Live Imaging of Immunity to M. tuberculosis

结核分枝杆菌免疫实时成像

• 批准号: 10326395
• 负责人: Joel D. Ernst
• 金额: $ 10.1万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-06 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10326395
• 关键词: Antigen Presentation; Antigens; Bacteria; C57BL/6 Mouse; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; California; Cell Communication; Cells; Chronic; Communicable Diseases; Development; Distant; Effectiveness; Environment; Event; Failure; Frequencies; Goals; Granuloma; HIV; Human; Image; Immune; Immunity; Infection; Knowledge; Light; Lung; Lymphocyte; Lymphocyte antigen; Lymphoid Cell; Mechanics; Medicine; Modeling; Molecular; Mus; Mycobacterium tuberculosis; Myeloid Cells; Nature; Peptide/MHC Complex; Phenotype; Play; Positioning Attribute; Reagent; Reporter; Research; Role; San Francisco; Signal Transduction; Site; Structure of parenchyma of lung; System; T cell response; T-Cell Development; T-Lymphocyte; Testing; Tissues; Tuberculosis; Tuberculosis Vaccines; Universities; Up-Regulation; Vaccines; Work; adaptive immune response; antigen-specific T cells; biosafety level 3 facility; chemokine receptor; chronic infection; design; experimental study; follow-up; immune checkpoint; in vivo; innovation; insight; intravital imaging; intravital microscopy; migration; multiphoton microscopy; nonhuman primate; pathogen; predictive modeling; receptor expression; receptor function; response; tool; tuberculosis immunity; vaccine trial; Antigen Presentation; Antigens; Bacteria; C57BL/6 Mouse; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; California; Cell Communication; Cells; Chronic; Communicable Diseases; Development; Distant; Effectiveness; Environment; Event; Failure; Frequencies; Goals; Granuloma; HIV; Human; Image; Immune; Immunity; Infection; Knowledge; Light; Lung; Lymphocyte; Lymphocyte antigen; Lymphoid Cell; Mechanics; Medicine; Modeling; Molecular; Mus; Mycobacterium tuberculosis; Myeloid Cells; Nature; Peptide/MHC Complex; Phenotype; Play; Positioning Attribute; Reagent; Reporter; Research; Role; San Francisco; Signal Transduction; Site; Structure of parenchyma of lung; System; T cell response; T-Cell Development; T-Lymphocyte; Testing; Tissues; Tuberculosis; Tuberculosis Vaccines; Universities; Up-Regulation; Vaccines; Work; adaptive immune response; antigen-specific T cells; biosafety level 3 facility; chemokine receptor; chronic infection; design; experimental study; follow-up; immune checkpoint; in vivo; innovation; insight; intravital imaging; intravital microscopy; migration; multiphoton microscopy; nonhuman primate; pathogen; predictive modeling; receptor expression; receptor function; response; tool; tuberculosis immunity; vaccine trial

Project Summary Tuberculosis (TB), caused by the bacterium, Mycobacterium tuberculosis, kills more humans every year than does any other infectious disease, including HIV. Among the obstacles to eliminating TB is the lack of a sufficiently-efficacious vaccine. Despite strong evidence for essential roles of CD4 T cells in TB immunity, naturally-occurring T cell responses do not reliably eliminate the pathogen in TB, and we do not fully understand the mechanisms that limit the effectiveness of CD4 T cell responses to M. tuberculosis. In earlier work, we discovered that for optimal immune control, CD4 T cells must directly recognize and make intermolecular contacts with M. tuberculosis-infected cells at the site of infection in the lungs. In light of this requirement for intimate contact, we and others have found (in mice, nonhuman primates, and humans) that CD4 T cells are located at the periphery of granulomas, rather than in the core where infected cells reside. We therefore hypothesize that a major mechanism limiting immunity to TB is the failure of CD4 T cells to contact and engage with infected cells, and that overcoming this failure will increase the efficacy of T cell immunity to TB. Several potential mechanisms can explain the spatial separation of M. tuberculosis-infected cells and CD4 T cells in vivo, yet these are not amenable to analysis using fixed, static images or cells removed from the granuloma environment. Therefore, in this project, we propose to combine a unique multiphoton microscopy system for intravital imaging, contained in a Biosafety Level 3 facility at the IPBS in Toulouse, with unique reporter mice and M. tuberculosis strains developed and characterized at UCSF, to characterize interactions of antigen-specific CD4 T cells with M. tuberculosis-infected and bystander cells in the lungs of live mice. The combination of these innovative experimental systems allows us to test specific hypotheses that can account for the spatial and functional separation of CD4 T cells and M. tuberculosis-infected cells in the lungs. The knowledge gained from these studies will be used: 1) to inform design of experiments to define the molecular mechanisms that restrict CD4 T cell interactions with M. tuberculosis-infected cells in vivo; 2) to provide the basis for studies comparing distinct candidate TB vaccines, to determine which of them promote development of T cells that optimally access M. tuberculosis-infected cells in granuloma cores. In additional experiments, we will extend recent findings indicating important roles for innate lymphoid cells (ILC) in protective immunity to TB. Specifically, we will follow up on findings that type 2 ILC (ILC2) undergo dramatic phenotypic transformations to ILC1-like cells in vivo in response to M. tuberculosis infection, by live imaging of the interactions of ILC2 and ILC1-like cells with M. tuberculosis-infected cells and with CD4 T cells, during the initial and the chronic stages of infection. Our studies have high potential to provide valuable insights and new paradigms of immunity to TB, with the goal of informing development of efficacious vaccines and host-directed therapies.

项目摘要 由细菌，结核分枝杆菌引起的结核病（结核病）每年杀死人类多于 是否有其他传染病，包括艾滋病毒。消除结核病的障碍之一是缺乏 足够有效的疫苗。尽管有充分的证据表明CD4 T细胞在结核病免疫中的基本作用，但 自然出现的T细胞反应不能可靠地消除结核病的病原体，我们不完全理解 限制CD4 T细胞对结核分枝杆菌的有效性的机制。在较早的工作中，我们 发现为了获得最佳免疫控制，CD4 T细胞必须直接识别并使分子间 与肺部感染部位的结核分枝杆菌感染细胞接触。鉴于这一要求 亲密接触，我们和其他人发现（在小鼠，非人类灵长类动物和人类中）CD4 T细胞是 位于颗粒的周围，而不是在感染细胞的核心中。因此，我们 假设限制对结核病免疫的主要机制是CD4 T细胞接触和参与的失败 随着感染的细胞，克服这种失败将增加T细胞免疫对TB的疗效。一些 潜在的机制可以解释结核分枝杆菌感染细胞的空间分离和体内CD4 T细胞的空间分离， 然而，使用固定的，静态图像或从颗粒瘤中去除的静态图像或细胞不适合分析 环境。因此，在这个项目中，我们建议将独特的多光子显微镜系统结合起来 在图卢兹的IPB的生物安全3级设施中包含的插入成像，带有独特的记者小鼠和 M.在UCSF开发和表征结核病菌株，以表征抗原特异性的相互作用 活小鼠肺中的结核病分枝杆菌和旁观细胞的CD4 T细胞。这些的结合 创新的实验系统使我们能够测试可以说明空间和的特定假设 肺中CD4 T细胞和结核病感染细胞的功能分离。从中获得的知识 将使用这些研究：1）为实验设计提供了限制分子机制的设计 CD4 T细胞与结核分枝杆菌感染的细胞体内相互作用； 2）为研究提供基础 不同的候选结核病疫苗，以确定其中哪些促进了最佳访问的T细胞的开发 肉芽肿核中的结核病感染细胞。在其他实验中，我们将扩展最新发现 表明先天淋巴样细胞（ILC）对TB的保护性免疫的重要作用。具体来说，我们将遵循 关于2型ILC（ILC2）的发现，在体内对ILC1样细胞进行了戏剧性的表型转化 通过实时成像ILC2和ILC1样细胞与M. 在初始和慢性感染期间，感染结核病的细胞和CD4 T细胞。我们的研究 具有很高的潜力，可以提供宝贵的见解和对结核病免疫的新范式，目的是告知 开发有效的疫苗和宿主指导的疗法。