IL-2 Family Cytokines and Receptors-- Mechanisms of Regulation & Action

IL-2 家族细胞因子和受体——调节机制

• 批准号: 8746596
• 负责人: Warren J Leonard
• 金额: $ 130.4万
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8746596
• 关键词: Adoptive Immunotherapy; Adoptive Transfer; Adult; Allergic; Apoptosis; Apoptosis Regulation Gene; Area; Autoimmune Process; B-Lymphocytes; Binding; Biological; Biological Process; Boxing; CD27 Antigens; CD4 Positive T Lymphocytes; CD8B1 gene; Cell Differentiation process; Cell physiology; Cells; ChIP-seq; Clinical; Colitis; Collaborations; Complex; Coupled; Cytokine Receptors; Cytokine Signaling; DNA Sequence Analysis; Defect; Dendritic Cells; Development; Disease; Elements; Event; Exhibits; Family; Galactosylceramides; Gene Expression; Gene Targeting; Genes; Genetic Transcription; Granulocyte-Macrophage Colony-Stimulating Factor; Helminths; Helper-Inducer T-Lymphocyte; Host Defense; Human; Human T-lymphotropic virus 1; IRF4 gene; Immune response; Immune system; Indium; Inflammatory; Inflammatory Bowel Diseases; Injection of therapeutic agent; Interferons; Interleukin 2 Receptor; Interleukin 2 Receptor Gamma; Interleukin-10; Interleukin-15; Interleukin-17; Interleukin-2; Interleukin-4; Interleukin-7; Interleukin-9; Leucine Zippers; MAPK Signaling Pathway Pathway; Malignant - descriptor; Malignant Neoplasms; Mediating; Molecular Profiling; Mus; Mutate; Natural Immunity; Normal Cell; PRDM1 gene; Phenotype; Population; Process; Production; Property; Proteins; Proto-Oncogene Proteins c-jun; Psoriasis; Regulation; Reporting; Response Elements; Role; STAT protein; STAT3 gene; STAT5A gene; STAT5B gene; Signal Transduction; Spinal Cord Diseases; System; T-Cell Activation; T-Cell Leukemia; T-Cell Lymphoma; T-Cell Receptor; T-Lymphocyte; T-bet protein; Th2 Cells; Time; Transcription Factor AP-1; Transgenic Mice; Transgenic Model; Tropical Spastic Paraparesis; Variant; Virus; X-Linked Severe Combined Immunodeficiency; base; cancer therapy; chromatin immunoprecipitation; cytokine; genome-wide; human disease; in vivo; insight; interleukin-12 receptor; killer T cell; neoplastic; neoplastic cell; novel; pathogen; prevent; protein expression; receptor; response; three dimensional structure; transcription factor; tumor

The interleukin-2 receptor and related cytokine/cytokine receptor systems are being studied to understand critical components of the T cell immune response in normal and neoplastic cells. Following T-cell activation, IL-2 and IL-2 receptors are induced; the magnitude and duration of the T-cell immune response is controlled by the amount of IL-2 produced, the levels of receptors expressed, and the time course of these events. Expression of IL-2Ra is interestingly high in cells infected with HTLV-I, the cause of adult T cell leukemia (ATL) and tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). Three chains of the IL-2 receptor exist, IL-2Ra, IL-2Rb, and gc, with IL-2Ra and IL-2Rb being significantly regulated at the level of transcription. gc is a shared chain also used by the receptors for IL-4, IL-7, IL-9, IL-15, and IL-21, and is the protein that is mutated in XSCID. We have focused primarily on the types of signals induced by some of these cytokines, particularly the activation of STAT proteins (signal transducers and activators of transcription), and the mechanism by which they regulate cytokine/STAT target genes. Given our prior observations that STAT5A or STAT5B transgenic mice develop tumors, which was consistent with STAT5 being implicated in malignant transformation and elevated in a range of human tumors, this is an important area for both normal and pathological states. Moreover, humans and mice with defective STAT protein expression have a range of immunological defects. In the past year, in a collaboration, we reported that enhanced T cell lymphoma in NOD-Stat5b transgenic mice is caused by hyperactivation of STAT5B in CD8+ T cells. T helper cell differentiation is critical for normal immune responses, with Th1 differentiation being important for host defense to viruses and other intracelllular pathogens, Th2 differentiation being vital in allergic disorders and related to helminths, and Th17 differentiation being vital in a range of inflammatory disorders, including psoriasis and inflammatory bowel disease. We previously showed that IL-2 is important for Th2 differentiation and reported that IL-2 regulates expression of the IL-4 receptor in a STAT5-dependent manner and critically controls priming of cells for Th2 differentiation. Moreover, using genome-wide Ilumina-based ChIP-Seq (chromatin immunoprecipitation coupled to DNA sequencing) analysis, we previously discovered broad regulation of Th2 differentiation via STAT5A and STAT5B, substantially extending earlier studies focused on STAT5A. Moreover, we had discovered that IL-2-mediated IL-4Ra induction was critical in priming cells for Th2 differentiation. In the prior year, we substantially extended these findings by showing that IL-2 via STAT5 induces expression of IL-12Rb1 and IL-12Rb2 and that the induction of IL-12Rb2 is critical for Th1 differentiation and we defined the mechanism of regulation of IL-12Rb2. Additionally, we showed that IL-2 via STAT5 also regulates the T box protein, T-bet. Interestingly, in contrast to the induction of IL-12R proteins, IL-2 inhibits expression of IL-6Ra and gp130, helping to explain the inhibition of Th17 differentiation. Consistent with the ability of Tbx21 to inhibit Th17 differentiation, expression of Tbx21 in Th17 cells resulted in increased IFNg but decreased expression of IL-17A. These results indicated a very broad effect of IL-2 via STAT5 on T helper cell differentation. In the current review year, we have continued to study the role of IL-2 in Th differentiation, including related to Th9 differentiation. During the past year, we also continued our collaboration with Dr. K. Christopher Garcia at Stanford, studying the actions of wild type IL-2 versus novel IL-2 variants, a project with potential clinical ramifications. These studies in part use the pmel-1 T cell receptor transgenic model of adoptive immunotherapy for cancer in collaboration with Dr. Nicholas Restifo, NCI. We have also collaborated with Dr. Garcia on a project in which the three dimensional structure of IL-2 complexed to its receptor was compared to that of IL-15 bound to its receptor. These studies, reported in the past year, have provided key mechanistic and structural insights into the functional differences between IL-2 and IL-15, which are highly related and share IL-2Rbeta and gc as receptor components but nevertheless possess distinctive biological functions. Although IL-2 primarily signals via cis-signaling and IL-15 via trans-signaling, these cytokines have essentially identical activation of STAT, PI3K/Akt, and Ras/MAPK signaling pathways. Moreover, gene expression profiles are very similar, although not identical. Thus, these cytokines have almost indistinguishable signaling properties despite different biological responses. This study has substantially elucidated structural and mechanistic aspects of IL-2 and IL-15 signaling. Previously, we demonstrated that IL-21 regulated expression of the Prdm1 gene that encodes BLIMP1 via a response element that depends on STAT3 and IRF4. This led to our reporting in the past year that in contrast to its known ability to cooperate with PU.1 in B cells to act via Ets-IRF composite elements (EICEs), IRF4 cooperates with BATF/JUN family proteins to act via AP1-IRF composite elements (AICEs) in T cells, as well as in B cells. We demonstrated critical cooperative regulation of important genes via these AICEs and demonstrated cooperative binding of IRF4, BATF, and JUN family proteins, with markedly diminished IRF4 binding in Batf-deficient cells and markedly diminished BATF binding in Irf4-deficient cells. We demonstrated critical regulation of key genes, including for example those encoding IL-10 and IL-17 via AICEs. In collaborative studies with Ken Murphy, we also reported that there were important compensatory roles for BATF factors in dendritic cell development mediated by BATF-IRF interactions involving the leucine zipper domain of BATF. We also reported key actions of cross-talk between IL-21/STAT3 and GM-CSF/STAT5. IL-21 has broad actions on T- and B-cells, but its actions in innate immunity are poorly understood. We reported that IL-21 induced apoptosis of conventional dendritic cells (cDCs) via STAT3 and Bim, and this was inhibited by granulocyte-macrophage colony-stimulating factor (GM-CSF). ChIP-Seq analysis revealed genome-wide binding competition between GM-CSF-induced STAT5 and IL-21-induced STAT3. Expression of IL-21 in vivo decreased cDC numbers, and this was prevented by GM-CSF. Moreover, repetitive α-galactosylceramide injection of mice induced IL-21 but decreased GM-CSF production by natural killer T (NKT) cells, correlating with decreased cDC numbers. Furthermore, adoptive-transfer of wild-type CD4+ T cells caused more severe colitis with increased DCs and interferon (IFN)-γ-producing CD4+ T cells in Il21r-/-Rag2-/- mice (which lack T cells and have IL-21-unresponsive DCs) than in Rag2-/- mice. Thus, IL-21 and GM-CSF exhibit cross-regulatory actions on gene regulation and apoptosis, regulating cDC numbers and thereby the magnitude of the immune response. Overall, the above findings enhance our understanding of mechanisms by which the gc family cytokines regulate gene expression and biologically important processes. In addition, these findings have implications related to the treatment of cancer, autoimmune, and other diseases.

正在研究白介素 2 受体和相关细胞因子/细胞因子受体系统，以了解正常和肿瘤细胞中 T 细胞免疫反应的关键组成部分。 T 细胞激活后，IL-2 和 IL-2 受体被诱导； T 细胞免疫反应的强度和持续时间由产生的 IL-2 量、表达的受体水平以及这些事件的时间进程控制。有趣的是，IL-2Ra 在感染 HTLV-I 的细胞中表达很高，HTLV-I 是成人 T 细胞白血病 (ATL) 和热带痉挛性截瘫/HTLV-I 相关脊髓病 (TSP/HAM) 的病因。 IL-2受体存在3条链：IL-2Ra、IL-2Rb和gc，其中IL-2Ra和IL-2Rb在转录水平上受到显着调节。 gc 是 IL-4、IL-7、IL-9、IL-15 和 IL-21 受体也使用的共享链，并且是 XSCID 中突变的蛋白质。我们主要关注其中一些细胞因子诱导的信号类型，特别是 STAT 蛋白（信号转导子和转录激活子）的激活，以及它们调节细胞因子/STAT 靶基因的机制。鉴于我们之前观察到 STAT5A 或 STAT5B 转基因小鼠会产生肿瘤，这与 STAT5 参与恶性转化并在一系列人类肿瘤中升高一致，这对于正常和病理状态都是一个重要领域。此外，STAT蛋白表达缺陷的人类和小鼠存在一系列免疫缺陷。去年，在一项合作中，我们报道了 NOD-Stat5b 转基因小鼠中增强的 T 细胞淋巴瘤是由 CD8+ T 细胞中 STAT5B 过度激活引起的。 T辅助细胞分化对于正常免疫反应至关重要，其中Th1分化对于宿主防御病毒和其他细胞内病原体很重要，Th2分化在过敏性疾病和与蠕虫相关的疾病中至关重要，而Th17分化在一系列炎症性疾病中至关重要，包括牛皮癣和炎症性肠病。我们之前表明IL-2对于Th2分化很重要，并报道IL-2以STAT5依赖性方式调节IL-4受体的表达，并关键控制细胞的Th2分化启动。此外，使用基于 Ilumina 的全基因组 ChIP-Seq（染色质免疫沉淀与 DNA 测序相结合）分析，我们之前发现通过 STAT5A 和 STAT5B 对 Th2 分化进行广泛调节，从而大大扩展了早期针对 STAT5A 的研究。此外，我们发现 IL-2 介导的 IL-4Ra 诱导对于启动细胞进行 Th2 分化至关重要。去年，我们进一步扩展了这些发现，表明 IL-2 通过 STAT5 诱导 IL-12Rb1 和 IL-12Rb2 的表达，并且 IL-12Rb2 的诱导对于 Th1 分化至关重要，并且我们定义了 IL-12Rb2 的调节机制。此外，我们还发现 IL-2 通过 STAT5 还可以调节 T 盒蛋白 T-bet。有趣的是，与IL-12R蛋白的诱导相反，IL-2抑制IL-6Ra和gp130的表达，有助于解释Th17分化的抑制。与 Tbx21 抑制 Th17 分化的能力一致，Th17 细胞中 Tbx21 的表达导致 IFNg 增加，但 IL-17A 表达减少。这些结果表明 IL-2 通过 STAT5 对 T 辅助细胞分化产生非常广泛的影响。 在当前的回顾年中，我们继续研究IL-2在Th分化中的作用，包括与Th9分化相关的作用。去年，我们还继续与斯坦福大学的 K. Christopher Garcia 博士合作，研究野生型 IL-2 与新型 IL-2 变体的作用，这是一个具有潜在临床影响的项目。这些研究部分使用了与 NCI 的 Nicholas Restifo 博士合作的癌症过继免疫疗法的 pmel-1 T 细胞受体转基因模型。我们还与 Garcia 博士合作开展了一个项目，其中将与其受体复合的 IL-2 的三维结构与与其受体结合的 IL-15 的三维结构进行比较。去年报道的这些研究为 IL-2 和 IL-15 之间的功能差异提供了关键的机制和结构见解，它们高度相关，并共享 IL-2Rbeta 和 gc 作为受体成分，但仍然具有独特的生物学功能。尽管 IL-2 主要通过顺式信号传导而 IL-15 主要通过反式信号传导发出信号，但这些细胞因子对 STAT、PI3K/Akt 和 Ras/MAPK 信号传导途径的激活作用基本相同。此外，基因表达谱虽然不相同，但非常相似。因此，尽管生物反应不同，但这些细胞因子具有几乎无法区分的信号传导特性。这项研究充分阐明了 IL-2 和 IL-15 信号传导的结构和机制。 之前，我们证明 IL-21 通过依赖于 STAT3 和 IRF4 的响应元件调节编码 BLIMP1 的 Prdm1 基因的表达。这导致我们在过去一年的报告中指出，与已知的与 B 细胞中的 PU.1 合作，通过 Ets-IRF 复合元件 (EICE) 发挥作用的能力相反，IRF4 与 BATF/JUN 家族蛋白合作，通过 T 细胞和 B 细胞中的 AP1-IRF 复合元件 (AICE) 发挥作用。我们证明了通过这些 AICE 对重要基因的关键协同调节，并证明了 IRF4、BATF 和 JUN 家族蛋白的协同结合，在 Batf 缺陷细胞中 IRF4 结合显着减少，在 Irf4 缺陷细胞中 BATF 结合显着减少。我们证明了关键基因的关键调控，包括通过 AICE 编码 IL-10 和 IL-17 的基因。在与 Ken Murphy 的合作研究中，我们还报道了 BATF 因子在涉及 BATF 亮氨酸拉链结构域的 BATF-IRF 相互作用介导的树突状细胞发育中具有重要的代偿作用。 我们还报告了 IL-21/STAT3 和 GM-CSF/STAT5 之间串扰的关键作用。 IL-21 对 T 细胞和 B 细胞具有广泛的作用，但其在先天免疫中的作用尚不清楚。我们报道，IL-21 通过 STAT3 和 Bim 诱导传统树突状细胞 (cDC) 凋亡，并且这种凋亡被粒细胞巨噬细胞集落刺激因子 (GM-CSF) 抑制。 ChIP-Seq 分析揭示了 GM-CSF 诱导的 STAT5 和 IL-21 诱导的 STAT3 之间存在全基因组结合竞争。 IL-21 体内表达减少了 cDC 数量，而 GM-CSF 可以阻止这种情况。此外，对小鼠重复注射 α-半乳糖神经酰胺可诱导 IL-21，但减少自然杀伤 T (NKT) 细胞产生 GM-CSF，这与 cDC 数量减少相关。此外，与 Rag2-/- 小鼠相比，野生型 CD4+ T 细胞的过继转移导致 Il21r-/-Rag2-/- 小鼠（缺乏 T 细胞且具有 IL-21 无反应 DC）中 DC 和产生干扰素 (IFN)-γ 的 CD4+ T 细胞增加，导致更严重的结肠炎。因此，IL-21和GM-CSF对基因调节和细胞凋亡表现出交叉调节作用，调节cDC数量，从而调节免疫反应的强度。 总的来说，上述发现增强了我们对 gc 家族细胞因子调节基因表达和生物学重要过程的机制的理解。此外，这些发现对癌症、自身免疫性疾病和其他疾病的治疗也有影响。