Immunoregulation of Myelin Specific T Lymphocytes

多发性硬化症(MS)是一种破坏性的慢性、脱髓鞘的中枢神经系统自身免疫性疾病 系统(CNS)。两种关键的细胞因子/趋化因子被认为推动MS的早期炎症阶段向慢性 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 互变删除酶(D-dT)。我们的实验室设计了两个名为RTL1000的有效生物结构和第二个- 与α受体紧密结合并竞争性抑制的世代衍生物DR MIG1-MOG-35-55 MIF通过磷酸化的细胞外相关激酶(pERK1/2)结合和下游信号传导。 RTL1000/DRα1-MOG-35-55还靶向T细胞受体，从而抑制IL-2的释放，T细胞和 巨噬细胞的激活及其向中枢神经系统的迁移。实验性自身免疫小鼠的治疗 带有DRα1-MOG-35-55的脑脊髓炎(EAE-MS的动物模型)降低了急性 和慢性形式的疾病，在临床症状出现后服用，也会促进 神经保护。在上一次功绩审查资助期内获得的新调查结果已确定 为本次重新提交的研究提供坚实基础的几个关键事实，包括：1)详细说明 MIF和D-DT与其共同受体CD74的分子相互作用及其作用 对急性和慢性EAE疾病的严重性；2)DRQ的发现和表征，其效力是原来的8倍 用于人体临床试验的DRα1-MOG-35-55变体，称为DRHQ，[DRα1(L50Q)-Human(H)MOG-35-55]及其 [DRα1(L50Q)-MICE(M)MOG-35-55]，用于啮齿动物；以及3)演示 急性和慢性EAE的DRmQ治疗不仅阻断了通过MIF/CD74轴和T细胞的信号传导 细胞受体，但也抑制额外的促炎途径，促进神经保护。这个 在这一更新应用中需要解决的假设是DRQ可以抑制炎症的先天和适应性 免疫途径，同时刺激重新髓鞘形成和神经元保护。会议的主要目标是 目前的赠款申请是评估MIF/CD74轴与MIF/CD74轴之间可能的促炎作用 在EAE中髓系细胞-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、CXCR2(抑制少突胶质前体细胞增殖)和TCR，并同时 增强TREM-2和几种趋化因子配体和受体对的三条神经保护通路 与细胞因子/趋化因子筛选研究有关。DRQ抑制的这个三联谱 MIF/CD74、TREM-1和脑源性T细胞活性及其对中枢神经系统髓鞘再生的刺激作用 而EAE的轴突健康将验证DRhQ对MS的独特治疗潜力，并允许这一新的 与当前和未来的单抗以及其他目前批准的药物竞争的“设计者”药物 针对单一靶点分子的多发性硬化症的治疗。

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.