Role of Exosomes in the Crosstalk Between Brain Endothelium and HIV Neuroinvasion

摘要 外切体正在出现，在免疫监测和神经元存活方面发挥重要作用 中枢神经系统(CNS)，因为它们介导神经元和 其他脑细胞，包括星形胶质细胞和神经血管内皮细胞。然而，它的作用是 外切体在HIV介导的神经侵袭中的作用在很大程度上是未知的。我们最近发现外切体 从HIV感染者的血浆中分离出的微小RNA-17(miR-17)水平显著升高 17)和miR-20a，可以靶向紧密连接蛋白ZO-1和JAM-2。使用CELL进行进一步的先导研究 培养衍生的外切体显示，来自HIV感染的巨噬细胞的外切体可以破坏血脑 屏障(BBB)完整性。因此，我们假设exosome来源于HIV感染者的血浆。 受试者含有破坏血脑屏障功能的miRNAs，促进了有机致病病毒的传播 并导致神经退行性变。我们提出了两个具体目标来解决这个问题 假设：目的1.研究HIV感染者血浆外切体的作用 未感染对血脑屏障功能的控制并确定miR-17和miR-20a在这一过程中的作用。目标2. 目的：比较HIV感染者血浆和脑脊液外切体的miRNA谱。 患有或不伴有神经认知障碍的感染者。外切体的功能意义和 差异表达的外体miRNAs将在神经元存活、星形胶质细胞 分化和血脑屏障功能。这个项目，通过体外和体内研究，应该提供新的 对中枢神经系统艾滋病毒感染的病因学洞察。

Summary Exosomes are emerging to play an important role in immune surveillance and neuronal survival of the central nervous system (CNS), as they mediate the intercellular communications between neurons and other brain cells, including astrocytes and neurovascular endothelial cells. However, the role of exosomes in HIV-mediated neuroinvasion is largely unknown. We recently identified that exosomes isolated from the plasma of HIV-infected subjects contain significantly high levels of microRNA-17 (miR- 17) and miR-20a that can target tight junction proteins ZO-1 and JAM-2. A further pilot study using cell culture-derived exosomes showed that exosomes from HIV-infected macrophages breached blood-brain barrier (BBB) integrity. Thus, we hypothesize that exosomes derived from plasma of HIV-infected subjects contain miRNAs that impair BBB functions, facilitating organotropic viral dissemination to the brain and resulting in neurodegeneration. We propose two specific aims to address this hypothesis: Aim 1. To investigate the effect of plasma exosomes from HIV-infected subjects or uninfected controls on BBB functions and identify the role of miR-17 and miR-20a in this process. Aim 2. To profile and compare the miRNA spectra of exosomes from the plasma and cerebrospinal fluid of HIV- infected subjects with or without neurocognitive disorders. The functional significance of the exosomes and the differentially expressed exosomal miRNAs will be validated on neuronal survival, astroglial differentiation and BBB functions. This project, with both in vitro and in vivo studies, should provide novel pathogenetic insights into HIV infection of the CNS.