Séminaire du LPTMS: Sam Safran

Non-linearities and interactions of cells with their mechanical environment

Sam Safran
Dept. Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel

Many experiments have shown that the elastic substrates upon which cells are placed or the extracellular matrix (ECM) in which cells reside in 3D can regulate cellular structure and function. From fate “decision making” of stem cells to rigidity-driven motion, cells actively sense and transduce elastic signals, which in turn depends on the elastic properties of the substrate or ECM. We review experimental evidence to demonstrate that cell structure and function is regulated by its mechanical environment (the presence of other cells, external stretch, matrix rigidity) and present a generic, theoretical model for cell response that combines mechanics and cell activity. We predict that even symmetric cells on or in isotropic substrates interact elastically, in contrast to the vanishing interactions for the case of “dead inclusions” under these situations. The theory is extended to the biologically relevant case of “strain stiffening”, non-linear , elastic substrates where the local cell deformations are amplified far from their origin. Finally, we show how cell deformations can orient the surrounding medium which in turn, can provide guidance cues for cell motility.

Date/Time : 04/11/2014 - 11:00 - 12:00

Location : LPTMS, salle 201, 2ème étage, Bât 100, Campus d'Orsay