Experimental research on the adult human bone marrow mesenchymal stem cells differentiating into osteoblasts

Abstract

Objective To establish an ideal culture method on the differentiation of the adult human bone marrow mesenchymal stem cells(BMSCs)to osteoblasts in vitro. Methods The bone marrows were obtained bv aspiration from healthy volunteers.BMSCs were isolated and purified by modified ficoll density gradient centrifugation combined with adherence culture method. MSCs were induced to osteoblasts in vitro in a condition medium in subculture including dexamethasone,vitamin C,and β-glycerophosphate. The morphological changes and growth characteristics were examined by phase-contrast microscopy. Cell surface markers CD34 and CD45 were tested by flow cytometric analyses. Alkaline phosphatase activity and expression of type I collagen were also studied.Results Adult BMSCs presented active proliferation in primary and passage cultures in vitro.Cells were spindleshaped.The cell surface markers CD34 and CD45 were positive before differentiation and were negative after differentiation. Cells were successfully induced into osteoblasts. They were identified through morphological character,specific surface antigens and osteogenic differentiation. Immunochemical expression of type I collagens of the differentiated cells revealed the characteristics of osteogenic differentiation with strong staining.Alkaline phosphatase activity were increase. Conclusion The osteoblasts could be induced from human BMSCs,which have typically morphological and biological characteristics of osteoblasts. Key words: Bone marrow mesenchymal stem cell; Osteogenesis; Differentiation