Fig. 1

Characterization of MSCs and MSC-EXs. a Morphology of MSCs, scale bar = 400 μm. b Alizarin Red S staining of osteogenic differentiation of MSCs, scale bar = 50 μm. c–f Analysis of cell surface antigens of MSCs. g Microscopy images of GFP marker expression in MSCs after lentivirus infection, scale bars = 200 μm. h The numbers and size of MSC-EXs were detected by NTA. i TEM was used to detect the size and morphology of EXs, scale bars = 100 nm. j The level of EX-specific marker CD63 and TSG101 was detected by western blot. k Real-time PCR results show the level of miR-132-3p in MSCs and MSC-EXs