CO-TRANSFECTION OF RAT BONE MARROW MESENCHYMAL STEM CELLS WITH HUMAN BMP2 AND VEGF165 GENES

Objective To explore the feasibility and efficacy of lentivirus-mediated co-transfection of rat bone marrow mesenchymal stem cells (MSCs) with human vascular endothelial growth factor 165 (hVEGF165) gene and human bone morphogenetic protein 2 (hBMP2) gene. Methods The hVEGF165 and hBMP2 cDNAs were obtained from human osteosarcoma cell line MG63 and cloned into lentiviral expression vectors designed to co-express the copepod green fluorescent protein (copGFP). The expression lentivector and packaging Plasmid Mix were co-transferred to 293TN cells, which produced the lentivirus carrying hVEGF165 (Lv-VEGF) or hBMP2 (Lv-BMP), respectively. MSCs of Wistar rats were co-transfected with Lv-BMP and Lv-VEGF (BMP+VEGF group), or each alone (BMP group and VEGF group), or with no virus (Control group). The mRNA and protein expressions of hVEGF165 and hBMP2 genes in each group were detected by real-time PCR and enzyme linked immunosorbent assay (ELISA). Results Lentiviral expression vectors carrying hVEGF165 or hBMP2 were correctly constructed and confirmed by restriction endonucleses analysis and DNA sequencing analysis. A transfer efficiency up to 90% was archieved in all the transfected groups detected by the fraction of fluorescent cells using fluorescent microscopy. From the results generated by real-time PCR and ELISA, VEGF165 and BMP2 genes were co-expressed in BMP+VEGF group. No significant difference of BMP2 expression was detected between BMP+VEGF and BMP groups (P0.05). Similarly, there was no significant difference of VEGF165 expression between BMP+VEGF and VEGF groups (P0.05). Conclusion VEGF165 and BMP2 genes were successfully co-expressed in MSCs by lentivirus-mediated co-transfection, which provided a further foundation for the combined gene therapy of bone regeneration.