NeuroAIDS Therapy in the EcoHIV Mouse Model

描述(由申请人提供)：针对HIV-1感染的高效抗逆转录病毒疗法(HAART)有效地降低了全身病毒负担，并改善了大多数依从性患者的免疫功能。然而，与HIV-1相关的痴呆症和其他神经系统疾病仍然存在。长寿巨噬细胞和脑细胞中的病毒库对HAART不敏感，大脑无法使用某些药物。这项应用旨在通过实验研究抗病毒药物对HIV-1在脑内复制和发病机制的影响，使用EcoHIV/NDK嵌合病毒建立免疫活性小鼠HIV-1感染的新模型。该病毒编码HIV-1的所有蛋白，但gp120除外，因此对HAART药物保持敏感性。我们最近报道了扎西他滨和阿巴卡韦阻断了EcoHIV/NDK在小鼠体内的感染，并在这一应用中表明奈韦拉平和蛋白酶抑制剂萨奎那韦显著减少了病毒在小鼠体内的传播。在我们的模型中，通过获取大量受感染的动物并使用实时荧光聚合酶链式反应监测多个组织中的病毒，可以定量测试药物疗效，并通过分析细胞转录产物、脑细胞功能障碍。在这一发展计划中，我们建议1)测试抗逆转录病毒药物预防EcoHIV/NDK对成年和幼年小鼠急性周围和中枢神经系统感染的有效性；2)测试抗逆转录病毒药物对减少幼鼠周围组织和脑内已建立的EcoHIV/NDK感染和相应的神经发病的有效性。淋巴细胞、巨噬细胞和大脑中的病毒载量和脑细胞基因表达的激活将通过实时荧光聚合酶链式反应来确定，小胶质细胞的激活将通过免疫细胞化学来评估。该计划直接调查难以进入大脑的药物是否可以防止神经系统内HIV-1和脑部疾病的储存，驻留在大脑中的病毒是否对HAART药物敏感，以及对正在进行的病毒复制的抑制在多大程度上耗尽了脑细胞、巨噬细胞和骨髓中的病毒储存并改善了脑部疾病。这一发展计划是为了指导未来在这一动物模型中的翻译研究，以筛选或开发新的药物来预防HIV-1相关的神经发病。公共卫生相关性HIV-1感染导致免疫缺陷，通常还会导致神经系统疾病，导致记忆力减退、精神错乱和行动失控。这一应用程序建议使用实验中感染艾滋病毒-1的小鼠和目前用于人类的抗病毒药物来确定它们是否能阻止小鼠大脑中的感染和疾病。此外，该应用程序还将测试感染后给老鼠服用的药物是否真的能消除大脑中的病毒，从而有望实现抗病毒药物控制感染人类神经系统疾病的能力。

DESCRIPTION (provided by applicant): Highly active antiretroviral therapy (HAART) for HIV-1 infection effectively reduces systemic virus burden and improves immune function in most compliant patients. Nevertheless, HIV-1-associated dementia and other nervous system disorders persist. Viral reservoirs in long-lived macrophages and brain cells are not sensitive to HAART and the brain is inaccessible to certain drugs. This application is designed to investigate the effects of antiviral drugs on HIV-1 replication and pathogenesis in the brain experimentally using a new model of HIV-1 infection of immunocompetent mice by the chimeric virus, EcoHIV/NDK. This virus encodes all the proteins of HIV-1, except gp120, and thus preserves sensitivity to HAART agents. We recently reported that zalcitabine and abacavir block EcoHIV/NDK infection of mice and show in this application that nevirapine and the protease inhibitor saquinavir significantly reduce virus spread in mice. Access to a large number of infected animals and monitoring of virus in multiple tissues using real-time PCR permit quantitative test of drug efficacy, and through assay of cellular transcripts, brain cell dysfunction in our model. In this developmental program we propose to 1) test the efficacy of antiretroviral drugs for prophylaxis of acute peripheral and central nervous system infection of adult and young mice by EcoHIV/NDK and 2) test the efficacy of antiretroviral drugs for reduction of established EcoHIV/NDK infection in peripheral tissues and brain and consequential neuropathogenesis in young mice. Virus burden in lymphocytes, macrophages, and the brain and activation of brain cell gene expression will be determined by real-time PCR and microglial activation will be assessed by immunocytochemistry. This program directly investigates whether drugs with poor access to the brain can prevent establishment of a nervous system reservoir of HIV-1 and brain disease, whether virus resident in the brain is sensitive to HAART agents, and to what extent inhibition of ongoing virus replication depletes viral reservoirs in brain cells, macrophages, and bone marrow and ameliorates brain disease. This developmental program is proposed to guide future translational studies in this animal model to screen or develop new agents for their ability to prevent HIV-1-associated neuropathogenesis. PUBLIC HEALTH RELEVANCE HIV-1 infection causes immunodeficiency and often nervous system disorders resulting in memory lapses, confusion, and poorly controlled movements. This application proposes to use mice experimentally infected by HIV-1 and antiviral drugs now used in human beings to determine whether they block infection and disease in the mouse brain. In addition, the application will test if drugs given to mice after infection actually eliminate virus from the brain, giving promise for the ability of antiviral drugs to control the nervous system disease seen in infected human beings.