Patar Azim, Dockery Peter, McMahon Siobhan, Howard Linda
Discipline of Anatomy, College of Medicine Nursing and Health Sciences, National University of Ireland Galway, H91 YR71 Galway, Ireland.
Department of Neuroscience, School of Medical Sciences, Universiti Sains Malaysia, Gelugor 11800, Malaysia.
Biology (Basel). 2020 Mar 15;9(3):54. doi: 10.3390/biology9030054.
The failure of the spinal cord to regenerate can be attributed both to a lack of trophic support for regenerating axons and to upregulation of inhibitory factors such as chondroitin sulphate proteoglycans including NG2 following injury. Lentiviral vector-mediated gene therapy is a possible strategy for treating spinal cord injury (SCI). This study investigated the effect of lentiviral vectors expressing Neurotrophin-3 (NT-3) and short-hairpin RNA against NG2 (NG2 sh) to enhance neurite outgrowth in in vitro and ex vivo transection injury models. Conditioned medium from cells transduced with NT-3 or shNG2 lentiviruses caused a significant increase in neurite length of primary dorsal root ganglia neurons compared to the control group in vitro. In an ex vivo organotypic slice culture (OSC) transduction with Lenti-NT-3 promoted axonal growth. Transducing OSCs with a combination of Lenti-NT-3/NG2 sh lead to a further increase in axonal growth but only in injured slices and only within the region adjacent to the site of injury. These findings suggest that the combination of lentiviral NT-3 and NG2 sh reduced NG2 levels and provided a more favourable microenvironment for neuronal regeneration after SCI. This study also shows that OSCs may be a useful platform for studying glial scarring and potential SCI treatments.
脊髓无法再生既可以归因于对再生轴突缺乏营养支持，也可以归因于损伤后诸如硫酸软骨素蛋白聚糖（包括NG2）等抑制因子的上调。慢病毒载体介导的基因治疗是治疗脊髓损伤（SCI）的一种可能策略。本研究调查了表达神经营养因子-3（NT-3）的慢病毒载体和针对NG2的短发夹RNA（NG2 sh）在体外和离体横断损伤模型中对促进神经突生长的作用。与对照组相比，用NT-3或shNG2慢病毒转导的细胞的条件培养基在体外使初级背根神经节神经元的神经突长度显著增加。在离体器官型切片培养（OSC）中，用Lenti-NT-3转导可促进轴突生长。用Lenti-NT-3/NG2 sh组合转导OSC可导致轴突生长进一步增加，但仅在损伤切片中且仅在损伤部位附近区域。这些发现表明，慢病毒NT-3和NG2 sh的组合降低了NG2水平，并为SCI后神经元再生提供了更有利的微环境。本研究还表明，OSC可能是研究胶质瘢痕形成和潜在SCI治疗方法的有用平台。
