Dissecting the molecular regulation of T cell localization and function within the Mycobacterium tuberculosis granuloma

剖析结核分枝杆菌肉芽肿内 T 细胞定位和功能的分子调控

基本信息

批准号：
10550190
负责人：
Benjamin Henry Gern
金额：
$ 18.65万
依托单位：
SEATTLE CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-13 至 2026-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10550190
关键词：
Ablation Address Affect Antibiotic Therapy Antibiotics Antigens Autopsy Award BCG Live BLR1 gene Biological Assay CCR CCR6 gene CD4 Positive T Lymphocytes CXCR3 gene Career Mobility Cells Cellular Immunity Cessation of life Clinical Development Development Plans Diffuse Disease Outcome Dose Exhibits Flow Cytometry Future Genetic Genetic Transcription Goals Granuloma Homing Human Image Imaging Device Immune Immune response Immunity Immunization Immunology Immunosuppression In Situ Individual Infection Infiltration Investigation Knock-out Knockout Mice Knowledge Laboratories Learning Lung Lung infections Lymphocyte Macrophage Macrophage Activation Manuscripts Microbe Microscopy Modeling Molecular Mus Mycobacterium tuberculosis Outcome Pathogenesis Pathway interactions Patients Physicians Physiological Play Research Resources Role Scientist Shapes Signal Transduction Site Structure of parenchyma of lung T cell regulation T-Cell Activation T-Lymphocyte Techniques Testing Tissues Training Transforming Growth Factor beta Tuberculosis Vaccination Vaccine Design advanced analytics career career development cell type chemokine receptor conditional knockout effector T cell experimental study global health improved in vivo innovation lung pathogen mouse model novel novel therapeutics novel vaccines pulmonary granuloma receptor response single cell analysis tertiary lymphoid organ trafficking transcriptomics treatment strategy tuberculosis granuloma tuberculosis immunity tuberculosis treatment

项目摘要

PROJECT SUMMARY/ABSTRACT Mycobacterium tuberculosis (Mtb) infection is a major global health problem. Despite widespread immunization with Bacillus Calmette–Guérin and availability of antibiotic therapy, there are 10 million new cases and 1.4 million deaths annually, underscoring the need for improved treatment strategies. CD4 T cell-mediated immunity is critical for protection against Mtb infection, and is governed by 1) appropriate trafficking of CD4 T cells to distinct compartments within the Mtb-infected lung, including sites of infection, and 2) robust effector function at these sites. We have uncovered a spatially-resolved immunosuppressive mechanism by which localized TGFβ signal plays a dominant role in limiting the presence and function of T effector cells within the granuloma, with the greatest effect directly adjacent to infected cells. We have shown that ablation of T cell TGFβR-signaling reverses this suppression and results in reduced bacterial burdens. Here we propose to dissect the mechanistic underpinnings of these observations and address the central hypothesis that: Inappropriate localization of CD4 T cells, in combination with pleiotropic inhibition by localized TGFβ activation within the granuloma core limits effective immunity to Mtb pulmonary infection. To address this hypothesis, we will use a tractable yet physiologic murine ultra-low dose model of Mtb infection and advanced analytical microscopy, then confirm concepts learned in mice in human pulmonary granulomas as follows: 1) We will comprehensively characterize how individual chemokine receptors contribute to CD4 T cell localization, activation, function and ultimately, infection outcome. These findings will be corroborated in human granulomas. 2) We will also characterize how TGFβ activation by individual cell types limits localized CD4 T cell activation, function and infection outcome. This will be validated in granulomas from patients who die from active TB and those with asymptomatic Mtb infection who die from other causes, an unparalleled resource in the antibiotic era. These studies will also yield information about additional inhibitory pathways that are present within pulmonary granuloma and provide a framework for their characterization which can be pursued in future R01 applications. Thus, this proposal will leverage the strengths of our ULD Mtb mouse model and innovative imaging tools to understand how T cells traffic to infected sites and characterize a dominant immunosuppressive factor within this space, which has important implications for vaccine design and host-directed therapy. Dr. Gern’s career development plan builds on a background of using advanced imaging to study pulmonary pathogens with coursework and hands-on training in advanced immunology, Mtb pathogenesis, advanced microscopy, and laboratory management. A K08 award will allow Dr. Gern to make maximal use of SCRI and UW’s extensive scientific resources to achieve scientific independence, advancing his career goal to understand the factors dictating immune cell trafficking and function within different tissue microenvironments during Mtb infection, with the ultimate goal of improving tuberculosis treatment.

项目摘要/摘要结核分枝杆菌（MTB）感染是主要的全球健康问题。尽管免疫宽度伴有Calmette -Guérin的芽孢杆菌和抗生素疗法的可用性，有1000万例新病例和140万例每年死亡，强调需要改善治疗策略的需求。 CD4 T细胞介导的免疫是对于防止MTB感染至关重要，并由1）适当地运输CD4 T细胞到不同的 MTB感染的肺部内部的隔室，包括感染部位，2）在这些肺部的功能可靠站点。我们发现了一种空间分辨的免疫抑制机制，该机制通过该机制进行定位在限制颗粒瘤内T效应细胞的存在和功能方面起着主要作用，直接对感染细胞的最大效果。我们已经表明，T细胞TGFβR信号逆转的消融这种抑制作用并导致细菌伯良的降低。在这里，我们建议剖析机械这些观察结果的基础，并解决了以下中心假设：CD4的不当定位 T细胞，结合粒状核心核心限制内局部TGFβ激活的多效性抑制有效免疫MTB肺部感染。为了解决这一假设，我们将使用可处理但生理的 MTB感染和晚期分析显微镜的鼠超低剂量模型，然后确认了学到的概念在人类肺肉芽肿的小鼠中，如下所示：1）我们将全面表征个体趋化因子受体有助于CD4 T细胞定位，激活，功能以及最终感染结果。这些发现将在人类颗粒中得到证实。 2）我们还将表征TGFβ如何通过单个细胞类型限制了局部的CD4 T细胞激活，功能和感染结果。这将被验证在死于活跃结核病患者的肉芽肿和无症状MTB感染的患者中其他原因是抗生素时代无与伦比的资源。这些研究还将产生有关的信息肺肉芽肿内存在的其他抑制途径，并为其提供框架可以在未来的R01应用中进行的表征。那，该提议将利用优势我们的ULD MTB鼠标模型和创新成像工具，以了解T细胞如何流动到感染的站点和表征该空间内主要的免疫抑制因素，这对疫苗设计和宿主指导的治疗。 Gern博士的职业发展计划以使用的背景为基础先进的成像，用于研究肺病病原体，并在高级培训中进行动手培训免疫学，MTB发病机理，晚期显微镜和实验室管理。 K08奖将允许博士 Gern最大程度地利用SCRI和UW的广泛科学资源来实现科学独立性，推进他的职业目标，以了解决定免疫细胞贩运和功能在不同的因素 MTB感染过程中组织微环境，其最终目的是改善结核病治疗。