Exploring the mechanism of ADAP1 control of HIV latency and reactivation in CD4 T cells

项目总结 从宿主基因组中消除整合的、具有复制能力的艾滋病毒前病毒 抑制性抗逆转录病毒疗法(ART)是功能性治愈的主要障碍。含有这些细胞的细胞 各种类型的前病毒产生边际水平的病毒产物，从而对免疫产生抵抗力 监视机制。这种缺乏免疫系统的检测，除了它的增长之外 由于动态平衡增殖和克隆性扩张，有可能延长潜伏感染细胞的寿命 形成了一个持久的储集层。人们对精准疗法的潜力抱有极大的热情 以临床环境中的潜在储集层为目标。为了实现这一重大的生物医学目标，我们必须首先发现 在我们可以之前，细胞内在和/或外在的储存库持久性和潜伏期再激活的“介体”切换 利用这些知识进行临床干预。为了开始填补这一知识空白，我们实施了一项收获- 在含有潜伏前病毒的CD4+T细胞系中进行功能筛选，并发现了几种新的调节因子 延迟重新激活开关。在这一探索性和发展性的R21赠款提案中，我们将专注于我们的 关注其中一种名为ADAP1的激活剂(Arf-GAP与双PH结构域包含蛋白-1)。 重要的是，ADAP1以前没有与免疫细胞生物学或艾滋病毒前病毒的控制有关 基因调控和潜伏期，因此我们的研究持有概念创新。 鉴于这些发现，本研究提案的主要目标是更好地理解 ADAP1控制HIV潜伏期和重新激活的分子机制。为了实现这一目标，我们 将在一套全面的CD4+T细胞效应器亚集中利用主要潜伏期模型的力量来 了解复杂和异质免疫细胞辅助因子与HIV前病毒基因组的相互作用 延迟和重新激活。这个提议的中心假设是ADAP1是激活细胞所必需的 CD4+T细胞亚群在静息状态下免疫时的信号转录调节程序 细胞刺激/共刺激。具体地说，我们将探索ADAP1是否能够重新激活潜伏的HIV 不同的CD4+T细胞亚群的潜伏期模型(目标1)，并询问ADAP1调节的细胞信号- 导致潜在艾滋病毒重新激活的转录程序(目标2)。这些研究可能会产生革命性的影响 影响我们对艾滋病毒潜伏期生物学的理解，并具有治疗意义。通过阐明如何 CD4+T细胞亚群决定感染过程，以及HIV如何利用宿主资源(如ADAP1) 延迟-重新激活开关，我们将深入了解基本流程以及可作为目标的途径 在治疗方面帮助实现NIAID结束艾滋病毒流行的使命。

PROJECT SUMMARY Elimination of integrated, replication-competent HIV proviruses from host genomes persisting despite suppressive anti-retroviral therapy (ART) is the major roadblock to a functional cure. Cells harboring these types of proviruses produce marginal levels of viral products thereby becoming refractory to immune surveillance mechanisms. This lack of detection by the immune system, in addition to its increased growth potential, due to homeostatic proliferation and clonal expansion, extend the lifespan of latently infected cells generating a persistent reservoir. There is enormous enthusiasm for the potential of precision therapies targeting the latent reservoir in clinical settings. To achieve this major biomedical goal, we must first discover cell-intrinsic and/or -extrinsic “mediators” of reservoir persistence and latency-reactivation switch before we can leverage this knowledge for clinical intervention. To start filling this gap in knowledge, we implemented a gain- of-function screen in a CD4+ T cell line containing a latent provirus and discovered several novel regulators of the latency-reactivation switch. In this exploratory and developmental R21 grant proposal, we will focus our attention on one of those activators named ADAP1 (Arf-GAP with dual PH domain-containing protein-1). Importantly, ADAP1 has not been previously linked to immune cell biology nor to the control of HIV proviral gene regulation and latency, thus our studies hold conceptual innovation. Given these findings, the major objective of this research proposal is to achieve a better understanding of the molecular mechanisms underlying ADAP1 control of HIV latency and reactivation. To accomplish this, we will leverage the power of primary models of latency in a comprehensive set of CD4+ T cell effector subsets to understand complex and heterogeneous immune cell co-factor–HIV proviral genome interactions during latency and reactivation. The central hypothesis of this proposal is that ADAP1 is required to activate cell signaling-transcription regulatory programs in CD4+ T cell subsets while resting cells are exposed to immune cell stimulation/co-stimulation. Specifically, we will explore if ADAP1 functions to reactivate latent HIV from latency models in various CD4+ T cell subsets (Aim 1), and interrogate the ADAP1-regulated cell signaling- transcriptional programs leading to latent HIV reactivation (Aim 2). These studies could have a revolutionary impact on our understanding of HIV latency biology and have therapeutic implications. By elucidating how CD4+ T cell subsets shape the course of infection and how HIV co-opts host resources (like ADAP1) for the latency-reactivation switch, we will gain insights into basic processes as well as pathways that can be targeted therapeutically to help achieve NIAID mission’s of ending the HIV epidemic.