Fig. 3

The hSMSCs has lower osteogenic differentiation potential in vitro. a Morphology of the confluence cells was shown (scale bar = 200 μm). b hSMSCs, iMads, and C3H10T1/2 cells were infected with AdGFP and AdBMP2. The ALP activity was measured at 5 days after transfection using ALP histochemical staining (Gross observation) (c). The ALP quantification activity was detected at OD 405 nm and normalized to total protein per well (unit/mg protein). d The mineralization and calcium deposition at the late osteogenic differentiation were observed by Alizarin Red S staining assay (scale bar = 100 μm) (e). Quantification results of Alizarin Red S staining showed that the mineralization effect in BMP2-induced hSMSCs was poor (day 14, normalized to total DNA per well, OD 405 nm/ug DNA). f RT-qPCR assay determined that hSMSCs have the lower expression level of osteogenic relative factors, including RUNX2, Osterix, and Osteocalcin at BMP2-induced osteogenic differentiation. Each experiment was done in triplicate. *P < 0.05, **P < 0.01