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

描述（由申请人提供）：本竞争性修订申请申请资金，通过增加一个新的目标，目标5，专门用于HIV-1感染小鼠的行为/认知评估，以扩大母基金的范围。我们的研究是基于这样的假设，即通过现有的治疗方法，长期存在的HIV-1感染细胞会引起脑生理学的核心变化。这些细胞不断产生的病毒蛋白会引起累积的炎症、抗病毒和氧化应激反应，从而影响神经元的功能。我们在四个特定目标中验证了这一假设：1)建立代表轻度HIV CNS疾病患者的全基因组脑基因表达谱；2)在接受抗逆转录病毒治疗的情况下，确定持续轻度HIV中枢神经系统疾病的人脑特征的生物学途径和生物标志物；3)验证嵌合性、神经侵袭性HIV-1、EcoHIV感染小鼠大脑中轻度HIV CNS疾病的选定标记物，这些标记物可引起与MND相似的小鼠轻度神经病理改变；4)利用这种小鼠MND模型，验证轻度、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的小鼠在感染后至少持续两个月的轻度认知障碍，不涉及广泛的神经病理学或病毒性脑炎，类似于人类患者的MND。由于在小鼠中很容易测量到症状性认知障碍，小鼠的EcoHIV感染现在提供了人类HIV-1中枢神经系统疾病的更忠实的代表。在老鼠身上进行的行为测试不属于父母资助的一部分（见上文的目的）。在这里，我们建议使用竞争性修订应用程序的机制在父应用程序中建立一个行为组件。由于资助期限有限，我们的申请主要建议建立和优化行为测试方法，包括对所需设备和额外人员的投资。行为测试将在补充期内用于评估我们已经确定的MND标记。在新的特定目标5下，提出了以下目标：a)购买设备和测试并选择最佳的行为测试，测量学习和短期和长期记忆，以评分小鼠由EcoHIV感染引起的行为/认知缺陷；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过程；C)开始在小鼠中检测伴随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全基因组变化到验证其在临床相关行为测试中的重要性，所提出的行为成分将显著丰富母体程序。

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.