The "dark immunopeptidome" as a source of CD8 T cell epitopes in type 1 diabetes

“暗免疫肽组”作为 1 型糖尿病 CD8 T 细胞表位的来源

基本信息

批准号：
10589465
负责人：
Teresa P DiLorenzo
金额：
$ 61.66万
依托单位：
ALBERT EINSTEIN COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10589465
关键词：
Address Alleles Amino Acids Antigens Autoantigens Beta Cell Binding Bioinformatics CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes Cancer Patient Cell Separation Cells Clone Cells Code Collection Coupled Cytotoxic T-Lymphocytes Darkness Detection Development Digestion Disease Epitopes Foundations Future Generations HLA-A gene HLA-B Antigens Health Histocompatibility Antigens Class I Human Human Subject Research Hybrids Immune Targeting Immune response Immunologic Monitoring In Vitro Inbred NOD Mice Individual Infiltration Insulin Insulin-Dependent Diabetes Mellitus Insulinase Islet Cell Islets of Langerhans Knowledge Ligands Link MHC Class I Genes MHC binding peptide Mass Spectrum Analysis Messenger RNA Methods Modeling Morbidity - disease rate Nature Open Reading Frames Pathogenesis Pathogenicity Patients Peptides Peripheral Blood Mononuclear Cell Positioning Attribute Proinsulin Protein Databases Proteins Protocols documentation RNA Splicing Recommendation Reporting Research Project Grants Resources Sampling Secretory Vesicles Source Specimen Structure T cell response T-Cell Immunologic Specificity T-Lymphocyte T-Lymphocyte Epitopes T-Lymphocyte Subsets Testing Text Therapeutic Thymus Gland Work autoreactive T cell cell killing central tolerance human subject innovation interest islet mortality mouse model multicatalytic endopeptidase complex tumor

项目摘要

Enter the text here that is the new abstract information for your application. This section must be no longer than 30 lines of text. T cell responses to the beta cell autoantigen insulin are essential for efficient development of type 1 diabetes (T1D). An important emerging concept related to the essential nature of insulin as an autoantigen is that CD4+ T cell responses develop to unconventional insulin peptides, including hybrid peptides in which amino acids from insulin are linked to those from another protein (or another region of insulin). In the case of beta cell- cytotoxic CD8+ T cells, which are essential for beta cell killing, little is known about their ability to recognize unconventional insulin peptides. By analogy to hybrid peptides recognized by tumor-reactive CD8+ T cells isolated from cancer patients, hybrid insulin peptides presented on class I MHC molecules could be generated by proteasome-catalyzed peptide splicing. We have discovered that an H2-Db-bound hybrid insulin peptide is a ligand for beta cell-cytotoxic T cells in NOD mice, creating the first link between class I MHC-bound hybrid insulin peptides and T1D. Our project will test the hypothesis that spliced insulin peptides, and those derived from other non-canonical sources, are important targets of beta cell-cytotoxic CD8+ T cells in T1D. In Aim 1, we will use mass spectrometry to identify the immunopeptidome of human pancreatic islets expressing HLA-B*39:06 or A*24:02, both of which are predisposing for T1D, or A*02:01, commonly expressed by T1D patients. Limited information is available regarding the peptides presented by class I MHC molecules on primary human pancreatic islet cells. We are uniquely positioned to address this based on our robust protocols for the characterization of MHC-bound peptides, including from small samples, coupled with workflows that allow identification of spliced peptides and those derived from other non-canonical sources. Although our project will be focusing on such unconventional insulin peptides, all class I MHC-bound peptides will be identified. In Aim 2, we will investigate unconventional insulin peptides as CD8+ T cell epitopes in T1D and explore their importance in disease pathogenesis. Our recent development of NOD mouse models transgenically expressing human insulin along with HLA-B*39:06, A*24:02, or A*02:01 will allow us to examine the unconventional human insulin peptides identified in Aim 1 for recognition by islet-infiltrating CD8+ T cells. We will use these models and several complementary approaches to further assess the pathogenicity of the T cell specificities we identify. Islet- infiltrating CD8+ T cells from T1D patients will also be examined.

在此处输入文本，该文本是您的应用程序的新摘要信息。此部分的文本长度不得超过 30 行。 T 细胞对 β 细胞自身抗原胰岛素的反应对于 1 型糖尿病 (T1D) 的有效发展至关重要。与胰岛素作为自身抗原的本质相关的一个重要的新兴概念是，CD4+ T 细胞对非常规胰岛素肽产生反应，包括来自胰岛素的氨基酸与来自另一种蛋白质（或胰岛素的另一个区域）的氨基酸连接的混合肽。对于杀伤β细胞至关重要的β细胞毒性CD8+ T细胞来说，人们对它们识别非常规胰岛素肽的能力知之甚少。与从癌症患者中分离出的肿瘤反应性 CD8+ T 细胞识别的杂合肽类比，I 类 MHC 分子上呈递的杂合胰岛素肽可以通过蛋白酶体催化的肽剪接产生。我们发现，H2-Db 结合的混合胰岛素肽是 NOD 小鼠中 β 细胞毒性 T 细胞的配体，在 I 类 MHC 结合的混合胰岛素肽和 T1D 之间建立了第一个联系。我们的项目将检验这一假设：剪接胰岛素肽以及其他非经典来源的胰岛素肽是 T1D 中 β 细胞毒性 CD8+ T 细胞的重要靶标。在目标 1 中，我们将使用质谱法来鉴定表达 HLA-B*39:06 或 A*24:02 的人胰岛的免疫肽组，这两种物质都易患 T1D，或 A*02:01，通常表达为T1D 患者。关于 I 类 MHC 分子在原代人胰岛细胞上呈递的肽，可获得的信息有限。我们拥有独特的优势来解决这个问题，基于我们强大的 MHC 结合肽（包括小样本）表征方案，再加上能够识别剪接肽和其他非规范来源的肽的工作流程。尽管我们的项目将重点关注此类非常规胰岛素肽，但所有 I 类 MHC 结合肽都将被鉴定。在目标 2 中，我们将研究作为 T1D 中 CD8+ T 细胞表位的非常规胰岛素肽，并探讨它们在疾病发病机制中的重要性。我们最近开发的转基因表达人胰岛素以及 HLA-B*39:06、A*24:02 或 A*02:01 的 NOD 小鼠模型将使我们能够检查目标 1 中鉴定的非常规人胰岛素肽，以便通过胰岛浸润 CD8+ T 细胞。我们将使用这些模型和几种补充方法来进一步评估我们确定的 T 细胞特异性的致病性。来自 T1D 患者的胰岛浸润 CD8+ T 细胞也将被检查。