Fig. 4

Effect of M2-Exo on osteogenic differentiation of BMSCs in vitro. A: Representative images of Alizarin red staining. B: Statistical results of Alizarin red staining. C: Representative images of ALP staining. D: Statistical results of ALP staining. * Compared with the NM group, *P < 0.05, **P < 0.01, and ***P < 0.001