Figure 6. Exosomes are successfully isolated from the supernatant of hMSCs. (A) the characterization of surface antigens of hMSCs, detected by flow cytometry. (B–C) the adipogenic differentiation of hMSCs stained with Oil Red O. (C) the osteogenic differentiation of hMSCs stained with Alizarin red S. Green, arrows indicate positive cells (Scale bar = 50 μM). (D) the characterization of exosome structure under the electron microscope (Scar bar = 200 nm). (E) the identification of the exosome surface marker CD63 by Western blot assay. * p < 0.05. The results were measurement data, presented as mean ± standard deviation. Paired t-test was used for the analysis in E. The experiment was repeated three times.