XCR4基因修饰骨髓间充质干细胞体外迁移实验

he aim of this study is to construct CXCR4 gene modified bone marrow mesenchymal stem cells (MSCs), and investigate the effect of CXCR4 expression on MSCs migration. S-D rat MSCs were isolated and expanded. The retrovirus vector pMSCV-CXCR4-IRES-GFP that expresses human CXCR4 gene was cloned, and was used to generate CXCR4 retroviral particles with 293T packaging cell line. MSCs was infected by the virus, and the expression of CXCR4 was analyzed by FACS, RT-PCR and immunofluorescence staining. The migration assay was performed using Transwell in the presence of SDF-1. FACS results show that 46% of the infected MSCs were CXCR4 positive, and 57% were GFP positive. The expression of CXCR4 in MSCs was also confirmed by RT-PCR and immunostaining. The migration of MSCs was induced by SDF-1 and strongly dependent on CXCR4 expression. The transmigration rate of CXCR4 modified MSCs was 15 folds higher than that of un-modified MSCs. The concentration of SDF-1 also has effect on the migration. The optimal concentration was found to be 50 ng/mL. These data indicate that SDF-1/CXCR4 plays important role in MSCs migration. The CXCR4 genetic modification approach could be applied to enhance cell homing and engraftment in MSCs therapy.