Description
In this talk, we investigate the mechanisms by which organs acquire
their functional structure, realize its maintenance over time and rebuild their
architecture after injury. We do this by means of two-dimensional Individual
Based Models (IBM) of interacting cells and extra-cellular-matrix fiber
elements. The mechanical model first shows that the emergence of organized
structures could be explained by simple mechanical interactions between the
cells and the collagen fibers. Our assumption is that the fiber network resists
the pressure induced by the growing cells and forces them to regroup into
clusters. Reciprocally, cell clusters force the fibers to merge into a
well-organized network. When applied to adipose tissues, the model produces
structures that compare quantitatively well to the experimental observations and
seems to indicate that cell clusters could spontaneously emerge as a result of
simple mechanical interactions between cells and fibers and surprisingly,
vasculature is not directly needed for these structures to emerge. In the second
part of the talk, we extend this model to account for mechanisms of tissue
repair after injury, and use it to explore the mechanisms responsible for
adipose tissue regeneration. The model successfully generates regeneration or
scar formation as functions of few key parameters, and seems to indicate that
the fate of injury outcome could be mainly due to extra-cellular (ECM) matrix
rigidity. Altogether, these studies point to the essential role of mechanics in
tissue structuring and regeneration, and bring a comprehensive view on the role
of ECM crosslinking on tissue architecture emergence and reconstruction.
