移植转染ADM或HGF基因的骨髓间充质干细胞治疗大鼠心肌梗死

Effects of transplantation of mesenchymal stem cells combining with ADM or HGF gene in the treatment of myocardial infarction in rats

目的探讨移植转染两种不同基因的骨髓间充质干细胞移植治疗大鼠心肌梗死的作用。方法分离、扩增培养大鼠骨髓间充质干细胞;ELISA检测细胞上清液ADM或HGF的含量;制备大鼠心肌梗死模型,心肌局部注射移植经DAPI标记的MSCs;多普勒超声检测大鼠心功能;荧光显微镜观察细胞存活及分布;免疫组化检测新生血管密度及移植细胞在心梗区的分化。结果转染Ad-ADM或Ad-HGF后,MSCs可有效表达ADM或HGF;与单纯MSCs组相比,两基因组细胞均表达TNI,均有connexin 43的表达增加(P<0.05),心梗区新生血管密度增高(P<0.01),左室射血分数(EF)增加(P<0.01);两组间各指标无差别。结论不同基因修饰的MSCs移植均可增强单纯MSCs对心肌梗死大鼠的治疗作用。

Objective To investigate effects of transplantation of mesenchymal stem cells combining with two different gene transfection on the treatment of myocardial infarction in rats. Methods MSCs were isolated and expanded using the preplating method. Ad-ADM or Ad-HGF expression in MSCs and its secretion in culture medium were measured by ELISA. The left anterior descending branch of rats was ligated to establish a myocardial infarction model. Then the pretreated MSCs were labeled by DAPI, through injection directly into the infarcted myocardium at open thorax surgery. Four weeks later, cardiac function was evaluated using echocardiography. Hearts were harvested. Immunohistochemistry staining of factor Ⅷ was used to evaluate the density of capillary vessels in infarction area. Immunohistochemistry staining of troponin Ⅰ （TNI） and connexin 43 were used to evaluate the differentiation and expression of implanted MSCs. Fluorescence microscopy was used to identify the DAPI-labeled cells. Results The expression of ADM or HGF was traced in culture medium and has a time-effect relationship. DAPI-labeled transplantion MSCs were founded in the hearts of the recipients and expressed TNI in all MSCs transplantation groups. Immunohistochemical studies demonstrated that intense immunostaining for connexin 43 was higher in Ad- ADM plus MSCs group and Ad-HGF plus MSCs group, compared with MSCs group. A combination of Ad-ADM or Ad-HGF trensfection and MSCs transplantation demonstrated a further increase in capillary density and improved LVEF as compared with MSCs alone. There is no statistical significance between Ad-ADM plus MSCs group or Ad- HGF plus MSCs group in all index. Conchmion Ad-ADM or Ad-HGF transfection enhanced the angiogenic potency of MSCs transplantation and improved cardiac function. The treatment of myocardial infarction in rats in both Ad- ADM plus MSCs group and Ad-HGF plus MSCs group was not able to statistics significance.