RESUMO
<p><b>OBJECTIVE</b>To investigate the feasibility of transplanting endothelial progenitor cells (EPCs) transfected with VEGF165 gene to free transplanted fat tissue for increasing neovascularization and the survival.</p><p><b>METHODS</b>EPCs isolated from human cord blood were cultured in vitro and identified by immunocytochemistry. After transfection by VEGF165 gene, the expression of VEGF was assessed using ELISA. Then EPCs with (VEGF gene transfection group) and without VEGF165 gene transfection (EPCs group) were transplanted to free transplanted fat tissue at 18 nude mice's back, and nine nude mice transplanted with free fat tissue were injected with M199 (control group). CM-DiI was used to trace the transplanted cells. The capillary density of transplanted fat tissue was detected by CD34 immunohistochemistry.</p><p><b>RESULTS</b>EPCs expressed cell markers CD34, KDR and CD133. After transfection, the expression of VEGF was positive. Transplanted EPCs survived and proliferated, and transplanted EPCs were incorporated into the capillary networks in the transplanted fat tissue. The percent of survival volume of transplanted fat tissue of VEGF gene transfection group was (96.2 +/- 8.6)%, significantly higher than that of the EPCs group [(75.3 +/- 6.8)%, P < 0.05) and M199 group [(40.2 +/- 2.5)%, P < 0.05). The capillary density of transplanted fat tissue of VEGF gene transfection group was significantly higher than those of the EPCs group and M199 group (P < 0.05).</p><p><b>CONCLUSIONS</b>EPCs from human cord blood can increase free transplanted fat tissue neovascularization and the survival volume, and the ability of promoting neovascularization of EPCs transfected with VEGF165 gene is more potent than EPCs alone.</p>