Abstract

Biological phenomena ranging from morphogenesis to tumor progression inherently generate shear stresses within living tissue. However, the mechanisms that facilitate the transmission of these mechanical forces within epithelia and enable the tissue’s collective response to bulk shear deformations are not fully understood. My talk aims to explore these complex processes using a simplified, cell-based computational model to understand the behavior of confluent tissues subjected to simple shear deformation. Our study illustrates how an initially uniform, fluid-like tissue gains significant rigidity once the applied strain exceeds a critical level, echoing similar patterns observed in various soft matter systems. More interestingly, when focusing on the rheological response of a tissue near this critical point of shear-induced rigidity, we discover a fascinating interplay between internal active forces and an externally imposed shear. This interaction gives rise to a variety of unique rheological behaviors, such as yielding, shear thinning, continuous shear thickening, and discontinuous shear thickening.