Abstract: Objective To investigate the osteogenic potential for size-critical bone defect of fibrin sealant combined with recombined human bone morphogenetic protein-2 (rhBMP-2) grafting and varied autologous bone marrow mesenchymal stem cells (BMSCs) implanting in vivo. Methods BMSCs were cultured and induced with osteogenic supplement (OS) medium. BMSCs with and without OS induction were collected and percutaneously autologous injected respectively into the 15 mm bone defect of experimental rabbit model. The grafts were BMSCs, osteo-induced BMSCs, BMSCs and osteo-induced BMSCs, BMP combined with fibrin sealant, 0.9% NaCl solution. Osteogenesis at the defect area was assessed with regular radiography, histology and biomechanics. Results The FS/BMP group and the BMSCs+osteo-induced BMSCs group achieved complete bone healing with medullary cavity united, with the most new bone formation and the maximal load among those groups. Conclusion The osteogenic potential of both osteo-induced BMSCs combined with BMSCs and FS/BMP are similar, which are superior to that of BMSCs or osteo-induced BMSCs along.

Key words: fibrin sealant, bone morphogenetic protein-2(BMP-2), bone marrow mesenchymal stem cells (BMSCs), cells implanting, bone defection