人脐血内皮祖细胞治疗裸鼠心肌梗死

目的 探讨人脐血内皮祖细胞(EPCs)移植治疗裸鼠心肌梗死的可行性.方法 采用淋巴细胞分离液提取人脐血单个核细胞(MNCs),应用添加诱导因子的培养基于体外诱导分化并于培养7 d后进行鉴定.采用20只裸鼠建立心肌梗死模型后,将体外诱导分化7 d并摄取CM-Dil的内皮祖细胞通过尾静脉注射进行细胞移植到实验组,对照组注射培养基.2周后计数心梗区域新生毛细m管密度及心梗面积并于荧光显微镜下观察新生血管的荧光.结果 体外诱导7 d后贴壁细胞CD34阳性率达(50.48±5.17)%,CDl33阳性率达(19.12±4.37)%.实验组平均梗死面积为(8.27±1.64)%,对照组为(14.30±2.84)%(t=-4.78,P<0.05);实验组每高倍视野平均新生血管密度为14.29±1.38,对照组为10.17±1.72(t=4.71,P<0.01);行荧光显微镜下观察实验组新生血管有红色荧光.讨论人脐血单个核细胞在体外诱导分化为内皮祖细胞,进行细胞移植到建立心梗模型的裸鼠后可在心梗区域形成新生血管,从而并改善梗死部位心脏功能.

Transplantation of endothelial progenitor cells from human cord blood into ischemic myocardium of nude mice

Objective To investigate the possibility of endothelial progenitor cells (EPCs) trans-plantation for the treatment of myocardial infarction of nude mice. Methods Mononuclear cells (MNCs) were isolated by lymphocyte separating medium from human cord blood and were cultured in DMEM with proper inducing factors. After 7 days, the attached cells were identified by the characteristic of EPCs. After establishing myocardial infarction model of 20 nude mice the attached cells taking CM-Dil were injected into vena caudalis. The control group was injected with non-serum culture medium, nfarcted size, apillary den-sity and fluorescence of new capillaries were measured 2 weeks after operation. Results After 7 days, the CD34 positive rate in the attached cells was (50.48±5. 17)% and CD133 rate was (19. 12±4. 37)%, respectively. Two weeks after operations, infarcted sizes of transplantation group was significantly reduced [(8. 27 ± 1.64 ) % vs (14. 30 ± 2. 84 ) % (t = -4. 78, P < 0. 01)] and capillary density increased [(14.29 ± 1.38 vs 10. 17 ± 1.72) (t =4. 71 ,P <0. 01 )] as compared with those in control group. Red fluorescence of new capillaries in transplantation group was found. Conclusion Under proper culture con-ditions, mononuclear cells from cord bloods can develop into EPCs, and transplantation of EPCs into the infarcted regions of nude mice can generate new capillaries to improve heart function.