Th9 cells and protective TB immunity

Th9 细胞和保护性结核免疫

• 批准号: 10589125
• 负责人: Daniel F. Hoft
• 金额: $ 66.76万
• 依托单位: SAINT LOUIS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-09 至 2027-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10589125
• 关键词: Adoptive Transfer; Affect; Allergic Reaction; BCG Vaccine; Bacille Calmette-Guerin vaccination; Bacteria; Blood; Bronchoalveolar Lavage; CD4 Positive T Lymphocytes; Cell physiology; Cells; Coculture Techniques; Data; Development; Disease; Genes; Genetically Engineered Mouse; Growth; Helminths; Human; Immune; Immunity; Immunotherapy; Infection prevention; Inflammation; Inflammatory; Interferons; Interleukin-4; Interleukin-9; Intravenous; Knockout Mice; Lung; Macaca; Macrophage; Mediating; Memory; Messenger RNA; Monocyte Chemoattractant Proteins; Mucous Membrane; Mus; Mycobacterium tuberculosis; Oral; Parasites; Patients; Peripheral Blood Mononuclear Cell; Persons; Play; Production; Proteins; RNA-Binding Proteins; Rag1 Mouse; Recombinants; Reporter; Reporting; Role; Route; Sampling; Source; T-Cell Activation; Testing; Th1 Cells; Transforming Growth Factor beta; Transgenic Mice; Tuberculosis; Tuberculosis Vaccines; Tumor Immunity; Vaccinated; Vaccinee; Vaccines; cell type; cytokine; healthy volunteer; human subject; improved; in vivo; indicated prevention; mycobacterial; novel; novel therapeutics; novel vaccines; protective effect; response; transcriptome; tuberculosis immunity; vaccine-induced immunity

-γ-producing Th1 cells have been extensively studied for development of novel vaccines and therapeutics against Mycobacterium tuberculosis (Mtb) infection. However, recent studies demonstrate that Mtb-specific Th1 cells alone do not predict protection against tuberculosis (TB). Therefore, although Th1 cells are required for controlling Mtb replication, other types of immune cells may be needed to prevent infection and eradicate the bacteria. We recently found that a subset of IL-9-producing CD4+ T cells (Th9) can mediate protective immunity against Mtb infection. Th9 cells can be differentiated from naïve CD4+ T cells with TGF-β and IL-4, and play important roles in antitumor immunity and immunity related to allergic reactions. The role of Th9 cells in Mtb infection, however, remain largely unknown. We discovered a role for Th9 cells in TB immunity when we analyzed the transcriptomes in CD4+ T cells from healthy volunteers vaccinated with BCG and from people with latent TB infection (LTBI). IL-9 mRNA in CD4+ T cells topped the list of genes increased after BCG vaccination and LTBI. A significant increase in IL-9 production by bronchoalveolar lavage (BAL) cells after stimulation with infectious Mtb was observed only in LTBI patients and people vaccinated with oral (PO) BCG, indicating induction of Mtb-specific Th9 memory responses. To test whether Th9 cells mediate intracellular Mtb killing, we differentiated Mtb-specific Th9 cells from ESAT6-TCR transgenic mice and co-cultured these Th9 cells with Mtb-infected murine macrophages. Intracellular mycobacterial growth was significantly reduced in macrophages after interacting with Th9 cells. Moreover, neutralizing IL-9 abolished the inhibitory effects of Th9 cells, while addition of recombinant IL-9 alone inhibited intracellular bacterial growth. Furthermore, adoptive transfer of Mtb-specific Th9 cells into syngeneic RAG1/2-/- mice suppresses Mtb growth in vivo. In addition, we found that IL-9 was increased and Mtb growth decreased in mice deficient in MCPIP1, a new RNA-binding protein affecting T cell activation. Deletion of MCPIP1 in Th9 cells resulted in a significantly enhanced IL-9 production upon restimulation. Based on our preliminary findings, we hypothesize that Mtb-specific Th9 cells represent a distinct subset of CD4+ T cells important for protective TB immunity. Strategies inducing Mtb- specific Th9 cells could be used to develop more effective TB vaccines and/or immunotherapies. We propose three aims to test this novel hypothesis: Aim 1 to determine the effects of Mtb-specific Th9 cells on protective TB immunity; Aim 2 to define the roles of IL-9 in vaccine-induced protection against Mtb infection using genetically engineered mice, and Aim 3 to identify the source for IL-9 in PBMC and BAL cells from BCG vaccinated individuals, and the mechanisms of Mtb-specific Th9 cell-mediated bacterial killing in human macrophages. These studies will have a significant impact on improving our understanding of host protective immune mechanisms against Mtb infection, and provide the rationale for targeting Mtb-specific Th9 cells as a new strategy for more effective TB vaccines and/or immunotherapies against Mtb infection.

产生γ-γ的 Th1 细胞主要用于开发针对结核分枝杆菌 (Mtb) 感染的新型疫苗和疗法，然而，最近的研究表明，单独的 Mtb 特异性 Th1 细胞并不能预测对结核病 (TB) 的保护作用。 Th1 细胞是控制 Mtb 复制所必需的，可能需要其他类型的免疫细胞来预防感染和根除细菌。我们最近发现，产生 IL-9 的 CD4+ T 细胞的一个子集。 (Th9)可以介导针对Mtb感染的保护性免疫，Th9细胞可以从具有TGF-β和IL-4的幼稚CD4+T细胞中分化出来，并且在抗肿瘤免疫和过敏反应相关免疫中发挥重要作用。然而，当我们分析来自接受 BCG 的健康志愿者和潜伏性结核感染者的 CD4+ T 细胞转录组时，我们发现了 Th9 细胞在结核免疫中的作用。 (LTBI)。在 BCG 疫苗接种和 LTBI 后，CD4+ T 细胞中的 IL-9 mRNA 增加最多。仅在 LTBI 患者中观察到，支气管肺泡灌洗 (BAL) 细胞在受感染性 Mtb 刺激后产生的 IL-9 显着增加。和口服（PO）卡介苗治疗肺炎，表明诱导 Mtb 特异性 Th9 记忆反应 为了测试 Th9 细胞是否介导细胞内 Mtb 杀伤，我们分化了 Mtb 特异性 Th9 细胞。从 ESAT6-TCR 转基因小鼠中提取，并将这些 Th9 细胞与 Mtb 感染的小鼠巨噬细胞共培养，与 Th9 细胞相互作用后，巨噬细胞中的细胞内分枝杆菌生长显着减少，而中和 IL-9 消除了 Th9 细胞的抑制作用。重组 IL-9 单独抑制细胞内细菌生长，此外，Mtb 特异性 Th9 细胞过继转移至同基因中。 RAG1/2-/- 小鼠体内抑制 Mtb 生长 此外，我们发现在 MCPIP1 缺陷的小鼠中，IL-9 增加，Mtb 生长减少，MCPIP1 是一种影响 Th9 中 MCPIP1 缺失的新 RNA 结合蛋白。根据我们的初步研究结果，Mtb 特异性 Th9 细胞代表了对保护性结核免疫至关重要的 CD4+ T 细胞的独特子集。我们提出了三个目标来检验这一新假设： 目标 1 确定 Mtb 特异性 Th9 细胞对保护性结核免疫的影响；使用基因工程小鼠确定 IL-9 在疫苗诱导的 Mtb 感染保护中的作用，目标 3 确定来自 BCG 的 PBMC 和 BAL 细胞中 IL-9 的来源住院个体，以及人类巨噬细胞中 Mtb 特异性 Th9 细胞介导的细菌杀灭机制，这些研究将对提高我们对 Mtb 感染的宿主保护性免疫机制的理解产生重大影响，并为针对 Mtb 特异性 Th9 提供理论依据。细胞作为更有效的结核疫苗和/或针对结核分枝杆菌感染的免疫疗法的新策略。