Laboratoire Matière et Systèmes Complexes

Hydrodynamic instabilities, waves and turbulence in spreading epithelia

Carles Blanch Mercader

Abstract: In the last decades a great deal of attention has been focused on spreading epithelial monolayers, as a model system to study morphogenesis, tissue repairing or cancer invasion. These cellular systems exhibit a rich repertoire of dynamical states, such as propagation of elastic-like mechanical waves at time scales of several hours, where one expects a fluid-like behaviour [1]. In our study, we show that this observation can be conciliated through a minimal hydrodynamical description of a compressible active polar fluid by introducing two sources of activity: traction forces with the environment and intercellular contractile stresses. The physical model harbours a new periodic oscillatory instability controlled by cell-substrate interactions. Near the critical point, the system admits a reduced description given by the Complex Ginzburg-Landau equation that we compute analytically [2]. Thus, we report a full characterisation of all dynamical states, ranging from coherent nonlinear waves to turbulent states. In the last part of the seminar, I will discuss these results in the light of recent experimental findings from P. Silberzan group on collective migration of weakly-adherent epithelial cells [3].

[1] C. Blanch-Mercader, R. Vincent, E. Bazellières, X. Serra-Picamal, X. Trepat, and J. Casademunt, Soft matter, (2017).

[2] C. Blanch-Mercader and J. Casademunt, Soft matter (2017).

[3] G. Duclos*, C. Blanch-Mercader*, V. Yashunsky*, G. Salbreux, JF Joanny, J Prost, P. Silberzan, Nat. Phys. (2018).

Wednesday June 13 at 12:30pm in room 646A