重组腺相关病毒载体介导成纤维细胞生长因子2基因诱导缺血心肌血管新生

探讨重组 2型腺相关病毒载体介导 2型成纤维细胞生长因子基因诱导家兔缺血心肌血管生成的作用。实验对象为 2 0只新西兰兔 ,手术建立心肌缺血模型后随机分为成纤维细胞生长因子基因治疗组和对照组 ,分别向缺血区域心肌注射成纤维细胞生长因子腺相关病毒或磷酸盐缓冲液。 4周后取心肌及肝、肾等器官组织标本 ,采用逆转录聚合酶链反应检测目的基因mRNA的表达 ;制作组织学切片以观察组织病理改变 ,于高倍镜下计数缺血区域微血管数目。结果发现转染的 2型成纤维细胞生长因子基因在缺血心肌中有表达 ,成纤维细胞生长因子基因治疗组缺血区域单个高倍视野内的微血管数为 12 .0± 1.4条 ,对照组为 4 .5± 1.5条 ,二者差异具有显著性 (P <0 .0 1)。 2型成纤维细胞生长因子基因治疗组的肝脏、肾脏、脾脏、角膜和睾丸标本中均未发现 2型成纤维细胞生长因子基因的表达 ,病理检查也未发现组织结构异常。说明腺相关病毒载体介导的 2型成纤维细胞生长因子基因可以有效地转染入家兔缺血心肌 ,并具有明显的诱导缺血心肌血管生成的作用 ,且基因表达仅限于心肌。

Recombinant Adeno-associated Viral Vector 2-Mediated Fibroblast Growth Factor 2 Gene Transfer Induces Angiogenesis in Ischemic Heart

Aim To investigate the effect of fibroblast growth factor 2 (FGF2) cDNA mediated by recombinant adeno-associated viral vector2 (rAAV-2) on ischemic myocardium. Methods 20 rabbit myocardial ischemic models were generated by ligation of the anterior descending coronary artery. All these models were randomly divided into 2 groups: FGF2 gene therapy group (1012 v.g./kg) and control group. RAAV-2/FGF2 or PBS was injected into the ischemic myocardium respectively. After 4 weeks, the expression of objective gene mRNA was evaluated by RT-PCR. The histological changes of myocardium and other organs were observed through histological sections. Myocardial capillary counts were calculated to evaluate the proangiogenic effects. Results FGF2 gene expression was observed in rAAV-2/FGF2 treatment group. The microvessel counts of this group and control group were (12.0±1.4)/HPF and (4.5±1.5)/HPF respectively. There was significant difference between two groups(p<0.01). In rAAV-2/FGF2 1012 v.g./kg treatment group, there was no FGF2 gene expression in liver, kidney, spleen, cornea or testis. And no abnormality was detected in tissues structure through histopathological detection. Conclusions FGF2 gene mediated by rAAV-2 can be efficiently transferred into rabbit ischemic heart and induce angiogenesis of myocardium successfully. FGF2 gene expression is limited in myocardium.