M. tuberculosis strain-dependent interactions with host cells

结核病（TB）是一种多方面的疾病，其临床表现具有广泛的变化， 结核分枝杆菌是单一病原体感染的产物。广泛的遗传多样性， 人类和结核分枝杆菌基因组负责临床结果的差异， 宿主-病原体相互作用的改变是发病机制的关键。了解这些基础 异质性反应将揭示新的毒力和耐药性机制， 和诊断。不幸的是，研究感染的不同结果的机制的挑战 不仅包括鉴定宿主/病原体基因型与 人口，而且随后确定的机制，是病因的疾病， 需要在没有病原体自然宿主的实验室中进行研究。该计划需要 独特的优势，正在进行的全基因组关联研究（GWAS），已确定人类和 病原体变异与两个不同人群的异质性临床反应相关。 为了确定这些变化背后的机制，我们将采用一套强大的实验方法， 分析，包括新的基于蛋白质组学的扫描平台，以探测实验期间的宿主反应 巨噬细胞感染，这是正交于传统的mRNA谱，为了广泛地寻找变化， 宿主先天免疫途径与这些临床菌株相关的疾病结果相关。 根据我们的初步数据，我们假设许多这些相互作用发生在感染早期， 是由M.结核在这个建议中，我们主要关注相关性 在两组独特的临床细菌变体之间，与更大的 肺结核疾病和菌株更容易传播到身体的远端部位。一个 这两组菌株的一个意想不到的主题是ESX分泌的TB蛋白的流行 用M表示的系统。结核M.结核 细胞内生长和引发不同先天免疫应答所需的关键毒力决定因子 在巨噬细胞感染期间。一个核心假设是，影响疾病的细菌蛋白质组 结果富集了介导病原体和宿主之间相互作用的分泌蛋白 巨噬细胞为了验证这一假设，我们将与核心A和B合作，使用综合方法 联合收割机的基因数据，结核病GWAS数据集与遗传和蛋白质组学筛选，以确定 介导与巨噬细胞相互作用的致病基因。我们将使用同样的技术来合作 与项目2和3，以确定蛋白质/途径负责宿主抗性和细菌 传播。

Tuberculosis (TB) is a multifaceted disease that has extensive variation in clinical manifestations despite being the product of infection with a single pathogen, Mycobacterium tuberculosis. The extensive genetic diversity in human and Mycobacterium tuberculosis genomes responsible for differences in clinical outcomes represent modifications of host-pathogen interactions that are key to pathogenesis. Understanding the basis for these heterogenous responses will uncover new mechanisms of virulence and resistance and will impact treatment and diagnostics. Unfortunately, the challenges of studying the mechanisms of differential outcomes of infection in humans not only includes identification of correlations between host/pathogen genotypes with phenotypes in human populations, but also the subsequent identification of the mechanisms that are causal for disease which require studying them in the laboratory without the pathogen’s natural host organism. This Program takes advantage of unique, ongoing genome-wide association studies (GWAS) that have identified both human and pathogen variants that are associated with heterogenous clinical responses in two different human populations. To determine the mechanisms underlying these variations, we will employ a powerful set of experimental assays, including new proteomics-based scanning platform to probe host responses during experimental macrophage infection that is orthogonal to traditional mRNA profiling, in order to broadly search for changes in host innate immune pathways that correlate with disease outcomes associated with these clinical strains. Based on our preliminary data, we hypothesize that many of these interactions occur early during infection and are mediated by proteins secreted by M. tuberculosis. In this proposal, we focus primarily on correlations between two unique sets of clinical bacterial variants, strains that are associated greater transmission of pulmonary TB disease and strains that are more prone to dissemination to distal sites in the body. An unexpected theme from both of these sets of strains is the prevalence of TB proteins secreted by the ESX systems expressed in M. tuberculosis. Both the ESX-1 and ESX-5 secretion systems of M. tuberculosis are key virulence determinants required for intracellular growth and for eliciting distinct innate immune responses during macrophage infection. A central hypothesis is that the set of bacterial proteins that influence disease outcomes are enriched for secreted proteins that mediate interactions between pathogen and host macrophages. To test this hypothesis, we will collaborate with Cores A and B to use an integrative approach to combine genetic data from the M. tuberculosis GWAS datasets with genetic and proteomic screen to identify causal genes that mediate interactions with macrophages. We will use these same technologies to collaborate with Projects 2 and 3 to identify proteins/pathways responsible for host resistance and bacterial dissemination.