转染血管内皮生长因子基因的小鼠NIH3T3细胞移植促进皮瓣早期血运重建的研究

目的探讨转染血管内皮生长因子（VEGF）基因的小鼠NIH3T3细胞移植对缺血皮瓣的血管新生和皮瓣存活率的影响。方法体外PcDNA3．1（-）／VEGF165质粒转染小鼠NIH3T3细胞,免疫组化方法检测小鼠NIH3T3细胞体外表达VEGF的情况,CM-DiI标记小鼠NIH3T3细胞。将小鼠随机分为3组：A组PcDNA3．1（-）／VEGF165质粒转染的NIH3T3细胞移植]、B组（单纯NIH3T3细胞移植）、C组（单纯DMEM培养基注射）。每只小鼠背侧皮下按组分别注射细胞悬液和培养基,注射后酶联免疫吸附（ELISA）法连续检测大鼠血浆VEGF浓度,注射后第4天掀起一个蒂在尾侧的4．0cm×1．5cm的随意皮瓣。术后第7天分别观察皮瓣的存活率、血流灌注、皮瓣毛细血管密度、NIH3T3细胞在皮瓣内的分布和存活情况。结果转染VEGF165基因的小鼠NIH3T3细胞体外和体内检测均高表达VEGF165蛋白。A组的皮瓣存活率、毛细血管密度、血流灌注比值均显著高于另外两组（P〈0．05）。结论转染VEGF基因的小鼠NIH3T3细胞皮下移植可促进缺血皮瓣的血管新生,提高存活率。

Effects of mouse NIH3T3 cells transfected with VEGF gene on neovascularization of ischemic flaps

OBJECTIVE: To investigate the feasibility of applying NIH3T3 cells transfected by VEGF gene to the treatment of ischemic random skin flaps. METHODS: Plasmid PcDNA3.1(-)/VEGF(165) containing VEGF gene was transduced into the mouse NIH3T3 cells by liposome. Immunohistochemistry was used to detect the expression of VEGF protein of mouse NIH/3T3 cells in vitro. The NIH3T3 cells were stained with CM-DiI before the transplantation. Thirty mice were randomized into 3 groups: Groups A, B and C, and were respectively injected with NIH/3T3 cells transfected with PcDNA3.1(-)/VEGF(165) plasmid, NIH/3T3 cells and medium only. On the 4th day after the injection, random dorsal skin flaps with an area of 4.0 cm x 1.5 cm were established. The survival, neovascularization and blood flow recovery of the flaps were detected. RESULTS: VEGF-transduced NIH3T3 cells expressed VEGF highly in vitro and in vivo. The results showed that flap survival rate in group A (95.1% +/- 3.1%) was significantly higher than those in group B (37.4% +/- 6.3%) and group C (26.2% +/- 5.6%). The capillary density and the blood perfusion of the flaps in group A were significantly higher than those in other two groups. CONCLUSIONS: VEGF-transfected NIH3T3 cells can improve ischemic flap neovascularization and extend survival areas.