Role of Cul4A in Governing Th2-Type Tolerance

Cul4A 在控制 Th2 型耐受中的作用

• 批准号: 9770641
• 负责人: Roza Insafetdinovna Nurieva
• 金额: $ 40万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9770641
• 关键词: Address; Airway Disease; Allergic Disease; Allergic inflammation; Asthma; Autoimmune Diseases; CD4 Positive T Lymphocytes; Cell physiology; Cells; Chromatin; Development; Evolution; Exhibits; Extrinsic asthma; Family; Gene Expression Microarray Analysis; Generations; Genes; Goals; Hematopoietic; Human; IgE; IgG1; Immune System Diseases; Immune Tolerance; Immune response; In Vitro; Infiltration; Inflammation; Inflammatory; Inflammatory Response; Interleukin-2; Interleukin-4; Knock-out; Knockout Mice; Mediating; Methods; Modeling; Molecular; Mus; Pathogenesis; Peripheral; Phenotype; Physiological; Prevention; Production; Property; Reagent; Regulation; Regulatory T-Lymphocyte; Research; Role; Site; T cell regulation; T-Cell Activation; T-Cell Proliferation; T-Lymphocyte; Technology; Th1 Cells; Th2 Cells; Therapeutic; Work; airway inflammation; allergic airway inflammation; allergic response; asthmatic patient; base; cell type; cytokine; effector T cell; in vivo; in vivo Model; insight; knock-down; novel; oral tolerance; overexpression; prevent; respiratory; response; screening; small hairpin RNA; ubiquitin-protein ligase; yeast two hybrid system

PROJECT SUMMARY/ABSTRACT The hallmark of allergic diseases is the infiltration/accumulation of Th2 cells at the sites of inflammation; however the mechanisms governing the development of unwanted Th2-driven airway diseases are poorly understood. Thus, today it is becoming clear that understanding the Th2-type immune responses and ways to control them may prove to be invaluable for the treatment of allergic inflammation. Recently, we as well as others, have demonstrated the role of E3 ubiquitin ligases in T cell tolerance. Cullin4A (Cul4A) belongs to the evolutionally conserved E3 ligase family and has been suggested to be involved in hematopoietic cell activation and in chromatin regulation; however, the role of Cul4A in T lymphocytes has not been addressed yet. Interestingly, expression of Cul4A was upregulated in tolerant T cells. Moreover, Cul4A knockout (KO) CD4+ T cells activated in vitro and in vivo under tolerogenic conditions exhibited an enhanced level of proliferation along with IL-2 and IL-4 production compared to wild-type cells, suggesting an important role of Cul4A in regulation of T cell tolerance. Strikingly, we found that Cul4A KO effector T cells and Treg cells expressed higher levels of Th2 but not Th1 and Th17 cytokines, which correlates with increased levels of IgG1 and IgE in the sera of Cul4A KO mice, indicating the selective role of Cul4A in controlling inflammatory Th2-type responses. Importantly, we detected reduced Cul4A expression in CD4+ T cells from asthmatic patients compared to CD4+ T cells from healthy donors, further indicating that Cul4A potentially contributes to airway immune tolerance induction. In addition, shRNA knockdown of Cul4A in human CD4+ T cells resulted in upregulated expression of Th2-specific cytokines. Based on these findings, we hypothesize that regulation of Th2-type immune responses by Cul4A may be an important checkpoint in airway tolerance induction, which is crucial to prevent development of allergic diseases. In Aim 1, we propose to determine the mechanisms whereby Cul4A controls T cell activation by utilizing gene knockdown approaches and in vitro and in vivo Th2 tolerance induction models. In Aim 2, we will determine the role of Cul4A in Th2 cell programming and its underlying mechanisms as well. We will employ cutting edge technologies, including two-hybrid screening and microarray analysis of gene expression, to identify the exact target(s) of Cul4A to determine its function in Th2 development. In addition, we will assess the cellular mechanisms whereby Cul4A controls Th2 type-driven allergic asthma. In Aim 3, we will determine the mechanism by which Cul4A regulates Treg function, particularly in controlling Th2 inflammatory responses. The physiological significance of this finding will be analyzed in different in vivo models. The proposed research will provide new significant insight into characterization of mechanisms underlying Cul4A-mediated Th2-type tolerance that may potentially have therapeutic implications for allergic diseases.

项目概要/摘要 过敏性疾病的标志是 Th2 细胞在炎症部位的浸润/积聚； 然而，Th2 驱动的气道疾病的控制机制尚不完善。 明白了。因此，今天越来越清楚的是，了解 Th2 型免疫反应和方法 控制它们可能对于治疗过敏性炎症具有无价的价值。 最近，我们和其他人证明了 E3 泛素连接酶在 T 细胞耐受中的作用。 Cullin4A (Cul4A) 属于进化上保守的 E3 连接酶家族，已被认为是 参与造血细胞活化和染色质调节；然而，Cul4A 在 T 中的作用 淋巴细胞尚未得到解决。有趣的是，Cul4A 的表达在耐受 T 细胞。此外，Cul4A 敲除 (KO) CD4+ T 细胞在体外和体内在耐受条件下被激活 与野生型细胞相比，其增殖水平以及 IL-2 和 IL-4 产量均有所提高， 表明 Cul4A 在调节 T 细胞耐受性中发挥重要作用。引人注目的是，我们发现 Cul4A KO 效应 T 细胞和 Treg 细胞表达较高水平的 Th2，但不表达 Th1 和 Th17 细胞因子，这与 Cul4A KO 小鼠血清中 IgG1 和 IgE 水平增加，表明 Cul4A 在 控制炎症 Th2 型反应。重要的是，我们检测到 CD4+ T 中 Cul4A 表达减少 将来自哮喘患者的细胞与来自健康捐赠者的 CD4+ T 细胞进行比较，进一步表明 Cul4A 可能有助于诱导气道免疫耐受。此外，Cul4A 的 shRNA 敲低 人类 CD4+ T 细胞导致 Th2 特异性细胞因子的表达上调。基于这些发现，我们 假设 Cul4A 对 Th2 型免疫反应的调节可能是一个重要的检查点 气道耐受诱导，这对于预防过敏性疾病的发展至关重要。 在目标 1 中，我们建议确定 Cul4A 通过利用来控制 T 细胞激活的机制 基因敲低方法以及体外和体内 Th2 耐受诱导模型。在目标 2 中，我们将 确定 Cul4A 在 Th2 细胞编程中的作用及其潜在机制。我们将聘用 尖端技术，包括双杂交筛选和基因表达微阵列分析， 确定 Cul4A 的确切靶标以确定其在 Th2 发育中的功能。此外，我们将评估 Cul4A 控制 Th2 型驱动的过敏性哮喘的细胞机制。在目标 3 中，我们将确定 Cul4A 调节 Treg 功能的机制，特别是控制 Th2 炎症 回应。这一发现的生理意义将在不同的体内模型中进行分析。 拟议的研究将为机制表征提供新的重要见解 潜在的 Cul4A 介导的 Th2 型耐受可能对以下疾病具有潜在的治疗意义 过敏性疾病。