Controlling cell-matrix traction forces by extracellular geometry

TL;DR

This paper introduces a minimal active contractile media model to study how extracellular geometry influences cell traction forces, revealing that adhesion patterning controls stress distribution and correlates with cell shape and substrate stiffness.

Contribution

The study provides a new continuum model linking adhesion geometry to traction stress distribution, aligning with experimental observations and offering analytical insights.

Findings

Cell spread area increases with substrate stiffness.

Traction stress correlates with cell boundary curvature.

Patterning adhesion regions controls stress distribution.

Abstract

We present a minimal continuum model of strongly adhering cells as active contractile isotropic media and use the model to study the effect of the geometry of the adhesion patch in controlling the spatial distribution of traction and cellular stresses. Activity is introduced as a contractile, hence negative, spatially homogeneous contribution to the pressure. The model shows that patterning of adhesion regions can be used to control traction stress distribution and yields several results consistent with experimental observations. Specifically, the cell spread area is found to increase with substrate stiffness and an analytic expression for the dependence is obtained for circular cells. The correlation between the magnitude of traction stresses and cell boundary curvature is also demonstrated and analyzed.