CD8 T cell suppression of HIV latency establishment and maintenance in virally suppressed individuals

CD8 T 细胞抑制病毒抑制个体中 HIV 潜伏期的建立和维持

基本信息

批准号：
10242771
负责人：
Deanna A Kulpa
金额：
$ 39万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-09-24 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10242771
关键词：
Address Animals Antiviral Agents CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes CD8B1 gene Cells Clinical Clinical Research Cytotoxic T-Lymphocytes DNA Modification Process Disease Epigenetic Process Excision Flow Cytometry Future Gene Expression Genetic Transcription Goals HIV HIV Infections Histone Deacetylation In Vitro Individual Infection Interleukin-15 Interruption Intervention Laboratories Lead Longevity Lymphocyte Suppression Macaca Maintenance Mediating Methylation Modeling Molecular Outcome Phenotype Play Predisposition Production Role SIV Series Shock T-Lymphocyte Subsets Testing Therapeutic Transcript Viral Viral reservoir Viremia Virus Virus Replication Work antiretroviral therapy base combinatorial cytokine design effective intervention experimental study high dimensionality histone methylation improved in vitro Model in vivo innovation novel novel strategies transcription factor viral rebound viral rescue

项目摘要

ABSTRACT: Current antiretroviral therapy (ART) does not eradicate HIV as shown by the rapid rebound of viremia upon treatment interruption. Rescuing viral gene expression in latently infected cells by compounds termed Latency Reversing Agents (LRA) is a strategy to reduce the virus reservoir in ART-treated HIV-infected individuals (i.e., shock & kill). HIV latency is triggered by mechanisms that lead to the silencing of virus expression including epigenetic DNA modification through histone methylation and deacetylation, limited availability of critical transcription factors and inefficient elongation of the nascent viral transcripts. Recent studies in ART-treated SIV- infected macaques demonstrated that depletion of CD8+ lymphocytes is followed by reactivation of virus production, and increased susceptibility to the LRA effect of the IL-15 superagonist ALT803. These results strongly suggest that CD8+ lymphocyte play an important yet understudied role in silencing HIV expression. In this proposal, we hypothesize that CD8+ T cells suppress HIV gene expression by promoting the establishment and maintenance of HIV latency, and that reversal of this effect may result in a significant amplification of the LRA effect of various compounds, thus impacting the reservoir size and stability in vivo. We will use innovative approaches to identify the CD8+ T cell mediated mechanisms of HIV silencing. In Aim 1, we will employ a novel model of HIV latency to characterize the role of CD8+ T cells in the establishment of HIV latency. We will quantify HIV gene expression in CD4+ T cell subsets and characterize the impact of CD8+ T cells on HIV latency establishment. In Aim 2, we will characterize the role of CD8+ T cells in the maintenance of HIV latency. Our in vitro model will allow us to define how CD8+ T cells maintain HIV latency during cytokine driven activation, proliferation or differentiation. In Aim 3, we will design a combinatorial anti-latency strategy that will eliminate most if not all latently infected cells. We will employ high dimensional flow cytometry to define alterations in phenotype associated with suppression and activation of latency reversal. Ultimately, we will characterize the role of CD8+ lymphocyte in counter-acting the latency reversal by specific LRAs (and LRA combinations) as a key step to develop effective interventions in which viral transcription in latently infected cells is rescued to reduce the reservoir size. The experiments described in this proposal will identify novel mechanisms of HIV silencing that can lead to the reactivation and subsequent elimination of most (if not all) latently infected cells. We propose that this overarching goal can be achieved through a step-wise scientific approach that includes in vitro and ex vivo studies that will address a newly-defined mechanism of HIV persistence. We believe that the work proposed in this application will allow us to understand the mechanisms by which CD8+ lymphocytes suppress virus transcription and ultimately promote HIV latency and persistence in ART-treated HIV-infected individuals, thus helping designing new approaches for HIV eradication.

抽象的：目前的抗逆转录病毒疗法（ART）并不能根除艾滋病毒，病毒血症在治疗后迅速反弹就表明了这一点。治疗中断。通过称为潜伏期的化合物来拯救潜伏感染细胞中的病毒基因表达逆转剂 (LRA) 是一种减少接受 ART 治疗的 HIV 感染者（即，震惊并杀死）。 HIV潜伏期是由导致病毒表达沉默的机制触发的，包括通过组蛋白甲基化和脱乙酰化进行表观遗传 DNA 修饰，关键的可用性有限转录因子和新生病毒转录物的低效延伸。 ART 治疗的 SIV 的最新研究受感染的猕猴证明 CD8+ 淋巴细胞耗尽后病毒重新激活产生，并增加对 IL-15 超级激动剂 ALT803 的 LRA 效应的敏感性。这些结果强烈表明 CD8+ 淋巴细胞在沉默 HIV 表达方面发挥着重要但尚未充分研究的作用。在这个提议中，我们假设 CD8+ T 细胞通过促进 HIV 基因的表达来抑制 HIV 基因的表达。 HIV 潜伏期的建立和维持，并且这种效应的逆转可能会导致显着的放大各种化合物的 LRA 效应，从而影响体内储库的大小和稳定性。我们将使用创新方法来确定 CD8+ T 细胞介导的 HIV 沉默机制。在目标 1 中，我们将采用一种新的 HIV 潜伏期模型来表征 CD8+ T 细胞在 HIV 建立中的作用延迟。我们将量化 CD4+ T 细胞亚群中的 HIV 基因表达，并表征 CD8+ T 细胞的影响细胞对HIV潜伏期的建立。在目标 2 中，我们将描述 CD8+ T 细胞在维持艾滋病毒潜伏期。我们的体外模型将使我们能够定义 CD8+ T 细胞如何在细胞因子作用期间维持 HIV 潜伏期驱动激活、增殖或分化。在目标 3 中，我们将设计一种组合抗延迟策略，将消除大部分（如果不是全部）潜伏感染细胞。我们将采用高维流式细胞术来定义与潜伏期逆转的抑制和激活相关的表型改变。最终，我们将描述 CD8+ 淋巴细胞在对抗特定 LRA（和 LRA）潜伏期逆转中的作用组合）作为制定有效干预措施的关键步骤，其中潜伏感染细胞中的病毒转录被抢救以缩小水库规模。本提案中描述的实验将确定新的机制 HIV 沉默可导致大多数（如果不是全部）潜伏感染者重新激活并随后消除细胞。我们建议，这一总体目标可以通过逐步的科学方法来实现，包括体外和离体研究，将解决新定义的艾滋病毒持久性机制。我们相信本申请中提出的工作将使我们能够了解 CD8+ 的机制淋巴细胞抑制病毒转录并最终促进接受 ART 治疗的 HIV 潜伏期和持久性艾滋病毒感染者，从而帮助设计根除艾滋病毒的新方法。