Immunoregulation of Myelin Specific T Lymphocytes

多发性硬化（MS）是一种严重的慢性、脱髓鞘性自身免疫性中枢神经系统疾病 系统（CNS）。两种关键的细胞因子/趋化因子被认为将MS的早期炎症阶段驱动为慢性炎症阶段。 进展期是巨噬细胞移动抑制因子（MIF）及其同系物D-多巴色素 互变酶（D-DT）。我们的实验室设计了两种有效的生物结构，称为RTL 1000和第二个- 第二代衍生物DRα1-MOG-35-55，与MIF受体CD 74紧密结合，竞争性抑制 通过磷酸化细胞外相关激酶（pERK 1/2）的MIF结合和下游信号传导。 RTL 1000/DRα1-MOG-35-55还靶向T细胞受体，导致抑制IL-2释放、T细胞和 巨噬细胞活化及其向CNS的迁移。治疗实验性自身免疫小鼠 用DRα1-MOG-35-55治疗脑脊髓炎（EAE -MS的动物模型）， 和慢性形式的疾病，并且还促进 神经保护在上一个Merit Review资助期内获得的新发现已经确定 几个关键事实，为本次重新提交的研究提供了坚实的基础，包括：1）详细 了解MIF和D-DT与其共同受体CD 74的分子相互作用及其作用 急性和慢性EAE疾病严重程度的影响; 2）DRQ的发现和表征，其效力高出约8倍 DRα1-MOG-35-55的变体，称为DRhQ，[DRα1（L50 Q）-人（h）MOG-35-55]，用于人体临床试验， 同源物，DRmQ，[DRα1（L50 Q）-小鼠（m）MOG-35-55]，创建用于啮齿动物;和3）证明 DRmQ治疗急性和慢性EAE不仅阻断了通过MIF/CD 74轴和T细胞的信号传导， 细胞受体，而且还抑制额外的促炎通路并促进神经保护。的 在本更新申请中要解决假设是DRQ可以抑制先天性和适应性炎症 免疫途径，同时刺激髓鞘再生和神经元保护。的主要目标 目前的拨款申请是评估MIF/CD 74轴与 EAE中髓样细胞-1（TREM-1）通路上表达的触发受体;并确定DRmQ是否可以 阻断TREM-1、CXCR 2（抑制少突胶质细胞前体增殖）和TCR，同时 增强涉及TREM-2和几种趋化因子配体和受体对的三种神经保护途径 与细胞因子/趋化因子筛选研究有关。DRQ抑制的三联体谱 MIF/CD 74、TREM-1和致脑炎性T细胞活性及其对CNS髓鞘再生的刺激作用 和轴突健康将验证DRhQ对MS的独特治疗潜力，并允许这种新的 “设计师”药物与当前和未来的单克隆抗体和其他目前批准的药物竞争 针对单一靶分子的MS疗法。

Multiple sclerosis (MS) is a devastating chronic, demyelinating autoimmune diseases of the central nervous system (CNS). Two key cytokines/chemokines thought to drive the early inflammatory stage of MS to a chronic progressive phase are macrophage Migration Inhibitory Factor (MIF) and its homolog D-Dopachrome Tautomerase (D-DT). Our laboratory designed two potent biological constructs called RTL1000 and a second- generation derivative, DRα1-MOG-35-55, that bind tightly to the MIF receptor, CD74, and competitively inhibit MIF binding and downstream signaling through phosphorylated extracellular-related kinase (pERK1/2). RTL1000/DRα1-MOG-35-55 also targets T cell receptors resulting in the inhibition of IL-2 release, T cell and macrophage activation and their migration into the CNS. Treatment of mice with experimental autoimmune encephalomyelitis (EAE – an animal model of MS) with DRα1-MOG-35-55 reduces the severity of both the acute and chronic forms of the disease when administered after onset of clinical signs and also promotes neuroprotection. New findings obtained during the previous Merit Review funding period have established several key facts that provide a solid basis for the studies proposed in this resubmission, including: 1) Detailed understanding of MIF and D-DT molecular interactions with their common receptor, CD74 and their contributions to acute and chronic EAE disease severity; 2) Discovery and characterization of DRQ, an ~8-fold more potent variant of DRα1-MOG-35-55 called DRhQ, [DRα1(L50Q)-human (h)MOG-35-55] for human clinical trials and its homolog, DRmQ, [DRα1(L50Q)-mouse (m)MOG-35-55] that was created for use in rodents; and 3) Demonstration that DRmQ treatment of acute and chronic EAE not only blocks signaling through the MIF/CD74 axis and the T cell receptor, but also inhibits additional proinflammatory pathways and promotes neuroprotection. The hypothesis to be addressed in this renewal application is that DRQ can inhibit inflammatory innate and adaptive immune pathways and simultaneously stimulate remyelination and neuronal protection. The major goals of the current grant application are to evaluate possible proinflammatory interactions between the MIF/CD74 axis with the triggering receptor expressed on myeloid cells-1 (TREM-1) pathway in EAE; and to determine if DRmQ can block TREM-1, CXCR2 (which inhibits oligodendrocyte precursor proliferation) and the TCR and simultaneously enhance three neuroprotective pathways involving TREM-2 and several chemokine ligand and receptor pairs that were implicated in cytokine/chemokine screening studies. This triad spectrum of DRQ inhibition of MIF/CD74, TREM-1 and encephalitogenic T cell activity coupled with its stimulatory effects on CNS remyelination and axonal health in EAE will validate the unique therapeutic potential of DRhQ for MS and allow this novel “designer” drug to compete favorably with current and future monoclonal antibody and other currently approved therapies for MS that are directed at single target molecules.