Human Genetic Dissection of Exit from Latency in Tuberculosis

只有少数潜伏感染结核分枝杆菌(Mtb)的人(~5%)会患上结核病 由于休眠的分枝杆菌重新激活而引起的疾病，通常是肺结核病(PTB)。有越来越多的 遗传流行病学证据表明，肺结核在人类中具有很强的遗传成分，但分子水平 结核分枝杆菌重新激活的易感性基础在很大程度上仍不清楚。候选基因和全基因组(GW) 协会研究表明，常见的变异在肺结核的遗传学中只起到很小的作用，或者 他们的角色仅限于特定的子组。我们最近通过一种无偏见的GW链接方法表明， 与T细胞和NK细胞发育有关的TOX基因的常见变体与肺结核有关 在两个种族不同的人群中，潜伏期较短的年轻患者。其他遗传因素 而TOX也可能导致肺结核，包括未知基因的罕见变异。我们的项目将结合一个 重点深入剖析TOX在肺结核中的作用，基于人类和小鼠的研究，具有GW 研究罕见变异在肺结核中的作用的方法。将在海地招募研究对象，通过 盖斯基奥中心，以建立一个大的病例/对照样本(艾滋病毒阴性和艾滋病毒阳性)，并以家庭为基础 样本中至少有两个受肺结核影响的兄弟姐妹。我们将进行全面的关联研究 与TOX基因多态相关的肺结核，以及基于组合的GW对肺结核患者罕见变异的搜索 GW连锁和全外显子组测序研究。所有变种都被一致发现与 结核病将通过尖端技术在分子和细胞水平上进行免疫学验证。我们 我将研究之前发现的位于TOX 3‘区域的变体对T细胞的功能影响 在人体细胞体外和在小鼠体内的免疫。将使用小鼠模型来研究这一角色 小鼠T细胞对结核分枝杆菌感染应答中TOX的检测及内源性T细胞应答分析 伴有T细胞特异性TOX基因缺失。我们的初步数据表明，TOX在 人CD4T细胞、Treg细胞、NK细胞和γδT细胞以及小鼠的CD4T细胞和Treg细胞，并且TOX的3‘端可能 有监管活动，进一步支持TOX作为结核病免疫的主要调节者的候选资格。

Only a minority of individuals with latent Mycobacterium tuberculosis (Mtb) infection (~5%) develop TB disease, typically pulmonary TB (PTB), due to the reactivation of dormant mycobacteria. There is growing genetic epidemiological evidence that PTB has a strong genetic component in humans, but the molecular basis of susceptibility to Mtb reactivation remains largely unknown. Candidate gene and genome-wide (GW) association studies have suggested that common variants play only a modest role in the genetics of PTB, or that their role is restricted to specific subgroups. We recently showed, by an unbiased GW linkage approach, that common variants of TOX, a gene involved in T-cell and NK-cell development, are associated with PTB in young patients with a short latency duration, in two ethnically different populations. Genetic factors other than TOX may also contribute to PTB, including rare variants of unknown genes. Our project will combine a focused in-depth dissection of the role of TOX in PTB, based on both human and mouse studies, with a GW approach investigating the role of rare variants in PTB. Study subjects will be recruited in Haiti, through the GHESKIO Center, to establish a large case/control sample (HIV-negative and HIV-positive), and a family-based sample with at least two PTB-affected siblings. We will conduct a comprehensive association study of PTB with TOX polymorphisms, and a GW search for rare variants in PTB patients, based on a combination of GW linkage and whole-exome sequencing studies. All variants consistently found to be associated with PTB will be validated immunologically, at the molecular and cellular levels with cutting-edge techniques. We will study the functional impact of previously identified variants located in the 3' region of TOX on T-cell immunity, both in vitro in human cells, and in vivo in mice. Mouse models will be used to investigate the role of TOX in T-cell responses to Mtb infection, together with analyses of endogenous T-cell responses in mice with T cell-specific TOX gene deletion. Our preliminary data indicate that TOX is strongly expressed in human CD4, Treg, NK, and γδT cells and in murine CD4 and Treg cells, and that the 3' end of TOX probably has regulatory activities, further supporting the candidacy of TOX as a prime regulator of PTB immunity.