大鼠骨髓间充质干细胞体外向血管平滑肌样细胞的诱导分化

In vitro differentiation of rat bone marrow mesenchymal stem cells into vascular smooth muscle cell-like cells

背景:有研究表明,血管外膜成纤维细胞被激活早期参与动脉粥样硬化及血管再狭窄的形成,另有研究表明,骨髓间充质干细胞有部分黏附分化参与血管重塑,实验拟从血管外膜成纤维细胞与骨髓间充质干细胞之间相互作用的角度,来探讨动脉硬化及血管损伤后再狭窄过程中的可能机制。目的:观察骨髓间充质干细胞与血管外膜成纤维细胞直接接触培养后,骨髓间充质干细胞形态改变及表达血管平滑肌肌动蛋白的情况。方法:将骨髓间充质干细胞(DAPI标记细胞核)与外膜成纤维细胞按一定的比例混合培养7d,细胞单独培养作对照,显微镜下观察细胞形态变化,免疫荧光检测骨髓间充质干细胞平滑肌肌动蛋白表达的情况。结果与结论:骨髓间充质干细胞与血管外膜成纤维细胞共培养后,可见骨髓间充质干细胞的细胞核蓝染(DAPI标记细胞核)、胞浆红染(平滑肌肌动蛋白阳性)的双标细胞出现,且随培养时间的延长,骨髓间充质干细胞的平滑肌肌动蛋白表达阳性率明显增高。结果可见与血管外膜成纤维细胞直接接触有诱导骨髓间充质干细胞向血管平滑肌样细胞分化的趋势。

BACKGROUND： Studies have shown that the early activated adventitial fibroblasts cells are involved in the atherosclerosis and in the formation of vascular restenosis, and other studies have shown that some bone marrow mesenchymal stem cells are adherent, differentiate and participate in vascular remodeling. The experiment was to explore the possible mechanism of bone marrow mesenchymal stem cells involved in the atherosclerosis and the formation of vascular restenosis through analyzing the interaction between adventitial fibroblasts and bone marrow mesenchymal stem cells. OBJECTIVE： To observe the morphological changes of bone marrow mesenchymal stem cells and the expression of vascular smooth muscle actin after bone marrow mesenchymal stem cells directly contactedwith adventitial fibroblasts. METHODS： Rat bone marrow msenchymal stem cells （DAPI-labeled nucleus） and adventitial fibroblasts were mixed and co-cultured for 7 days. Bone marrow mesenchymal stem cells were cultured alone as controls. The morphological changes of co-cultured cells were observed. The expression of vascular smooth muscle actin was detected with immunofluorescence staining. RESULTS AND CONCLUSION： After co-cultured with adventitial fibroblasts, bone marrow mesenchymal stem cells exhibited DAPI-labeled blue nuclei and red stained cytoplasm （positive smooth muscle actin）. With the prolongation of culture time, smooth muscle actin expression in the bone marrow mesenchymal stem cells was significantly increased. These results indicate that bone marrow mesenchymal stem cells can differentiate into vascular smooth muscle cell-like cells after directly contacting with adventitial fibroblasts.