同种异体移植骨髓间充质干细胞治疗大鼠心肌梗死

目的　探讨同种异体骨髓间充质干细胞 (MSCs)在梗死大鼠心脏局部存活、迁移、分化及对心功能的影响 ;明确同种异体细胞移植治疗心肌梗死 (MI)的可行性及效果。方法　雌性Wistar大鼠 3 5只 ,随机分为正常对照组、急性心肌梗死 (AMI)组及MI MSCs治疗组。分离纯化雄性Wistar大鼠骨髓MSCs ,于左冠状动脉前降支结扎后 1～ 3h植入到雌性大鼠心脏组织 ,移植后 10周检测心功能并取心脏检测各种相关指标。结果　异体大鼠MSCs经纯化后可在梗死心脏组织定居、生存 ,并与宿主心肌纤维排列方向一致 ,免疫组化检测胞质心肌特异蛋白染色阳性 ,与MI组比较 ,异体细胞移植组左室收缩压升高 (P <0 0 5) ,舒张末压明显降低 (P <0 0 1)、左心室内压最大上升和下降速率显著增快 (P <0 0 5) ,梗死边缘区心肌面毛细血管数目明显增加 (P <0 0 5) ,多功能真彩色病理图像分析系统显示MI面积缩小 (P <0 0 5)。结论　同种异体MSCs移植治疗MI可行、有效

Transplantation of exogenous mesenchymal stem cells for treatment of myocardial infarction in rat

OBJECTIVE: To investigate the possibility of homing,survival, migration and differentiation of rat mesenchymal stem cells (rMSCs) in host myocardium and the effects of rMSCs transplantation on the function of heart with myocardial infarction; To observe the feasibility of using exogenous adult stem cells for cell therapy. METHODS: 35 female rats were separated randomly into three groups: normal control group (control, n = 10), acute myocardial infarction control group (AMI, n = 10) and myocardial infarction plus cell transplantation group (AMI + Cell, n = 15). The infarcted hearts were made by occlusion of left coronary artery. Male Wistar rats MSCs were isolated and purified. Then the cells were implanted into the infarcted hearts of female Wistar rats. Heart functions were measured 10 weeks after implantation. The hearts were harvested 10 weeks after implantation for immunohischemistry. RESULTS: (1) Purified rMSCs survived and homed in exogenous host hearts; (2) DAPI-labelled rMSCs with oval nucleus were widely distributed and stained positively of cardiac specific proteins. The arrangements of the donated cells paralleled with host myocardium fibers in infarcted host hearts. Transplantation of rMSCs was associated with a significant decrease of end left ventricular volumes, increase of left ventricular end-systolic pressure and increase of ratio of left ventricular pressure rise and left ventricular pressure decay (+/- dp/dt) (P < 0.05) as compared with the control hearts. The numbers of blood vessels were increased at the boundary of infarction site and the sizes of infarction were decreased significantly (P < 0.05). CONCLUSIONS: The purified rMSCs can survive in exogenous host hearts without addition of any immunosuppressant. These exogenous cells take part in myocardium regeneration and have beneficial effects on heart function.