Hejrati Nader, Lou Zijian, Kouhzaei Sogolie, Zhang Oliver, Wang Jian, Khazaei Mohamad, Fehlings Michael G
Division of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, ON M5T 0S8, Canada.
Department of Neurosurgery, HOCH health Ostschweiz, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
Stem Cells Transl Med. 2025 May 31;14(6). doi: 10.1093/stcltm/szaf014.
Spinal cord injury (SCI) elicits a hostile microenvironment characterized by inflammation, gliosis, and disrupted signaling pathways that collectively impede neural repair. Neural progenitor cells (NPCs) represent a promising regenerative approach, yet their survival and differentiation are often compromised in this setting. Here, we investigated whether engineering NPCs to overexpress the Notch pathway modulator Delta-like non-canonical Notch ligand 1 (DLK1) could overcome these limitations and improve functional outcomes after cervical SCI in rats. NPCs were engineered to express DLK1 under a Pax6 promoter-driven expression system, ensuring elevated DLK1 levels during the progenitor state. Following transplantation of DLK1-overexpressing NPCs or control NPCs, we assessed graft survival, lineage differentiation, behavioral performance, and electrophysiological integration over 12 weeks. DLK1-expressing NPCs exhibited significantly greater retention in the injured spinal cord and showed enhanced neuronal differentiation alongside reduced astrocytic commitment compared to controls. Behavioral tests-including forelimb grip strength and CatWalk gait assessments-demonstrated that DLK1-modified NPCs conferred robust improvements in forelimb motor coordination and overall locomotion. Concordantly, electrophysiological recordings revealed increased motor-evoked potential amplitudes and area-under-the-curve values in animals receiving DLK1-transduced NPC grafts, indicative of strengthened synaptic integration within the host motor circuitry.
脊髓损伤（SCI）会引发一个充满敌意的微环境，其特征为炎症、胶质增生以及信号通路紊乱，这些因素共同阻碍神经修复。神经祖细胞（NPCs）是一种很有前景的再生方法，然而在这种情况下它们的存活和分化常常受到影响。在此，我们研究了对NPCs进行工程改造使其过表达Notch信号通路调节剂类Delta非经典Notch配体1（DLK1）是否能够克服这些限制并改善大鼠颈段脊髓损伤后的功能结局。利用Pax6启动子驱动的表达系统对NPCs进行工程改造，使其表达DLK1，以确保在祖细胞状态期间DLK1水平升高。在移植过表达DLK1的NPCs或对照NPCs后，我们在12周内评估了移植物存活、谱系分化、行为表现和电生理整合情况。与对照组相比，表达DLK1的NPCs在损伤脊髓中的留存率显著更高，并且神经元分化增强，同时星形胶质细胞的分化减少。行为测试，包括前肢握力和CatWalk步态评估，表明经DLK1修饰的NPCs在前肢运动协调和整体运动能力方面有显著改善。与此一致，电生理记录显示，接受经DLK1转导的NPC移植物的动物的运动诱发电位幅度和曲线下面积值增加，这表明宿主运动回路内的突触整合得到加强。
