Department of Anatomy, Histology, and Embryology, Faculty of Medicine, University of Szeged, Szeged, Hungary.
Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria.
J Neurotrauma. 2019 Nov 1;36(21):2977-2990. doi: 10.1089/neu.2018.6332. Epub 2019 Jul 10.
Spinal cord contusion injury leads to severe loss of gray and white matter and subsequent deficit of motor and sensory functions below the lesion. In this study, we investigated whether application of murine clonal embryonic neuroectodermal stem cells can prevent the spinal cord secondary damage and induce functional recovery. Stem cells (NE-GFP-4C cell line) were grafted intraspinally or intravenously immediately or one week after thoracic spinal cord contusion injury. Control animals received cell culture medium or fibrin intraspinally one week after injury. Functional tests (Basso, Beattie, Bresnahan, CatWalk) and detailed morphological analysis were performed to evaluate the effects of grafted cells. Stem cells applied either locally or intravenously induced significantly improved functional recovery compared with their controls. Morphologically, stem cell grafting prevented the formation of secondary injury and promoted sparing of the gray and white matters. The transplanted cells integrated into the host tissue and differentiated into neurons, astrocytes, and oligodendrocytes. In intraspinally grafted animals, the corticospinal tract axons regenerated along the ventral border of the cavity and have grown several millimeters, even beyond the caudal end of the lesion. The extent of regeneration and functional improvement was inversely related to the amounts of chondroitin sulphate and ephrin-B2 molecules around the cavity and to the microglial and astrocytic reactions in the injured segment early after injury. The grafts produced glial cell derived neurotrophic factor, macrophage inflammatory protein-1a, interleukin (IL)-6 and IL-10 in a paracrine fashion for at least one week. Treating the grafted cords with neutralizing antibodies against these four factors through the use of osmotic pumps nearly completely abolished the effect of the graft. The non-significant functional improvement after function blocking is likely because the stem cell derivatives settled in the injured cord. These data suggest that grafted neuroectodermal stem cells are able to prevent the secondary spinal cord damage and induce significant regeneration via multiple mechanisms.
脊髓挫伤导致灰质和白质严重损失，并随后导致损伤以下的运动和感觉功能缺陷。在这项研究中，我们研究了应用鼠克隆胚胎神经外胚层干细胞是否能防止脊髓继发性损伤并诱导功能恢复。干细胞（NE-GFP-4C 细胞系）在胸段脊髓挫伤后立即或一周内通过椎管内或静脉内移植。对照动物在损伤后一周内通过椎管内或静脉内接受细胞培养液或纤维蛋白。通过功能测试（Basso、Beattie、Bresnahan、CatWalk）和详细的形态学分析来评估移植细胞的效果。与对照相比，局部或静脉内应用的干细胞显著改善了功能恢复。形态学上，干细胞移植防止了继发性损伤的形成，并促进了灰质和白质的保留。移植细胞整合到宿主组织中，并分化为神经元、星形胶质细胞和少突胶质细胞。在椎管内移植的动物中，皮质脊髓束轴突沿着腔的腹侧边界再生，并生长了几毫米，甚至超过损伤的尾端。再生和功能改善的程度与腔周围软骨素硫酸盐和 Ephrin-B2 分子的数量以及损伤段中小胶质细胞和星形胶质细胞的早期反应呈负相关。移植物以旁分泌的方式产生胶质细胞源性神经营养因子、巨噬细胞炎性蛋白-1a、白细胞介素 (IL)-6 和 IL-10，至少持续一周。通过使用渗透泵向移植的脊髓施用针对这四种因子的中和抗体，几乎完全消除了移植的效果。功能阻断后的非显著功能改善可能是因为干细胞衍生物在损伤的脊髓中定居。这些数据表明，移植的神经外胚层干细胞能够通过多种机制防止继发性脊髓损伤并诱导显著的再生。
