OBJECTIVETo compare the effect of local administration of endothelial progenitor cells (EPCs) and VECF on improving neovascularization and augmenting the survival areas in a rat model of prefabricated flap.

METHODSPrefabricated flaps were created by ligating the right femoral vascular pedicle and implanting it underneath the abdominal flap. The in vitro cultured EPCs (Group I , n=15) and VEGF protein (Group II , n=15) were injected subcutaneously around the implanted pedicle in experimental groups. PBS was injected in control group (Group Ill , n=15). 4 weeks later, the abdominal island flap based solely on the implanted vessels was elevated and sutured back. Then flap viability and numbers of capillary were evaluated on day 7.

RESULTSThere was more statistically significant augmentation of flap survival [(87.26 +/- 10.13) % versus (66.13 +/- 9.9)% and (55.59 +/- 13.06)%, P < 0.001], a higher capillary density (38.67 +/- 9.52 versus 25.83 +/- 6.33 and 26.5 +/- 5.61 capillary/mm2 , P < 0.05) in EPCs group than in the other two groups.

CONCLUSIONSEPCs are superior to VEGF in improving neovascularization during flap prefabrication. Local transplantation of bone marrow-derived EPCs may be a useful strategy for augmentation of the survival areas of prefabricated flaps.