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

项目总结/摘要 每年约有250 000名婴儿感染人类免疫缺陷病毒（HIV-1）， 抗逆转录病毒预防，表明需要替代预防策略。母婴传播 母婴传播（MTCT）是HIV从母亲传播到胎儿和婴儿的重要途径;然而， 艾滋病毒母婴传播的分子机制知之甚少。我们最近的研究表明，超过90%的病毒粒子 内化到婴儿扁桃体上皮中的内体被隔离在内体中，包括多泡体 （MVB）和上皮细胞的空泡，长达9天。相反，这种长时间的细胞内隔离 在成人扁桃体上皮细胞中未观察到HIV感染：细胞内病毒被迅速灭活。这是 与我们发表的工作一致，表明细胞内HIV在成人极化上皮细胞中失活 通过高水平表达抗HIV先天免疫蛋白人β防御素2（HBD 2）和HBD 3。 然而，胎儿和婴儿口腔上皮细胞不表达HBDs，导致传染性HIV的传播。 在正在进行的实验中，我们已经发现单纯疱疹病毒-1（HSV-1）、人 巨细胞病毒（HCMV）和EB病毒（EBV）与婴儿扁桃体的顶端（粘膜）表面 含有HIV-1的上皮细胞导致HIV病毒体的胞吐作用，其对外周血具有感染性 单核细胞（PBMC）。HSV、HCMV和EBV是婴儿的口腔微生物群，并且它们与 含有HIV的婴儿扁桃体上皮细胞可能导致HIV释放并扩散到CD 4 + T细胞中， 淋巴细胞、巨噬细胞和朗格汉斯/树突状细胞（LC/DC），导致HIV MTCT。几乎没有 已知疱疹病毒口腔微生物群在HIV母婴传播中的作用。因此，研究分子 HSV-、HCMV-和EBV相关的HIV从新生儿/婴儿口腔上皮细胞扩散到 HIV易感细胞的研究无疑将有助于我们更好地了解与口腔微生物相关的 艾滋病母婴传播的发病机制及围产期艾滋病防治新策略的研究 病毒感染因此，本建议的具体目标是：（1）研究 HSV-、HCMV-和EBV诱导的含有隔离HIV的婴儿扁桃体上皮中的HIV胞吐;（2） 通过破坏粘膜上皮，研究HSV、HCMV和EBV在HIV MTCT中的作用， 研究囊泡内HIV灭活的可能机制 抗病毒先天免疫蛋白人β防御素2（HBD 2）和HBD 3。这项工作将大大推进 了解疱疹病毒口腔微生物群在艾滋病毒母婴传播发病机制中的作用。拟议的研究 可能导致建立基于抑制或减少疱疹病毒的新治疗方法- 相关的HIV从粘膜上皮细胞扩散到HIV靶细胞， 这反过来又可能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.