IMMUNOPATHOGENESIS OF VIRUS-INDUCED DEMYELINATION

嗜神经性冠状病毒感染C57B1/6(B6)小鼠 肝炎病毒株JHM发展为脱髓鞘脑脊髓炎 后肢瘫痪的临床症状。多发性骨髓瘤的临床和病理特点 这种疾病与人类的多发性硬化症有许多相似之处。 MS和感染MHV的小鼠的一个重要相似之处是，宿主 免疫反应对脱髓鞘的发生发展起关键作用。申请人 最近有研究表明，MHV感染缺乏成熟T和B细胞的小鼠 由于重组酶激活基因活性不足(Rag1-/-小鼠) 不会发生脱髓鞘，除非来自免疫活性B6的脾细胞 收养转移。然后，脱髓鞘可在6-7天内重复发生。在……里面 此外，他还改进了识别抗原特异性CD4和CD8T的方法 细胞(可溶性MHC/肽四聚体分析法和测定用分析法 细胞内干扰素-γ的产生)，以直接进行体外分析 从MHV诱导的神经系统疾病小鼠身上获得的淋巴细胞。 这项提议的中心假设是，过继转移的CD4或 CD8 T细胞分泌一种关键因子或执行一种功能(或两者兼而有之) 在RAG-/-中诱导和/或传播脱髓鞘过程 老鼠。这一假设将在以下三个具体目标中得到实现。 1.确定抗原特异性的CD4或CD8 T细胞是否在缺乏 其他亚群足以诱导和传播脱髓鞘过程。 Fas/FasL相互作用及特异性趋化因子和 细胞因子也将被确定。2.研究一氧化氮的作用 和轴突变性，这是致病的两个潜在关键成分 过程中，在采用转移模型的脱髓鞘。3.确定 MHV抗原非特异性CD4T细胞是否被激活并参与 病毒感染的小鼠脱髓鞘。这些实验将利用 我们检测抗原特异性CD4T细胞能力的最新进展 感染MHV的中枢神经系统。 经过继转移到MHV感染者体内后，脱髓鞘迅速且可重现 Rag1-/-小鼠，使这一独特的系统研究的发病机制 病毒诱导的脱髓鞘和回答有关病毒诱导的脱髓鞘的问题。

C57B1/6 (B6) mice infected with the neurotropic coronavirus, mouse hepatitis virus, strain JHM, develop a demyelinating encephalomyelitis with clinical signs of hindlimb paralysis. The clinical and pathological features of this disease have many similarities to the human disease, multiple sclerosis. One important similarity between MS and the MHV-infected mouse is that the host immune response is critical for the development of demyelination. The applicant has recently shown that MHV infection of mice that lack mature T and B cells due to a deficiency in recombinase-activating gene activity (Rag1 -/- mice) do not develop demyelination unless splenocytes from immunocompetent B6 are adoptively transferred. Demyelination then occurs reproducibly in 6-7 days. In addition, he has adapted methods for identifying antigen-specific CD4 and CD8 T cells (soluble MHC/peptide tetramer assays and assays for measuring intracellular interferon-gamma production) to the direct ex vivo analysis of lymphocyte harvested from mice with MHV-induced neurological disease. The central hypothesis of this proposal is that adoptively transferred CD4 or CD8 T cells secrete a factor or perform a function (or both) that is critical for the induction and/or propagation of the demyelinating process in Rag -/- mice. This hypothesis will be approached in the following three specific aims. 1. To determine if antigen-specific CD4 or CD8 T cells in the absence of the other subset are sufficient to induce and propagate the demyelinating process. The contribution of Fas/FasL interactions and of specific chemokines and cytokines will also be determined. 2. To investigate the role of nitric oxide and axonal degeneration, two potentially key components of the pathogenic process, in the adoptive transfer model of demyelination. 3. To determine whether MHV antigen-nonspecific CD4 T cells become activated and contribute to demyelination in virus-infected mice. These experiments will take advantage of recent advances in our ability to detect antigen-specific CD4 T cells in the MHV-infected CNS. Demyelination is rapid and reproducible after adoptive transfer into the MHV-infected Rag1 -/- mice, making this a unique system for investigating the pathogenesis of virus-induced demyelination and answering questions about virus-induced demyelination.