Research on the effect and mechanism of the CXCR-4-overexpressing BMSCs combined with SDF-1α for the cure of acute SCI in rats.

OBJECTIVE To evaluate the effect and mechanism of bone marrow stem cells (BMSCs) modified with CXCR-4 gene combined with stromal derived factor-1α (SDF-1α) in the treatment of acute spinal cord injury (SCI) in rats. MATERIALS AND METHODS CXCR-4 gene was transfected by a virus. Spinal cord injury rats were randomly divided into four groups: control group, SDF-1α group, CXCR-4/BMSC group and combined group. The motor function was evaluated with Blood Brain Barrier (BBB) score and the RNA expression of CXCR-4 were measured by PCR. Apoptosis of spinal cord was measured by TUNEL kit (Hu Bei, China). The protein level of Bcl-2 and Bax were measured by Western-blot. The BBB scores, mRNA CXCR-4 expression, and apoptosis rate were compared between four groups at 1d, 3d, 7d, 14d, 21d after the operation. RESULTS The exercise ability in combined group restored in early and late periods of SCI. The apoptosis rates in the combined group are less than other three groups; the difference was statistically significant (p < 0.05). Bcl-2 in combined group is higher than the other 3 groups and Bax is less than the other 3 groups, the difference is statistically significant (p < 0.05). CONCLUSIONS The neurological function of rats with a spinal cord can be improved by BMSCs modified with CXCR-4 combined with SDF-1α. The main mechanism may improve the expression of SDF-1α and decrease the apoptosis of the spinal cord.