BMP-2 GENE TRANSFECTED HUMAN BONE MARROW MESENCHYMAL STEM CELLS INDUCING IN VIVO ECTOPIC OSTEOGENESIS OF NUDE MICE

Objective To evaluate the osteogenic potential of human bone marrow mesenchymal stem cells (MSCs) transferred with human bone morphogenetic protein 2(BMP 2) gene by adenovirus. Methods The MSCs were isolated from human bone marrow and cultured in vitro. They were divided into 3 groups: Adv hBMP 2 transduced group; Adv βgal transduced group; untransduced group. Western immunoblot analysis, alkaline phosphatase(ALP) staining, Von Kossa staining, and a quantitative ALP activity assay were performed. Nine nude mice received injection into a thigh muscle to test the osteoinductivity of the three types of cells. Results In the Adv hBMP 2 transduced group, Western immunobolt analysis on tissue culture demonstrated that these cells indeed produced the BMP 2 protein; most MSCs were stained positively for ALP activity 9 day after transduction; the MSCs reached the peak of ALP activity 12 day after transduction; the calcified nodes formed 21 days after transduction. The ectopic bones formed in the thigh muscles of the nude mice. Little bone formation was observed in the other groups 4 weeks after cell injection. Conclusion Adenovirus mediated hBMP 2 gene transfection can induce osteogenesis of human bone marrow mesenchymal stem cells.