Longitudinal Analysis of Immune Signatures (IMS) of M. tuberculosis-specific T cells

项目概要：项目2 肺结核（TB）是由结核分枝杆菌（Mtb）感染引起的，是一种主要的结核病。 全球范围内单一传染源导致的死亡在这里，我们将表征免疫签名（IMS）的 Mtb抗原特异性CD 4 T细胞在不同状态的Mtb感染和BCG疫苗接种的个体中。 具体而言，我们将利用我们建立的Mtb肽表位库和测定系统来鉴定抗原- 特异性CD 4 T细胞及其T细胞受体（TCR）。IMS将在细胞计数中进一步表征， 抗原刺激后和离体的单细胞RNA-seq测定。对于目标1，我们将招募一批个人， 患有活动性结核病（ATB），其特征是不受控制的症状性Mtb感染， 抗结核治疗我们将在治疗过程中纵向跟踪IMS，并确定标记物 预测治疗结果。对于目标2，我们将招募患有“潜伏性”结核感染（LTBI）的个体， 特征在于对Mtb的免疫反应性，但没有疾病症状（即Mtb反应性）。LTBI是 异质性，包括成功清除感染并显示 记忆免疫反应，以及其他亚临床感染的风险增加， 疾病目前还没有检测方法可以区分亚临床感染和清除感染。我们将确定 IMS在LTBI纵向治疗中的作用，并确定谁表现出最大的治疗反应 与ATB相似，我们认为最有可能患有亚临床疾病。对于单独的LTBI队列， 我们将利用一种独特的人类攻击模型，从以下组织中获得具有抗原特异性驻留T细胞的样品： 肺，并使用它们来评价血液与肺中IMS之间的重叠和差异， 一组个人。对于目标3，我们将在成人接种卡介苗（再接种）前后采集样本， 表征疫苗诱导的IMS。未感染结核分枝杆菌的成年人的再接种已被证明是保护性的 因此，将该IMS与LTBI（受控感染）vs. ATB（不受控感染）进行比较 可以揭示疫苗诱导免疫的保护性成分。

Project Summary: Project 2 Pulmonary tuberculosis (TB) is caused by infection with Mycobacterium tuberculosis (Mtb) and is a leading cause of death from a single infectious agent worldwide. Here we will characterize immune signatures (IMS) of Mtb antigen-specific CD4 T cells in individuals with different states of Mtb infection and BCG vaccination. Specifically, we will utilize our established Mtb peptide epitope pools and assay systems to identify antigen- specific CD4 T cells and their T cell receptors (TCRs). The IMS will be further characterized in cytometry and single-cell RNA-seq assays after antigen stimulation and ex vivo. For Aim 1, we will enroll cohorts of individuals with active tuberculosis (ATB), characterized by uncontrolled symptomatic Mtb infection, who will be receiving anti-TB therapy. We will longitudinally track the IMS over the course of treatment, and identify markers predictive of treatment outcomes. For Aim 2, we will enroll individuals with ‘latent’ TB infection (LTBI), which is characterized by immune reactivity to Mtb but no symptoms of disease (i.e. Mtb reactive). LTBI is heterogeneous, consisting both of individuals who have successfully cleared their infection and display a memory immune response, as well as others with subclinical infection at increased risk of developing active disease. There is currently no test available to distinguish subclinical from cleared infection. We will determine the IMS in prophylactically-treated LTBI longitudinally, and determine who displays a treatment response most similar to ATB, which we consider most likely to have had subclinical disease. For a separate cohort of LTBI, we will utilize a unique human challenge model to obtain samples with antigen-specific resident T cells from the lung and use them to evaluate overlap and differences between the IMS in the blood vs. lung from the same set of individuals. For Aim 3, we will obtain samples taken pre- and post-BCG (re)vaccination in adults to characterize the vaccine induced IMS. Revaccination of Mtb uninfected adults has been shown to be protective from disease, thus, comparing this IMS with that in LTBI (controlled infection) vs. ATB (uncontrolled infection) can reveal protective components of vaccine induced immunity.