Mechanisms of regulatory T cell processes by IL-2

IL-2 调节 T 细胞过程的机制

• 批准号: 10313107
• 负责人: Acacia Nicole Crouch
• 金额: $ 5.1万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10313107
• 关键词: ATAC-seq; Ablation; Acute; Address; Adoptive Transfer; Adrenal Cortex Hormones; Affect; American; Animals; Apoptosis; Autoimmune Diseases; Autoimmunity; Bioinformatics; Biological; Biological Assay; Biology; Bypass; Cause of Death; Cell physiology; Complex; Complication; Data; Defect; Development; Disease; Dose; Drops; Epigenetic Process; Evaluation; Exhibits; Fellowship; Flow Cytometry; Genetic Risk; Genetic Transcription; Heterogeneity; Homeostasis; Human; IL2RA gene; Immune; Incidence; Inflammatory; Insulin-Dependent Diabetes Mellitus; Interleukin 2 Receptor; Interleukin-2; Investigation; Knock-out; Knockout Mice; Knowledge; Lead; Lupus; Malignant Neoplasms; Manipulative Therapies; Measures; Mediating; Memory; Metabolism; Modeling; Molecular; Mus; Mutation; Pathway interactions; Peripheral; Play; Population; Positioning Attribute; Prevention; Process; Receptor Signaling; Recombinant Interleukin-2; Regulatory T-Lymphocyte; Research; Role; Self Tolerance; Signal Transduction; Techniques; Therapeutic; Training; Transcription Process; Woman; autoreactive T cell; cytokine; experience; improved; in vitro Assay; in vivo; middle age; mouse model; mutant; overtreatment; peripheral tolerance; side effect; tool; transcriptome sequencing

Autoimmune disease is one of the leading causes of death for young and middle-aged women in the US. These diseases are mediated by autoreactive T cells, which are naturally contained by T regulatory cells (Tregs). Non-functional mutations in the IL-2 receptor (IL-2R) lead to autoimmunity due to deficiencies in Treg survival and function. This finding is corroborated by in vivo mouse models, leading to the widespread conclusion that IL-2 is important for Treg survival. However, recent data indicates this is oversimplified. Our lab studies a mouse model in which the alpha chain (CD25) of the IL-2R on peripheral Tregs is conditionally ablated. CD25 knockout Tregs demonstrate a disproportionate loss of central Tregs, which are long-lived circulating Tregs that give rise to effectors to maintain self-tolerance. Bulk knockout Tregs also display disruptions in critical Treg processes such as proliferation, survival, metabolism and suppressive function. Additionally, there is an absence of highly suppressive terminally differentiated Tregs in IL-2R mutant animals, indicating IL-2 may regulate the development of highly suppressive Tregs required for maintain peripheral tolerance. Given these findings, IL-2 signaling controls processes that are essential for the prevention of autoimmunity and understanding this role can provide therapeutic avenues to manipulate this population. Aim 1 will determine the effects of IL-2 on survival, proliferation, function and metabolism in Treg subsets. Using flow cytometry and in vitro assays, proliferation, apoptosis, survival, function and metabolism will be examined in Tregs subsets with and without IL-2 signaling. This aim will inform the extent to which IL-2 regulates cellular processes in Tregs subsets to further define the way by which IL-2 maintains Treg populations. Aim 2 will evaluate the role of IL-2 in Treg differentiation and heterogeneity. Due to defects observed in the differentiation of Tregs in the setting of IL-2, this aim will use adoptively transferred Treg subsets with and without IL-2 signaling to determine how IL-2 regulates development of eTregs from cTregs. Aim 3 will define the distinct IL-2 dependent transcriptional and epigenetic processes in cTregs versus eTregs. This aim will harness high throughput techniques such as RNAseq and ATAC-seq to correlate epigenetic and transcriptional changes as a consequence of IL-2 signaling, or lack thereof, in Treg subsets. By defining IL-2-dependent pathways and cellular processes that differ between them, these findings will be integrated with those in aim 1 to provide a clear role for IL-2 in regulating the cellular processes in each Treg subset. The main objective of this fellowship research is to define IL-2 driven processes coordinating Treg survival and homeostasis that are acutely relevant for understanding therapeutic applications of this cytokine and broadly relevant for understanding autoimmune disease.

自身免疫性疾病是美国中青年女性死亡的主要原因之一。 这些疾病是由自身反应性 T 细胞介导的，而自身反应性 T 细胞天然包含在 T 调节细胞中 （特雷格斯）。 IL-2 受体 (IL-2R) 的非功能性突变会因 Treg 缺陷而导致自身免疫 生存和功能。这一发现得到了体内小鼠模型的证实，从而导致了广泛的研究 结论是 IL-2 对于 Treg 的存活很重要。然而，最近的数据表明这过于简单化了。我们的实验室 研究了一种小鼠模型，其中外周 Tregs 上 IL-2R 的 α 链（CD25）有条件地 消融。 CD25 敲除 Tregs 表现出长寿的中枢 Tregs 的不成比例的损失 循环Tregs产生效应子以维持自我耐受。批量敲除 Tregs 也显示 关键 Treg 过程的破坏，如增殖、存活、代谢和抑制功能。 此外，IL-2R 突变动物中不存在高度抑制性终末分化 Tregs， 表明 IL-2 可能调节维持外周血所需的高度抑制性 Tregs 的发育 宽容。鉴于这些发现，IL-2 信号传导控制对于预防疾病至关重要的过程 自身免疫和理解这一作用可以为操纵这一群体提供治疗途径。目的 图1将确定IL-2对Treg亚群的存活、增殖、功能和代谢的影响。 使用流式细胞术和体外测定，可以了解增殖、凋亡、存活、功能和代谢。 在有和没有 IL-2 信号传导的 Tregs 子集中进行检查。该目标将告知 IL-2 的作用程度 调节 Tregs 子集中的细胞过程，进一步定义 IL-2 维持 Treg 的方式 人口。目标 2 将评估 IL-2 在 Treg 分化和异质性中的作用。由于缺陷 在 IL-2 环境中观察到 Treg 的分化，该目标将使用过继转移的 Treg 具有和不具有 IL-2 信号传导的子集，以确定 IL-2 如何调节 cTreg 发育为 eTreg。 目标 3 将定义 cTreg 与 eTreg。这一目标将利用 RNAseq 和 ATAC-seq 等高通量技术来关联 Treg 亚群中 IL-2 信号传导或缺乏 IL-2 信号传导导致的表观遗传和转录变化。经过 定义 IL-2 依赖性途径和它们之间不同的细胞过程，这些发现将是 与目标 1 中的内容相结合，以明确 IL-2 在调节每个 Treg 细胞过程中的作用 子集。该奖学金研究的主要目标是定义协调 Treg 的 IL-2 驱动过程 生存和稳态与了解该细胞因子的治疗应用密切相关 并与了解自身免疫性疾病广泛相关。