转染血管内皮细胞生长因子基因的同种异体骨髓间充质干细胞移植大鼠缺血心肌的实验研究

Transplantation of Allogenetic Mesenchymal Stem Cells Transfected with Vascular Endothelial Growth Factor Gene into Rat Infarcted Myocardium

目的腺病毒介导血管内皮细胞生长因子基因(AdVEGF165)转染同种异体大鼠骨髓间充质干细胞(BM-SCs),移植到大鼠缺血心肌后,观察其对心功能的影响。方法体外培养同种异体大鼠BMSCs,用AdVEGF165转染同种异体大鼠BMSCs,采用ELISA法检测血管内皮细胞生长因子(VEGF)的表达和分泌。结扎Wistar大鼠冠状动脉前降支,4周后随机将其分为4组,组Ⅰ:移植转染后的BMSCs;组Ⅱ:移植单纯BMSCs;组Ⅲ:心肌内注射AdVEGF165(基因治疗);组Ⅳ:心肌内注射DMEM(对照组)。4周后通过超声检查观察心脏射血分数(EF)变化,评价其对心功能的影响;免疫组织化学观察移植的BMSCs在局部存活、分化情况。结果ELISA检测提示:转染后BMSCs的培养上清液中有大量VEGF表达,较未转染组差异有极显著性意义(P<0.01)。超声检查结果提示:组ⅠEF改善幅度较组Ⅱ、Ⅲ、Ⅳ明显(均P<0.01)。免疫组织化学检测提示:组Ⅰ、Ⅱ中大部分移植细胞能够在移植处存活并转化为心肌细胞。结论转染AdVEGF165的同种异体BMSCs能有效修复大鼠心肌,并能改善其心功能。

Objective To observe the effect of transplantation of allogenetic bone mesenchymal stem cells （BMSCs） transfected with adenovirus-mediated vascular endothelial growth factor gene （AdVEGF165） into rat infarcted myocardium on heart function. Methods Allogenetic BMSCs were cultured in vitro and transfected with AdVEGF165. ELISA method was applied to assay the expression and secretion of VEGF. Wistar rats whose left descending branch of coronary artery was ligated, after 4 weeks, were divided randomly into 4 groups. Group Ⅰ . transplantation of allogenetic BMSCs transfected with VEGF gene, group Ⅱ ： transplantation of allogenetic BMSCs alone, group Ⅲ： intra-myocardium injection of AdVEGF165 （gene therapy）, group Ⅳ ： intramyocardium injection of DMEM （control group）. After 4 weeks, eject fraction （EF） change was observed by ultrasound to estimate the impact on heart function. Immunohistochemistry was applied to observe survival and differentiation of transplanted BMSCs in local area. Results ELISA revealed the supernatant in group Ⅰ had a higher level of the VEGF expression than control group （P〈0. 01）. Ultrasound indicated that improvement degree of EF in group Ⅱ was more significant than in groups Ⅱ , Ⅲ and Ⅳ （P〈0. 01）. Immunohistochemistry suggested the majority of implantation cells could survive and differentiate into cardiomyocytes. Conclusion Allogenetic BMSCs which were transferred AdVEGF165 can repair Wistar rats＂ myocardium effectively and improve Wistar rats＂ heart function.