Generating and Investigating Antigen-Deficient Islets in Autoimmune Diabetes

自身免疫性糖尿病中抗原缺陷胰岛的生成和研究

基本信息

批准号：
10493423
负责人：
THOMAS DELONG
金额：
$ 19.44万
依托单位：
UNIVERSITY OF COLORADO DENVER
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：
2021-09-22 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10493423
关键词：
Amino Acid Sequence Antigens Autoantigens Autoimmune Diabetes Beta Cell C-Peptide CD4 Positive T Lymphocytes CRISPR/Cas technology Cathepsins Cellular Assay Clone Cells Colorado Core Facility Data Development Diabetes Mellitus Disease Enzymes Epitope spreading Family Generations Genes Histology Human Hybrids Immune system Inbred NOD Mice Incidence Infiltration Insulin Insulin-Dependent Diabetes Mellitus Interferon Type II Islets of Langerhans Islets of Langerhans Transplantation Isoleucine Leucine Mass Spectrum Analysis Measures Mediating Modeling Mus Mutate Mutation Non obese Onset of illness Organ Donor Organelles Outcome Pathogenicity Patients Peptide Hydrolases Peptides Process Proinsulin Reagent Research Personnel Residual state Role T-Lymphocyte T-Lymphocyte Epitopes Transplant Recipients Tumor-infiltrating immune cells Universities autoreactive T cell autoreactivity cohort diabetic experimental study immunoregulation induced pluripotent stem cell insulin dependent diabetes mellitus onset islet mouse genetics non-diabetic non-genomic peripheral blood prevent success therapeutic target

项目摘要

PROPOSAL SUMMARY Hybrid Insulin Peptides (HIPs) are a new family of autoantigens in Type 1 Diabetes (T1D). These peptides form through covalent fusion of pro-insulin fragments to other beta-cell peptides. HIPs contain non-genomic amino acid sequences, making them plausible targets for autoreactive T cells. We demonstrated that HIP- reactive CD4 T cells trigger diabetes in non-obese diabetic (NOD) mice, are present in residual islets of organ donors with T1D, and can be detected at significantly elevated levels in the peripheral blood of recent-onset T1D patients. We also verified the presence of HIPs in human and murine islets by mass spectrometry. Our data indicate that the protease Cathepsin D is responsible for the generation of HIPs that are targeted by diabetes-triggering CD4 T cell clones. Here we will generate NOD mice carrying a mutation that prevents the generation of HIPs. We predict that HIP-deficient beta-cells of these mice cannot be recognized by pathogenic CD4 T cells and the mice will be protected from disease onset. We will analyze the islets of these mice to assess HIP-content and T cell infiltration. We will also study disease incidence in these mice and determine whether pathogenic CD4 T cell clones can transfer disease into these mice. Beta-cells, deficient of disease- critical autoantigens, could allow us to reverse autoimmune diabetes in NOD mice and humans without the need for immune-modulation or shielding of beta-cells through encapsulation.

提案摘要混合胰岛素肽 (HIP) 是 1 型糖尿病 (T1D) 中的一个新的自身抗原家族。这些肽通过将胰岛素原片段与其他 β 细胞肽共价融合而形成。 HIP 包含非基因组氨基酸序列，使它们成为自身反应性 T 细胞的合理靶点。我们证明了 HIP- 反应性 CD4 T 细胞在非肥胖糖尿病 (NOD) 小鼠中引发糖尿病，存在于器官的残余胰岛中患有 T1D 的捐献者，并且可以在新发病的外周血中检测到显着升高的水平 T1D 患者。我们还通过质谱验证了人类和小鼠胰岛中 HIP 的存在。我们的数据表明，蛋白酶组织蛋白酶 D 负责生成 HIP，这些 HIP 的目标是引发糖尿病的 CD4 T 细胞克隆。在这里，我们将生成携带突变的 NOD 小鼠，该突变可阻止 HIP 的产生。我们预测这些小鼠的 HIP 缺陷型 β 细胞不能被致病菌识别。 CD4 T 细胞和小鼠将受到保护，免受疾病的影响。我们将分析这些小鼠的胰岛评估 HIP 含量和 T 细胞浸润。我们还将研究这些小鼠的疾病发生率并确定致病性 CD4 T 细胞克隆是否可以将疾病转移到这些小鼠体内。 β细胞，缺乏疾病- 关键的自身抗原，可以让我们逆转 NOD 小鼠和人类的自身免疫糖尿病，而无需需要通过封装来免疫调节或屏蔽 β 细胞。