Immune Regulation of Neuronal Injury and Repair

描述（由申请人提供）：我们已经建立了涉及轴突切断野生型（WT）小鼠面部运动神经元（FMN）的CD 4 + T细胞介导的神经保护的生理学相关机制，其可能在肌萎缩侧索硬化症（ALS）（一种致死性运动神经元疾病）的治疗中具有重要意义。叠加面神经轴突切断术（FNA）的转基因小鼠模型的ALS（SOD 1G 93 A）在症状前阶段表明，SOD 1小鼠的行为像免疫缺陷（ID）小鼠方面增加FMN损失和减少功能恢复，通过一种机制，矛盾的是，不是内在的运动神经元本身，而是，涉及外周免疫缺陷：中枢神经系统胶质细胞的相互作用。该项目的长期目标是利用FNA后免疫介导的神经保护的WT小鼠模型作为模板，以阐明外周免疫系统故障如何导致ALS的SOD 1小鼠模型中运动神经元细胞损失。我们的中心假设是，CD 4+效应T细胞通过调节中枢小胶质细胞和星形胶质细胞对周围神经损伤的反应，为运动神经元提供神经保护。有4个具体目标，旨在：1）阐明FNA后WT面神经核中IL-10的功能作用，2）确定CD 4 + T细胞是否通过激活面神经核内的IL-10级联来拯救RAG-2 KO小鼠中FMN免于FNA诱导的细胞死亡，3）确定在症状前SOD 1小鼠中FNA后阻止CD 4 +T细胞介导的神经保护的机制，和4）测试体外产生的神经保护性SOD 1 CD 4 + T细胞改变SOD 1小鼠中疾病发作和/或进展的能力。将使用IL-10报告基因和条件性IL-10敲除小鼠，沿着WT、ID和SOD 1小鼠的过继转移实验，以及激光捕获显微切割。基于本次修订产生的新数据，表明SOD 1 T细胞是正常的，但抗原呈递细胞（APC）是有缺陷的，将在体外使用相关和不相关抗原以及在体内使用过继转移检查SOD 1 T细胞和APC的表型和功能。最后，在疾病发作之前，将使用神经保护性FNA特异性T细胞或APC对SOD 1小鼠进行过继免疫治疗，并评估对疾病发作、进展和寿命的影响。关于预期的结果，这项工作预计将确定FNA后CD 4 + T介导的神经保护的关键机制要素，揭示ALS的SOD 1小鼠模型中FNA后的外周免疫系统缺陷，这些缺陷阻止有效的CD 4 + T细胞活化/分化，并确定过继免疫疗法的治疗潜力，该过继免疫疗法具有FNA抗原体外产生的神经保护性SOD 1 T细胞。ALS每年袭击30，000名美国人（每天15例），通常是在他们生活中的高峰生产点，并为受影响的个人，他们的家庭和医疗保健系统带来巨大的成本。识别神经：免疫相互作用中的缺陷将产生重要的积极影响，因为它们可以成为ALS治疗中治疗干预的目标。

DESCRIPTION (provided by applicant): We have established a physiologically relevant mechanism of CD4+ T cell-mediated neuroprotection involving axotomized wildtype (WT) mouse facial motoneurons (FMN) that may have significance in the treatment of amyotrophic lateral sclerosis (ALS), a fatal motoneuron disease. Superimposition of facial nerve axotomy (FNA) on the transgenic mouse model of ALS (SOD1G93A) during pre-symptomatic stages indicates that SOD1 mice behave like immunodeficient (ID) mice in terms of increased FMN loss and decreased functional recovery, through a mechanism that, paradoxically, is not inherent within the motoneuron itself, but, instead, involves a defect in peripheral immune: CNS glial cell interactions. The long-term goal of this project is to utilize our WT mouse model of immune-mediated neuroprotection after FNA as a template to elucidate how a malfunctioning peripheral immune system contributes to motoneuron cell loss in the SOD1 mouse model of ALS. Our central hypothesis is that CD4+ effector T cells provide neuroprotection to motoneurons through regulation of the central microglial and astrocytic response to peripheral nerve damage. There are 4 specific aims designed to: 1) elucidate the functional role of IL-10 in the WT facial nucleus following FNA, 2) determine if CD4+ T cells rescue FMN from FNA-induced cell death in RAG-2 KO mice through activation of the IL-10 cascade within the facial nucleus, 3) determine the mechanism that prevents CD4+T cell-mediated neuroprotection following FNA in the pre-symptomatic SOD1 mouse, and 4) test the ability of in vitro-generated, neuroprotective SOD1 CD4+ T cells to alter disease onset and/or progression in SOD1 mice. IL-10 reporter and conditional IL-10 knockout mice, along with adoptive transfer experiments with WT, ID and SOD1 mice, and laser capture microdissection will be used. Based on new data generated for this revision suggesting that SOD1 T cells are normal, but antigen-presenting cells (APC) are defective, SOD1 T cells and APC will be examined phenotypically and functionally both in vitro using relevant and irrelevant antigens and in vivo using adoptive transfer. Finally, adoptive immunotherapy with either neuroprotective FNA-specific T cells or APC into SOD1 mice will be done prior to disease onset, and the effects on disease onset, progression, and lifespan assessed. With respect to expected outcomes, the work is expected to identify key mechanistic elements in CD4+ T-mediated neuroprotection following FNA, reveal peripheral immune system defects following FNA in the SOD1 mouse model of ALS that prevent effective CD4+ T cell activation/differentiation and determine the therapeutic potential of adoptive immunotherapy with neuroprotective SOD1 T cells generated in vitro by FNA antigens. ALS strikes 30,000 Americans each year (15 cases a day), often at peak productive points in their lives and with enormous cost to affected individuals, their families, and the health care system. Identification of defects in neural:immune interactions will have an important positive impact because they can then be the target of therapeutic intervention in ALS treatment.