Cell competition occurs when cells of different fitness levels confront one another
resulting in elimination of the weaker cells, while the stronger population survives and
proliferates. It has been proposed to act as a quality control mechanism to eliminate
suboptimal cells. Although several modulators of cell competition have been
identified, our knowledge of the mechanisms that enable fitter cells to trigger the
elimination of weaker cells is limited to very few players. Using a previously
established mammalian in vitro model of cell competition, we are investigating the
mechanisms involved in this phenomenon.
A collaboration was established with Matthieu Piel’s laboratory to further investigate
the spatial and temporal dynamics of cell competition and investigate a potential role
of differential adhesion.
The Piel lab recently developed a specialized co-culture system enabling cells to be
arranged in defined and reproducible patterns, using a combination of
micropatterning and ‘click’ chemistry to dynamically control cell adhesion. During this
visit I learnt how this system works first-hand and assessed its suitability for our
assays. I was able to successfully co-culture two different cell types in a number of
defined patterns, allowing us to control the exact distribution of each cell population
and the orientation with which the competing cells come into contact. We have used
time-lapse video microscopy to view competition between cell populations grown on
patterns. We have also used this method to establish competition assays on different
substrates to assess a potential role of differential adhesion. It is possible to coculture two different cell populations, each adhered on a different substrate. We are
now exploring if this can interfere with competition. To further investigate a role for
differential adhesion I used Reflection Interference Contrast Microscopy (RICM). This
microscopy technique determines the distance of a cell from its substrate, as the
intensity of the signal produced is a measure of proximity of the object to the glass
surface. Using this technique we observed that the two cell types differed in their
adhesion to a number of substrates.
This collaboration with the Piel lab has been a fantastic experience and we are still
benefiting from their expertise. I have learnt many new techniques, which we are
currently using to investigate the mechanisms of cell competition. I would like to
thank the Company of Biologists for making this partnership possible.