Repertoire selection of AQP4-specific T cells that cause CNS autoimmunedisease

引起中枢神经系统自身免疫性疾病的 AQP4 特异性 T 细胞的库选择

• 批准号: 10059165
• 负责人: SCOTT S ZAMVIL
• 金额: $ 43.88万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-12-24 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10059165
• 关键词: Adoptive Transfer; Advanced Development; Affinity; Alleles; Amino Acid Sequence; Animals; Antibodies; Autoantigens; Autoimmunity; B-Lymphocytes; Binding; CNS autoimmune disease; CNS autoimmunity; Cells; Cerebrospinal Fluid; Clinical; Clone Cells; Data; Defect; Development; Epitopes; Exhibits; Experimental Models; Foundations; Genes; Goals; HLA-DRB1; Histologic; IgG1; Immune response; Immunization; Immunotherapy; Inflammation; Interleukin-17; Lesion; Mediating; Modeling; Multiple Sclerosis; Mus; Myelin; Neuromyelitis Optica; Optical Coherence Tomography; Organ Model; Paralysed; Pathogenesis; Pathogenicity; Pathology; Patients; Peptides; Peripheral; Phenotype; Rattus; Regulation; Role; T cell regulation; T cell response; T-Cell Proliferation; T-Cell Receptor; T-Lymphocyte; T-Lymphocyte Epitopes; T-cell receptor repertoire; Testing; Thymic epithelial cell; Thymus Gland; Tissues; Transgenic Mice; Transgenic Organisms; Visual system structure; Wild Type Mouse; aquaporin 4; base; cytokine; in vivo; insight; novel; peptide P; programs; response; success; targeted treatment

PROJECT SUMMARY / ABSTRACT Based upon the observation that aquaporin-4 (AQP4)-specific antibodies are IgG1, a T cell-dependent isotype, it was hypothesized that aquaporin-4 (AQP4)-specific T cells have a key role in neuromyelitis optica (NMO) pathogenesis. AQP4-specific T cells have been identified in NMO patients and, in comparison to healthy controls (HC), AQP4-reactive T cells are expanded and exhibit Th17 polarization, findings that further support the role of Th17 cells in NMO. Unfortunately, it is not feasible to evaluate how AQP4-reactive T cells participate directly in CNS inflammation in NMO patients. Thus, it is important to develop models to evaluate the potential role of AQP4-specific T cells in NMO. Initial attempts in generating an in vivo AQP4-based NMO model in wild-type (WT) mice and rats have not met with success. Recently, it was observed that pathogenic AQP4-specific T cells exist in AQP4-deficient (AQP4-/-) mice. Those T cells recognize two novel determinants. In comparison to other AQP4 determinants identified in WT mice, the novel determinants induce robust proliferation in AQP4-/- mice, but only a weak response in WT mice. Hyper-reactivity is AQP4-specific, but not epitope-specific as we discovered a second AQP4 epitope induced vigorous proliferation in AQP4- /-, but not WT, mice. The T cell receptor (TCR) repertoires used for recognition of these determinants in AQP4-/- and WT mice are distinct. T cells reactive to these determinants isolated from AQP4-/- donor mice induced clinical and histologic CNS autoimmune disease in 100% of recipient WT mice tested. Collectively, these findings represent the first successful induction of clinical AQP4-targeted CNS autoimmunity. Our findings suggest responses to those epitopes in AQP4-/- mice reflect a loss of central T cell tolerance. Findings from studying mice deficient in T cells only or B cells only indicate that peripheral T cell regulation also alters expression of pathogenic AQP4-specific T cells. We propose to test our hypothesis that there is a defect in thymic negative selection of AQP4-specific T cells in mice, a possibility that may be relevant to NMO pathogenesis. We will examine how peripheral T cell regulation may influence pathogenic AQP4-specific immune responses. In Specific Aim 1, by using unique approaches and novel mice, we will characterize the phenotype of pathogenic AQP4-specific T cells and generate AQP4-specific TCR transgenic mice. In Specific Aim 2, we will characterize the repertoire of AQP4-specific T cells in AQP4-/- and WT mice that express HLA- DR17 (DRB1*0301), the MHC II allele most highly associated with NMO. Separately, we will examine AQP4-specific T cell responses in NMO patients to determine if DR17-restricted AQP4-specific T cell epitopes identified those mice correspond to AQP4 T cell epitopes in NMO patients. In preliminary data, using these mice we discovered a novel HLA- DR17-restricted AQP4 determinant, and observed that it is recognized by T cells from HLA-DR17+ NMO patients, findings that support feasibility of this aim. Findings obtained in this program should elucidate mechanisms controlling development of pathogenic AQP4-specific T cells in NMO, provide a foundation advancing development of in vivo NMO models, and may provide insight for development of selective NMO immunotherapy.

项目摘要 /摘要 基于以下观察结果：Aquaporin-4（AQP4）特异性抗体是IgG1，是T细胞依赖性同种型，它是 假设Aquaporin-4（AQP4）特异性T细胞在Optica（NMO）发病机理中具有关键作用。 NMO患者已鉴定出AQP4特异性T细胞，与健康对照组（HC）相比，AQP4反应性 T细胞扩展并表现出Th17极化，结果进一步支持Th17细胞在NMO中的作用。 不幸的是，评估AQP4反应T细胞如何直接参与NMO中的CNS炎症是不可行的 患者。因此，开发模型以评估AQP4特异性T细胞在NMO中的潜在作用很重要。 在野生型（WT）小鼠中生成基于体内AQP4的NMO模型的初步尝试尚未遇到 成功。最近，观察到致病性AQP4特异性T细胞存在于AQP4缺陷型（AQP4 - / - ）小鼠中。那些t 细胞识别两个新型决定因素。与在WT小鼠中鉴定出的其他AQP4决定因素相比 决定因素会在AQP4 - / - 小鼠中诱导强大的增殖，但在WT小鼠中仅弱反应。超反应性是 AQP4特异性，但不是表位特异性的，因为我们发现第二个AQP4表位在AQP4-- / - ，但不是wt，老鼠。用于识别AQP4 - / - 和WT中这些决定因素的T细胞受体（TCR）曲目 小鼠是不同的。 T细胞反应从AQP4 - / - 供体小鼠分离的这些决定因素诱导的临床和组织学 CNS自身免疫性疾病在100％接受测试的受体WT小鼠中。总的来说，这些发现代表了第一个成功 临床AQP4靶向的CNS自身免疫的诱导。我们的发现表明对AQP4 - / - 小鼠中这些表位的反应 反映中央T细胞耐受性的丧失。仅研究缺乏T细胞或B细胞的小鼠的发现仅表明 周围T细胞调节还改变了致病性AQP4特异性T细胞的表达。 我们建议测试我们的假设，即小鼠AQP4特异性T细胞的胸膜阴性选择缺陷， 可能与NMO发病机理有关的可能性。我们将研究周围T细胞调节如何影响 致病性AQP4特异性免疫反应。在特定的目标1中，通过使用独特的方法和新颖的老鼠，我们将 表征致病性AQP4特异性T细胞的表型并生成AQP4特异性TCR转基因小鼠。在 具体目标2，我们将表征AQP4 - / - 和WT小鼠中AQP4特异性T细胞的曲目，这些小鼠表达HLA-- DR17（DRB1*0301），MHC II等位基因与NMO高度相关。另外，我们将检查AQP4特异性t NMO患者的细胞反应确定DR17限制的AQP4特异性T细胞表位是否确定了这些小鼠 对应于NMO患者的AQP4 T细胞表位。在初步数据中，使用这些小鼠，我们发现了一种新型的HLA- DR17限制的AQP4决定因素，并观察到它被HLA-DR17+ NMO患者的T细胞识别 支持此目标可行性的发现。该程序中获得的发现应阐明控制的机制 NMO中致病性AQP4特异性T细胞的开发，为体内NMO的发展提供了基础 模型，并可能为开发选择性NMO免疫疗法提供见解。