Abstract: Objective: To construct lentiviral vector carrying bone morphogenetic protein4, and to detect the odontogenic effects on rat bone marrow mesenchymal stem cells for tissue- engineered tooth seed cells. Methods: hBMP4 cDNA was gained by RT-PCR from the mRNA ,which was extracted from mature human placenta. Then it was cloned into plenti6/v5-D-TOPO vector. Lentiviral vectors carrying BMP4 were constructed to transfect rat bone marrow mesenchymal stem cells(BMSCs). The RNA was extracted using real-time quantitative PCR to detect the changes mRNA levels of collagen I, enamel protein,dentin matrix protein 1, and homeobox gene 1. And the proliferation ability of BMSCs was detected with MTT method before and after transfection. Results: After transfection, mRNA levels of collagen I, enamel protein and dentin matrix protein 1 were higher, and the difference was statistically significant (P<0.05),but the mRNA levels of homeobox gene 1 were not significant different, and the proliferation ability was increased. Conclusion: BMP4 is able to improve the proliferation and odontogenic differentiation potential of BMSCs in vitro.

Key words: Bone morphogenetic protein 4, Bone mesenchymal stem cells , Lentiviral vectors , Tissue- engineered tooth, Real-time fluorescent quantitative, PCR