Role of RhCMV in shaping the SIV proviral landscape

项目概要/摘要 治愈HIV-1感染的主要障碍是由静息记忆CD 4 T细胞组成的储库，其基因组 含有可诱导和可复制的HIV-1前病毒。水库的衰减是缓慢的， 抗逆转录病毒疗法（ART）。越来越清楚的是，维持HIV-1持续存在的主要机制 在ART期间，潜伏感染的记忆性CD 4 T细胞的生理性增殖。感染的CD 4 T细胞可以增殖 而不产生病毒，其结果将导致子细胞携带扩增的HIV-1前病毒克隆， 相同序列和宿主整合位点。然而，在这种情况下，不同前病毒克隆之间的扩增速率是 不平等。在某些个体中，30%以上的前病毒样本可能属于高度克隆的群体 扩增，这是一种与通过抗原相遇的克隆增殖一致的机制。建立特定的联系 然而，抗原的种类和它们在多大程度上独立地导致HIV的持续存在是一个尚未解决的问题。 巨细胞病毒（CMV）是一种潜伏性β疱疹病毒，在免疫活性宿主中无症状， 刺激记忆T细胞库。艾滋病毒感染者几乎普遍合并感染巨细胞病毒。本课题 我组建了一个多学科的研究小组，直接评估慢性抗原刺激 CMV（i）促进记忆性CD 4 T细胞池的增殖（ii）有助于HIV-1的克隆多样性和大小。 1水库在ART和（iii）影响时间病毒复发时，ART中断。具体来说，我们将 利用ART治疗的SIV感染恒河猴的成熟模型，通过双重检测来研究这些问题。 approach.第一个将利用无病原体的恒河猴CMV（RhCMV）-幼稚恒河猴（RM）的可用性， 比较存在或不存在CMV时SIV储库动力学。第二部分将评估SIV持续性的措施 当CMV复制被抗病毒药物西多福韦阻断时。对我们的目标至关重要的是， 在多个纵向时间点，在多个组织中，用几种检测方法询问SIV前病毒DNA， SIV储层的定量和定性方面。我们认为，全面、高度协同、 我们提出的严格控制的研究将（i）确定一个促进记忆转换的免疫显性靶点 ART期间的CD 4 T细胞，并通过扩展，HIV-1储库的持久性，以及（ii）提供了使用最近的 耐受性良好的FDA批准的CMV抗病毒药物作为加速HIV-1清除的手段。

Project Summary/Abstract The main obstacle to curing HIV-1 infection is a reservoir that consists of resting memory CD4 T cells whose genomes contain inducible and replication-competent HIV-1 proviruses. Decay of the reservoir is slow and requires lifelong antiretroviral therapy (ART). It has become increasingly clear that the predominant mechanism sustaining HIV-1 persistence during ART is the physiologic proliferation of latent-infected memory CD4 T cells. Infected CD4 T cells can proliferate without producing virus, the result of which will lead to daughter cells harboring expanded HIV-1 proviral clones that share identical sequence and host integration sites. The rate of expansion among distinct proviral clones in this setting however is not equal. In some individuals, upwards of 30% of proviruses sampled can belong to populations that are highly clonally expanded, a mechanism consistent with clonal proliferation by antigen encounter. Establishing a link between particular antigens and the degree to which they independently contribute to HIV persistence, however, is an unresolved question. Cytomegalovirus (CMV) is a latent betaherpesvirus that while asymptomatic in immunocompetent hosts, persistently stimulates the memory T cell pool. Persons living with HIV are near universally coinfected with CMV. In this project, we have assembled a multidisciplinary team of investigators to directly assess the degree to which chronic antigenic stimulation by CMV (i) promotes proliferation of the memory CD4 T cell pool (ii) contributes to clonal diversity and size of the HIV- 1 reservoir during ART and (iii) impacts the time to viral recrudescence when ART is interrupted. Specifically, we will utilize the well-established model of ART-treated SIV-infected rhesus macaques to examine these questions by a dual approach. The first will exploit availability of pathogen-free, rhesus CMV (RhCMV)-naïve rhesus macaques (RMs) to compare SIV reservoir dynamics in the presence or absence of CMV. The second will assess measures of SIV persistence when CMV replication is blocked pharmacologically with antiviral Cidofovir. Critical to our aims are that we will interrogate SIV proviral DNA at multiple longitudinal timepoints, in multiple tissues, and with several assays that inform both quantitative and qualitative aspects of the SIV reservoir. We believe that the comprehensive, highly synergistic, and rigorously controlled studies we propose will (i) identify an immunodominant target that promotes turnover of memory CD4 T cells during ART and by extension, persistence of the HIV-1 reservoir and (ii) provide a rationale to employ recent well-tolerated FDA-approved CMV antivirals as a means to accelerate HIV-1 clearance.