Ad.VEGF转染自体骨髓基质细胞移植治疗猪慢性缺血性心脏病

Transplantation of VEGF gene transfected autologous marrow stromal cells in a porcine chronic ischemic heart model

目的:观察和评价转染血管内皮生长因子(vascular endothelial growth factor, VEGF)基因的自体骨髓基质细胞移植于猪的慢性缺血模型后对心功能的保护和促血管新生作用。方法:置Ameriod环建立慢性心肌缺血猪模型,随机分为4组:转染VEGF基因的自体骨髓基质细胞组(组Ⅰ,n=9),单纯细胞移植组(组Ⅱ,n=8),单纯基因治疗组(组Ⅲ,n=7),以注射空腺病毒载体的实验动物为对照组(组Ⅳ,n=8)。体外培养自体骨髓基质细胞,Ad.VEGF转染细胞,以CM DiI为标记,移植于该模型猪心脏的缺血区域。观察和分析各实验组Rentrop分数、心脏射血分数(EF)、梗死区的面积百分比、移植细胞成活性、血管密度及VEGF的表达和分泌。结果:模型建成后,所有动物的冠脉造影左旋支(LCx)完全闭塞或闭塞程度大于95%,说明模型构建成功。与其他各组比较,组Ⅰ的Rentrop分数的升高值及心脏射血分数的升高值均有显著性提高(P<0.01),梗死区面积明显减少(P<0.01),具有维持心脏正常功能的几何构型及室壁厚度,且荧光显微镜下可见大量CM DiI标记的移植成活细胞。组Ⅰ、组Ⅲ缺血区血管计数和VEGF在心肌中的蛋白表达高于组Ⅱ、组Ⅳ,组Ⅰ和组Ⅲ组间并无明显差异。结论:携带VEGF基因的自体骨髓基质细胞移植治疗缺血性心脏病具有明显的优越性,移植细胞成活率高,局部血?

Objective:To investigate the protective effects of transplanting VEGF gene transfected autologous marrow stromal cells on cardiac function in a porcine chronic ischemic heart model. Methods: The porcine chronic ischemic heart model was established by placing an ameroid occluder around LCx of Yorkshire pigs. The pigs were randomized into VEGF-transfected marrow stromal cells group(Group Ⅰ, n=9), simple marrow stromal cells group(Group Ⅱ, n=8), simple VEGF group(Group Ⅲ, n=7), and empty vector transfected group(Group Ⅳ, n=8).Cells labelled by CM-DiI were transplanted by direct epicardial injection.Twenty-eight days after initiation of the therapy, the animals were evaluated with Rentrop score(angiographic analysis), ejection factor (echocardiography), the percentage of infarcted area, CM-DiI labelled cells(fluorescence microscopy), vessel density, and VEGF protein expression(Western blot).Results: Angiography showed that all LCx were completely occluded or the occlusion degree exceeded 95%, indicating that the animal model of chronic ischeamic heart disease was established suceessfully.Group Ⅰ had greater improvement in the Rentrop score(P<0.01) and ejection factor(P<0.01) and a smaller infarction area(P<0.01) compared with those of other groups. Fluorescence microscopy showed that Di-I labelled cells were at the site of implantation in Group Ⅰ. Western blot showed the vessel number and the VEGF protein expression were significantly increased in Group Ⅰ and Group Ⅲ compared with Group Ⅱ and Group Ⅳ, while no significant difference was detected between Group Ⅰ and Group Ⅲ. Conclusion: Transplantation of VEGF-transfected autologous marrow stromal cells has a high survival rate in the myocardium and can obviously improve blood supply and cardiac function.