Abstract: Objective To evaluate the effects of bone marrow-derived mesenchymal stem cells(BMSC) transplantation on survival of prefabricated flap with increased neovascularization in a rabbit model.Methods BMSCs of New Zealand rabbits were isolated and cultured in vitro.The third passage cells were labeled before transplantation.Two prefabricated flaps of each rabbit were randomly allocated to experiment group or control group.In all animals,the subcutaneous tissue around the tunnel was injected with BMSCs in experiment group,or saline in equal amounts in control group.One week later,one flap from each group was selected to observe the viability of BMSCs.Two weeks later,abdominal island flap based solely on the implanted vessel was elevated.Three flaps were selected from each group to observe the expression of VEGF by Western Blot.Four flaps were selected from each group to observe the signal of vWF and BrdU by immuno-fluorescence histochemical staining.Results BMSCs were found viable in the flap from the experiment group.There was a significant increase in mean survival rate of prefabricated flaps from the experiment group compared to the control group: BMSCs(93.1±2.6)% vs.saline(51.5±7.5)%(P<0.01).Immuno-fluorescence histochemical staining found the signal of vWF in the cytoplasm of BrdU positive cells.Western Blot semi-quantitative analysis showed that the The VEGF protein level was found significantly higher in the tissues from the experiment group than that from the control group.Conclusion The findings from this study demonstrated that BMSCs transplantation could promote neovascularization and improve prefabricated flap survival.

Key words: Mesenchymal stem cells, Transplantation, Prefabricated flap, Vascular endothelial growth factor