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，这是您应用程序的新摘要信息。本节必须不超过30行文本。 T细胞对β细胞自身抗原胰岛素的反应对于有效发展1型糖尿病（T1D）至关重要。与胰岛素作为自身抗原的基本性质相关的一个重要新兴概念是，CD4+ T细胞反应发展为非常规胰岛素肽，包括胰岛素的氨基酸与来自另一种蛋白质（或其他胰岛素另一个区域）的氨基酸相关的杂化肽。对于β细胞 - 细胞毒性CD8+ T细胞，对于β细胞杀伤至关重要，对它们识别非常规胰岛素肽的能力知之甚少。通过类似于从癌症患者中分离出的肿瘤CD8+ T细胞识别的杂化肽，可以通过蛋白酶体催化的肽剪接来产生在I类MHC分子上呈现的杂化胰岛素肽。我们发现，H2-DB结合的杂化胰岛素肽是NOD小鼠中β细胞 - 毒性T细胞的配体，在I类MHC结合的杂化胰岛素肽和T1D之间创建了第一个连接。我们的项目将检验以下假设：剪接的胰岛素肽以及从其他非典型来源衍生的肽是T1D中β细胞毒性CD8+ T细胞的重要靶标。在AIM 1中，我们将使用质谱法来鉴定表达HLA-B*39：06或A*24：02的人类胰岛的免疫肽组，这两种胰岛对T1D或A*02：01均倾向于T1D患者通常表达。有限的信息可获得有关I级MHC分子在原代人胰岛细胞上提出的肽的信息。我们的位置是基于我们的鲁棒方案来解决此问题，以表征MHC结合的肽，包括来自小样品，再加上工作流程，允许识别剪接肽和来自其他非统治来源的肽。尽管我们的项目将重点放在这种非常规的胰岛素肽上，但将确定所有I类MHC结合的肽。在AIM 2中，我们将研究非常规的胰岛素肽作为T1D中的CD8+ T细胞表位，并探索它们在疾病发病机理中的重要性。我们最近对小鼠模型以及HLA-B*39：06，A*24：02或A*02：01以及AIM 1中鉴定出的非常规的人类胰岛素肽识别的NOD小鼠模型以及A*02：01的转发。我们将使用这些模型和几种互补方法来进一步评估我们识别的T细胞特异性的致病性。还将检查来自T1D患者的胰岛浸润CD8+ T细胞。