脊髓全横断损伤激活的nestin+细胞迁移和分化的调控机制研究

脊髓全横断损伤后内源nestin+细胞会响应损伤而大量激活。最近的研究表明这些损伤激活的nestin+细胞具有神经干细胞特性，会向损伤区迁移并分化为神经元。但是，调控其迁移及分化的相关机制目前却并不清楚。因此，本项目拟构建Nestin-CreERT2-tdTomato谱系示踪小鼠脊髓全横断损伤模型并分离正常脊髓及损伤后不同天数损伤区附近脊髓内的nestin+细胞。借助单细胞测序技术，比较上述nestin+细胞之间的转录组信息，挖掘其向损伤区迁移和向神经元分化的可能调控机制，并通过体外细胞试验和体内脊髓全横断损伤模型对上述候选机制进行验证。最终针对关键调控机制设计和制备功能支架材料，并评估功能支架材料移植对脊髓全横断损伤动物神经桥接网络重建及肢体感觉运动功能修复的治疗效果。本项目的顺利实施将可为利用损伤激活的nestin+细胞来修复脊髓全横断损伤提供理论依据和干预指导。

Complete transected spinal cord injury (SCI) induces massive activation of endogenous nestin+ cells. Recent studies have shown that some of the activated nestin+ cells could migrate into the lesion site and exhibit neural stem cell (NSC) potential to differentiate into neurons, while the intrinsic regulatory mechanisms are not clear. This project intends to construct Nestin-CreERT2-tdTomato mouse system for genetic fate mapping of the activated nestin+ cells post complete transected SCI. Nestin+ cells in uninjured cord as well as activated at different days after SCI will be isolated and single-cell sequencing will be utilized to compare their transcriptome information to reveal the relevant migration and differentiation regulatory mechanisms. Then, the candidate genes and/or signal pathways involving in the above mechanisms will be validated by NSCs culture system in vitro and complete transected SCI model in vivo. Finally, functional scaffold specifically intervening the key mechanisms will be developed and the therapeutic effect on promoting neural bridging networks reconstruction and sensory and motor function regeneration will be evaluated. The successful implementation of this project will provide theoretical basis and intervention guidance for complete SCI repair by using injury-activated nestin+ cells.