经冠状动脉自体骨髓间充质干细胞移植治疗小型猪急性心肌梗死

Autologus Bone Marrow-derived Mesenchymal Stem Cells Intracoronary Delivery after Acute Myocardial Infarction in Miniature Pig

目的评价经冠状动脉移植体外分离培养自体骨髓间充质干细胞(MSCs)治疗急性心肌梗死(AMI)的可行性及疗效。方法通过结扎冠状动脉左前降支90min后恢复血流的方法建立AMI模型。采用密度梯度离心法分离骨髓单个核细胞、传代培养后,在AMI造模10～14d后将培养扩增的自体MSCs经冠状动脉植入梗死区,应用超声心动图观察移植前后心功能变化情况,冰冻切片荧光显微镜示踪4'G6-二脒-2-苯基吲哚(DAPI)标记的MSCs,Ⅷ因子免疫荧光染色测定新生血管数目。结果MSCs生长呈纺锤样,生长旺盛呈旋涡样;DAPI标记率为100%。AMI造模10～14d后MSCs移植数量平均为(4～6)×107个,移植术后3个月,MSCs治疗组与对照组比较,左心室射血分数(LVEF)显著升高[(54.65±3.39)%vs(43.98±4.21)%(P<0.01)],可见DAPI标记胞核为蓝色荧光的移植细胞,MSCs治疗组与对照组比较,新生血管数目显著升高[(13.28±4.39)vs(4.27±2.28)个G(P<0.01)]。结论通过体外培养扩增在短期内可以获得相当数量的生物性状稳定的MSCs,在AMI造模10～14d后进行经冠状动脉MSCs自体移植,促进左室功能的恢复。MSCs移植与目前广泛运用的介入治疗相结合,方法简便、经济、有效,可望改善AMI患者的预后,具有良好的临床应用前景。

Objective To evaluate the possibility that using intracoronary delivery of autologus bone marrowderived mesenchymal stem cells （MSCs） to improve the cardiac function after acute myocardial infarction （AMI） in miniature pig. Methods MSCs were cultured in Dulbecco＇s modified Eagle＇s medium-F12 （DMEM/F12） medium. AMI model was made by blocking the blood stream of the first diagonal branch in miniature pig, and released the branch after 90 minutes. After 10-14 days, （4-6）×10^7 culture-expanded autologus 4＇, 6-diamidino-2- phenylindole （DAPI）-labelled MSCs were transplanted into each host heart＇s AMI area through intracoronary way. Ultrasonic cardiography （UCG） was performed to observe the left ventricular function at 3 months after transplantion. The cellular transplanted hearts were harvested and investigated by immunohistochemical analysis. Results Left ventricular function of the MSCs group was improved significantly 3 months later compared with the control group [（54.65 ±3.39） vs（43.98±4.21）%, （ P〈0.01）]. Exogenous MSCs survived and site-differentiatod into cardiomyocytes in infracted hearts. Conclusion MSCs can play a benificial role to repair damaged heart. Heart function can be improved after MSCs transplantation in porcine myocardial infarction model.