联合培养体系中对骨髓间充质干细胞Bmi-1表达的影响

Effects of co-culture system on Bmi-1 expression in bone marrow mesenchymal stem cells

背景:血管内皮细胞能够促进骨髓间充质干细胞向成骨方向转变,并为干细胞的生长增殖提供营养支持。目的:观察人脐静脉血管内皮细胞在联合培养体系中对人骨髓间充质干细胞的形态、生长、细胞分化及其Bmi-1基因表达的影响。方法:在建立细胞联合培养体系基础上,设立单纯骨髓间充质干细胞培养组、骨髓间充质干细胞与脐静脉血管内皮细胞联合培养组,分别于第4,6,8,10天在相差显微镜下观察形态变化、细胞计数绘制生长曲线并采用实时荧光定量PCR检测单独培养的人骨髓间充质干细胞组及联合培养组中人骨髓间充质干细胞的Bmi-1基因表达情况。结果与结论:在各时间点与单纯骨髓间充质干细胞培养组相比较,联合培养组中干细胞的形态呈多样化,后期部分细胞之间出现了连接,成骨分化明显。联合培养组的细胞数量以及Bmi-1表达量各时间点均显著高于单纯骨髓间充质干细胞培养组。联合培养相容性良好。提示脐静脉内皮细胞对体外联合培养体系中骨髓间充质干细胞具有促进增殖的作用;能促进骨髓间充质干细胞Bmi-1基因的表达,对细胞衰老和增殖能力有显著影响。

BACKGROUND：Vascular endothelial cells can promote osteogenic differentiation of bone marrow mesenchymal stem cells（BMSCs） and provide nutritional support for growth and proliferation of BMSCs.OBJECTIVE：To investigate the effects of human umbilical vein vascular endothelial cells（hUVECs） in a co-culture system on morphology,growth and differentiation of human BMSCs,and Bmi-1 gene expression in cells.METHODS：Based on the co-culture system of cells,a simple culture group（hBMSCs group） and a combined culture group（BMSCs ＋ hUVECs group） were established.On days 4,6,8,10,cell morphology was observed and cells were counted for drawing cell growth curves;in addition,Bmi-1 gene expression in cells was detected in each group using real-time quantitative fluorescent PCR.RESULTS AND CONCLUSION：At each time point,compared with hBMSCs group,cells exhibited multiple morphological changes,some cells connected together in the latter stage,and osteogenic differentiation was more obvious in the BMSCs ＋ hUVECs group.At each time point,cell number and Bmi-1 expression in the BMSCs ＋ hUVECs group were significantly greater than in the BMSCs group.The BMSCs ＋ hUVECs group showed a better compatibility compared with the hBMSCs group.These findings suggest that hUVECs promote the proliferation of hBMSCs in the co-culture system,and increase Bmi-1 expression in hBMSCs,thereby affecting aging and proliferative capacity of hBMSCs.