Epithelial homeostasis: mechanics and biology as neighbourhood watch.

Epithelia constitute many of the principal barriers in metazoan bodies and are also common sites for disease, notably cancer and inflammation. Yet, the incidence of epithelial disease is remarkably low, given their constant exposure to injurious agents. By implication, epithelia must have ways to detect potential disturbances – such as those that lead to apoptosis - and deal with them. In this talk, I’ll discuss some of our recent efforts to understand how epithelial cells survey their neighbourhood to detect apoptotic cells. Such surveillance involves a hierarchy of mechanisms: mechanotransduction as a first-response that allows epithelia to physically expel apoptotic cells; and inflammatory pathways that are provoked when physical expulsion fails. Conversely, I’ll consider how aberrant tissue mechanics may disrupt these homeostatic processes.