Collective cell migration driven by mechanical coupling

Cells in multicellular organisms migrate during physiological processes such as tissue formation, regeneration, and immune defense. In their natural environment in vivo, cells closely interact with their surrounding tissue and the extracellular matrix (ECM) - a dynamic structure essential for mechanical support. Given the extensive contact between the cells and the surrounding tissue, we ask how the mechanical coupling between the cell and the substrate facilitate collective cell migration. We will discuss experimental evidence, a computational model verified with experimental observations and predicted principles linking collective cell migration to cell-substrate mechanical coupling. We show that cell stiffness is dynamically reduced in response to the temporal stiffening of the substrate, with consequent collective cell migration well characterized by the stiffness ratio between the cell and the substrate. On the basis of computational predictions tested by experiments, we provide evidence that an optimal cell-to-substrate stiffness ratio is important in allowing for collective cell migration rather than a fixed value of substrate stiffness.