BLR&D Research Career Scientist Award Application

我的神经免疫学研究项目的使命是对以下方面进行深入的生物学理解： 影响中枢神经系统（CNS）的自身免疫、脱髓鞘和神经变性过程 并鉴定和测试可推向市场以治疗和/或治愈的新的疾病相关疗法 了以下条件退伍军人目前正在发展顽固的慢性神经系统疾病，如多种 硬化症（MS）和中风，与服务相关的损伤，包括创伤性脑损伤（TBI）和创伤后 应激障碍（PTSD），以及酒精和甲基苯丙胺的物质滥用。我们进行的研究 由于我们开发了一种新疗法， 靶向一种共同的潜在机制，即促进CNS慢性炎症的MIF/CD74轴 和其他组织。巨噬细胞移动抑制因子及其同系物D-多巴色素 互变异构酶）是高度炎性细胞因子，其在结合时触发其它炎性因子的释放 以及通过它们的共同受体CD74进行信号传导，CD74是一种用于将自身和外源肽装载到 抗原呈递细胞（APC）上的MHC II类分子。MIF/CD74信号转导的结果是肽特异性的 T效应细胞活化和炎症细胞从血液募集到CNS。我们最初独特的 一种称为RTL 1000的治疗性构建体由HLA-DR2的连接的DR α 1和DR β 1结构域（MS 风险因子）共价连接到髓鞘少突胶质细胞糖蛋白（MOG）35 - 55。此构建体具有 与天然存在的MHC II类/肽T细胞受体配体的构象相似性，但诱导T细胞 当以可溶形式存在时，APC上没有细胞结合的共刺激分子。该构建体 在MS小鼠模型中具有免疫调节和神经保护特性（实验性自身免疫性 在MS的1期研究中，RTL1000显示出安全性和良好的耐受性。 很快将在多剂量MS临床试验中进行测试。在理解药物的潜在作用方面的重大突破 RTL1000发生在2013年，发现CD74作为RTL1000的细胞受体。这导致 RTL1000可以竞争性抑制MIF和D-DT与CD74的结合， 短路MIF/CD74信号传导，其存在于基本上所有的VA靶向CNS病症中。分子 MIF结合的模型揭示了两个离散的CD74区域，其结合于MIF上的同源序列， D-DT和RTL 1000的DR α 1部分，从而解释了RTL 1000的竞争性抑制。然而，在这方面， RTL 1000仅可用于约60%表达HLA-DR2的MS受试者。因此，我们设计了一个新的 构建体DR α 1-MOG-35 - 55，其保留了RTL 1000的活性并可调节CD74和 竞争性阻断MIF结合，在慢性EAE中产生显著的治疗效果和神经保护作用。 有趣的是，RTL1000和DR α 1-MOG-35 - 55在治疗雄性小鼠的慢性EAE中更有效，因为 雌激素受体（ESR1）在女性中的拮抗作用。巨噬细胞移动抑制因子、D-DT和CD 74在~600 受试者临床研究（将发表在PNAS上）显示，具有高表达基因型的男性受试者 对于MIF（和D-DT），发生进行性MS的风险增加。 早期用RTL 1000或DR α 1-MOG-35 - 55治疗男性可能会防止转化为 进行性MS，并且可能有效治疗具有进行性疾病的MS受试者。FDA ind DR α 1-MOG-35 - 55临床前研究的批准将允许治疗所有MS受试者， HLA型由于其非多态性，普遍表达，将被所有人所容忍，因此 不需要组织分型就能注射。更重要的是，我们已经证明了RTL 1000和 DR α 1-MOG-35 - 55构建体还可以治疗实验小鼠模型中的其他CNS病症，包括 实验性脑卒中、血管性痴呆、创伤性脑损伤和甲基苯丙胺所致认知功能障碍 残疾，从而为发展这些毁灭性疾病的退伍军人提供了一种新的潜在疗法。

The mission of my Neuroimmunology Research Program is to develop a deep biological understanding of autoimmune, demyelinating and neurodegenerative processes that affect the central nervous system (CNS) and to identify and test novel disease-relevant therapies that can be brought to market to treat and/or cure these conditions. Veterans are currently developing intractable chronic neurological diseases such as multiple sclerosis (MS) and stroke, service related injuries including traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD), and substance abuse of alcohol and methamphetamine. Studies carried out by our laboratory are highly relevant to these devastating conditions due to our development of a novel therapy that targets a common underlying mechanism, the MIF/CD74 axis that promotes chronic inflammation in the CNS and other tissues. MIF (macrophage migration inhibitory factor) and its homolog D-DT (D-dopachrome tautomerase) are highly inflammatory cytokines that trigger release of other inflammatory factors upon binding and signaling through their common receptor, CD74, a chaperone for loading self and foreign peptides into MHC class II molecules on antigen presenting cells (APC). The result of MIF/CD74 signaling is peptide-specific Teffector cell activation and recruitment of inflammatory cells from blood into the CNS. Our initial unique therapeutic construct, called RTL1000 is comprised of linked DRα1 and DRβ1 domains of HLA-DR2 (an MS risk factor) covalently linked to myelin oligodendrocyte glycoprotein (MOG) 35-55. This construct has conformational similarity to naturally occurring MHC class II/peptide T cell receptor ligands, but induces T cell tolerance when present in soluble form without cell-bound co-stimulatory molecules on APC. This construct has immunoregulatory and neuroprotective properties in a mouse model of MS (experimental autoimmune encephalomyelitis, EAE) and was shown to be safe and well tolerated in a Phase 1 study in MS. RTL1000 will soon be tested in a multi-dose MS clinical trial. The major breakthrough in understanding the potent effects of RTL1000 occurred in 2013 with the discovery of CD74 as the cellular receptor for RTL1000. This led to the unifying discovery that RTL1000 could competitively inhibit binding of both MIF and D-DT to CD74 and thus short-circuit MIF/CD74 signaling that is present in essentially all of the VA targeted CNS conditions. Molecular modeling of MIF binding revealed two discrete CD74 regions that bound to homologous sequences on MIF and D-DT and to the DRα1 moiety of RTL1000, thus explaining RTL1000’s competitive inhibition. However, RTL1000 can only be used in ~60% of MS subjects that express HLA-DR2. We thus designed a new construct, DRα1-MOG-35-55 that retained the activities of RTL1000 and could modulate CD74 and competitively block MIF binding, resulting in a significant treatment effect and neuroprotection in chronic EAE. Of interest, RTL1000 and DRα1-MOG-35-55 were more effective in treating chronic EAE in male mice due to an antagonist effect of estrogen receptor (ESR1) in females. An evaluation of MIF, D-DT and CD74 in a ~600 subject clinical study (to be published in PNAS) revealed that male subjects with a high expression genotype for MIF (and D-DT) had an increased risk of developing progressive MS. This unique observation raises the possibility that early treatment of males with RTL1000 or DRα1-MOG-35-55 might prevent conversion to progressive MS and potentially would be effective for treating MS subjects with progressive disease. FDA IND approval of DRα1-MOG-35-55 preclinical studies would allow treatment of all MS subjects regardless of the HLA type due to its non-polymorphic, universal expression that would be tolerated by all humans and thus could be injected without tissue typing. Of broader importance, we have demonstrated that RTL1000 and DRα1-MOG-35-55 constructs can also treat other CNS conditions in experimental mouse models including experimental stroke, vascular dementia, traumatic brain injury and methamphetamine induced cognitive disability, thus providing a novel potential therapy for Veterans that develop these devastating conditions.