Fig. 1

Proliferation and differentiation of MMSCs and SMMSCs in vitro. A The MMSCs cells (A[a]) and SMMSCs (A[d]) have similar typical fibroblast-like morphology after cultured 3 days in vitro. The differentiation was induced in MMSCs and SMMSCs for 2 weeks in vitro and progress of adipogenic and osteogenic differentiation was explored by cytochemistry. Osteogenic differentiation by ALP staining (b, e). Adipogenic differentiation was detected by Oil Red O staining (c, f). In contrast to MMSCs, efficient osteogenic differentiation could not be induced in SMMSCs [compare (b) vs. (e)]. The bars extend 100 μm (a-e) and 20 μm (c, f). B MTT assay was performed for cell proliferation after 1, 3, 7, 12 and 15 days culture with passages 5–8 cells of MMSCs and SMMSCs. The results show the cell growth rate of SMMSCs was significantly slower than MMSCs. C osteogenesis and adipogenic quantitative assay in MMSCs and SMMSCs groups. D CFU-f numbers in MMSCs and SMMSCs groups. After 15 days cultured in Mesenchymal Stem Cell Medium, colonies were stained with crystal violet and counted. Data are expressed as mean ± SD from all experiments, as indicated * P < 0.05