The role of Runx1 in the regulation of T cell anergy

Runx1在T细胞无反应性调节中的作用

• 批准号: 10311471
• 负责人: Drew N Wilfahrt
• 金额: $ 2.57万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-30 至 2022-01-17
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10311471
• 关键词: Address; Animals; Autoimmunity; Biology; Bone Marrow; Bypass; CD4 Positive T Lymphocytes; Candidate Disease Gene; Cell Maturation; Cell surface; Cells; Chimera organism; Complex; Data; Data Set; Defect; Development; Disease; Environment; Estrogen Receptors; Exhibits; Foundations; Frequencies; Gene Targeting; Immune Tolerance; Immune response; Immune system; In Vitro; Injections; Investigation; Knock-out; Lymphopenia; Maintenance; Modeling; Mus; Peripheral; Phenotype; Play; Population; Process; Proliferating; Regulation; Regulatory T-Lymphocyte; Research; Role; Self Tolerance; Signal Transduction; Stimulus; System; T cell anergy; T cell regulation; T cell response; T-Cell Development; T-Lymphocyte; Tamoxifen; Testing; Wild Type Mouse; Work; adaptive immune response; anergy; cell type; congenic; in vivo; insight; mouse model; novel; peripheral lymphoid organ; prevent; programs; response; transcription factor; transcriptome sequencing

Abstract: T cell anergy is a programmed state of cellular hyporesponsiveness that prevents the propagation of an immune response to self. Thus, anergy is a critical component of self-tolerance. Consequently, the development and maintenance of the anergy program in T cells is tightly controlled by many mechanisms, both cell-intrinsic and cell-extrinsic. Since anergy is important in self-tolerance, it is critical to understand the complex biology that regulates the initiation and regulation of the anergy program. We have found in wild-type (WT) mice that lower expression of the transcription factor Runx1 is associated with anergic T cells, defined by co-expression of the cell-surface markers CD73 and FR4. Furthermore, conditional deletion of Runx1 in T cells using a CD4-Cre produces a higher frequency of T cells that co-express CD73 and FR4. This supports the hypothesis that Runx1 suppresses the development of anergy in CD4+ T cells. CD4-Cre Runx1 cKO mice have a block in T cell maturation and have very few CD4+ T cells in peripheral lymphoid organs. To bypass this maturation defect, and test the role of Runx1 in peripheral CD4+ T cells, we have generated a novel 1:1 mixed bone marrow chimera (BMC) system using Estrogen Receptor (ER)-Cre Runx1 cKO bone marrow mixed with B6.SJL Wild Type (WT) bone marrow. This bypasses the maturation defect by deleting Runx1 in peripheral CD4+ T cells in a tamoxifen inducible manner after they have completed maturation. Furthermore, half the cells are Runx1-sufficient allowing for analysis of T cell-intrinsic effects. In this system, we have found that Runx1 regulates the cell-intrinsic induction of anergy, as increased frequency of co-expression of CD73 and FR4 in peripheral CD4+ T cells is only seen in the ER-Cre Runx1 cKO cells and not the B6.SJL WT cells derived from the same mouse. Aim 1 of the proposed studies will determine critical gene targets Runx1 regulates to control CD4+ T cell anergy. To do this, candidate genes identified by RNA-sequencing will be analyzed in our novel ER-Cre system, and their role in anergy will functionally assessed. Surprisingly, both the ER-Cre Runx1 cKO and the B6.SJL CD4+ T cells in the tamoxifen treated animals fail to proliferate upon in vitro TCR stimulus, suggesting that Runx1 regulates a cell-extrinsic signaling mechanism controlling tolerance. Aim 2 will define key mechanisms anergic Runx1-deficient CD4+ T cells use to tolerize wild type CD4+ T cells. To complete this aim we will examine the role of candidate genes in wild type cells. Further investigation of the role of Runx1 in CD4+ T cell anergy will provide insight into how the immune system initiates and maintains self-tolerance.

摘要：T细胞消极是一种编程的细胞性能不足的状态，可防止传播 对自我的免疫反应。因此，Anergy是自我耐受的关键组成部分。因此， T细胞中Anergy程序的开发和维护受许多机制的紧密控制，两者都 细胞中性和细胞锁骨。由于Anergy在自我耐​​受中很重要，因此了解 复杂的生物学，可调节Anergy程序的启动和调节。我们在野生型中发现 （wt）小鼠转录因子runx1的较低表达与厌食的T细胞相关，由 细胞表面标记CD73和FR4的共表达。此外，T细胞中RUNX1的条件缺失 使用CD4-CRE会产生较高的T细胞频率，该T细胞与CD73和FR4共表达。这支持 RUNX1抑制CD4+ T细胞中厌食的假设。 CD4-CRE RUNX1 CKO小鼠有 T细胞成熟的块，并且外周淋巴器官中的CD4+ T细胞很少。绕过这一点 成熟缺陷，并测试runx1在外围CD4+ T细胞中的作用，我们已经产生了一种新颖的1：1混合 使用雌激素受体（ER）-CRE RUNX1 CKO骨髓与混合的骨髓嵌合体（BMC）系统 B6.SJL野生型（WT）骨髓。这绕过了通过在外围删除runx1的成熟缺陷 CD4+ T细胞以他莫昔芬完成成熟后的诱导方式。此外，一半 细胞是runx1的足够的，可以分析T细胞中性效应。在这个系统中，我们发现 runx1调节厌食的细胞内诱导，因为CD73的共表达频率增加 外围CD4+ T细胞中的FR4仅在ER-CRE RUNX1 CKO细胞中可见，而不是B6.SJL WT细胞 源自同一鼠标。拟议的研究的目标1将确定关键基因靶标RUNX1 调节以控制CD4+ T细胞消极。为此，通过RNA测序确定的候选基因将是 在我们的新型ER-CRE系统中进行了分析，它们在Anergy中的作用将在功能上进行评估。令人惊讶的是，两个人 他莫昔芬治疗的动物中的ER-CRE RUNX1 CKO和B6.SJL CD4+ T细胞未能在 体外TCR刺激，表明RUNX1调节控制耐受性的细胞超支信号传导机制。 AIM 2将定义关键机制缺陷型CD4+ T细胞用来耐受野生型CD4+ T细胞。 为了完成此目标，我们将研究候选基因在野生型细胞中的作用。进一步调查 runx1在CD4+ T细胞中的作用将提供有关免疫系统如何启动和维护的洞察力 自我耐受。