Bistability of cellular traction on strain-stiffening substrates

To migrate, cells exert traction forces on the extracellular matrix (ECM) -- a biopolymer network that often exhibits nonlinear strain-stiffening elasticity. Cellular tractions can therefore stiffen the ECM. At the same time, cells exert stronger tractions on stiffer ECM. Here, we show theoretically that this traction-stiffness feedback can produce traction bistability and hysteresis. As a result, increasing either the ECM's nonlinear elasticity or cellular contractility leads to a discontinuous transition from low to high tractions. This traction jump might trigger collective cell migration as the ECM stiffens, for example during development and tumor progression. Moreover, the bistable behavior might provide robustness to cellular traction forces when cells migrate through mechanically heterogeneous environments.

Source: arXiv:2606.03669v1 - http://arxiv.org/abs/2606.03669v1 PDF: https://arxiv.org/pdf/2606.03669v1 Original Link: http://arxiv.org/abs/2606.03669v1