Fig. 2: Nuclear deformation promotes osteogenic differentiation of hMSCs.

a Staining of nucleus (green) and F-actin (red) of hMSCs on flat and micropillar mPOC/HA surfaces. Insert: high magnification of cell nucleus. Dashed lines indicate micropillars. b Analysis of nuclear shape index of hMSCs. n = 117 (flat) and 132 (pillar) collected from 3 biological replicates, ****p < 0.0001. c Orthogonal view of cell nucleus on flat and micropillar surfaces. d Nuclear volume analysis based on 3D construction of the confocal images of cell nuclei. n = 35 cells collected from 3 biological replicates, ****p < 0.0001. e Initial cell adhesions on flat and micropillar surfaces. n = 5 biological replicates, N.S., no significant difference. f SEM images show the cell adhesions on flat and micropillar mPOC/HA surfaces. g Live/dead staining of hMSCs on flat and micropillar surfaces at 72 h in osteogenic medium. h Cell metabolic activity of cells on flat and micropillar surfaces tested by a MTT assay. n = 5 biological replicates, ****p < 0.0001. i Cell proliferation tested via DNA content after 72 h induction. n = 5 biological replicates, N.S., no significant difference. j ALP staining of hMSCs on flat and micropillar surfaces after 7 d induction. k ALP activity test of cells after 7 d osteogenic induction. n = 3 biological replicates. l Blot images of osteogenic marker OCN and RUNX2 in cells cultured on flat and micropillar implants. GAPDH is shown as a control. Quantification (m) OCN and (n). RUNX2 according to Western blot tests. n = 3 biological replicates, ****p < 0.0001. Data are presented as mean ± SD. Values from two groups were compared using a non-paired Student’s t-test (two-sided). Source data are provided as a Source Data file.