HIV Infection and Latency In Astrocytes

HIV 感染和星形胶质细胞潜伏期

• 批准号: 10129115
• 负责人: Johnny J He
• 金额: $ 57.57万
• 依托单位: ROSALIND FRANKLIN UNIV OF MEDICINE & SCI
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10129115
• 关键词: HIV; Infection; Latency; Astrocytes

ABSTRACT Combination antiretroviral therapy (cART) has considerably prolonged the lifespan of HIV-infected individuals and changed the landscape of the HIV/AIDS disease. However, latent HIV in the cells/tissues has prevented from achieving a functional cure or complete eradication. Limited access to cART and the ability of HIV to establish latent infection have made the central nervous system (CNS) unique HIV reservoirs. Microglia/macrophages are the main target cells for HIV infection in the CNS and all can be productively, latently or persistently infected. In contrast, astrocytes are infected but in a restricted manner; our understanding of these cells as HIV latent reservoirs and their roles of HIV latency in HIV/neuroAIDS is quite limited. We have recently found that cell-cell contact leads to successful HIV infection of astrocytes and establishment of HIV latency in these cells with an extremely low level of ongoing HIV replication. In addition, we have found that expression of HIV early gene Tat in astrocytes induces miR-132 and down-modulates methyl CpG-binding protein 2 (MeCP2), a chromatin-remodeling epigenetic factor and causes neurotoxicity through miRNA- containing exosomes. Moreover, we have shown that cocaine activates HIV replication in HIV latently infected astrocytes through miR-132 expression and that Tat expression is linked to establishment of HIV latency in astrocytes. Lastly, we have obtained the preliminary data that miR-132 expression in the cerebrospinal fluid (CSF) is elevated in HIV-infected subjects with minor cognitive and motor disorder. As a logical extension of our published and preliminary studies, we propose to characterize HIV infection and latency in astrocytes and their contribution to astrocyte function and HIV/neuroAIDS in the era of cART. The underlying hypothesis of this proposal is that HIV-infected astrocytes constitute latent HIV reservoirs in the CNS and directly contribute to HIV/neuroAIDS. To test this hypothesis, we propose to address the following four interrelated specific aims: (1) To characterize cell-cell contact-mediated HIV infection of astrocytes; (2) To elucidate molecular mechanisms of HIV latency in astrocytes; (3) To determine effects of latent HIV infection on astrocytes and neurons; and (4) To identify CSF biomarkers for HIV latency in the brain. We will use a combined molecular, cellular, biochemical, and genetic approach including use of primary mouse cortical astrocyte cultures and neuron cultures, doxycycline-inducible brain-specific HIV Tat transgenic mice (iTat), primary human fetal brain/astrocyte cultures, brain tissues and CSF samples of HIV-1 cohorts in our studies. We anticipate that this proposal will allow us to determine the regulatory mechanisms of HIV latency in astrocytes and the significance of these cells as HIV reservoirs in the ear of cART and in the context of cocaine abuse. The findings will likely inform control and eradication strategies for the HIV reservoirs in the CNS. The enormous amount of information available on HIV infection and pathogenesis in the CNS/astrocytes and HIV latency in the periphery and the results obtained from our preliminary studies make accomplishment of these aims practical.

抽象的 联合抗逆转录病毒疗法 (cART) 显着延长了 HIV 感染者的寿命，并且 改变了艾滋病毒/艾滋病的现状。然而，细胞/组织中潜伏的艾滋病毒阻碍了实现 功能性治愈或完全根除。 cART 的获取机会有限以及 HIV 建立潜伏感染的能力 使中枢神经系统（CNS）成为独特的艾滋病毒储存库。小胶质细胞/巨噬细胞是HIV的主要靶细胞 中枢神经系统感染，所有人都可能被有效、潜伏或持续感染。相反，星形胶质细胞被感染，但 以有限的方式；我们对这些细胞作为 HIV 潜伏库的理解以及它们在 HIV 潜伏期中的作用 艾滋病毒/神经艾滋病是相当有限的。我们最近发现，细胞与细胞的接触导致艾滋病毒成功感染 星形胶质细胞和这些细胞中艾滋病毒潜伏期的建立，以及极低水平的持续艾滋病毒复制。在 此外，我们发现星形胶质细胞中HIV早期基因Tat的表达诱导miR-132并下调甲基化 CpG 结合蛋白 2 (MeCP2)，一种染色质重塑表观遗传因子，通过 miRNA 引起神经毒性 含有外泌体。此外，我们还发现可卡因可激活 HIV 潜伏感染星形胶质细胞中的 HIV 复制 通过 miR-132 表达，Tat 表达与星形胶质细胞中 HIV 潜伏期的建立有关。最后，我们 获得HIV感染者脑脊液（CSF）中miR-132表达升高的初步数据 患有轻微认知和运动障碍的受试者。作为我们已发表的和初步研究的逻辑延伸，我们 提议描述星形胶质细胞中艾滋病毒感染和潜伏期的特征及其对星形胶质细胞功能的贡献 cART 时代的艾滋病毒/神经艾滋病。该提议的基本假设是，感染艾滋病毒的星形胶质细胞构成 中枢神经系统中存在潜在的艾滋病病毒储存库，并直接导致艾滋病毒/神经艾滋病。为了检验这个假设，我们建议 解决以下四个相互关联的具体目标：（1）表征细胞间接触介导的 HIV 感染 星形胶质细胞； (2) 阐明星形胶质细胞中HIV潜伏的分子机制； (3) 确定潜在HIV的影响 星形胶质细胞和神经元感染； (4) 确定大脑中 HIV 潜伏期的 CSF 生物标志物。我们将使用一个 结合分子、细胞、生化和遗传方法，包括使用原代小鼠皮质星形胶质细胞 培养物和神经元培养物、强力霉素诱导的脑特异性 HIV Tat 转基因小鼠 (iTat)、原代人类胎儿 我们研究中的 HIV-1 群体的脑/星形胶质细胞培养物、脑组织和脑脊液样本。我们预计该提案 将使我们能够确定星形胶质细胞中艾滋病毒潜伏期的调节机制以及这些细胞作为 cART 耳内和可卡因滥用情况下的 HIV 储存库。研究结果可能会为控制和 中枢神经系统中艾滋病毒储存库的根除策略。有关艾滋病毒感染的大量信息 中枢神经系统/星形胶质细胞的发病机制和外周的艾滋病毒潜伏期以及我们初步获得的结果 研究使这些目标的实现变得切实可行。