血管内皮生长因子通过CXCR4增强间充质干细胞的趋化能力

Vascular endothelial growth factor enhances chemotactic activity of mesenchymal stem cells through promoting CXCR4 expression

目的探索血管内皮生长因子能否通过促进间充质干细胞高表达CXCR4而增加其趋化能力。方法体外培养间充质干细胞铺满约90%时,给与血管内皮生长因子刺激,然后在不同的时间点,用流式细胞术检测间充质干细胞胞内表达CXCR4的变化。CM-DiI标记预先经过及未经过血管内皮生长因子处理的间充质干细胞,通过尾静脉注射到肝损伤小鼠体内,并通过CM-DiI的荧光强度比较来明确趋化到肝脏的间充质干细胞数量的差异。结果经过血管内皮生长因子刺激后,原来低表达CXCR4的间充质干细胞高表达CXCR4。而且在6小时的时间点,CXCR4表达量最高。经刺激后高表达CXCR4的间充质干细胞趋化能力得到提高。结论血管内皮生长因子上调CXCR4的表达,增强间充质干细胞的归巢及趋化能力。

Objective To investigate the effect of vascular endothelial growth factor （VEGF） on CXCR4 expression by mesenchymal stem cells （MSCs） in vitro. Methods CXCR4 expressed from MSCs was detected by flow cytometry. MSCs were stimulated by VEGF. At different time points, mesenchymal stem cells were collected, and then flow cytometry detected CXCR4 expression of MSCs. After cells were treated with VEGF, cells were stained with CM-DiI. These cells were transplanted into liver injuried mice through tail vein. Fluorescence of CM-DiI was detected by fluorescence microscope. Results VEGF could up-regulate CXCR4 expression by MSCs. And, after stimulation of VEGF on MSCs, MSCs increased chemotactic activity. Furthermore, inflammatory factor in serum from fulminant hepatic failur mice did not affect CXCR4 expression of MSCs. Conclusion VEGF up-regulates CXCR4 expression by MSCs. Increasing CXCR4 expression of MSCs by VEGF enhances MSCs chemotactic activity and homing ability.