静脉移植CXCR-4基因转染骨髓间充质干细胞在脊髓损伤鼠体内的迁移与分化

背景：研究发现,基质细胞衍生因子1/CXCR-4轴具有介导骨髓间充质干细胞定向迁移的作用。 目的：观察静脉移植CXCR-4基因转染间充质干细胞治疗脊髓损伤的可行性。 方法：利用脊髓横切法构建C57BL/6小鼠T10脊髓损伤模型,造模后7 d抽签随机分成3组：实验组经尾静脉注射CXCR-4基因转染同种异体骨髓间充质干细胞悬液,对照组与空白对照组分别注射同种异体骨髓间充质干细胞悬液及无细胞培养基。移植后第7,14,21,28天利用激光共聚焦显微镜、免疫组织化学双标染色法检测脊髓损伤部位绿色荧光蛋白阳性细胞迁移存活及分化情况,并采用BBB评分评估小鼠神经运动功能恢复情况。 结果与结论：实验组移植后各时相点损伤灶内绿色荧光蛋白阳性细胞集聚明显,数量不断增多,迁移率明显高于对照组与空白对照组,来源于骨髓间充质干细胞的神经细胞占移植细胞的比例亦高于对照组与空白对照组,小鼠神经运动功能恢复明显。说明静脉移植CXCR-4基因转染的骨髓间充质干细胞表现出对脊髓损伤灶更强的定向迁移能力,且能在损伤灶内存活、分化,发挥修复损伤脊髓作用。

Immigration and differentiation of bone marrow mesenchymal stem cells transfected by CXCR-4 gene after intravenous transplantation in mice with spinal cord injury

BACKGROUND:Previous studies demonstrated that stromal cell derived factor-1/CXCR-4 axis system plays a role in mediating bone marrow mesenchymal stem cells’ (BMSCs) orient immigration. OBJECTIVE:To investigate the feasibility of BMSCs transfected by CXCR-4 gene after intravenous transplantation for treatment of spinal cord injury (SCI). METHODS:C57BL/6 mice T10 SCI model was constructed by spinal cord transection method, and at 7 days after modeling, which were randomly divided into 3 groups: experimental group, control group and blank group. Mice were intravenous injected by the suspensions of allogeneic BMSCs transfected by CXCR-4 gene in experimental group. Mice were respectively intravenous injected by the suspensions of non-transfected allogeneic BMSCs and non-cell culture medium in control and blank groups. At 7, 14, 21, 28 days after transplantation, the survival and differentiation of green fluorescence protein positive cells to all cells in different site after transplantation were detected by laser scanning confocal microscope and Immunohistochemical double staining method. BBB score was used to evaluate the recovery condition of neuromotor function of mice. RESULTS AND CONCLUSION:After transplantation, green fluorescence protein positive cells significantly gathered in the injured part of spinal cord in experimental group at each time point, and the number gradually increased, and the transport factor was obviously higher than in control and blank groups. The proportion of neural cells from BMSCs in transplanted cells in experimental group was also higher than that in control and blank groups. The neuromotor function of mice recovered obviously. BMSCs transfected by CXCR-4 gene after intravenous transplantation showed stronger orient immigration ability to SCI focus, which can survive and differentiate in the SCI focus, and play a role in repairing SCI.