Effect of vascular endothelial growth factor gene transfer on proliferation and metabolism of human bone marrow stromal cells in vitro

Objective To investigate the effect of vascular endothelial growth factor 165 (VEGF165) gene transfer on the proliferation and metabolism of human bone marrow stromal cells (hBMSCs) in vitro. Methods hBMSCs were divided into 3 groups and subjected to adenovirus mediated VEGF165 gene transfection, transfection with empty adenoviral vector, or left untreated (control). MTT assay and flow cytometry were performed to analyze the proliferation of the cells after corresponding treatments. The third passage of hBMSCs (2×104/ml), after corresponding transfection procedures, were cultured in conditional medium and tested for ALP content 2, 4 and 6 days after the transfection. Also at 3, 5 and 7 days after the transfection, the cells were examined for osteocalcin (C) and laminin (LN) contents. Results The number of cells in each group increased with the culture time without obvious differences in the optical density. No significant differences were noted between the 3 groups in the percentage of G1 phase cells or in the proliferation index (PrI) (P0.05), but compared with the nontransfected and the empty vector-transfected cells, the cells with VEGF165 gene transfection had significantly higher ALP, OC and LN contents (P0.05). Conclusion VEGf165 gene transfer does not obviously affect the proliferation of cultured hBMSCs, but can increase the cellular secretion of AIP, C and LN, suggesting that VEGF165 promotes the differentiation of hBMSCs into osteoblasts in vitro.