Fig. 2: Cell morphology of cell migration on substrate with fast cyclic rigidity change.

a Time series of cell outlines from randomly selected hMSCs cultured on PYP hydrogels with different mechanical properties. Scale bar is 50 µm for all panels. b–e Cell area, circularity, roundness, and instantaneous migration speed of individual hMSCs on the PYP hydrogels with different mechanical properties. Representative figures for individual cells are shown in Fig. 2b–e, and additional representative statistics for multiple individual cells are presented in Fig. S8–11. f Quantitative analysis of directions (left) and direction autocorrelation (right) of cell migration on substrate with fast cyclic rigidity change (transitioning between 2.2 kPa and 1.6 kPa, 1 min on/off) and mesenchymal migration on static rigid substrates (Young’s modulus of ~13.0 kPa). In the right panel, data are presented as mean values (central line) +/- standard deviation (shaded region). In f, n = 204 and 219 (1 min cycle and 13.0 kPa) cells were examined, each from 3 independent experiments. g Representative point-scanning confocal images of hMSCs on substrate with fast cyclic rigidity change and static rigid substrates subject to indicated treatments immunostained with antibody against Myosin IIb and Golgi. Scale bar is 50 µm for all panels. h Quantification of Myosin IIb intensity polarity on the two sides and Golgi apparatus distribution angle from hMSCs on substrate with fast cyclic rigidity change and static rigid substrates. In h, n = 208 cells were examined from 3 independent experiments. In h, *** = p < 0.01, unpaired, two-tailed t-test. Source data are provided as a Source Data file.