水凝胶携带NgR1沉默的神经干细胞移植治疗脊髓损伤的研究

神经干细胞（NSC）移植是治疗脊髓损伤具有应用前景的手段之一，然而尚需克服移植后有限的神经元分化率问题。基于脊髓损伤后释放的髓磷脂相关抑制因子与其受体NgR1参与NSC分化过程的调控，两者的相互作用介导NSC向星形胶质细胞分化；同时课题组前期工作表明水凝胶具有良好生物相容性，可作为NSC体内移植的载体，本研究拟利用RNAi沉默NSC的NgR1表达，诱导NSC向神经元定向分化，并以水凝胶搭载NSC移植体内，实现细胞的有效局部递送，治疗大鼠脊髓损伤。以免疫荧光、BDA示踪、电镜等检测移植后NSC的分化及大鼠神经轴突再生、髓鞘形成等情况，Western blot检测神经再生、外基质重建、炎症因子及凋亡相关蛋白的水平变化，结合运动功能与电生理评价，阐明NgR1沉默对移植体内后的NSC分化的影响，以及该治疗对脊髓损伤大鼠神经再生、运动功能恢复的作用和机制，有望为今后脊髓损伤的治疗提供新的思路。

Neural stem cells (NSC) transplantation is one of the prospective treatments for spinal cord injury. However, a major barrier need to be overcome: limited rate of neuronal differentiation. Recent studies indicated that myelin associated inhibitory factors and their common receptor NgR1 participate in the differentiation process of NSC. Their interaction mediated NSC differentiated into astrocytes. And Our previous work has shown that hydrogel was biocompatible and could be used as a carrier in NSC transplantation. This study intends to test the effects of NgR1 gene silencing NSC delivered by hydrogel on the treatment of spinal cord injury in rats. Immunofluorescence, BDA tracing and electron microscopy are untilized to detecte NSC differentiation after transplantation, axonal regeneration and myelination in rats. Western blot detects the levels of proteins that reflecting nerve regeneration, extracellular matrix reconstruction, inflammatory and apoptosis. Motor functional and electrophysiological recovery is determined by BBB scoring and evoked potentials. Our study aims to clarify the role and mechanism of NgR1 silencing in the differentiation of transplanted NSC, as well as the therapeutic effects on nerve regeneration and functional recovery in spinal cord injury rat. And our work is expected to provide new ideas and methods for the treatment of spinal cord injury in the future.