Fig. 4

Pg-derived OMVs inhibit osteoblastic differentiation of BMSCs in vitro. A The flow cytometry results of CD29, CD90 and CD45 in the isolated BMSCs. B Oil Red O staining results (scale bar = 200 μm). C Alizarin Red S staining results (scale bar = 200 μm). D Most BMSCs displayed strong intracellular green fluorescence which indicated that Pg-derived OMVs successfully entered BMSCs. Nucleus have been labeled with DAPI (blue), actin filaments have been labeled with DY-554 phalloidin (red), and OMVs have been labeled with PKH67 (green). The bottom white lines represented the scale bar (scale bar = 50 μm). E Flow cytometry result showed the proportion of BMSCs taken up the PKH67 labeled OMVs. F qRT-PCR analysis of ALP, OCN, RUNX2, and BMP2. G, H ALP, OCN, and BMP2 protein expression levels were determined by western blotting. Full-length blots are displayed in supplementary Fig. 3. I ALP activity was detected by ALP staining (scale bar = 250 μm). J Alizarin Red S staining results (scale bar = 250 μm)