Damage Associated Molecular Patterns and Regenerative Failure in MS

多发性硬化症中损伤相关的分子模式和再生失败

• 批准号: 10327692
• 负责人: TIMOTHY VARTANIAN
• 金额: $ 36.91万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-12-01 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10327692
• 关键词: Animal Model; Animal Testing; Astrocytes; Axon; Biological Assay; Biological Models; Cell Maturation; Cells; Chemicals; Chronic; Cicatrix; Clinical; Clinical Research; Cuprizone; Data; Demyelinations; Disease; Effectiveness; Extracellular Matrix; Failure; Family; Generations; Goals; Health; Histopathology; Immunotherapy; Individual; Inflammatory; Injury; Innate Immune Response; Instruction; Knockout Mice; Lesion; Libraries; Microscopy; Modeling; Modification; Molecular; Molecular Target; Multiple Sclerosis; Multiple Sclerosis Lesions; Mus; Myelin; Natural regeneration; Nerve Degeneration; Nervous System Physiology; Neurons; Oligodendroglia; Pathologic Processes; Pathway interactions; Pattern; Pattern recognition receptor; Pharmaceutical Preparations; Pharmacology; Phase; Phenotype; Play; Pre-Clinical Model; Predisposition; Role; Secondary to; Signal Pathway; Signal Transduction; Site; Slice; TLR2 gene; Testing; Tissues; Toll-like receptors; Ursidae Family; Work; antagonist; astrogliosis; base; cell injury; chronic demyelination; clinically relevant; disabling disease; effectiveness testing; experimental study; extracellular; high throughput screening; in vivo; novel; oligodendrocyte lineage; oligodendrocyte progenitor; pre-clinical; preclinical study; prevent; receptor; recruit; regenerative; remyelination; response; small molecule; stem cells; tissue injury; young adult

Multiple Sclerosis (MS) is a common disabling disease of young adults. Despite intense immune therapies, relentless progression continues to occur for reasons that are poorly understood. Our overall hypothesis is that Danger/Damage Associated Molecular Patterns (DAMPs) within MS lesions function to inhibit remyelination by preventing the maturation of both oligodendrocyte progenitor cells (OPCs) and premyelinating oligodendrocytes into myelinating oligodendrocytes through activation of the TLR2/MyD88 pathway. We have previously shown that in the presence of DAMPs OPC maturation into myelinating oligodendrocytes is blocked and that in constitutive TLR2 knock-out mice, complete remyelination occurs despite the presence of DAMPs. Our objectives in this application are to provide convincing mechanistic support that DAMPs function in vivo by directly targeting the oligodendrocyte lineage and to identify small molecule antagonists to the TLR2/MyD88 pathway that promote remyelination in MS relevant preclinical models. In the first aim we will compare remyelination in mice harboring cell specific deletions of either TLR2 or MyD88 with strain matched wild-type controls using the chronic cuprizone model. We will assess the impact of TLR2 or MyD88 deletion on the histopathology relevant to chronic demyelination: microglial phenotype, astrogliosis and astrocytic scar, and axonal health. In aim two we will test pharmacologic antagonists to the TLR2/MyD88 pathway for their ability to promote remyelination in MS relevant preclinical models. Using 34 potential TLR2/MyD88 antagonists that we identified in a high throughput screen of pharmacologically active compounds, we will first validate these agents as TLR2/MyD88 antagonists and determine their molecular target in the TLR2/MyD88 pathway. Validated TLR2/MyD88 antagonists will be tested in cerebellar explant organotypic cultures for effectiveness on promoting remyelination. Compounds that induce remyelination in cerebellar explants will then move forward for testing in preclinical animal models. Two models of remyelination will be assessed based on their inherent lack of remyelination under control conditions. The first model is chronic, 12 week, cuprizone, which fails to effectively remyelinate in contrast to the traditional 6-week cuprizone model. The second model is stereotactic focal demyelination with the addition of an MS relevant DAMP, which fails to remyelinate. The value of these models is that they bear clinical relevance to remyelinative failure in MS. Drugs that promote remyelination in these MS relevant preclinical models will then be investigated in greater detail for their pharmacologic targets and their impact on the histopathology of remyelination. We chose to screen a library of pharmacologically active compounds such that agents active in our preclinical models can move forward directly to phase II clinical trail. The unique features of this project are: 1) identification of DAMP signaling and the TLR2/MyD88 pathway as relevant to CNS remyelination; 2) the use of preclinical models that have inherent remyelinative failure; and 3) a clear path forward from preclinical studies to clinical research. !

多发性硬化症（MS）是年轻人常见的致残性疾病。尽管进行了强烈的免疫治疗， 由于人们知之甚少的原因，这种无情的进展继续发生。我们的总体假设是 MS 病变内的危险/损害相关分子模式 (DAMP) 具有抑制作用 通过阻止少突胶质细胞祖细胞 (OPC) 的成熟和髓鞘形成前的髓鞘再生 通过激活 TLR2/MyD88 通路，少突胶质细胞转变为髓鞘少突胶质细胞。我们有 先前表明，在 DAMP 存在的情况下，OPC 成熟为髓鞘少突胶质细胞的过程被阻断 并且在 TLR2 组成型敲除小鼠中，尽管存在 DAMP，仍会发生完全髓鞘再生。 我们在此应用中的目标是通过以下方式为 DAMP 在体内发挥作用提供令人信服的机制支持： 直接靶向少突胶质细胞谱系并鉴定 TLR2/MyD88 的小分子拮抗剂 在 MS 相关临床前模型中促进髓鞘再生的途径。在第一个目标中，我们将比较 携带 TLR2 或 MyD88 细胞特异性缺失且品系匹配的野生型小鼠的髓鞘再生 使用慢性铜宗模型进行控制。我们将评估 TLR2 或 MyD88 缺失对 与慢性脱髓鞘相关的组织病理学：小胶质细胞表型、星形胶质细胞增生和星形细胞疤痕，以及 轴突健康。在目标二中，我们将测试 TLR2/MyD88 通路的药理拮抗剂的能力 促进 MS 相关临床前模型中的髓鞘再生。使用 34 种潜在的 TLR2/MyD88 拮抗剂 我们在药理活性化合物的高通量筛选中鉴定出，我们将首先验证这些 药物作为 TLR2/MyD88 拮抗剂，并确定它们在 TLR2/MyD88 途径中的分子靶点。 经验证的 TLR2/MyD88 拮抗剂将在小脑外植体器官型培养物中进行有效性测试 关于促进髓鞘再生。然后，诱导小脑外植体髓鞘再生的化合物将移动 期待在临床前动物模型中进行测试。两种髓鞘再生模型将根据它们的情况进行评估 在控制条件下固有地缺乏髓鞘再生。第一个模型是慢性的，12 周，cuprizone， 与传统的 6 周 cuprizone 模型相比，未能有效地进行髓鞘再生。第二个模型是 添加 MS 相关 DAMP 后发生立体定向局灶性脱髓鞘，但无法进行髓鞘再生。这 这些模型的价值在于它们与 MS 的髓鞘再生失败具有临床相关性。促进药物 然后将更详细地研究这些 MS 相关临床前模型中的髓鞘再生 药理靶点及其对髓鞘再生组织病理学的影响。我们选择筛选一个库 药理活性化合物，使我们的临床前模型中的活性药物能够向前发展 直接进入II期临床试验。该项目的独特之处在于：1）DAMP 信号传导的识别和 与中枢神经系统髓鞘再生相关的 TLR2/MyD88 通路； 2）使用具有固有特性的临床前模型 髓鞘再生失败； 3）从临床前研究到临床研究的明确前进道路。 ！