Brain Pathol|Nikolaos Grigoriadis团队指出NPC腰椎鞘内移植可促进少突胶质细胞增殖

2022年8月4日 0条评论 238次阅读 0人点赞

最新细胞功能及机制文献分享

实验性自身免疫性脑脊髓炎（EAE）是一种用于研究啮齿类动物多发性硬化症（MS）临床和病理特征的基本且可靠的模型。有研究表明，神经前体细胞（NPC）是一种重要的研究工具，移植的NPC是治疗神经系统疾病的一种很有前景的治疗方法。2021年11月29日，希腊塞萨洛尼基AHEPA大学医院神经病学第二科实验神经病学和神经免疫学实验室Nikolaos Grigoriadis团队在Brain Pathology上发表了题为“Lumbar spine intrathecal transplantation of neural precursor cells promotes oligodendrocyte proliferation in hot spots of chronic demyelination”的研究论文。在本研究中，团队的主要目标是通过腰椎穿刺方法，针对EAE主要慢性脱髓鞘腰骶部环境，研究NPC少突胶质细胞生成的临床前与体内场景。建议单次腰椎鞘内注射NPCs可改善细胞负荷获得能力，刺激少突胶质前体细胞（OPCs），克服EAE脱髓鞘部位的髓鞘再生失败的临床和病理特征。这是第一项描述NPC在宿主少突发育中的作用和脱髓鞘环境中少突胶质细胞增殖的研究。

临床数据表明，多发性硬化症（MS）患者大脑内的内源性细胞对慢性病变的修复能力有限，现有少突胶质细胞对轴突髓鞘再生不可避免地会出现实质性失败。在这种情况下，NPC移植可提供重要的优势，其不仅可通过炎症期间的免疫调节作用控制免疫反应，还可通过与宿主组织的化学偶联作用为机体提供营养支持。在此项研究中，团队利用腰椎穿刺技术研究了慢性炎症性脱髓鞘的原位效应以及细胞的病理性驱动迁移和分化，同时量化局部OPCs产生的长期后遗症、增殖以及对髓鞘再生过程能力的调节作用。具体如下，利用MOG_35-55肽在C57BL/6小鼠中诱导EAE，在急性复发之前，于腰椎鞘内注射可追踪的GFP⁺细胞。之后体内注射BrdU，监测细胞内源性增殖，结合高通量测序技术、三重免疫荧光和透射电子显微镜（TEM）数据进行神经病理学检测。

结果发现，在急性临床复发后，NPC移植可显著缓解EAE慢性期，并且，NPCs有助于改善模型小鼠的脱髓鞘、轴突丢失和免疫相关细胞群。值得注意的是，移植小鼠的炎症区域与GFP⁺细胞的位置相关，显示出下降趋势，尤其是在较低的白质束中，即外源性NPC表现出潜在免疫调节作用，与保护髓鞘和轴突完整性有关；不仅如此，团队在长达50多天的观察中发现，移植的NPCs在诱导后50天（50dpi）仍能存活，并在受损CNS环境中有效迁移。机制上，NPCs可获得少突胶质细胞谱系特征并进一步参与宿主组织少突胶质细胞的富集，BCAS1和Olig2亚群通过少突胶质细胞连接蛋白表现出直接相互作用，从而增强了宿主髓鞘形成。

《Brain Pathol|Nikolaos Grigoriadis团队指出NPC腰椎鞘内移植可促进少突胶质细胞增殖》

图 EAE组腰椎鞘内注射和临床过程示意图。

期刊及DOI号

Brain Pathol. 2021 Nov 29.

doi: 10.1111/bpa.13040.

题目

Lumbar spine intrathecal transplantation of neural precursor cells promotes oligodendrocyte proliferation in hot spots of chronic demyelination

摘要

Experimental autoimmune encephalomyelitis (EAE) is a basic and reliable model used to study clinical and pathological hallmarks of multiple sclerosis (MS) in rodents. Several studies suggest neural precursor cells (NPCs) as a significant research tool while reporting that transplanted NPCs are a promising therapeutic approach to treating neurological disorders, such as MS. The main objective was to approach a preclinical, in vivo scenario of oligodendrogenesis with NPCs, targeting the main chronic demyelinated lumbosacral milieu of EAE, via the least invasive delivery method which is lumbar puncture. We utilized MOG_35-55 peptide to induce EAE in C57BL/6 mice and prior to the acute relapse, we intervened with either the traceable GFP⁺ cellular therapy or saline solution in the intrathecal space of their lumbar spine. A BrdU injection, which enabled us to monitor endogenous proliferation, marked the endpoint 50 days post-induction (50 dpi). Neuropathology with high-throughput, triple immunofluorescent, and transmission electron microscopy (TEM) data were extracted and analyzed. The experimental treatment attenuated the chronic phase of EAE (50 dpi; score <1) following an acute, clinical relapse. Myelination and axonal integrity were rescued in the NPC-treated animals along with suppressed immune populations. The differentiation profile of the exogenous NPCs and endogenous BrdU⁺ cells was location-dependent where GFP⁺-rich areas drove undifferentiated phenotypes toward the oligodendrocyte lineage. In situ oligodendrocyte enrichment was demonstrated through increased (p<0.001) gap junction channels of Cx32 and Cx47, reliable markers for proliferative oligodendroglia syncytium. TEM morphometric analysis ultimately manifested an increased g-ratio in lumbosacral fibers of the recovered animals (p<0.001). Herein, we suggest that a single, lumbar intrathecal administration of NPCs capacitated a viable cellular load and resulted in clinical and pathological amelioration, stimulating resident OPCs to overcome the remyelination failure in EAE demyelinating locale.