Toward Understanding the Role of Adult Human Microglia in the Ongoing Persistence of HIV and its Associated Neuropsychiatric Comorbidities

项目摘要 尽管有效地抑制了HIV复制，但目前的治疗不能提供绝育免疫， 根除解剖学上的储库在HIV动物模型和感染者中进行的研究表明， 大脑中长寿命的小胶质细胞（MG）在储存中发挥重要作用的可能性很大。 形成/维持。升高的炎性细胞因子和感染HIV DNA的免疫细胞已经被证实是HIV感染的主要原因。 在接受抗逆转录病毒治疗（ART）的HIV感染者的CSF中发现， 健康和体内平衡。然而，深入了解在人类MG中起作用的分子机制- HIV宿主-病原体相互作用促进储库的形成和维持是非常困难的， 最近，几乎难以研究。要取得进展，必须克服三个关键限制。首先，是 获得大量成人MG用于实验的能力有限。第二，培养的人MG 必须在体外相对较长的寿命，以便进行抗逆转录病毒治疗中断和再激活 问题研究第三，为了推进翻译目标，测试人成人MG的完全补体的体内模型 功能，并验证在体外获得的机制研究结果。几个小组取得了令人振奋的进展 在这些方面取得了进展。马修斯等人，报告了成功植入和艾滋病毒感染的 将来自胎儿脐带血祖细胞的人MG植入NOG-IL-34转基因小鼠的脑中。最近的一 Rai等人研究，比较转录组发现，在先前验证的MG保守序列中，约78%的保守性 人血液单核细胞衍生的MG、iPSC衍生的人MG和成人人组织之间的基因特征 MG与两个MG细胞系不共享，表明可能的前进路径。总的来说，这些数据显示 在小鼠和人类中发现血液髓系祖细胞亚群保留了遗传可塑性和弹性 这是一个对大脑正常运作至关重要的生物系统。本次探索性的 建议是建立在从血液髓系祖细胞培养成人MG的进展上，以允许研究 的体细胞遗传学和提高体外和体内实验模型中的neuroHIV的翻译潜力。 长期的目标是破译小胶质细胞和炎症刺激对维持神经细胞增殖的贡献。 HIV中枢神经系统储存库具体目标是：1）表征人类血液的程度、广度和保真度 - 来自无关的成年健康供体的髓系祖细胞，以在脑中填充并充当HIV储库， 2)鉴定和研究HIV感染成人中促炎基因网络表达动力学的层次 人类小胶质细胞和对艾滋病毒的影响持久性在艺术。从拟议的研究结果将奠定 为深入研究MG功能、促炎信号传导和潜在的发展奠定了基础。 新的战略，以确定和理解机制和对心理健康的影响，艾滋病毒- 感染了大脑中的骨髓储库

PROJECT SUMMARY Despite effective suppression of HIV replication, current treatments do not provide sterilizing immunity or eradicate anatomical reservoirs. Studies conducted in HIV animal models and infected humans demonstrate the strong likelihood that the brain's long-lived microglia (MG) play an essential role in reservoir formation/maintenance. Elevated inflammatory cytokines and infected immune cells with HIV DNA have been found in the CSF of HIV-infected people on antiretroviral therapy (ART), revealing the increased risks to brain health and homeostasis. However, a deep understanding of the molecular mechanisms at work in human MG- HIV host-pathogen interaction that foments reservoir formation and maintenance has been very difficult and until recently, near intractable to study. Three key limitations must be overcome to achieve progress. First, is the limited ability to procure large quantities of adult human MG for experimentation. Second, cultured human MG must be relatively long-lived in vitro in order to conduct antiretroviral treatment interruption and reactivation studies. Third, to advance translational goals, an in vivo model to test the full complement of human adult MG function is needed and to validate mechanistic findings obtained in vitro. Exciting progress by several groups has been made on these fronts. Mathews et al., reported on the successful engraftment and HIV infection of human MG derived from fetal cord blood progenitors into the brains of NOG-IL-34 transgenic mice. A recent study by Rai et al., comparing transcriptomes found ~78% conservation in a previously validated MG conserved gene signature between human blood monocyte-derived MG, iPSC-derived human MG and human tissue adult MG that was not shared with two MG cell lines suggesting a possible path forward. Collectively, these data show that a subset of blood myeloid progenitors found in both mouse and man, retain genetic plasticity and resiliency built into a biological system that is overall crucial for proper brain functioning. The goals of this exploratory proposal are to build upon advances in culturing adult human MG from blood myeloid progenitors to allow study of somatic genetics and improve the translational potential of neuroHIV in vitro and in vivo experimental models. The long-term goal is to decipher the contribution of microglia and inflammatory stimuli to the maintenance of the HIV CNS reservoir. The Specific Aims are to: 1) characterize the extent, breadth and fidelity of human blood myeloid progenitors from unrelated adult healthy donors to populate and serve as HIV reservoirs in the brain and 2) identify and study the hierarchy of proinflammatory gene network expression kinetics in HIV-infected adult human microglia and impact on HIV persistence during ART. The findings from the proposed studies will lay the groundwork for deeper investigation of MG function, proinflammatory signaling, and the potential development of novel strategies for identifying and understanding the mechanisms and impact on mental health of HIV- infected myeloid reservoirs in the brain.