Structural, functional, and mechanistic anlaysis of autoreactive CD8 T cells

自身反应性 CD8 T 细胞的结构、功能和机制分析

• 批准号: 10335165
• 负责人: STEVEN C. ALMO
• 金额: $ 71.58万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-02-08 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10335165
• 关键词: Address; Alleles; Animal Model; Antigens; Area; Autoantigens; Autoimmune Diseases; Autoimmune Process; Autoimmunity; Beta Cell; Binding; Binding Proteins; Biochemical; Biological Assay; CD8-Positive T-Lymphocytes; CD8B1 gene; Cells; Cellular biology; Chimera organism; Clone Cells; Collection; Complement; Crystallography; Cytotoxic T-Lymphocytes; Development; Disease; Disease Resistance; Disease model; Exhibits; Future; G6PC2 gene; Goals; HLA-B Antigens; Health; Histocompatibility Antigens Class I; Human; Immune system; Immunology; Inbred NOD Mice; Insulin; Insulin-Dependent Diabetes Mellitus; Islets of Langerhans; Knowledge; Learning; Ligands; MHC Class I Genes; Maps; Mediating; Mus; Mutagenesis; Nature; Pathogenicity; Pathology; Patients; Peptide/MHC Complex; Peptides; Peripheral; Play; Predisposition; Process; Property; Protein Isoforms; Reagent; Recurrence; Resistance; Role; Structure; Susceptibility Gene; T cell response; T-Cell Receptor; T-Lymphocyte; T-Lymphocyte Epitopes; Testing; Work; adaptive immune response; autoreactive T cell; autoreactivity; base; biophysical techniques; cross reactivity; cytotoxic CD8 T cells; defined contribution; high throughput screening; in vivo; in vivo Model; innovation; interdisciplinary approach; islet; mouse model; novel; pathogen; protein protein interaction; receptor; therapeutic target; tumor

ABSTRACT CD8 T cells are important contributors to the pathology observed in many autoimmune diseases, including type 1 diabetes. Despite the importance of autoreactive CD8 T cells, much fundamental knowledge is lacking in several major areas, including i) the properties of class I MHC alleles that confer susceptibility or resistance to disease; ii) the determinants that underlie the promiscuous antigen recognition often displayed by autoreactive T cells; and iii) the contribution of the CD8αβ co-receptor in facilitating autoimmune processes. These are the critical knowledge gaps that we seek to fill, and we will do so using a multidisciplinary approach and a collection of innovative strategies, reagents, and animal models. In Aim 1, we will define the biochemical and structural features and in vivo peptide presentation properties of human class I MHC alleles associated with susceptibility or resistance to type 1 diabetes. These studies will focus on HLA-B*39:06, B*39:01, and B*38:01, a closely related group of class I MHC alleles that are differentially associated with disease. We will test the hypothesis that the differential ability of these three alleles to mediate disease is the consequence of differential binding and presentation of certain disease-relevant beta cell peptides. Our newly developed NOD mouse models expressing human insulin or human IGRP will be central to this aim. In Aim 2, we will use the T cell receptors from a set of promiscuous and autoreactive CD8 T cell clones in structural and mutagenesis studies to define the mechanisms that underlie T cell receptor cross-reactivity. Among other approaches, we will take advantage of novel high-throughput assays that we have developed both to identify T cell epitopes and map protein binding interfaces. In Aim 3, we will use biochemical and biophysical approaches and in vivo models to better understand the interaction between CD8αβ and peptide-MHC. Despite the requirement of CD8αβ for CD8 T cell selection and peripheral activation, and its potential as a therapeutic target, crystallographic analysis of its interaction with pMHC is limited to a single structure of murine CD8αβ with H-2Dd. Our own findings from mouse models we have recently characterized suggest that human CD8αβ may be interacting with class I MHC in a manner not revealed by the single available structure. While autoreactive CD8 T cells under study here are likely to exhibit some unique features due to their necessity to escape tolerance mechanisms, much of what will be learned will be fundamental knowledge that is generally applicable to CD8 T cell biology and that will help guide the future development of more effective approaches to manipulate and harness the immune system in health and disease.

抽象的 CD8 T细胞是在许多自身免疫性疾病中观察到的病理学的重要因素， 包括1型糖尿病。尽管自动反应性CD8 T细胞很重要，但许多基本知识 缺乏几个主要领域，包括i）会议易感性或 抵抗疾病； ii）基于滥交抗原识别的决定者经常显示 自动反应性T细胞； iii）CD8αβ共受体在促进自身免疫过程中的贡献。 这些是我们寻求填补的关键知识差距，我们将使用多学科的方法来做到这一点 以及创新策略，试剂和动物模型的集合。在AIM 1中，我们将定义 生化和结构特征以及人类I类MHC等位基因的体内肽表现特性 与对1型糖尿病的敏感性或耐药性有关。这些研究将重点介绍HLA-B*39：06， b*39：01，b*38：01，与I类MHC等位基因密切相关的组 疾病。我们将检验以下假设：这三个等位基因介导疾病的差异能力是 差异结合和某些与疾病相关的β细胞肽的呈现的结果。我们的新 表达人类胰岛素或人IGRP的开发的点头小鼠模型将是此目标的核心。在AIM 2中， 我们将在结构和 诱变研究以定义T细胞受体交叉反应性的机制。除其他 方法，我们将利用我们已经开发出来的新型高通量测定法 细胞表位和MAP蛋白结合界面。在AIM 3中，我们将使用生化和生物物理 接近和体内模型，以更好地了解CD8αβ与Peppere-MHC之间的相互作用。 尽管需要CD8αβ进行CD8 T细胞选择和外围激活，并且其潜力作为A 治疗目标，与PMHC相互作用的晶体学分析仅限于单个结构 带有H-2DD的鼠CD8αβ。我们最近从鼠标模型中表征的我们自己的发现表明 人CD8αβ可以以单个可用结构未揭示的方式与I类MHC相互作用。 虽然此处研究的自动反应性CD8 T细胞很可能会显示出一些独特的特征 逃避宽容机制的必要性，所学的许多知识将是基本知识 通常适用于CD8 T细胞生物学，这将有助于指导未来的开发更有效 操纵和利用健康和疾病的免疫系统的方法。