Abstract: Objective To evaluate effectiveness of EM>ex vivo/EM> adenoviral gene transfer creating human bone morphogenetic protein 7producing mesenchymal stem cells (Ad-hBMP-7 cells) compounded with nano-hydroxyapatite/collagen(NHAC) composite to induce spinal fusion in a rat posterolateral spine fusion model. Methods Mesenchymal stem cells were cultured and transduced by Ad-hBMP-7. Then Ad-hBMP-7 cells were cocultured with NHAC. Totally 56 Wistar rats were divided into four groups. Intertransverse spinal arthrodesis was attempted in four groups of Wistar rats with autogenous bone (group A); NHAC(group B); NHAC and BMSCs (group C); Ad-hBMP-7 cells and NHAC (group D). Each specimen underwent plain radiography, manual palpation and histological analysis. Results All spines in group D had fusion. In contrast, none of the spines in group A and group B had fusion. Three of ten rats in group C achieved fusion at the 12th week post-operatively.Conclusion BMP-7-producing mesenchymal stem cells compounded with NHAC composite may induce intertransverse fusion in the rat spine model.

Key words: Bone morphogenetic protein 7, Mesenchymal stem cell, Spine fusion, Gene therapy, Western blotting, Rat