自体内皮祖细胞移植修复兔动脉内皮损伤

Transplantation of Autologous Endothelial Progenitor Cells for Repair of Injured Vessels in Rabbits

目的观察不同数量的内皮祖细胞移植对内膜球囊损伤血管修复的影响。方法密度梯度离心法分离兔外周血单个核细胞,以EGM-2培养基培养7天,获得兔外周血内皮祖细胞。分高细胞数量移植组(5×105个细胞)和低细胞数量移植组(2×105个细胞),将相应数量的内皮祖细胞重悬于100μL生理盐水中移植至兔内膜球囊损伤血管局部,对照组仅注入100μL生理盐水。同时用CM-DiI标记内皮祖细胞移植,进行细胞示踪。4周后,处死动物,荧光显微镜下观察CM-DiI标记细胞的分布,并测量各组内膜损伤血管再生内皮覆盖率和新生内膜增生程度。结果荧光显微镜下发现荧光标记的内皮祖细胞分布在血管的中膜层、新生内膜层和内膜表面。内皮祖细胞移植可显著促进内膜损伤血管的再内皮化,以高细胞数量移植组为著,同时内皮祖细胞移植也大大减少了新生内膜的形成。结论内皮祖细胞移植可修复内膜球囊损伤血管,高细胞数量移植有更显著的效果。

Ahn To investigate the impact by delivery of different number of endothelial progenitor cells （EPC） on repair of injured vessels. Methods Mononuclear cells （MNC） were isolated from rabbit peripheral blood by density-gradient centrifugation. MNC were cultured in endothelial growth medium for 7 days, yielding EPC. Autologous EPC （5 × 10^5 cells or 2 × 10^5 calls in 100 μL saline） or 100 μL saline alone （control） were administered into a rabbit model of balloon carotid injury. Meanwhile the cells were labeled by CM-DiⅠ for cells tracking. Four weeks after transplantation, rabbits were killed. Fluorescence-labeled EPC, endothelial regeneration rate and interal area/media area （IA/MA）ratio were detected weeks after transplantation, fluorescence-labeled EPC were detected within the media, neointima and on the luminal surface of injured vessel. Local transplantation of EPC compared with saline administration markedly accelerated endothelialization of denuded vessel, especially in the group of 5 × 10^5 EPC. Meanwhile EPC treatment significantly reduced neointimal formation. Conclusions Delivery of EPC to balloon-injured arteries is associated with accelerated reendothelialization and reduced neointimal formarion. More notable effect may turn out when larger number of EPC are delivelrl.