Deciphering Mechanisms of HIV Latency Reversal in Perinatal Infections

潜伏的艾滋病毒使全世界近3700万艾滋病毒感染者无法治愈，其中170万人是 孩子消除潜伏储库（LR）对于无抗逆转录病毒治疗（ART）缓解至关重要， 停止抗逆转录病毒疗法时不会发生病毒反弹。潜伏期逆转剂（LRA）可以治疗靶向 LR并使其易于消除。LRA在成人中的临床试验正在进行中，并计划于 围产期感染的儿童然而，至关重要的是，我们最近的体外研究表明， 当LR在婴儿期建立（通过围产期感染）时，逆转较慢且幅度较低 与成年期相比。我们的研究结果表明，这种主要的治疗方法需要进一步的研究。 体内研究，以解释围产期感染中HIV潜伏期逆转的机制，以指导临床 在这个人群中进行LRA试验。我们假设LR建立的免疫环境 并且存在于围产期感染中使其本质上比成人感染更耐潜伏逆转。 本申请的具体目的是：1）确定和比较的大小，组成， 在围产期和成人感染中诱导潜伏的HIV储库，并描述其差异; 2)通过CD 4+转录组学分析确定前病毒再激活易感性的相关性 T细胞在围产期和成人感染中的作用; 3）确定调节性T细胞（T细胞）对 围产期HIV感染中的潜伏HIV库，并探索单细胞RNA-seq方法的实用性 检测CD 4 + T细胞亚群对潜伏期逆转的不同反应。我们将在围产期招募艾滋病毒感染者- 受感染的儿童，青少年和成人在美国和乌干达照顾，并全面表征 并比较潜伏库的大小，如通过总的和完整的前病毒DNA（包括前病毒DNA的位点）测量的。 整合）。我们将确定在最大T细胞活化条件下对潜伏期逆转的敏感性， 临床相关的潜伏期逆转治疗剂（TLR-7激动剂GS-9620、IL-15超激动剂N-803或 SMAC模拟物-AZD 5582），并且当按感染模式、LRA分类、病毒学持续时间 抑制、前病毒载量和亚型。免疫激活的基线状态之间的相关性，沿着 CD 4 + T细胞的基线转录组作为感染方式、地理区域/HIV亚型的函数，以及 将确定诱导水库的大小。我们将进一步研究TdR和非TdR对 围产期感染中的LR，以及单细胞RNA-seq在定义基线转录水平中的探索性研究 不同的CD 4+记忆T细胞亚群，包括T细胞亚群，以及它们对T细胞亚群的不同反应， LRAS。这里提出的系统表征将为围产期HIV潜伏期的机制性见解提供信息， 包括调节性T细胞（TCRs）的贡献，并提供关于LRA在围产期应用的关键数据。 感染，沿着用于测量LRA在该群体中的功效的最佳生物标志物。

Latent HIV prevents cure for the nearly 37 million persons living with HIV worldwide, of whom 1.7 million are children. Elimination of the latent reservoir (LR) is critical for antiretroviral therapy (ART)-free remission, where viral rebound does not occur when ART is stopped. Latency reversal agents (LRAs) can therapeutically target the LR and render it susceptible to elimination. Clinical trials of LRAs in adults are ongoing and planned for perinatally-infected children. Critically, however, our recent in vitro studies reveal that the kinetics of latency reversal are slower and of lower magnitude when the LR is established in infancy (through perinatal infection) compared with during adulthood. Our findings suggest that this major therapeutic approach requires further ex vivo studies to decipher mechanisms of HIV latency reversal in perinatal infections in order to guide clinical trials of LRAs in this population. We hypothesize that the immune environment in which the LR is established and exists in perinatal infection renders it intrinsically more resistant to latency reversal than in adult infection. The specific aims of this application are: 1) Determine and compare the size, composition, and inducibility of the latent HIV reservoir in perinatal and adult infection, and characterize their differences; 2) Identify correlates of susceptibility to proviral reactivation through transcriptomic analyses of CD4+ T cells in perinatal and adult infections; and 3) Define the contribution of regulatory T cells (Tregs) to the latent HIV reservoir in perinatal HIV infection and explore the utility of single-cell RNA-seq approaches to examine differential responses of CD4+ T cell subsets to latency reversal. We will enroll perinatally HIV- infected children, adolescents, and adults cared for in the US and Uganda, and comprehensively characterize and compare the size of the latent reservoir, as measured by total and intact proviral DNA (including sites of integration). We will determine susceptibility to latency reversal under maximum T cell activating conditions and clinically relevant latency reversal therapeutics (TLR-7 agonist GS-9620, the IL-15 superagonist N-803, or the SMAC mimetic-AZD5582), and when analyzed by mode of infection, LRA class, duration of virologic suppression, proviral load, and subtype. Correlations between baseline states of immune activation, along with baseline transcriptomes of CD4+ T cells as a function of mode of infection, geographic region/HIV subtype, and size of the induced reservoir will be determined. We will further examine contribution of Tregs and non-Tregs to the LR in perinatal infections, with exploratory studies of single-cell RNA-seq in defining baseline transcriptional profiles of the different CD4+ memory T cell subsets, including Tregs, and their differential responses to the LRAS. The systematic characterization proposed here will inform mechanistic insights into perinatal HIV latency, including the contribution of regulatory T cells (Tregs), and provide critical data on the utility of LRAs in perinatal infections, along with optimal biomarkers for measuring efficacy of LRAs in this population.