Regulation of CD4 T cell tolerance by the NR4A family of nuclear receptors

核受体 NR4A 家族对 CD4 T 细胞耐受性的调节

基本信息

批准号：
10707222
负责人：
JULIE ZIKHERMAN
金额：
$ 58.77万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-19 至 2027-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10707222
关键词：
Acute Agonist Anti-Inflammatory Agents Antigens Autoantibodies Autoantigens Autoimmune Responses B-Cell Activation B-Lymphocytes BCL2L11 gene Bacterial Artificial Chromosomes Biology Bone Marrow Bypass CD4 Positive T Lymphocytes Cell Compartmentation Cell Death Induction Cells Chimera organism Chronic Clonal Deletion Coupled DNA Binding Domain Data Disease Epigenetic Process Exhibits FOXP3 gene Family Family member Gene Expression Gene Expression Profile Genes Genetic Genetic Transcription Genomic approach Goals Homeostasis Immune Immune response Immunosuppression Impairment Inflammatory Interleukin-2 Knowledge Ligands Lymphocyte Mediating Molecular Mus NR4A1 gene NR4A2 gene Nuclear Nuclear Family Nuclear Hormone Receptors Nuclear Receptors Organ Transplantation Orphan Pattern Peripheral Phenocopy Phenotype Physiological Play Production Proliferating Publishing Radiation Chimera Regulation Regulatory T-Lymphocyte Reporter Repression Role Signal Transduction T cell anergy T cell response T-Cell Development T-Lymphocyte Testing Therapeutic Thymus Gland Tissues Transcriptional Regulation Vaccination anergy antagonist antigen-specific T cells autoreactive T cell chromatin remodeling cytokine defined contribution exhaust expectation genetic approach innovation member non-genomic novel novel therapeutics preservation programs response restraint small molecule thymocyte transcription factor transcriptome transcriptome sequencing tumor

项目摘要

Project Summary/Abstract This proposal’s long-term goal is to take advantage of the biology of the NR4A family of orphan nuclear hormone receptors to selectively manipulate antigen-specific T cell responses in immune-mediated diseases. NR4A members (NUR77, NURR1, and NOR1) are encoded by three genes (Nr4a1-3, respectively) that are rapidly induced by antigen (Ag) stimulation in lymphocytes. Although they are thought to function as ligand- independent, constitutively active transcription factors, small molecule agonist and antagonist ligands have been developed, rendering them druggable. We and others have shown that NR4A TF expression scales with the intensity of Ag stimulation, and are highly upregulated in thymocytes undergoing negative selection, in regulatory T cells (Tregs), as well as in self-reactive, anergic, or exhausted T cells. Due to an overlapping expression pattern and considerable structural homology in their DNA-binding domain, the NR4A TFs exhibit profound functional redundancy; thymic deletion of multiple - but not individual - NR4A family members (Nr4a1 and Nr4a3 >> Nr4a2, which is minimally expressed) results in severe Treg deficiency and a “scurfy-like” disease that phenocopies Foxp3-/- mice. Consequently, it has not been possible previously to unmask additional redundant functions of this family during thymic selection and in conventional mature CD4 T cells (Tconv). This represents a major gap in our knowledge that limits full therapeutic exploitation of these factors. Recently, we took advantage of both conditional genetic and bone marrow chimera strategies in order to preserve Treg homeostasis. Unexpectedly, mixed chimeras harboring both WT and Nr4a1-/- Nr4a3-/- (DKO) bone marrow rapidly develop anti-nuclear autoantibodies (ANAs) and a systemic inflammatory disease despite a replete Treg compartment of largely WT origin. This disease differs qualitatively from that seen in germline DKO mice with Treg-deficiency, and is B cell-extrinsic. We show that negative selection of DKO thymocytes is profoundly impaired in a cell-intrinsic manner. Consistent with escape of self-reactive T cells into the periphery, DKO CD4 Tconv cells expressing phenotypic and transcriptional markers of anergy accumulate in these chimeras. However, these self-reactive DKO cells nevertheless exhibit exaggerated proliferation and IL-2 production, suggesting that functional anergy is defective. We therefore hypothesize that the NR4A family play cell-intrinsic, but redundant, roles in both central and peripheral CD4 T cell tolerance. To test this hypothesis: In our first aim, we propose to define the role of the NR4A family in thymic negative selection in the face of both ubiquitous and tissue-restricted antigens, and to define the transcriptional targets that contribute to this function. In our second aim, we propose to isolate NR4A contributions to peripheral T cell tolerance, and to canonical features of mature CD4 T cell anergy - including impaired signal transduction, cytokine production, and proliferation. We will use both bulk and single cell genomic approaches to define the mechanism by which the NR4A family regulates the transcriptome and epigenetic profile of naïve and tolerant CD4 T cells.

项目摘要/摘要该提议的长期目标是利用NR4A孤儿核马的生物学在免疫介导的疾病中选择性操纵抗原特异性T细胞反应的受体。 NR4A成员（NUR77，NURR1和NOR1）由三个基因（NR4A1-3）编码为淋巴细胞中抗原（Ag）刺激迅速诱导。尽管它们被认为是配体的功能独立的，组成型活性的转录因子，小分子激动剂和拮抗剂配体已是开发，使它们可吸毒。我们和其他人已经表明NR4A TF表达式与 Ag刺激的强度，并在经历阴性选择的胸腺细胞中高度上调。 T细胞（Tregs）以及自反应性，厌食或耗尽的T细胞。由于表达模式重叠 NR4A TF在其DNA结合域中的结构同源性相当大，暴露了深刻的功能冗余;胸腺删除多重 - 但不是个体-NR4A家庭成员（NR4A1和NR4A3 >> NR4A2，最少表达的）导致严重的Treg缺乏症和一种“类似于曲折的”疾病 foxp3 - / - 鼠标。因此，以前不可能揭露该家族在胸腺选择期间和常规成熟的CD4 T细胞（TCONV）中。这代表了一个主要差距据我们所知，这些因素完全限制了对这些因素的全面剥削。最近，我们利用有条件的遗传和骨髓嵌合体策略来保存 Treg稳态。出乎意料的是，混合的嵌合体携带WT和NR4A1 - / - NR4A3 - / - （DKO）骨髓快速发展抗核自身抗体（ANA）和全身性炎症目的地 wt起源的隔室。这种疾病与在种系DKO小鼠中的质量不同 Treg缺乏症，是B细胞效力。我们表明，DKO胸腺细胞的阴性选择是深刻的以细胞中的方式受损。与自反应性T细胞逃脱到周围的DKO CD4一致表达表型和转录标记的TCONV细胞在这些嵌合体中积聚。但是，这些自反应性的DKO细胞仍然暴露了夸张的增殖和IL-2产生，表明功能性不足是有缺陷的。因此，我们假设NR4A家族在播放细胞中，但是在中央和外围CD4 T细胞耐受性中冗余作用。检验这一假设：在我们的第一个目标中，我们建议在面对两者的情况下定义NR4A家族在胸腺阴性选择中的作用无处不在和组织限制的抗原，并定义有助于该功能的转录靶标。在我们的第二个目标中，我们建议将NR4A贡献对外围T细胞的耐受性和规范贡献成熟CD4 T细胞消音的特征 - 包括信号转移受损，细胞因子产生和增殖。我们将同时使用批量和单细胞基因组方法来定义 NR4A家族调节幼稚和耐受性CD4 T细胞的转录组和表观遗传谱。