Role of oral herpesvirus microbiota in pathogenesis of HIV mother to child transmission

项目摘要/摘要 每年约有25万婴儿感染人类免疫缺陷病毒(HIV-1)，尽管 抗逆转录病毒预防，表明有必要采取替代预防战略。母婴 母婴传播是艾滋病毒从母亲传播到胎儿和婴儿的重要途径；然而， 人类免疫缺陷病毒母婴传播的分子机制尚不清楚。我们最近的研究表明，90%的病毒粒子 内化到婴儿扁桃体上皮中的是隔离在内体中的，包括多囊泡体。 (MVB)和上皮细胞空泡，最多9天。相比之下，这种长期的细胞内隔离 在成人扁桃体上皮细胞中未观察到HIV的感染：细胞内病毒迅速灭活。这是 与我们发表的工作一致，表明在成人极化上皮细胞中细胞内HIV被灭活 通过高水平表达抗HIV先天免疫蛋白人β防御素2(HBD2)和HBD3。 然而，胎儿和婴儿口腔上皮细胞不表达HBDS，导致了传染性艾滋病毒的传播。 在正在进行的实验中，我们发现单纯疱疹病毒-1(HSV-1)与人类 婴儿扁桃体顶端(粘膜)表面的巨细胞病毒(HCMV)和EB病毒(EBV) 含有HIV-1的上皮细胞导致HIV病毒粒子的胞吐，而HIV病毒粒子对外周血具有感染性 单个核细胞(PBMC)。HSV、HCMV和EBV是婴儿的口腔微生物区系，它们与 含HIV的婴儿扁桃体上皮细胞可能导致HIV释放和传播到CD4+T细胞 淋巴细胞、巨噬细胞和朗格罕/树突状细胞(LCS/DC)，导致HIV MTCT。几乎什么都没有 已知疱疹病毒口腔微生物区系在艾滋病毒母婴传播中的作用。因此，对分子的研究 HSV、HCMV和EBV相关HIV从新生儿/婴儿口腔上皮传播到 艾滋病毒敏感细胞无疑将有助于更好地了解与口腔微生物区系相关的 HIV母婴传播的发病机制及围产期预防治疗新策略的研究进展 病毒感染。因此，这项建议的具体目的是(1)研究其分子机制。 HSV、HCMV和EBV诱导的婴儿扁桃体上皮中含有隔离的HIV的HIV胞吐；(2) 研究HSV、HCMV和EBV在HIV MTCT中通过破坏粘膜上皮和 HIV敏感细胞的激活；以及(3)研究囊泡内HIV灭活的可能机制 通过抗病毒天然免疫蛋白人β防御素2(HBD2)和HBD3。这项工作将大大推进 了解疱疹病毒口腔微生物区系在HIV MTCT发病机制中的作用。建议进行的研究 可能导致在抑制或减少疱疹病毒的基础上建立新的治疗方法- 相关的HIV从粘膜上皮细胞扩散到HIV靶细胞并清除上皮内 这反过来又可以减少艾滋病毒母婴传播。

Project Summary/Abstract Approximately 250,000 infants acquire human immunodeficiency virus (HIV-1) infection annually despite antiretroviral prophylaxis, suggesting the need for alternative prevention strategies. Mother-to-child transmission (MTCT) is an important pathway for the spread of HIV from mother to fetus and infant; however, the molecular mechanisms of HIV MTCT are poorly understood. Our recent work showed that >90% of virions internalized into infant tonsil epithelium are sequestered in the endosomes, including multivesicular bodies (MVBs) and vacuoles of epithelial cells, for up to 9 days. In contrast, such prolonged intracellular sequestration of HIV was not observed in adult tonsil epithelial cells: intracellular virus was rapidly inactivated. This is consistent with our published work showing that intracellular HIV is inactivated in adult polarized epithelial cells by high-level expression of anti-HIV innate immune proteins human beta defensin 2 (HBD2) and HBD3. However, fetal and infant oral epithelial cells did not express HBDs, leading to transmission of infectious HIV. In ongoing experiments we have found that the interaction of herpes simplex virus-1 (HSV-1), human cytomegalovirus (HCMV), and Epstein-Barr virus (EBV) with the apical (mucosal) surface of infant tonsil epithelial cells containing HIV-1 leads to the exocytosis of HIV virions, which are infectious for peripheral blood mononuclear cells (PBMCs). HSV, HCMV, and EBV are oral microbiota of infants, and their interaction with infant tonsil epithelial cells containing HIV may lead to the release and spread of HIV into CD4+ T lymphocytes, macrophages, and Langerhans/dendritic cells (LCs/DCs), leading to HIV MTCT. Virtually nothing is known about the role of herpesvirus oral microbiota in HIV MTCT. Therefore, investigation of the molecular mechanisms underlying HSV-, HCMV-, and EBV-associated HIV spread from neonatal/infant oral epithelia into HIV-susceptible cells will undoubtedly lead to a better understanding of the oral microbiota-associated pathogenesis of HIV MTCT and the development of a new preventive therapeutic strategy against perinatal viral infection. Accordingly, the specific aims of this proposal are (1) To study the molecular mechanisms of HSV-, HCMV-, and EBV-induced HIV exocytosis in infant tonsil epithelium containing sequestered HIV; (2) To investigate the role of HSV, HCMV, and EBV in HIV MTCT through disruption of mucosal epithelium and activation of HIV-susceptible cells; and (3) To study the potential mechanisms of intravesicular HIV inactivation by antiviral innate immune proteins human beta defensin 2 (HBD2) and HBD3. This work will greatly advance knowledge of the role of herpesvirus oral microbiota in the pathogenesis of HIV MTCT. The proposed studies may lead to the establishment of new therapeutic approaches based on inhibition or reduction of herpesvirus- associated HIV spread from mucosal epithelial cells into HIV target cells and elimination of intraepithelial reservoirs, which in turn may reduce HIV MTCT.