Epigenetic Control of CD8 T-Cell Differentiation in Human Lymph Nodes

项目摘要 强效抗逆转录病毒疗法的发展，现在每天一次， 艾滋病病毒感染成为一种慢性病。目前，全球有超过1900万人正在接受终身治疗， 和治疗策略以及口服PrEP有能力进一步减少艾滋病毒传播。然而，在这方面， 尽管有这些显著的进展，但长期ART介导的血浆病毒载量抑制至无法检测， 水平并不能根除病毒，一旦治疗中断，病毒就会迅速反弹。许多后勤 为艾滋病毒感染者提供终身护理的局限性和成本挑战凸显了 在没有治疗的情况下控制病毒的新策略。新的数据表明，淋巴结 是ART期间HIV持续存在的主要来源，主要是因为受感染的T滤泡辅助细胞受到保护 由于从生殖中心（GC）部分排除细胞毒性CD8 T细胞（CTL）而免于免疫消除。的 调节CXCR5表达以允许CTL迁移到GC中的分子机制尚不清楚， 这主要是由于与获得用于这种研究的淋巴结样品相关的困难。通过创新 招聘策略，我们现在已经解决了这个问题。我们建议使用储存的淋巴结样本 从在血浆病毒血症发作时确定和治疗的人中获得，在许多情况下， 低于1，000 RNA拷贝/ml，以研究为什么CTL在很大程度上被排除在GC之外。我们的初步 ATAC-Seq研究表明，淋巴结CTL上的CXCR5表达受表观遗传学调控。遵循 基于这一观察，我们建议进行染色质可及性分析和转录谱分析， 分选HIV特异性CD8 T细胞以鉴定调节CXCR5表达的表观遗传机制。我们 实验方法将涉及成对染色质可及性和分类的滤泡细胞的转录分析。 和滤泡外HIV特异性CD8 T细胞。这一策略将有助于确定新的表观遗传和转录 这两个群体之间的差异。最后，我们将操纵一些不同的 使用外源性试剂，即细胞因子和表观遗传修饰药物， 诱导CD8 T细胞上CXCR5表达的最佳条件。我们的研究结果将导致新的战略， 将CTL重定向到需要它们杀死HIV感染细胞的滤泡区域。如果成功，我们的研究将 从而导致将CTL重定向至滤泡区域以根除HIV感染作为治疗策略一部分的新策略。

PROJECT SUMMARY The development of potent antiretroviral therapies, now delivered as a single pill once a day, has transformed HIV infection into a chronic disease. Globally, over 19 million people are now on life-long treatment, and test- and-treat strategies as was well as oral PrEP have the ability to further reduce HIV transmissions. However, despite these remarkable advances, prolonged ART mediated suppression of plasma viral loads to undetectable levels does not eradicate the virus, which rapidly rebounds upon treatment interruption. The many logistical limitations and cost challenges that come with providing life-long care to those living with HIV highlights the need for novel strategies of controlling the virus in the absence of therapy. Emerging data indicate that lymph nodes are a major source of HIV persistence during ART mainly because infected T follicular helper cells are protected from immune elimination due to partial exclusion of cytotoxic CD8 T cells (CTL) from germinal centers (GC). The molecular mechanisms that regulate CXCR5 expression which allows CTL migration into GCs are not known, mainly due to the difficulty associated with obtaining lymph node samples for such studies. Through innovative recruitment strategies, we have now solved this problem. We propose to use stored lymph node samples obtained from persons identified and treated at the onset of plasma viremia, in many when plasma viral loads are less than 1,000 RNA copies/ml to investigate why CTLs are largely excluded from GCs. Our preliminary ATAC-Seq studies suggest that CXCR5 expression on lymph node CTLs is epigenetically regulated. To follow up on this observation we propose to conduct chromatin accessibility analysis and transcriptional profiling of sorted HIV-specific CD8 T cells to identify epigenetic mechanisms that regulate CXCR5 expression. Our experimental approach will involve pairwise chromatin accessibility and transcription analysis of sorted follicular and extrafollicular HIV-specific CD8 T cells. This strategy will help to identify novel epigenetic and transcription factors that are different between the two populations. Finally, we will manipulate some of the differentially expressed genes using exogenous agents namely cytokines and epigenetic modifying drugs to determine the optimal conditions to induce CXCR5 expression on CD8 T cells. Our results will lead to novel strategies for redirecting CTL to follicular areas where they are needed to kill HIV infected cells. If successful, our studies will lead to novel strategies for redirecting CTL to follicular areas to eradicate HIV infection as part of a cure strategy.