryonic stem cells. In this way, researchers and scientists could obtain more funding
and forge ahead to use adult stem cells as they attempt to find treatments and cures to some of the
most debilitating diseases. Researchers could avoid the controversy and funding issues that occur due
to religion and political factors.
The reality is still controversial as well because religious groups argue that adult stem cells are just as
capable as embryonic stem cells. Recent years have shown increased funding from religious groups to
adult stem cell research, with the hopes that greater interest in the use of adult stem cells will prompt
reduced use of embryonic stem cells. While there has been a great deal of promising research into adult
stem cells, including recent studies that suggested adult stem cells can be reprogrammed into
embryonic-like cells, current knowledge still dictates that embryonic stem cells hold far more therapeutic
potential.
The debate over the use of embryonic stem cells does not appear to be fading anytime soon. As
religious groups continue to push for the use of adult stem cells instead of embryonic ones, it may very
well be that we find new potential and uses for adult stem cells. Until that time, however, embryonic stem
cells continue to be the most promising stem cells but the surrounding ethical controversy may ultimately
prevent the full harnessing of embryonic stem cell power.
Reprogramming Adult Stem Cells
One of the challenges of stem cells research has been to appease the
ethical and moral controversies surrounding the use of stem cells.
These specific concerns are usually related to embryonic and foetal
stem cells because the harvesting of such stem cells does with most
techniques, result in the destruction of an embryo. It is not, however, a
simple case of simply using adult stem cells because embryonic stem
cells have some notable advantages over adult stem cells.
Embryonic or Adult Stem Cells?
Despite the ethical controversies surrounding embryonic stem cell
use, they tend to replicate more rapidly and they also have the ability to differentiate into many more cell
types than adult stem cells. Furthermore, because these cells are ‘younger’ than adult stem cells, they
do not usually have the genetic abnormalities that adult stem cells can develop over time.
Reprogramming Adult Stem Cells Into Embryonic Stem Cells
Several studies have been published from research performed in Japan. In the studies, adult stem cells
were essentially ‘rewound’ and the differentiation process ran backwards, which caused the adult stem
cells to revert into an embryonic stem cell like state. The cells were virtually identical to true embryonic
stem cells as was the gene expression. The cells were also capable of becoming a fully functioning
organism, which is a true ‘test’ of embryonic stem cells. Previously, a study on mice had stated that it
produced embryonic stem cells from adult stem cells. However, while these cells could develop into all
tissue types, they could not produce a live animal, which indicated that the cells were really only partially
reprogrammed.In a more recent study, however, cells were fully reprogrammed. By turning on the
expression of four chemicals in the cells of an adult mouse, these cells were reprogrammed in reverse to
an embryonic like state. Ultimately, the cells could not be distinguished from true embryonic stem cells.
The greatest challenge will still be to produce these results in human cells. First, however, many other
challenges will need to be overcome in studies before success with human cells can become a reality.
Challenges
Unfortunately, the process itself is not without its challenges. It is a very inefficient process because only
a handful of cells out of thousands can thus far be successfully reprogrammed. In addition, these
reprogrammed cells can go on to develop abnormalities, which must be resolved before any treatments
with the cells can become a reality. Another issue is that the four factors – or chemicals – used in
studies on mice may not be the same factors that allow for reversion in human cells. A retrovirus was
originally used to introduce the genes of each factor into the cells but such retroviruses can also activate
genes that trigger tumour growth. All of these issues must be resolved before this particular process can
become feasible for use on humans.
Still, the possibility to obtain the benefits of embryonic stem cells while originally using adult stem cells is
exciting because it provides a way to appease the ethical concerns regarding the use of true embryonic
stem cells. Until then, the controversy will still remain but continued research can hopefully provide
treatments for disease that are acceptable to all members of the public.
How Alcohol Affects Stem Cells
Alcohol is known to cause many health problems but new research
shows it can affect stem cells too. In particular, a recent study
suggests alcohol harms stem cells in the developing brains of
teenagers.
The study looks at binge-drinking, where a great deal of alcohol is
consumed over a short period of time, generally with the intention to
become drunk. It is a problem particularly prevalent among teenagers
in Britain and a number of other countries such as the United States.
Examining the Brains of Monkeys
Researchers looked at the brains of adolescent monkeys to determine how alcohol affected stem cells.
They chose monkeys because human and monkey brains develop in similar ways, making monkeys a
more reliable choice for experimentation.
A Year of Alcohol
Four monkeys were given alcoholic drinks flavoured with citrus for a period of nearly one year. They
received the drinks for an hour a day over this time period to mimic the effects of binge-drinking. After
two months following the end of nearly a year, the animals were dissected to look at how their brains
compared to monkeys that hadn’t received any alcohol.
Study Criticisms
One criticism of the study that should be noted, however, is that the monkeys continued to receive
alcohol throughout this period. In reality, a person who is binge-drinking usually does not consume much
alcohol throughout the week.
Instead, they would have bouts of consuming a lot of alcohol in a short period of time. In teenagers, this
behaviour is common on weekends, where a teenager drinks excessively but then abstains during the
week.
Fewer Stem Cells
Researchers found that the monkeys who had been given alcohol over the year had fifty to ninety
percent fewer stem cells than the healthy monkeys who did not have any alcohol. The stem cells that
were significantly reduced were those in the hippocampus part of the brain.
This area of the brain plays a key role in many important functions such as memory and spatial skills.
Essentially, the alcohol ‘kills off’ these crucial stem cells in the brain.
What Does it Mean Over Time?
Long-term, researchers think these results suggest long-term effects from binge drinking in teenagers. It
may also be part of the reason why binge-drinking teenagers are more likely to develop alcohol
dependence when they grow up into adulthood.
Issues in Underage Drinking
Underage drinking is a huge problem in Britain and around the world. Many government-mandated
initiatives have worked to combat binge-drinking in youth but it remains a major public challenge.
There are already many known health consequences as well as an increased risk of alcoholism when a
person is an adult. But now, this new study gives us yet another strong reason to put greater effort into
reducing the incidence of underage drinking – especially binge-drinking.
Reducing Binge Drinking Around the World
This study may help us to provide young people with enhanced education around how alcohol affects
their brains, especially in relation to stem cells. With a growing body of evidence to suggest that alcohol
harms stem cells in addition to all the other known damage, it’s more important than ever to find ways to
reduce the incidence of binge drinking.
Building a Windpipe from Stem Cells
Stem cells have been touted as the treatment of the future for many
diseases but perhaps surprisingly, they have also made the news
recently for their ability to rebuild areas of the body that have suffered
from tissue destruction.
These types of procedures have previously been difficult and
unsuccessful ones, partly due to immunological rejection of tissue
transplanted from someone else as well as the mechanics of
mimicking function and form for real human tissue.
Creating a Windpipe
For one patient, this treatment was not only a reality but also a livesaving one. Her trachea – or windpipe – was essentially 'rebuilt' using
her own stem cells. The newly built trachea then gave her an airway that functioned properly, which
ultimately saved the patient's life.
Functioning Windpipe
The airway had all the mechanical properties that are necessary to ensure the woman was able to
breathe properly. In fact, when doctors did testing on her lung functioning a couple of months after the
transplant, she performed at the high end of the normal result for a woman of her age.
Disease and Tissue Destruction
The woman had previously suffered from tuberculosis, which left her in the hospital as she struggled
with breathing difficulties. At the young age of thirty, she had two children and couldn't adequately care
for them or function on a day-to-day basis. Other methods of trying to rebuild or replace parts of the
airway haven't been successful and removing one of her lungs still carried an enormous risk of
complications.
Responding to Urgent Need
Since her case was a very urgent one and the research team involved had experienced success in
laboratory work with tissue transplantation, they decided to create a new airway using the woman's own
stem cells.
The team started out with a piece of trachea from a donor who had just died and then they performed a
procedure over the next month and a half to remove all traces of donor cells. The woman who was set to
receive the rebuilt trachea had bone marrow stem cells from her body extracted and grown in the
laboratory before the trachea was finished with her own cells and then transplanted into her body.
The results were positive and exciting for everyone involved, not only because the procedure restored
the woman's airway functioning but also because it signalled renewed hope for others who suffer from
tissue destruction due to injury or disease. The woman's ability to perform daily tasks when she
previously was challenged as well as her ability to now mother her children without restriction has been
a positive outcome for everyone.
Advancing Stem Cell Research
This accomplishment is particularly exciting for researchers because it shows that stem cells can
effectively rebuild damaged tissue in the body. The risk of immunological rejection is dealt with because
the adult stem cells are taken from the recipient's own body.
There is also no need for the recipient to take special immune-compromising drugs to reduce the risk of
rejection, which further increases the success and health of the recipient transplantation. Hopefully, we
will see more success in tissue transplantation for future disease sufferers.
Restoring Eyesight After Chemical Burns: A Case
Study
Millions of people suffer from damage to their cornea – all occurring
from a wide range of injuries that can leave a person with irreversible
damage to their eyesight. Corneal issues and injuries are a top cause
of visits to eye care clinicians. As expected, losing eyesight is a
devastating experience for those who suffer from corneal damage.
Accessing Corneal Treatment
In fact, those who are fortunate may qualify for a cornea transplant but
in an ideal world, a solution would involve restoring a person’s
eyesight naturally. Even more ideal would be if everyone could access
such a treatment, without having to wait for invasive surgery that does not guarantee successful
restoration of eyesight.
Repairing the Cornea Using Stem Cells
In a recent study, scientists showed positive results when they tried to restore eyesight after corneal
damage had occurred to a patient. The treatment uses the patient’s own stem cells, reducing the
concerns about immunological rejection.
By using the patient’s limbal stem cells, which are found at the corneal edge and are unscathed,
researchers were able to coax the cells to grow new tissue. This tissue was then grafted into the eyes of
the patient. Ten years later, the procedure was still successful.
How is it Different from a Corneal Transplant?
In a corneal transplant, the damaged or diseased part of the cornea – known as the button – is removed
and replaced with the donor’s button. As with many transplant procedures, the donor’s body has to
match the patient’s or the patient is likely to suffer from immunological rejection. This means their body
senses the foreign tissue and attacks it, treating it as an invader.
The new stem cell procedure removes this issue and allows for a patient’s own stem cells to be used,
rather than spend time and effort looking for a donor. It opens the door to faster treatment that has a
greater chance of success.
Who Benefits from the Stem Cell Treatment?
There are many reasons people can suffer from corneal damage. Researchers particularly want to help
those who work in fields where there is a high risk of corneal damage.
This includes people who provide relief for oil spills and are exposed to chemicals that can burn the
eyes. Thousands of people suffer from chemical eye burn injuries at work each year and this treatment
could save their eyesight.
Other people who may benefit are those who suffer from side-effects that target the eye, such as
inflammatory diseases, including lupus and shingles. Once the stem cells regenerate this outer layer of
the cornea where damage often occurs, eyesight can be restored.
Eyesight Restored After Stem Cell Treatment
One of the exciting aspects of this research is that a man who had been blind for fifty years had his
eyesight restored one year later. While corneal damage implies a need to provide treatment soon after
the damage, in reality the treatment can help people after they have suffered from decades of blindness.
Bone Marrow Stem Cells and Diabetes
The prevalence of diabetes has been growing and the goal of finding
a cure or more effective treatment than current options has become
increasingly important. Ongoing research since the turn of the century
has shown that when diabetic mice are injected with bone marrow
stem cells the stem cells were able to restore function to damaged
tissues. The findings are exciting for both researchers and those who
suffer from diabetes. It is hoped that continuing trials and research will
eventually bring effective treatments to the public.
What is Diabetes?
Diabetes refers to a condition whereby the body can’t produce the
hormone insulin or the body’s cells are resistant to its effects. For type
1 diabetics, their pancreas doesn’t produce the insulin required to
keep blood sugar within its preferred, finely tuned range. In type 2 diabetes, insulin production generally
occurs, albeit abnormally – but the body’s cells can’t properly use the hormone to regulate blood sugar.
Diabetics may be insulin dependent, where they require daily doses of insulin to balance out their food
consumption, or they may be able to manage their condition with diet and exercise. The complications of
diabetes are, however, enormous. Diabetes has a high morbidity, with complications ranging from
circulatory problems, nerve problems and heart disease to blindness. In addition, the daily challenge of
monitoring lifestyle and taking insulin when required can be mentally and physically exhausting for many
diabetics.
Benefits of Stem Cells for Diabetes
Studies in both Canada and the United States found that when stem cells were injected into the
bloodstream of diabetic mice, the stem cells found their way to the damaged pancreas, where they were
able to prompt the growth of new cells. It’s thought that something in the bone marrow somehow
activates the regeneration of cells. In one study, the symptoms of diabetes were reversed within two
weeks of the mice receiving bone marrow stem cell injections. Their high blood sugar levels were
reduced to almost normal values and their insulin levels were raised. Even more interesting was that the
cell growth wasn’t from the injected cells themselves. Rather, the injected stem cells triggered the
production of cells in the recipient’s own pancreas. The results were particularly fascinating to
researchers also because when stem cells were injected in healthy, non diabetic mice, there was no
change.
It’s almost as though the stem cells were ‘intelligent,’ in that they sought out the damaged tissue and
triggered the new cell growth. Another benefit of using bone marrow stem cells is that they can be
harvested from the patient’s own bone marrow, cultivated in the lab environment and then injected back
into the patient, where they can travel to the damaged pancreas and stimulate healthy cell growth. This
helps to avoid the problems associated with immunological rejection, where the recipient’s body
recognizes the injected cells as foreign and launches an attack.
Research Complications
Because it literally takes decades of research and trials before a new drug is introduced to the public, it
will be some time before this treatment would be available for diabetics, assuming that human trails are
successful. Given both the short and long term complications of diabetes, however, the research still
provides hope that we may one day find a cure for diabetes.
Stem Cells to Treat Blindness
For people who are blind, the thought of a treatment to restore their
sight may seem like an impossible dream. But it may eventually
become a reality after scientists last year were able to restore the
eyesight of a blind person. The treatment works by replacing those
cells in the eye know as retinal cells that have been damaged or worn
out from diseases such as macular degeneration. For the elderly in
particular, macular degeneration is a common concern as it can lead
to enormous loss of vision in one or both eyes.
What is Macular Degeneration?
Macular degeneration is a top cause of vision loss in older adults. This
is the most common illness that results in blindness in the elderly or
for those people who lose their eyesight due to diabetes. It wrecks
havoc on a person's central vision. This kind of vision is important for helping us to see objects clearly as
well as helping us to perform basic, everyday tasks such as reading a book or driving a car.
When macular degeneration strikes, it affects the area of the eye that is important for allowing us to see
fine details. The disease may progress very slowly so that a person barely notices any changes at all.
Or, it might progress rapidly, causing significant vision loss.
Stem Cell Therapies
Those who might benefit the most from this stem cell treatment are people who suffer from macular
degeneration. But researchers think it could work for other kinds of vision loss as well.
How it Works
To perform the stem cell transplant, researchers initially tested things out in blind mice. They injected
stem cells into the rear of the eye. The stem cells were able to replace the damaged photoreceptors,
which are small, important cells found in the retina. These photoreceptors are vital to your ability to see
things and they are very sensitive to light.
Interestingly enough, previous studies using stem cells had failed to restore sight. One reason for the
problem relates to the choice of stem cells. In the most recent study, researchers used stem cells that
were more mature than the ones previous researchers had used. The choice proved successful as the
stem cells developed into photoreceptors and were able to join with the nerves that lead to the brain.
Researchers hope to see these kinds of transplants happening on a greater scale in approximately ten
years. With many patients suffering from diseases in the eye that cause photoreceptors to die, this
research offers a way to provide photoreceptor transplantation, helping to restore eyesight for many
people around the world. The use of a patient's own cells also avoids the potential for immunological
rejection, a threat that comes with other types of treatment.
Cautiously Optimistic
Experts do still tend to warn that we should not assume this study means we automatically have a cure
for blindness. It is just one case study and there are still a number of challenges and risks that come with
the treatment. But it does offer hope for people who are blind from macular degeneration that they may
one day have their eyesight again.
Therapeutic Cloning
When people think of the word 'cloning' they are often hit with
frightening images of duplicate human beings being created in
somewhat of a mad scientist style experiment. In fact, many members
of the public were outraged when Dolly the sheep resulted from a
cloning experiment in Scotland. Therapeutic cloning, however, is
entirely different and does not involve the creation of a perfectly
copied human being. It is reproductive cloning that results in a copy of
a specific human being. In therapeutic cloning, no sperm fertilisation is
involved nor is there implantation into the uterus to create a child.
How is Therapeutic Cloning Performed?
Therapeutic cloning is another phrase for a procedure known as
somatic cell nuclear transfer (SCNT). In this procedure, a researcher
extracts the nucleus from an egg. The nucleus holds the genetic material for a human or laboratory
animal. Scientists then take a somatic cell, which is any body cell other than an egg or sperm, and also
extract the nucleus from this cell. In practical human applications, the somatic cell would be taken from a
patient who requires a stem cell transplant to treat a health condition or disease.
The nucleus that is extracted from the somatic cell in the patient is then inserted into the egg, which had
its nucleus previously removed. In a very basic sense, it's a procedure of substitution. The egg now
contains the patient's genetic material, or instructions. It is stimulated to divide and shortly thereafter
forms a cluster of cells known as a blastocyst. This blastocyst has both an outer and inner layer of cells
and it is the inner layer, called the inner cell mass that is rich in stem cells. The cells in the inner cell
mass are isolated and then utilised to create embryonic stem cell lines, which are infused into the patient
where they are ideally integrated into the tissues, imparting structure and function as needed.
Benefits of Therapeutic Cloning
A major benefit of therapeutic cloning is that the cells removed are pluripotent. Pluripotent cells can give
rise to all cells in the body with the exception of the embryo. This means that pluripotent cells can
potentially treat diseases in any body organ or tissue by replacing damaged and dysfunctional cells.
Another distinct advantage to this type of therapy is that the risk of immunological rejection is alleviated
because the patient's own genetic material is used. If a cell line were created with cells from another
individual, the patient's body would be more likely to recognise the foreign proteins and then wage an
attack on the transplanted cells. The ultimate consequence would be a rejected stem cell transplant.
This is one of the major challenges of organ transplants, alongside the fact that there is a huge shortage
of available organs for those who require the procedure. This means that therapeutic cloning has the
potential to dramatically reduce the wait times for organ transplants as well as the immunological
concerns associated with organ transplant therapy.
Therapeutic cloning is also important to enhancing our understanding of stem cells and how they and
other cells develop. This understanding can hopefully lead to new treatments or cures for some of the
common diseases affecting people today. In addition, the procedure would allow for scientists to create
stem cell therapies that are patient specific and perfectly matched for the patient's medical condition.
Problems with Therapeutic Cloning
One problem with therapeutic cloning is that many attempts are often required to create a viable egg.
The stability of the egg with the infused somatic nucleus is poor and it can require hundreds of attempts
before success is attained.
Therapeutic cloning does result in the destruction of an embryo after stem cells are extracted and this
destruction has stirred controversy over the morality of the procedure. Some argue that the pros
outweigh the cons with regards to treating disease whilst others have likened the destruction to an
abortion. Still others state that this doesn't change the fact the embryo could potentially be a human
being and so destruction of the embryo is no different than destruction of a human life.
Because reproductive cloning does utilise SCNT as the primary step, there is also still fear that given our
knowledge base to perform reproductive cloning, a scientist may attempt to move beyond therapeutic
cloning to creation of a human being.
To this date, no human being has been successfully cloned but the possibility of this occurring is a
frightening one not only for the general public and policy makers, but also for most of the ethical
scientific field. The majority of scientists are adamantly opposed to reproductive cloning and instead,
support therapeutic cloning for treating disease. With policies and careful monitoring in place to ensure
that therapeutic cloning is used responsibly, we can all benefit from the potential of this procedure to
eventually treat, or perhaps one day cure, many diseases.
Bone Marrow Stem Cell Harvest
A bone marrow stem cell transplant uses stem cells derived from bone
marrow to provide a fresh and healthy source of new blood cells which
in turn, allows for a patient to receive higher doses of chemotherapy to
treat certain types of cancer such as leukaemia. This ultimately means
that a person has a better chance of surviving cancer. The bone
marrow stem cells may be allogeneic and therefore donated by a
family member of stranger, or they may be autologous, which utilizes
a patient's own stem cells.
Importance of Bone Marrow
Bone marrow is the soft tissue found in the centre of bones. It is here
that new blood cells are formed; stem cells are considered the parent cells of these blood cells. Stem
cells in the marrow have the vital task of creating a person's three blood cell types. These are:
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Red blood cells: transport oxygen
White blood cells: fight disease
Platelets: aid in clotting after injury
Bone marrow stem cells are found in bone marrow and in a person's blood. After stem cells multiply,
they form immature blood cells, which are then subject to a collection of changes that allow them to
develop into mature blood cells. Once mature, the blood cells migrate from the marrow and are
introduced into the bloodstream, where they provide important functions in keeping the body alive and
healthy.
Effects Of Chemotherapy On Bone Marrow
Because chemotherapy operates by destroying the fast growing cancer cells, higher levels are generally
more effective for killing cancer cells. Similar to cancer cells, however, bone marrow cells grow quickly
and are also very sensitive to chemotherapy treatment. The chemotherapy can eventually destroy the
marrow completely, which then prevents new and healthy blood cells from developing.
Autologous Bone Marrow Stem Cell Harvest
In an autologous transplant, a patient's own stem cells are used. The problem here is that the patient’s
bone marrow and peripheral blood usually have a lot of cancer cells, so isolating stem cells can't
generally occur until the patient is in remission.
A patient will usually receive some chemotherapy to reduce cancer cells before stem cells are collected.
The harvested stem cells are also treated to ensure that no cancer cells remain. Higher doses of
chemotherapy are then given, sometimes alongside complete body radiation, to confirm that no cancer
remains. Stem cells are then transplanted back into the body via a rapid injection. Stem cells will
eventually migrate to the bone marrow, where they latch onto other cells there and develop into the
different blood cells.
Allogeneic Bone Marrow Stem Cell Harvest
In the allogeneic transplant, a suitable donor is used; this may be a family member or a person unrelated
to the patient. Similar to the autologous bone marrow stem cell harvest, a patient receives high doses of
chemotherapy and possibly also radiation therapy. This therapy will destroy the patient's marrow and
immune system, so that the patient's immune system can't attack the transplanted cells that are received
from the donor. Graft rejection is a very real concern for allogeneic transplants, where the recipient's
immune system recognizes the transplanted cells as 'foreign' and launches an immune attack. Prior to
the transplant, red blood cells in the stem cell sample are usually identified and discarded and
particularly so if the donor's blood group is different from that of the patient.
Stem cells are then infused into the patient via an intravenous line over several hours. Stem cells travel
to the patient's bone marrow where they develop and produce the blood cells necessary for blood
functioning. Patients may also still be given drug therapy for some time to reduce the chances of
immune rejection.
Bone marrow stem cell harvests are clearly a life saving technique for those suffering from certain
cancers such as leukaemia. They are one of the 'older' stem cell therapies and have been proven
effective for decades now. There are, however, still issues of rejection that warrant further development
and refinement of stem cell harvesting techniques. It is hoped that scientists will continue to focus on
research to improve the odds of success for this important treatment.
Cancer and Stem Cells
Cancer afflicts millions around the world each year and many go
through treatment only to relapse years later. Others die from the
disease and often after a great deal of suffering. It's no surprise that
cancer research is at the forefront for current medical studies. In
particular stem cells are being used for cancer treatments today as
well as driving current research efforts in the hopes of finding more
effective cancer treatments, including the ultimate goal of a cure.
Current Stem Cell Treatments for Cancer
Adult stem cells have been used for decades to treat certain cancers
through bone marrow transplants. In this therapy, the stem cells that give rise to the different blood cells
in the body are transplanted into the bone marrow of the patient, where they regenerate the blood. This
is a vital and often life saving treatment because chemotherapy destroys the bone marrow alongside
cancer cells and the blood cells must be replenished for the patient's treatment to be successful. It is
hoped that similar treatments for other forms of cancer, allowing for cancerous tissues in areas such as
the brain to receive stem cells that replenish those that are damaged through radiation.
Cancer Cell Biology
Treating cancer directly is one aim of stem cell therapy, but understanding cancer biology is another
important one. In fact, it's crucial because that understanding can then encourage the development of
drugs and cancer treatments. Some of the more recent studies have shown that cancers seem to be
regularly maintained by a relatively small cluster of cancer stem cells that are able to self-renew.
Scientists are trying to learn more about the genes that regulate the self-renewal feature of stem cells so
that drugs can be developed to destroy the cancer stem cells.
Stem Cells and Tumours
Another important focus involves identifying and isolating cancer stem cells from tumours so that
researchers can look at how cancer genes are expressed. The connection between cancer stem cells
and healthy ones is also being investigated in research studies.
Stem Cell Development and Cancer
Even when cancers develop in different tissues, they can still have similar genetic abnormalities. An
important scientific focus is to identify all of these genetic abnormalities and develop treatments to
combat the effects. By examining the developmental process of healthy stem cells, scientists can better
understand how abnormal differentiation occurs and develop treatments to prevent or treat the
abnormalities. An understanding of how stem cell differentiation and specialisation are controlled is
another fundamental development process that will help researchers create effective cancer treatments.
Because cancer rates have significantly increased over the last century and the incidence is such that
even if you do not suffer from cancer in your lifetime, you will likely know someone who does, stem cell
research must continue in this area. The chance to save lives and decrease suffering is exactly the sort
of motivation that should support further stem cell studies for cancer treatments.
Stem Cells for Stroke Victims
Brain damage that results from stroke is an enormous challenge to
address for people around the world. That's why research into stem
cell therapies for stroke victims is so vital to reduce the devastating
effects of stroke on its victims.
Stem Cell Study
A new study is set to go ahead in the United Kingdom (UK) to find out
if stem cells are able to repair brain damage suffered by stroke
victims. The company is aiming to begin clinical trials in the first half of
this year on twelve patients. While there has been some preliminary
success on stem cell treatments for similar brain damage, this new
study will address a condition that has widespread effects.
Designing the Study
In this British study, stroke victims will have neural stem cells injected into their skull. While it sounds
quite graphic, the injections will involve a very fine syringe and will target the parts of their brains that
have been more severely affected by the stroke.
Researchers hope that these neural stem cells will then develop into healthy brain tissue as well as
neurons and other related, supportive structures in the brain. If the study proves successful, it will mean
that the stroke victim's brain will have newly restored connections – a better, healthier brain network, so
to speak.
Taking Animal Studies to Humans
So far, we have also seen positive results from studies in mice, where they were able to regain brain
functioning following injury to the brain. These kinds of animal experiments have prompted the need for
human studies and it is hoped that this new clinical trial will provide similar – or greater – success.
One interesting aspect of this kind of study is that once the stem cells are injected, we don't know
exactly how they work and develop in the brain. We can measure the outcomes of the procedure but we
can't actually track everything that happens once the neural cells are injected. So, we don't know where
they travel exactly or how they change and develop.
Scans taken regularly can show brain functioning and activities after the treatment but the precise
process by which the brain 'heals' is something that for now, will remain a mystery. At best, we can hope
for a positive result by whatever physical mechanism occurs and perhaps in the future, we will also be
able to observe the pathway itself by which stem cells help stroke victims.
Awaiting Study Results
Many of us will be anxiously awaiting the results of the study, which provides hope for the many people
who have suffered from brain damage due to a stroke. For now, however, the best thing the rest of us
can do is to focus on preventative strategies to reduce the likelihood of suffering from a stroke.
With stroke being as prevalent as it is, it's likely most of us will either suffer from a stroke at some point
in our lifetime or we will know someone who does suffer from one and possibly has brain damage to
some degree as a result. Hopefully, the new British study will offer hope for everyone who is affected by
stroke or will be one day.
Improving Memory With Stem Cells
For people who suffer from Alzheimer's disease, losing their memory
is devastating. While there is a great deal of active research into how
to treat the disease, we still don't know how to predict who will be
diagnosed with Alzheimer's disease or how to effectively treat them.
As the leading cause of dementia in the elderly, finding better ways to
reduce the memory loss from Alzheimer's disease is a priority for
researchers.
Benefits of Neural Stem Cells
A study using stem cells, however, suggests promise for potentially
improving the memory of people who suffer from Alzheimer's disease.
Researchers used mice to look at how stem cells could improve memory. They genetically engineered
the mice to have Alzheimer's disease and treated them with stem cells.
Neural stem cells were injected into the brain of each mouse. Results showed that the mice performed
much better on memory tests one month after receiving the stem cell injections. Researchers believe the
stem cells have a protein that improves neural connections, helping to enhance the cognitive
performance of the mouse. But just how did it work?
Regenerating the Brain
Researchers were actually surprised when they looked at the mouse brains. They had thought that the
neural stem cells might have become fresh, new neurons. Or they thought that perhaps the stem cells
had reduced the plaques that are classic signs of Alzheimer's disease. Neither was the case. In fact,
less than ten percent of the stem cells had become neurons.
Instead, the stem cells had secreted a special protein. This particular protein triggers the growth of new
neurites. These neurites grew from tissue that was already present in the brain. The result was that the
neurites enhanced the connections between the brain's neurons. To confirm the results, researchers
even reduced the protein from the neural stem cells and found that this benefit was removed.
Improvement That Lasts
Researchers also tried to just inject the mice with the protein, but although the mice showed some
improvement, they did not show nearly as much improvement as when they received the neural stem
cells. It seems that the injection of neural stem cells offers a longer lasting and more regular supply of
this important protein.
Understanding How it Works
Researchers are still trying to make sense of the new findings. It seems that the plaques that are seen in
patients who have Alzheimer's disease are not the key area to look at when it comes to dementia. It is
the loss of connections from one neuron to another in the human brain.
This makes sense with what we know about the stem cells once they were injected into the brain. These
neural stem cells acted like a helping hand to encourage the brain to create new synapses. The stem
cells also helped to repair those neurons that were damaged from disease.
Hope for Alzheimer's Disease
With the incidence of Alzheimer's disease continuing to rise, finding ways to reduce the damage remains
the key to overcoming the devastating effects. As stem cell research grows, we may one day find a way
to bring neural stem cell treatments to those who need it.
Stem Cell Treatments for Joint Injuries
Joint injuries can be extremely difficult injuries to treat particularly
because they are often slow healing, painful and have an enormous
effect on a person’s mobility. In addition, missing or damaged
cartilage can’t be replaced, which presents a complicated challenge
for recovery. Joint injuries generally affect people of all ages but
specifically, joint injuries can occur quite frequently in athletes or
others who place a large amount of stress on the joints. Aging and
similar factors can also compound the rate of healing, creating a
challenge for a patient to obtain normal functioning and movement
after the injury. The unfortunate end result can be a joint that remains
susceptible to injury and is also weakened from repeated injury. Stem
cells may, however, be able to eventually fill the gap, so to speak, and provide the missing tissue for
those who have suffered from joint injuries.
Using Animals
Recent research has used horses as a model because joint injuries for this animal are both common and
expensive. By using this model, they hope that the research can then be followed up through more
extensive studies on humans. Researchers have used the horses’ umbilical cord as a source of stem
cells, which is generally convenient and easy to obtain for this animal. It’s thought that since the stem
cells are so ‘young,’ they are less likely to be rejected by the recipient’s immune system. They are also
capable of greater divisions. Another benefit to using these stem cells is that their potential to
differentiate into a greater number of cell types is higher than the potential found in adult stem cells.
Furthermore, obtaining cord blood samples isn’t particularly invasive in comparison with obtaining
samples from other sources, such as bone marrow. Yet another benefit is that the majority of ethical
concerns regarding stem cells involve embryonic of foetal stem cells; thus, use of cord blood stem cells
helps to avoid some of these challenges.
Progress
Researchers have been working to differentiate the stem cells into several different cell types, which
include the main constituent of cartilage – chrondocytes. Their aim has been to isolate stem cells and
then coax them to differentiate into the specialized cells required to treat joint injuries. If cartilage tissues
could be cultured in the laboratory and then successfully implanted in the patient, the rate of healing
could be substantially improved. The formation of scar tissue that occurs following an injury can also
hinder the functioning and movement of the limb. Stem cells, however, may be able to provide help in
this area by reducing the formation of scar tissue and facilitating faster healing.
Despite cartilage attachment to bone being difficult to reproduce in addition to its complicated structure,
new research holds hope for those with joint injuries, particularly athletes and similar individuals who are
prone to these types of injuries. Treatments are still many years away from approval and a great deal of
research and development is still required. Current research does, however, still show once again the
enormous potential for stem cells to improve health.
Stem Cells and Fat Distribution
Being overweight carries a number of health risks, but where you
carry that extra weight can increase the risk even further. One
important area of research is to learn how and why some people are
more likely to gain weight around their midsection – known as visceral
fat. Stem cells have recently shown promise in helping us learn more
about body fat distribution.
Why is Visceral Fat Dangerous?
Visceral fat is thought to result in a significantly higher risk of
cardiovascular disease and diabetes compared to subcutaneous fat –
the type of fat that is found under the skin. It is why those with a ‘pot
belly’ are generally more likely to suffer from these two diseases.
Challenges of Losing Visceral Fat
Unfortunately, visceral fat is also difficult to shed and some people find it is the last place where they
shift fat during their weight-loss process. Some studies suggest that exercise is particularly important for
shedding visceral fat. It would be ideal, however, to learn more about how it is gained in the first place so
that preventative approaches could be used.
Stem Cell Development
Some stem cells will develop into adipose cells, which are the large cells that store and process fat we
take in from food. Whether nutrition can influence which stem cells become visceral or subcutaneous
ones is an important question. Do certain kinds of fats in the diet play a part in visceral gains?
The answer is an important one and could then help us prevent and treat obesity. Scientists wanted to
see what would happen if commonly consumed kinds of fat were added to the cells, which could end up
suggesting that nutrition plays a role in body fat distribution.
Adding Palmitate to Stem Cells
In this recent study, scientists added fat to mouse stem cells and found that it influenced their response
to specific signals that turn the cells into either visceral fat or subcutaneous fat. If palmitate, which is a
part of palm oil, was added to the stem cells, it affected their response to sex hormones. These sex
hormones are ones that control the type of fat cells a stem cell will eventually become. Researchers
concluded that the kind of nutrition available to the cells seems to affect the distribution of fat cells. This
result adds to evidence that suggests a person’s genetics also play a role in body fat distribution.
Rising Levels of Obesity
In the UK and other westernised nations, obesity is continuing to rise, bringing an enormous health
burden to the public and healthcare systems. Diseases such as type 2 diabetes traditionally occurred in
much older adults but it is now more prevalent in younger adults and even adolescents.
Reducing Obesity Using Stem Cells
With approximately thirty percent of young people in the UK being overweight or obese, it is vital that we
find ways to identify the factors underpinning obesity. This is especially true in terms of visceral fat. It is
thought that this recent study can help us eventually find new treatments that target visceral weight
gains in those most prone.
Restoration of Paralysis, can Stem Cells Help?
Facial Paralysis
To rehabilitate a person with facial paralysis is an immense challenge.
To date, there is no 'perfect' treatment that allows for fully restored
functioning of the facial muscles and nerves. Not only that, but each
case is unique and has its own cause and issues for recovery. Also, the
level of paralysis and the area of the face where paralysis occurs will
similarly be unique for each patient. You can see how difficult it is to
develop the ideal treatment that will work for everyone!
Some patients will suffer from a lack of movement in the face while others can actually experience
excessive amounts. In this way, treating facial paralysis can be a multi-faceted approach. Your concern
and interest in your friend's treatment is a wonderful thing that is shared by many researchers who are
looking for ways to use stem cells to treat facial paralysis and its related consequences.
Using Stem Cells
There have been a number of studies that suggest stem cells have the potential to treat various kinds of
paralysis. However, most studies have focused on nerve damage. One recent study on rats found that
stem cells were able to bring back function and sensitivity. Studies on humans would be needed to
confirm the findings and open the door to the treatment becoming a reality.
Another study found that stem cells were able to seek out injured muscle and essentially 'regenerate' the
muscles. Stem cells that were injected into a person with injured muscles showed that the stem cells
clustered in the area of injury and rapidly gave rise to healthy, functioning muscle cells.
Importance Of Safety
One key reason that a stem cell therapy for paralysis is not yet routinely used is that more testing needs
to be done to assess the safety of the treatment. There is still a great deal we do not know about stem
cells and the unpredictability factor is such that we need to see more successful experimental cases of
stem cell therapy in paralysis victims.
It is expected that stem cells may eventually be a routine treatment for facial paralysis – as well as other
kinds of paralysis.
Stem Cells to Revive Rare Animals
When we think of extinct animals, probably the first one that comes to
mind is a dinosaur. But most of us are likely happy to think of these
enormous creatures being exactly where they will remain – in the
past.
Yet other animals have sadly become extinct and the rate at which
species are lost is an alarming one, often due to human actions as
well. One approach for scientists has been to look at the potential of
stem cells to revive rare animals and increase the diversity of our
animal kingdom. But just how can this be accomplished exactly and
what are their challenges?
How the Process Works
To simply summarise how it works, the process involves using frozen material from a dead animal and
then reprogramming this material to become sperm and eggs. After, the theoretical outcome is that an
extinct animal could be ‘brought back’ to life.
Collaboration to Revive Rare Animals
A zoo in San Diego and the Scripps Research Institute are currently working together to discuss the
potential to revive rare animals. In fact, there was a yearly international meeting on stem cell research,
where scientists from the Scripps Research Institute talked about current experiments.
In these experiments, researchers had created stem cells from the frozen skin cells of a dead male drill.
This animal is a type of endangered monkey found in parts of the world such as Nigeria. The stem cells
that scientists had created are known as pluripotent stem cells, which were induced from the skin cells.
Challenges of Creating Stem Cells
To actually create these induced pluripotent stem cells, researchers had to use special viruses. These
viruses had been engineered to transport four human genes. The human genes are ones that are known
to be able to reprogram an adult cell into an embryonic stem cell format.
Unfortunately, this approach did not work when the researchers tried it with the northern white
rhinoceros. Feedback within the team indicated that the next step might be to use rhinoceros versions of
these particular genes that are normally used in the procedure.
Another issue involved in the goals of reviving rare animals is that when scientists reprogram genes,
there is also the chance that the induced pluripotent stem cells could become cancerous ones. The good
news is that other research teams have been hard at work to create techniques that make induced
pluripotent stem cells without leaving gene copies behind.
Creating Sperm and Eggs from Dead Animals
The ultimate goal with these experiments is to eventually trigger the induced pluripotent stem cells into
sperm and eggs. The zoo in San Diego has retained animal tissues as part of a special and unique
project. The zoo currently has more than eight thousand samples from more than eight hundred different
species.
Bringing Animals Back to Life
Researchers would like to see some of these animals brought ‘back to life’ to add genetic diversity to
their captive breeding initiatives. It is an incredible challenge but would essentially be breeding animals
that are dead – a surprising and unusual concept for most people to take on board but an exciting one
all the same.
A Rare Side Effects of Stem Cell Therapy: A Case Study
There is no doubt that stem cell therapy holds enormous potential.
Unfortunately, this potential also brings with it side-effects, some
particularly severe. Such was the case during a therapy that used
human foetal stem cells.
The boy in the case suffered from a rare genetic disease known as
Ataxia Telangiectasia. This disorder affects many areas of the body
and can cause significant disability. The body does not coordinate
properly and those who suffer from the disease have a weak immune system as well as problems with
their respiratory system.
Unexpected Consequences of Stem Cell Therapy
After undergoing foetal stem cell therapy at a clinic, the boy developed abnormal growths in his brain
and spinal cord. The growths were found approximately four years after he had received the stem cell
therapy.
While there have been some cases reported where experimentation on rodents resulted in the growth of
tumours after stem cell injection, this hadn't been documented in humans after foetal stem cell therapy.
Researchers also knew that this risk in rodents could be reduced if the stem cells were differentiated
before they were injected. This means that the stem cells were coaxed into the desired body cell for the
therapy prior to injection.
Examining a Benign Tumour
But how did the researchers know that in this boy's case, the tumour was indeed from the stem cell
therapy? It was all understood after the spinal cord growth was operated on and removed from the boy.
Doctors found that it looked like a glioneuronal tumour, which is a benign kind of neural tumour. After
more examination, it was determined that this tumour couldn't have stemmed from the boy's own
tissues.
A Weakened Immune System
As they tried to understand what went wrong, they considered that the very weak immune system that is
commonly seen in Ataxia Telangiectasia could have contributed to the growth. In a sense, the boy's
body was an ideal vessel to nourish the growth of this kind of tumour.
In a person who has a healthy immune system, the normal 'checks' on the body would be more likely to
prevent a tumour from establishing itself. We have known for some time now that there is the potential
for stem cells to trigger the growths of tumours but the reality has been that this is a rarity.
What it Means for Stem Cell Research
Although this rare side-effect of stem cell therapy may be used as part of a case against stem cell
research, this would not be a fair approach. Even the authors of the report state that their findings do not
imply that we should stop stem cell research.
Rather than put a stop to stem cell research, it has been suggested that we need to spend more time
looking at the safety of stem cells. We should try to find out more about what can potentially go wrong
and then develop safeguards to reduce any risks associated with stem cell therapies. This way, we can
get the most benefits from stem cells while minimising any chances of side-effects along the way.
Stem Cell and Cybrid Controversy
If you imagine the concept of something that is partly human and
partly comprised of another animal, then you will now be familiar with
one of the common misconceptions about cybrids and the subsequent
controversy around their creation and use.
Cybrids are the result of experiments that involve the fusion of human
DNA with animal eggs that have been 'emptied.' A cybrid is actually a
different type of embryo and differs from two other kinds known as
chimeras and hybrids. It is still considered fully human – not animal,
although it has been misrepresented through the use of grossly
exaggerated images showing a half man, half animal creature.
Usually, these images have been used to further a more extreme agenda against stem cell research. To
understand the concept of cybrids, however, you need to be familiar with the all of the different kinds of
experiments and the politics around each of them in Britain.
Creating A Cybrid
A chimera is an embryo that contains both human and animals cells while a hybrid is one that is created
when a human egg is fertilised by the sperm from an animal or an animal egg is fertilised by human
sperm. On the other hand, a cybrid is the fusion of DNA from a human with an animal egg that has
essentially been 'emptied.' With a cybrid, the embryo is created when a human cell nucleus is inserted
into an animal egg that has previously been emptied. These cybrids may soon even be exempt from a
ban on research that involves other human-animal embryos, such as chimeras and hybrids. It is thought
that cybrids can pave the way for improved knowledge and therapeutic treatment of conditions such as
Alzheimer's disease.
Controversy, Politics and Religion Around the use of Cybrids
With the ban on chimeras and hybrids, scientists have generally been the ones frustrated and angry
because the ban has compromised new ways to conduct stem cell research. This new cybrid approach,
however, may appease scientists but it leaves some members of the public and religious groups angry
at what they consider meddling with human life. With the use of cybrids, an empty egg from an animal
such as a cow would receive human DNA. Such human-animal embryos would actually be 99.9 percent
human and far from being qualified as a hybrid or chimera. The term cybrid comes from it being a
cytoplasmic hybrid and these cybrids would still be subject to stringent regulation despite being allowed
for use in research. In this way, cybrids would still be regulated and must be created and used within
specific parameters.
The lifting of a ban will help to relieve the frustration experienced by scientists and others in the research
sector that feel their work has been at a standstill with many of the laws around stem cell research. The
lifting of a ban would also result in less political and religious unrest than the lifting of bans on chimeras
or hybrids, primarily because a cybrid only has approximately 0.1 percent of its DNA being from an
animal. As such, a cybrid is for all purposes considered human. Still, there are those individuals who
oppose stem cell research in this capacity and are adamant that even cybrid research should remain
banned.
Future of the Cybrid Controversy
While the lifting of a ban on cybrid research may somewhat relax the challenges that scientists are
experiencing when conducting stem cell research, there are still those people who oppose any mixing of
animal and humans, even at such a miniscule level. The controversy is unlikely to die anytime soon but
it is thought to be less significant and widespread than any lifting of a ban on hybrid or chimera creation.
For now, most people can agree that we need to find treatments and cures to the devastating diseases
such as diabetes, but how we will find these therapies remains a controversial pathway.