Propagating Waves of Directionality and Coordination Orchestrate Collective Cell Migration
Figure 2
Wave of coordination of DA3 tumor cells.
The wound healing process was divided into three phases [29]: Phase 1 – free front propagation until first contact between cells from the opposing fronts of the wound. Phase 2 – front matching until full closure of the voids. Phase 3 – post wound closure. (A) Visualization of the wave of coordination during the 3 phases of the healing process: cell clusters migrating with coordinated trajectories are overlaid on the initial time frame of each healing phase. Raw zoomed-in images of each healing phase are found below. (B–C) Waves of coordination for control (B) and HGF/SF-treated (C) cells. Histograms of coordination, measured by the fraction of cells that move in coordinated clusters, in relation to the distance from the edge, accumulated over all experiments. For all following analysis only Phase 1 is considered. (D–G) Spatiotemporal wave of coordination. Coordination was measured in high temporal resolution by clustering a grid of short (72.5 minutes or 5 frames long) trajectories using the same clustering algorithm as in (B–C). The average coordination at time (t) and distance (d) from the wound edge is shown in color code for every bin (t,d) in the map. (D) and (F): spatiotemporal maps (kymographs) for control (D) and HGF/SF-treated (F) cells. In both cases a wave of coordination is observed, and is significantly amplified as a response to HGF/SF treatment. (E) and (G): the average coordination for four 100-minute time intervals of the spatiotemporal maps (D) and (F) respectively. Different time is due to variance in initial wound width and healing rate.