Fig. 5.

In vitro osteogenic induction. Human gingival mesenchymal stem cells (hGMSCs), maintained under osteogenic conditions for 6 weeks, were stained using Alizarin Red S solution. a Macro photographs. b Photographs obtained at light microscopy. Scale bars = 5 μm. c Graph optical density. d RT-PCR of osteogenic related markers. e Western blots of RUNX2 and BMP2/4; β-Actin was used as the housekeeping protein. **p < 0.01, versus hGMSCs. EVs, extracellular vesicles; PEI, polyethyleneimine