AI Insight
This theoretical study demonstrates that cells can exhibit bistable traction forces when interacting with strain-stiffening extracellular matrix (ECM). The researchers found that a positive feedback loop exists where cellular tractions stiffen the ECM, which in turn causes cells to exert even stronger tractions, leading to discontinuous transitions between low and high traction states. This bistability produces hysteresis effects and can be triggered by increases in either ECM nonlinear elasticity or cellular contractility.
Why it matters
The findings could explain how cells coordinate collective migration during critical biological processes like embryonic development and tumor metastasis as tissue stiffness changes. The bistable mechanism may also provide cells with robust mechanical sensing capabilities when navigating through tissues with varying stiffness, which has implications for understanding cancer spread and designing biomaterials for tissue engineering.
arXiv:2606.03669v1 Announce Type: cross
Abstract: 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: Bistability of cellular traction on strain-stiffening substrates