Long-range cellular wound response manifests as ebb and flow

We inquire into communication at longer range than can be explained by current understanding of cell extrusion as the joint contribution of pulse-string and lamellipodium at the interface between an extruding cell and its neighbors. Our live-cell optical imaging reveals collective tissue-scale movement provided that damage (from micro-patterned strong laser irradiation) is at multiple spots. With time, bulk elastic behavior causes these multiple spots to merge into a single spot: with inward flow towards the damage at early times, followed by later outward flow, mediated by actomyosin contractility. Using a knock-down expression model, we confirm that this in turn is modulated by mechanosensitive channels, Piezo1 and TRPC1, and also by calcium propagation kinetics.