Host-Microbiota Interactions and Chlamydia Trachomatis Infection Outcomes

项目摘要 人类性传播感染（STI）的风险取决于多种生物因素，其中 “允许”性传播感染的宫颈阴道微生物群的出现是突出的。所述微生物组合物 与细菌性阴道病综合征相关的观察结果相似， 通常由高pH（>4.5）、不存在乳杆菌属（Lactobacillus spp.）和一个严格的 和兼性厌氧菌，例如阴道加德纳菌（Gardnerella vagulae）、阴道奇异菌（Atopobium vaginae）、巨球菌属（Megaspaera spp.），以及Prevotella spp.相比之下，典型的“非许可”微生物群由几种乳杆菌中的一种占主导地位， 人类宫颈阴道微生物群的独特特征。非许可性的机制 子宫颈阴道微生物群对性传播感染的保护作用仍然知之甚少，因为没有动物或细胞 迄今为止开发的培养模型系统以其天然的形式令人满意地再现了宫颈阴道粘膜， 环境作为实验感染的目标。因此，我们对发病机制的认识， 性传播感染是不完整的，特别是因为它涉及到人类宫颈阴道微生物群的关键作用。我们有 建立了广泛的初步数据，支持该项目的科学前提，并指出，非- 允许的固有微生物群与宫颈阴道上皮相互作用以建立稳态 阻断性传播感染和/或降低疾病严重程度。相反，允许的微生物群破坏宿主细胞 体内平衡，从而允许STI进展。宫颈阴道粘膜的高级3D器官型模型 消除现有模型固有的伦理和生物学限制的方法将用于测试这一假设， 用的是全世界最流行的性病病原体沙眼衣原体我们的目标是开发一个更好的 了解宿主-微生物群的相互作用以及它们如何调节C.沙眼感染在 在这个项目中，将利用不同类型的重建微生物群的3D器官型模型 询问关于不同类型的微生物群（允许和非允许）如何调节的具体问题 上皮细胞功能（目标1）与其对衣原体感染的易感性/抗性（目标2）的关系。 我们还将评估该模型用于测试预防性（目标2）和治疗性（目标3）的临床前潜力 针对性传播感染的干预措施。对于这些研究，我们将充分利用最先进的显微镜和 RNA测序方法用于鉴定和表征结构和宿主的微生物群特异性改变 上皮内稳态和扩大我们的理解之间的三角关系的主机， microbiota和C.沙眼

PROJECT SUMMARY The risk of sexually transmitted infection (STI) in humans depends on multiple biological factors, among which the occurrence of a cervicovaginal microbiota that is `permissive' to STI stands out. The microbial composition of a STI-permissive microbiota is similar to that observed in association with the syndrome of bacterial vaginosis, a condition that is generally defined by a high pH (>4.5), the absence of Lactobacillus spp. and an array of strict and facultative anaerobes such as Gardnerella vaginalis, Atopobium vaginae, Megasphaera spp., and Prevotella spp. In contrast, a typical `non-permissive' microbiota is dominated by one of several species of Lactobacillus, a unique feature of the human cervicovaginal microbiota. The mechanism(s) by which a non-permissive cervicovaginal microbiota provides protection against STIs remains poorly understood, as no animal or cell culture model system developed to date satisfactorily reproduces the cervicovaginal mucosa in its natural environment as a target for experimental infection. As a consequence, our knowledge of the pathogenesis of STIs is incomplete, particularly as it pertains to the critical role of the human cervicovaginal microbiota. We have established extensive preliminary data that support the scientific premise of this project and states that a non- permissive indigenous microbiota interacts with the cervicovaginal epithelium to establish a homeostatic state that blocks STI and/or reduces disease severity. Conversely, a permissive microbiota disrupts host cell homeostasis, thereby allowing STI to progress. Advanced 3D organotypic models of the cervicovaginal mucosa that eliminate the inherent ethical and biological limitations of existing models will be used to test this hypothesis, using the most prevalent agent of STIs worldwide, Chlamydia trachomatis. We aim to develop a better understanding of the host-microbiota interactions and how they modulate the fate of C. trachomatis infection. In this project, 3D organotypic models colonized with different types of reconstructed microbiota will be exploited to ask specific questions about how different types of microbiota (permissive and non-permissive) modulate epithelial cell functioning (Aim 1) in relationship to their susceptibility/resistance to chlamydial infection (Aim 2). We will also assess the preclinical potential of the model for testing preventive (Aim 2) and therapeutic (Aim 3) interventions against STIs. For these studies, we will leverage the full force of state-of-the-art microscopic and RNA-sequencing methodologies to identify and characterize microbiota specific alterations of structural and host epithelial homeostasis and expand our understanding of the triangular relationship between the host, the microbiota and C. trachomatis.