Elucidating the mechanism of progesterone-induced permissivity in the upper female reproductive tract

项目总结/摘要： 在世界范围内，妇女在艾滋病毒流行中首当其冲，预防艾滋病毒传播的有效手段是 女性仍然是一个难以捉摸的目标。实现这一目标受到我们对早期 性传播过程中女性生殖道（FRT）发生的事件。特别是，如何居民艾滋病毒- 易感细胞和非易感细胞影响病毒复制，并感知和应答HIV感染，但不 很好理解。虽然上FRT窝藏艾滋病毒易感细胞，暴露于精液成分， 并且在SIV传播模型中被早期感染，它作为HIV进入的门户未被充分研究。在自行车运动中 女性，上FRT的子宫内膜广泛重塑，以响应性类固醇雌激素 和孕酮。孕酮和孕激素，孕酮的合成模拟物，与 在人类和非人类灵长类动物模型中增加对HIV感染的易感性。因此，我们认为， 了解这些化合物如何影响子宫内膜可能会深入了解艾滋病毒如何传播 通过这个组织感染。在我们的初步研究中，孕激素降低了子宫内膜屏障功能， 上皮细胞，其可以促进HIV从管腔进入上皮细胞的间质区室。 子宫内膜间质内居住着密集的子宫内膜间质成纤维细胞。虽然这些 细胞不允许HIV感染，在与CD 4 + T细胞共培养时，它们使感染增加高达81- 100%。 折相反，当孕酮缺乏时，上皮屏障的完整性得以维持， 子宫内膜上皮细胞通过诱导共培养的CD 4 + T细胞的抗病毒状态来限制感染。使用 一个从子宫内膜活检细胞重建的离体系统，我们将研究其分子生物学特性。 导致胆固醇诱导的渗漏的机制（具体目标1），增加对 基质成纤维细胞介导的感染（特异性目的2）和上皮诱导的病毒限制（特异性目的 3)在上FRT。因为孕酮诱导的上皮渗透性也可能发生在较低的FRT中， 我们还将使用从子宫颈外活检分离的细胞来测试该模型。拟议的研究将 加深我们对FRT中HIV传播和限制的理解，并提供一个强大的体外模型 系统检查性类固醇和组织驻留细胞在艾滋病毒的背景下复杂的相互作用 易感性这个系统和我们已经建立的表型分析工具也可以适用于研究艾滋病毒 在其他粘膜入口如肠粘膜和男性包皮中的传播和限制。

PROJECT SUMMARY / ABSTRACT: Worldwide, women bear the brunt of the HIV epidemic, and an effective means to prevent HIV transmission to women remains an elusive goal. Achieving this goal is hampered by our incomplete understanding of the early events in the female reproductive tract (FRT) during sexual transmission. In particular, how resident HIV- susceptible and non-susceptible cells affect viral replication, and sense and respond to HIV infection, are not well understood. Although the upper FRT harbors HIV-susceptible cells, is exposed to semen components, and is infected early in SIV transmission models, it is understudied as a portal of entry for HIV. In cycling women, the endometrium of the upper FRT is extensively remodeled in response to the sex steroids estrogen and progesterone. Progesterone and progestins, synthetic mimics of progesterone, are associated with increased susceptibility to HIV infection in humans and in non-human primate models. Therefore, understanding how these compounds affect the endometrium may yield insights into how HIV establishes infection through this tissue. In our preliminary studies, progesterone decreased barrier function of endometrial epithelial cells, which can facilitate entry of HIV from the luminal cavity into the stromal compartment of the endometrium. Within the stroma resides a dense population of endometrial stromal fibroblasts. Although these cells were not permissive to HIV infection, in co-culture with CD4+ T cells they increased infection by up to 81- fold. In contrast, when progesterone was absent, epithelial barrier integrity was maintained, and the intact layer of endometrial epithelial cells restricted infection by eliciting an antiviral state in co-cultured CD4+ T cells. Using an ex vivo system reconstituted from cells from endometrial biopsies, we will examine the molecular mechanisms responsible for progesterone-induced leakiness (Specific Aim 1), the increased susceptibility to infection mediated by stromal fibroblasts (Specific Aim 2), and epithelia-induced viral restriction (Specific Aim 3) in the upper FRT. Because progesterone-induced epithelial permeability may also occur in the lower FRT, we will additionally test this model using cells isolated from ectocervical biopsies. The proposed studies will deepen our understanding of HIV transmission and restriction in the FRT and provide a robust ex vivo model system to examine the complex interplay between sex steroids and tissue-resident cells in the context of HIV susceptibility. This system and the phenotyping tools we have established can also be adapted to study HIV transmission and restriction in other mucosal portals of entry such the intestinal mucosa and the male foreskin.