脊髓损伤以其高致残率和死亡率给社会和家庭带来沉重负担。研究表明损伤处轴突再生抑制和突触丧失是脊髓损伤后结构重建和功能康复的一个难题。尽管骨髓间充质干细胞（BMSCs）移植治疗脊髓损伤有积极效果，但其在轴突再生和突触重建方面仍不令人满意。结合参考文献和我们的前期研究，发现血小板反应素1（TSP-1）能通过TGF-β1促进突触形成，同时对轴突生长抑制通路相关蛋白RhoA有显著抑制作用。为此本研究拟采用TSP-1及其小干扰RNA分别修饰BMSCs，通过上调和降低TSP-1表达，观察修饰后BMSCs的生物学性状，随后移植治疗大鼠脊髓损伤和体外神经元损伤模型，观察其轴突再生、突触重建、脊髓运动诱发电位和运动功能康复情况，并检测移植后不同时间段TSP-l/TGF-β1和RhoA通路相关蛋白表达。本研究可初步阐明TSP-1修饰的BMSCs促进脊髓损伤再生修复的相关作用机制，为脊髓损伤治疗提供新的策略。

Spinal cord injury is extremely serious trauma and caused a heavy burden on society and family. The study shows that the loss of synapse and axon regeneration inhibition were the key challenge of functional recovery after spinal cord injury. Although bone marrow mesenchymal stem cells (BMSCs) transplantation was effective for treatment of SCI, it was still not satisfactory in axonal regeneration and synaptic remodeling. Our previous study and other researchers found that the thrombospondin 1 (TSP-1) can promote synapse formation and down-regulat the axon growth inhibitory pathway protein-RhoA activity. The present study intends to modify TSP-1 gene and TSP-1 small interfering RNA on BMSCs to up or down regulate the TSP-1 expression, and observe the biological function of BMSCs after its modification. We will exam the TSP-l/TGF-β1 and RhoA pathway-associated protein expression, axonal regeneration and synaptic reconstruction, spinal cord motor evoked potentials and motor function after transplantation these modified BMSCs to in vitro and in vivo spinal cord injury model. The present study would clarify the proper mechanism of TSP-1 modified BMSCs in rehabilitation after spinal cord injury, and provide a new strategy for the treatment of spinal cord injury.