Snail基因修饰对骨髓间充质干细胞CXCR4表达水平及向SDF-1趋化能力的影响

Effects of Snail gene modification on CXCR4 expression of human bone mesenchymal stem cells and their capacity of migration to SDF-1 in vitro

为研究Snail基因修饰对骨髓间充质干细胞(MSCs)CXCR4表达水平及向SDF-1趋化能力影响,将重组真核表达载体(pCAGGSneo-snail-HA)及对照空质粒(pCAGGSneo)转染MSCs,采用免疫荧光细胞化学染色、荧光标记流式细胞仪技术及RT-PCR检测细胞CXCR4表达水平;体外跨膜趋化实验评价MSCs向SDF-1趋化能力,观察抗CXCR4中和抗体的干预作用。MSCs-Sna的CXCR4表达水平明显高于MSCs-neo。MSCs-Sna在SDF-1诱导下细胞迁移量较MSCs-neo显著增加(P<0.05)。抗CXCR4中和抗体可显著减少SDF-1α诱导的MSCs-Sna趋化运动。研究提示通过上调Snail表达而提高MSCs向正调节表达SDF-1的受损组织迁移效率的可行性,为优化MSCs迁移力的研究提供了实验基础。

In order to investigate the transfer and expression of Snail gene in human bone mesenchymal stem cells （MSCs） and to study effects of Snail gene modification on the CXCR4 expression of human MSCs and their capacity of migration to SDF- 1 in vitro, the plasmid PCAGGSneo-Snail-HA or the control vector of PCAGGSneo was transferred into the cells. Fluorescence activated cell sorting analysis, immunofluorescence staining and RT-PCR were used to study the expression of CXCR4 by MSCs. Chemotaxis assays were performed to evaluate the migratory capacity of MSCs-Sna and MSCs-neo to SDF-1 in vitro. For the blocking assay,CXCR4 blocking antibody was added into cell culture. CXCR4 expression was higher in MSCs-Sna than that in MSCs-neo （P〈0.05）. Chemotaxis assays showed that SDF-1α stimulated migratory activity of MSCs-Sna more than MSCs-neo in vitro （P〈0.05）. Moreover, the SDF-1α-induced migratory activity of MSCs-Sna was inhibited in a concentration-dependent manner by a CXCR4-blocking antibody. It was concluded that Snail enhanced expression of CXCR4 in MSCs, providing a plausible mechanism for Snail-mediated MSCs transmigration to damaged tissues in vivo where SDF-1 has been shown to be up-regulated as part of injury responses.