Markers of HIV Brain Disease under HAART: Validation in a Mouse Model

描述(由申请人提供)：这项竞争性修订申请通过增加一个新的目标Aim 5来扩大父母资助的范围，该目标致力于对感染HIV-1的小鼠进行行为/认知评估。我们的研究是基于这样一个假设，即长期存活的HIV-1感染细胞在现有治疗中持续存在，导致大脑生理的核心变化。这些细胞持续产生病毒蛋白可导致累积性炎症、抗病毒和氧化应激反应，从而影响神经功能。我们在母方拨款中检验这一假说的四个具体目标是：1)建立代表轻度艾滋病毒CNS疾病患者的全基因组脑基因表达谱；2)确定在存在抗逆转录病毒治疗的情况下，人类大脑中持续轻度艾滋病毒CNS疾病的生物路径和生物标记物；3)在嵌合、神经侵袭性HIV-1、EcoHIV感染的小鼠的大脑中验证选定的HIV CNS疾病标志物，这会导致小鼠出现类似MND的轻微神经病理变化；4)使用MND的小鼠模型，测试轻度、慢性HIV CNS疾病依赖于不受现有抗逆转录病毒治疗影响的低水平病毒转录的假设。我们在目标1-3方面取得了重大进展。我们发现，感染EcoHIV的小鼠会出现轻微的认知障碍，这种障碍在感染后至少会持续两个月，并且不会涉及广泛的神经病理或病毒性脑炎，类似于人类患者的MND。由于在小鼠中很容易测量出症状性认知障碍，小鼠感染EcoHIV现在为人类提供了更真实的HIV-1中枢神经系统疾病的代表。对小鼠的行为测试不是父母拨款的一部分(见上文的目标)。在这里，我们建议使用竞争性修订应用程序的机制来在父应用程序中建立行为组件。由于资金期限有限，我们的申请主要建议建立和优化行为测试方法，包括投资所需的设备和额外的人员。然后将在补充期间使用行为测试来评估我们已经确定的MND标记。提出了以下目标，并将其归入一个新的具体目标5：A)购买设备并测试和选择最佳的行为测试，以测量EcoHIV感染引起的小鼠的学习和短期和长期记忆障碍；B)确定行为障碍相对于外周EcoHIV感染过程和宿主免疫状态的时间进程；C)开始检测伴随着小鼠神经认知障碍发展的HIV-1神经发病机制的脑病理和细胞标志物的表达。我们相信，通过允许对HIV-1神经认知疾病进行实验评估，从识别病毒诱导的大脑基因组范围的变化到验证它们在临床相关行为测试中的重要性，拟议的行为组件将极大地丰富父程序。 公共卫生相关性：这项申请是为了补充正在进行的关于人类和小鼠基因产物的研究，这些基因产物与HIV-1感染期间的脑部疾病有关。我们发现，感染HIV-1的小鼠也会出现学习和记忆问题，本研究将结合正在进行的这些动物脑细胞基因表达变化的研究，系统地评估这些行为问题。

DESCRIPTION (provided by applicant): This Competitive Revision Application requests funds to expand the scope of the parent grant by adding a new objective, Aim 5, dedicated to behavioral/cognitive evaluations of HIV-1 infected mice. Our research is based on the hypothesis that there are core changes in brain physiology arising from long- lived HIV-1 infected cells that persist through existing therapies. Unabated production of viral proteins by these cells can cause cumulative inflammatory, antiviral, and oxidative stress reactions that affect neuronal function. We test this hypothesis in the parent grant in four Specific Aims to: 1) establish genome-wide brain gene expression profiles representative of patients with milder forms of HIV CNS disease; 2) identify biological pathways and biomarkers in the human brain characteristic of continuing mild HIV CNS disease in the presence of antiretroviral treatment; 3) validate selected markers of mild HIV CNS disease in brains of mice infected with chimeric, neuroinvasive HIV-1, EcoHIV, which causes mild neuropathological changes in mice similar to MND; 4) using this mouse model of MND, test the hypothesis that mild, chronic HIV CNS disease depends upon low level virus transcription unaffected by existing antiretroviral treatment. We have made significant progress in Aims 1-3. We found that EcoHIV infected mice develop mild cognitive impairments that last at least two months after infection and do not involve extensive neuropathology or viral encephalitis, similar to MND in human patients. With symptomatic cognitive impairment easily measured in mice, EcoHIV infection of mice now provides a more faithful representation of HIV-1 CNS disease in people. Behavioral testing in mice was not part of the parent grant (See Aims above). Here we propose to use the mechanism of the Competitive Revision Application to establish a behavioral component in the parent application. Because of its limited funding period, our application proposes primarily to establish and optimize behavioral testing methods, including investment in the required equipment and additional personnel. The behavioral testing will then be employed for the duration of the supplement for evaluation of MND markers that we have already identified. The following objectives are proposed, grouped under a new Specific Aim 5: A) To purchase equipment and test and select optimal behavioral tests measuring learning and short- and long-term memory for scoring behavioral/cognitive deficits induced by EcoHIV infection in mice; B) To determine the time course of the behavioral impairment relative to the course of peripheral EcoHIV infection and host immune status; C) To begin to examine brain pathology and expression of cellular markers of HIV-1 neuropathogenesis accompanying development of neurocognitive impairments in mice. We believe that the proposed behavioral component will significantly enrich the parent program by allowing experimental evaluation of HIV-1 neurocognitive disease, from identifying virus-induced genome- wide changes in the brain to verifying their importance in clinically relevant behavioral tests. PUBLIC HEALTH RELEVANCE: This application is proposed to supplement ongoing studies on the human and mouse gene products that associate with brain disease during HIV-1 infection. We have found that HIV-1 infected mice also develop problems in learning and memory and this study will systemically evaluate these behavioral problems in correlation to the ongoing studies on changes in brain cell gene expression in these animals.