Host Glycomic Modulation of HIV-associated Neuro-inflammation During Viral Suppression

项目概述：尽管抗逆转录病毒疗法(ART)得到了广泛应用，但神经性心脏病的流行 炎症仍然很高，据信涉及&gt；40%的HIV+患者。这种炎症状态很可能 导致认知功能障碍，影响日常功能，并增加发病率和死亡率 抑制抗逆转录病毒药物的艾滋病毒感染者。然而，这种神经背后的生理过程- 人们对炎症仍知之甚少。这项建议是建立在我们正在进行的关于血糖是否 循环糖蛋白和外切体的改变在HIV相关神经细胞的发病机制中发挥了作用。 炎症和认知障碍。我们的初步数据显示，更高水平的PRO- 血浆、血浆外切体和脑脊液(CSF)中的炎性低唾液酸聚糖 与HIV+抗逆转录病毒药物抑制者更严重的神经损害有关。然而，无论是血糖 在HIV感染过程中，改变驱动神经炎症的机制尚不清楚。在本项目中，我们将测试中央 假设宿主的血糖调节失调，特别是循环糖蛋白的低唾液酸化 和外切体，有助于神经炎症和艾滋病毒相关的共同- 影响中枢神经系统(CNS)的疾病。 在目标1中，我们将确定低唾液酸聚糖神经炎性作用的机制。 在抗逆转录病毒药物抑制的艾滋病毒感染期间。我们将使用超唾液酸化和低唾液酸化的糖蛋白和 在体外模型中从患有神经损伤的HIV+ART+患者的血浆中分离出外切体 单核细胞的活化/炎症和迁移，在存在或不存在多糖信号抑制物的情况下。在……里面 目的2，我们将检验这一假说，即操纵循环唾液酸水平会影响神经细胞- HIV相关神经损伤小鼠模型中的炎症和认知行为。我们将使用 EcoHIV小鼠模型(使用能够感染小鼠的嵌合HIV)最近被成功地用于 HIV致病机制和神经损伤的模型。使用急性和慢性EcoHIV感染的小鼠 (有或没有ART)，接受唾液酸纳米粒和唾液酸酶抑制剂的组合或 作为对照，我们将评估：(1)认知损害程度；(2)脑标记物 炎症/免疫激活[基因芯片和免疫组织化学]；(3)脑组织中EcoHIV的表达 [qPCR]；以及(4)脑组织和脑源性外切体的唾液酸化[凝集素阵列和流式细胞术]。 我们将利用新兴的糖组学领域的最新进展和一个动物模型 HIV相关的神经损伤，以澄清神经炎症之间的相互关联机制， 认知功能障碍和宿主免疫力。我们的工作旨在为发现新的多糖创造一个新的范例- 基于相互作用，可以有针对性地预防艾滋病毒携带者持续存在的神经炎症 尽管病毒受到抑制。

PROJECT SUMMARY: Despite the widespread use of antiretroviral therapy (ART), the prevalence of neuro- inflammation remains high and is believed to involve >40% of HIV+ individuals. This inflammatory state likely causes cognitive dysfunction that impacts everyday functioning and increases morbidity and mortality among ART-suppressed HIV-infected individuals. However, the physiological processes underlying this neuro- inflammation remain poorly understood. This proposal builds on our ongoing investigation on whether glycomic alterations in circulating glycoproteins and exosomes play a role in the pathogenesis of HIV-associated neuro- inflammation and cognitive disorders. Our preliminary data demonstrate that higher levels of the pro- inflammatory hypo-sialylated glycans in plasma, plasma exosomes, and cerebrospinal fluid (CSF) strongly correlate with worse neurological impairment in HIV+ ART-suppressed individuals. However, whether glycomic alterations drive neuro-inflammation during HIV infection remains unknown. In this project we will test the central hypothesis that host glycomic dysregulation, in particular hypo-sialyation of circulating glycoproteins and exosomes, contributes to neuroinflammation and the pathogenesis of HIV-associated co- morbidities affecting the central nervous system (CNS). In Aim 1, we will identify the mechanism of the neuro-inflammatory effects of hypo-sialylated glycans during ART-suppressed HIV infection. We will use hyper-sialylated and hypo-sialylated glycoproteins and exosomes isolated from the plasma of HIV+ ART+ individuals with neurological impairments, in an ex-vivo model of monocyte activation/inflammation and migration, in the presence or absence of glycan signaling inhibitors. In Aim 2, we will test the hypothesis that manipulating the levels of circulating sialic acid impacts neuro- inflammation and cognitive behavior in a mouse model of HIV-associated neurological impairment. We will use the EcoHIV mouse model (using chimeric HIV capable of infecting mice) that was recently used as a successful model of HIV pathogenesis and neurological impairment. Using acutely and chronically EcoHIV-infected mice (with and without ART), that receive either a combination of sialic acid nanoparticles and sialidase inhibitors or nude nanoparticles as controls, we will evaluate: (1) levels of cognitive impairment; (2) brain markers of inflammation/immune activation [gene array and immunohistochemistry]; (3) EcoHIV expression in brain tissues [qPCR]; and (4) sialylation of brain tissues and brain-derived exosomes [lectin array and flow cytometry]. We will take advantage of recent advances in the emerging field of glycomics and an animal model of HIV-associated neurological impairment, to clarify the inter-related mechanisms between neuro-inflammation, cognitive dysfunction, and host immunity. Our work aims to create a new paradigm for discovering novel glycan- based interactions that can be targeted to prevent neuro-inflammation that persists in individuals living with HIV despite viral suppression.