Local shear induces long-range suppression of cellular motion in stiff epithelial monolayers
As small particles skim our airways during breathing, or our intestines during digestion, the surface epithelium is subjected to local exogenous shear that deforms hundreds to thousands of tightly interacting cells. Unlike shear deformations applied at the macro-tissue scale or the micro-cell scale, the effects of such perturbations at the meso-scale remain largely unexplored. To address this, we developed a mesoscopic probe that adheres to the apical surface of an epithelial monolayer and applies magnetically driven local shear. We find that localized shear suppressed cellular migratory dynamics far beyond the immediate neighbors in stiffer layers, whereas in softer layers the same perturbation produced no detectable long-range change in dynamics. This mechano-transductive relationship is further supported by unconfined mature layers, in which increased stiffness was accompanied by restored shear responsiveness. Viewed at the level of collective dynamics, shear-induced migratory suppression in stiff layers was often accompanied by reduced MSD scaling exponents and changes in cell shape, but these responses were not fully captured by the epithelial jamming framework. Together, these observations provide a new perspective on how a local mechanical perturbation traverses the epithelial monolayer to influence both nearby and distant cellular environments.