Research of marrow mesenchymal stem cells differentiating into osteoblast cells induced by fibronectin and bone morphogenetic protein-2 in vitro

Objective:To study the single and combined effect of bone morphogenetic protein-2(BMP-2) and fibronectin(FN) on the differentiation of the marrow mesenchymal stem cells(MSCs) into osteoblast cells in vitro.Methods: MSCs obtained from SD rats were cultured,the experiments were investigated into four groups:control normal group;(A)100 μg/ml BMP-2;(B)10 ng/ml FN;(C)100 μg/ml BMP-2 and 10 ng/ml FN.At different time points(3,6,9,12 d),the numbers of the cells were counted and the levels of alkaline phosphatase(ALP) activity were detected;the expression of osteoblastic phenotypes were demonstrated and the speed of cells growth on n-HAC scaffold were also observed by scanning electron micrography(SEM).The differentiation of bone among groups were analysed. Results: After differentiation of MSCs obtained from SD rats.The cells possessed osteoblast morphological properties;the cell numbers and the expression of the ALP increased with cultivating time of the four groups were all changed between group C and others,and group C were most obviously demonstrated.At the same time point compared group C with other groups,the difference had statistical significance(P0.05).Cells could be observed on every by SEM,the properties of cells in group C had significant change. Conclusion: FN combined BMP-2 can effectively induce BMSCs to differentiation and proliferation into osteoblast cells in vitro,It is suggested that interaction between BMP-2 and FN can be used as a better inducer for bone tissue engineering.