The Origins of Human Anti-Insulin B Lymphocytes in Type 1 Diabetes

1 型糖尿病中人类抗胰岛素 B 淋巴细胞的起源

基本信息

批准号：
10343084
负责人：
Rachel H Bonami
金额：
$ 45.43万
依托单位：
VANDERBILT UNIVERSITY MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-12-01 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10343084
关键词：
Address Affinity Antigen-Presenting Cells Antigens Autoantibodies Autoantigens Autoimmune Autoimmune Diseases Autoimmune Responses Autoimmunity Avidity B cell clonality B cell differentiation B-Cell Antigen Receptor B-Cell Receptor Binding B-Lymphocyte Subsets B-Lymphocytes B-cell receptor repertoire sequencing Beta Cell Binding Biological Assay Biological Markers Blood Blood Volume Cell Death Cell Differentiation process Cells Cellular Indexing of Transcriptomes and Epitopes by Sequencing Child Clinical Clinical Trials Clonal Evolution Clonal Expansion Coal Code Dangerousness Data Detection Diabetes Mellitus Disease Disease Progression Epitope Mapping Epitopes Event Future Goals Heterogeneity Human Hybridomas IA-2 protein Immune Targeting Immune Tolerance Immune response Immune signaling Immunoglobulin Genes Immunoglobulin-Secreting Cells Immunoglobulins Individual Insulin Insulin-Dependent Diabetes Mellitus Intervention Investigation Investigational Therapies Islets of Langerhans Knowledge Lymphoma Maps Measures Memory Memory B-Lymphocyte Monitor Mus Mutate Mutation Participant Pathogenicity Pathologic Pathway interactions Patients Phenotype Population Process Production Recombinants Risk Role Sampling Sequence Analysis Serinus Shapes Signal Transduction Specificity Structure of germinal center of lymph node T-Lymphocyte Techniques Technology Testing Therapeutic Time Visit analysis pipeline antigen binding autoreactive B cell autoreactivity biobank defined contribution experimental study glucose tolerance human monoclonal antibodies immunological intervention impaired glucose tolerance inclusion criteria islet islet cell antibody molecular sequence database peripheral blood predictive marker prevent relapse prediction research clinical testing response screening single cell analysis

项目摘要

PROJECT SUMMARY B lymphocytes orchestrate autoimmune beta cell attack in type 1 diabetes (T1D) by presenting autoantigen to T cells which kill beta cells. Circulating insulin autoantibodies (IAAs) are not directly pathogenic but help predict T1D by signaling this dangerous B/T lymphocyte crosstalk. Immune targeting of insulin-producing beta cells occurs for months or even decades before symptomatic diabetes onset. Heterogeneity in diabetes progression and clinical trial responses slow the search for a T1D cure. Better biomarkers to identify and mechanistically explain responders are needed to overcome this bottleneck. Protective immune responses typically arise by T cell selection and affinity maturation of B lymphocytes in germinal centers, resulting in memory B lymphocyte and antibody-secreting cell differentiation. However, autoimmune responses do not always follow this pathway. For example, we find anti-insulin B cells (AIBCs) accelerate diabetes in T1D-prone mice, yet few AIBCs differentiate into IAA-secreting cells, despite entering germinal centers. To fill gaps in knowledge AIBC expansion early in T1D, we built a unique, carefully-curated biobank of pre-symptomatic T1D TrialNet participants. We find AIBCs in the peripheral blood of IAA-negative pre-symptomatic T1D donors, demonstrating B lymphocyte autoimmunity for insulin evades conventional detection via circulating IAAs in a subset of at-risk individuals. Longitudinal sampling and clinical testing at each T1D TrialNet visit provide opportunities to identify donor-specific changes as T1D progresses from stage 1 (normal glucose tolerance) to stage 2 (impaired glucose tolerance) and stage 3 (diabetes). We find AIBCs are skewed towards a memory B cell phenotype. Clonally-expanded, memory B lymphocytes express germline and minimally-mutated B cell receptors in stage 1 T1D donors. These data support our hypothesis that AIBCs expand and enter the memory compartment prior to glucose tolerance impairment, sometimes without IAA production. We will integrate AIBC phenotype, B cell receptor (immunoglobulin) sequence identity, clonal relatedness, B cell receptor affinity/avidity for insulin, and insulin epitope mapping to identify features that govern insulin recognition. High- throughput single cell analysis of B cell receptor repertoire paired with cell phenotype will identify changes in the same donor over time and with T1D stage progression to determine B lymphocyte repertoire and subset shifts that occur as glucose tolerance is lost. In addition to memory skewing, AIBCs show biased V and J immunoglobulin gene use. We will track this combination of features and use LIBRAseq to identify candidate autoreactive BCRs to recombinantly express and test for islet autoantigen recognition, including other known islet autoantigens (GAD65, IA-2, ICA512, and ZNT8). The human monoclonal antibodies, anti-insulin BCR sequence database, and analysis pipeline/code we will develop will be made publicly available. These studies are a necessary step towards using AIBCs as biomarkers in clinical trials to identify favorable changes in cellular autoimmunity and zero in on specific changes AIBCs undergo to deconvolute response heterogeneity.

项目概要 B 淋巴细胞通过向 1 型糖尿病 (T1D) 呈递自身抗原来协调自身免疫 β 细胞攻击 T 细胞杀死 β 细胞。循环胰岛素自身抗体 (IAA) 不直接致病，但有助于预测 T1D 通过发出这种危险的 B/T 淋巴细胞串扰信号来实现。产生胰岛素的β细胞的免疫靶向在症状性糖尿病发作前数月甚至数十年发生。糖尿病进展的异质性临床试验的反应减缓了对 T1D 治愈方法的探索。更好的生物标志物来识别和机械化解释需要响应者来克服这一瓶颈。保护性免疫反应通常由 T 引起生发中心B淋巴细胞的细胞选择和亲和力成熟，产生记忆B淋巴细胞和抗体分泌细胞分化。然而，自身免疫反应并不总是遵循这一途径。例如，我们发现抗胰岛素 B 细胞 (AIBC) 会加速易患 T1D 的小鼠罹患糖尿病，但 AIBC 却很少尽管进入生发中心，但仍分化为 IAA 分泌细胞。填补 AIBC 知识空白为了在 T1D 早期进行扩展，我们建立了一个独特的、精心策划的 T1D 症状前生物库 TrialNet 参与者。我们在 IAA 阴性症状前 T1D 捐献者的外周血中发现 AIBC，证明 B 淋巴细胞对胰岛素的自身免疫可以通过循环 IAA 来逃避常规检测高危个体的子集。每次 T1D TrialNet 访问时的纵向采样和临床测试提供随着 T1D 从第 1 阶段（正常糖耐量）发展到第 1 阶段，有机会识别供体特异性变化第 2 阶段（糖耐量受损）和第 3 阶段（糖尿病）。我们发现 AIBC 偏向于记忆 B 细胞表型。克隆扩增的记忆 B 淋巴细胞表达种系和最小突变的 B 细胞 1 期 T1D 供体中的受体。这些数据支持我们的假设：AIBC 扩展并进入内存糖耐量受损之前的隔室，有时不产生IAA。我们将整合AIBC 表型、B 细胞受体（免疫球蛋白）序列同一性、克隆相关性、B 细胞受体胰岛素的亲和力/亲和力，以及胰岛素表位作图，以确定控制胰岛素识别的特征。高的- B 细胞受体库的通量单细胞分析与细胞表型配对将识别同一供体随着时间的推移和 T1D 分期进展来确定 B 淋巴细胞库和子集当葡萄糖耐量丧失时发生的变化。除了内存偏差之外，AIBC 还表现出 V 和 J 偏差免疫球蛋白基因的使用。我们将跟踪这种特征组合并使用 LIBRAseq 来识别候选者自身反应性 BCR 重组表达并测试胰岛自身抗原识别，包括其他已知的胰岛自身抗原（GAD65、IA-2、ICA512 和 ZNT8）。人单克隆抗体，抗胰岛素BCR 我们将开发的序列数据库和分析管道/代码将公开。这些研究是在临床试验中使用 AIBC 作为生物标志物以确定有利变化的必要步骤细胞自身免疫和特定变化为零 AIBC 经历去卷积反应异质性。