Parenchymal and airway CD4+ T cells in protection against pulmonary tuberculosis

实质和气道 CD4 T 细胞预防肺结核

• 批准号: 10683702
• 负责人: RICHARD F SILVER
• 金额: --
• 依托单位: LOUIS STOKES CLEVELAND VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10683702
• 关键词: Address; Adoptive Cell Transfers; Adoptive Transfer; Animal Model; Antibodies; Antigens; Area; Barbering; Blood Circulation; Blood Vessels; Bronchoalveolar Lavage; Bronchoscopy; CD4 Positive T Lymphocytes; CXCR3 gene; Cells; Child Development; Communication; Complex; Containment; Development; Evaluation; Exposure to; Genus Mycobacterium; Goals; Health; Homing; Human; Immune; Immune response; Immunity; Immunology procedure; Individual; Infection; Inhalation; Injections; Interferon Type II; International; Intravenous; Label; Laboratories; Leukocytes; Ligands; Lung; Lymphocyte; Mediating; Memory; Methodology; Military Personnel; Modeling; Modification; Mus; Mycobacterium Infections; Mycobacterium bovis; Mycobacterium tuberculosis; National Institute of Allergy and Infectious Disease; Nature; Organism; Persons; Phenotype; Population; Prevalence; Proteins; Public Health; Pulmonary Tuberculosis; Research; Research Personnel; Respiratory Tract Infections; Risk; Sampling; Silver; Site; Stains; Structure of parenchyma of lung; Surface; T memory cell; T-Lymphocyte; Tail; Tissues; Tuberculosis; Tuberculosis Vaccines; Vaccination; Vaccines; Veins; Veterans; Virulent; Work; antigen challenge; base; chemokine; experience; insight; intravenous injection; memory CD4 T lymphocyte; mouse model; novel; novel strategies; particle; prevent; recruit; respiratory; respiratory challenge; respiratory pathogen; response; study population; tuberculin purified protein derivative; vaccination against tuberculosis; vaccine-induced immunity

Tuberculosis (TB) remains a significant international public health threat, particularly for US military personnel who are often deployed to areas of high TB prevalence. Mycobacterium tuberculosis (Mtb) is a respiratory pathogen spread via inhalation of infectious airborne particles. Most infected individuals develop protective immunity that serves to contain the organism, but approximately 10% will eventually develop active TB. The localization of mycobacteria-specific CD4+ T cells to the lung appears to be critical to protection against Mtb infection, and may not be optimized by current TB vaccination with intradermal (ID) M. bovis BCG. Human studies using lung cells obtainable by bronchoalveolar lavage (BAL) provide a means to assess local immune responses to Mtb that may be uniquely relevant to evaluating novel TB vaccines. The distinct nature of local immunity within the lung has been further emphasized by recent murine studies demonstrating that respiratory infection is followed by the development of CD4+ memory T cells that are localized to the lung parenchyma and do not rejoin the general circulation. These tissue-resident memory T cells (TRM) display a distinct phenotype, and also show increased capacity to protect against respiratory infection with Mtb. The use of intravenous (IV) injection of pan-leukocyte antibodies to identify T cells that are not in communication with the vasculature has provided a means to sort pulmonary TRM from vascular-associated memory cells. This intriguing approach has not yet been applied to clarifying the significance of BAL-based studies of immunity to Mtb; this step is critical, however, to the ultimate application of these insights to human studies. The overall goal of the current proposal is to clarify the mechanisms by which CD4+ T cells within BAL differ from and interact with other lung CD4+ T-cell populations to mediate lymphocyte recruitment to the lung and, ultimately, protection against respiratory challenge with Mtb. Our research team is uniquely qualified to address these issues, as it includes investigators with experience in bronchoscopy-based studies of human immunity to Mtb (Richard Silver, PI), murine assessments of immunity to Mtb (W. Henry Boom, Consultant) and optimization of immune assays involving lung cells from both mice and humans (Tracey Bonfield, Co-investigator). We will also greatly benefit from the involvement of a pioneer in the application of TRM methodology to the study of Mtb infection (Daniel Barber of NIAID, Consultant). Our studies will utilize a murine model of Mtb infection in which lung homogenate cells stained by IV injection (“IV+ T cells”) associated with the lung vasculature are sorted from T cells that cannot be labeled in this manner. These “IV- T cells” predominantly display a TRM phenotype and are retained within the parenchyma. We will apply this approach to evaluate the interactions of IV- and IV+ lung CD4+ T cells and to clarify their relationship to BAL CD4+ T cells in mice. Parallel human studies will utilize both baseline BAL cells and unique samples obtained by modeling recall responses to Mtb protein antigens using bronchoscopic segmental antigen challenge with purified protein derivative of Mtb (PPD). These approaches will be integrated to address the following Specific Aims: 1) To determine the mechanisms by which mycobacteria-specific CD4+ T cells in BAL are phenotypically distinct from IV- and IV+ lung homogenate CD4+ T-cell populations; 2) To determine the mechanisms by which BAL CD4+ T-cells interact with IV- and IV+ CD4+ lung T-cell populations to recruit additional T cells to the lung parenchyma and airways; 3) To determine the mechanisms by which BAL and lung parenchymal CD4+ T cells interact to mediate protection against respiratory infection with virulent M. tuberculosis.

结核病（TB）仍然是一个重大的国际公共卫生威胁，特别是对美国军事人员 他们经常被部署到结核病高发地区。结核分枝杆菌（Mtb）是一种呼吸道结核病。 病原体通过吸入空气中的传染性颗粒而传播。大多数受感染的人会产生保护性 免疫力，以遏制有机体，但大约10%的人最终会发展为活动性结核病。 分枝杆菌特异性CD 4 + T细胞在肺中的定位似乎对预防结核病至关重要。 Mtb感染，并且可能无法通过当前皮内（ID）M的TB疫苗接种来优化。牛卡介苗人类 使用通过支气管肺泡灌洗（BAL）获得的肺细胞的研究提供了评估局部免疫的方法， 对结核分枝杆菌的反应，可能是唯一相关的评估新的结核疫苗。地方的独特性质 最近的鼠类研究进一步强调了肺内的免疫， 感染之后是局限于肺实质的CD 4+记忆T细胞的发育 不要再进入大气循环这些组织驻留记忆T细胞（TRM）显示出独特的 表型，并且还显示增加的保护免受Mtb的呼吸道感染的能力。使用 静脉内（IV）注射泛白细胞抗体以鉴定不与白细胞通讯的T细胞。 血管系统提供了一种从血管相关记忆细胞中分选肺TRM的方法。这 有趣的方法尚未应用于澄清基于BAL的免疫研究的意义， 然而，这一步对于将这些见解最终应用于人类研究至关重要。 目前的建议的总体目标是阐明BAL中CD 4 + T细胞的作用机制。 与其他肺CD 4 + T细胞群不同并相互作用，以介导淋巴细胞募集， 肺，并最终保护免受Mtb的呼吸挑战。我们的研究团队是独一无二的 有资格解决这些问题，因为它包括具有支气管镜研究经验的研究者 人对Mtb免疫力的评估（Richard银，PI），鼠对Mtb免疫力的评估（W.亨利嘣， 顾问）和优化涉及来自小鼠和人的肺细胞的免疫测定（Tracey Bonfield，Co-investigator）。我们也将大大受益于一个先驱的参与，在应用 结核分枝杆菌感染研究的TRM方法（NIAID的丹尼尔巴伯，顾问）。我们的研究将利用 Mtb感染的鼠模型，其中通过IV注射染色的肺匀浆细胞（“IV+ T细胞”） 与肺脉管系统一起从不能以这种方式标记的T细胞中分选出来。这些“IV型T细胞” 主要显示TRM表型并保留在薄壁组织内。我们将把这种方法应用于 评价IV-和IV+肺CD 4 + T细胞的相互作用，并阐明其与BAL CD 4 + T细胞的关系 对小鼠平行人体研究将使用基线BAL细胞和通过建模获得的独特样本 使用纯化蛋白进行的支气管镜节段抗原激发对Mtb蛋白抗原的回忆应答 Mtb的衍生物（PPD）。这些方法将综合起来，以实现以下具体目标： 1)确定BAL中分枝杆菌特异性CD 4 + T细胞表型改变的机制， 与IV-和IV+肺匀浆CD 4 + T细胞群不同; 2)确定BAL CD 4 + T细胞与IV-和IV+ CD 4+肺T细胞相互作用的机制， 群体以将额外的T细胞募集到肺实质和气道; 3)确定BAL和肺实质CD 4 + T细胞相互作用介导 对呼吸道感染的保护作用。结核