Extracellular vesicles miRNA cargo induces inflammation during chlamydial infection

摘要 沙眼衣原体是世界上最常见的性传播细菌感染，尤其是 流行于青少年和青壮年。感染的一个主要后果是持续性炎症。 以及对生殖器官的渐进性损害，对女性来说，这可能导致严重的盆腔炎 疾病和不孕不育。一些研究表明，先天免疫细胞、CD8 T细胞和炎性细胞 信号通路(干扰素-β、白介素1β和肿瘤坏死因子-α)在疾病转归中的作用。我们的长期目标是确定如何 衣原体感染影响宿主细胞过程以促进细菌复制以及这些相互作用是如何 可能会导致疾病。 以前的报告表明，在感染过程中释放细胞外小泡(EV)，并已显示 含有DNA、RNA、miRNA、蛋白质和微生物成分。确定肠道病毒在宿主-病原体中的相关性 相互作用还处于研究的早期阶段，还需要更多的工作来了解生物相关性 在感染期间EV的数量。在细菌感染领域还没有回答的更大的问题 在EV生物学方面：(1)EVS是否影响免疫细胞功能和炎症反应；(2)EVS是否释放 肠道病毒有助于细菌入侵，(3)肠道病毒在疾病转归中的作用是什么，以及(4) EV的组成因病原体的类型而异。了解这些问题将决定电动汽车在 宿主防御和疾病结局。我们的初步数据清楚地表明EV从衣原体感染的体内释放出来 细胞，以及在EVS中存在miRNA货物。据我们所知，我们是第一个证明电动汽车 衣原体感染时释放的病毒含有miRNAs。我们的建议是确定EV-miRNA货物的作用 在炎症和疾病转归中的作用，并描述它们在细菌入侵中的作用。根据我们的初步调查 数据我们假设EV-miRNAs参与了炎症和病理的诱导 衣原体感染。我们用两个特定的目标来检验我们的假设：(1)确定EV相关的作用 MiRNAs在衣原体感染的炎症和TLR7激活中的作用以及(2)确定EVS在 衣原体感染小鼠模型的建立。深入了解EV相关miRNAs的作用在以下方面具有影响力 了解感染后炎症反应的整个过程。此外，定义体内的 EV相关miRNAs的功能在衣原体感染相关研究中具有创新性和新颖性。 我们的高风险和高回报计划的完成将决定EV是否会引发炎症 通过TLR7在衣原体感染期间传播，还将加强对EV生物学的一般了解。洞察 参与细菌存活、炎症和免疫反应的机制将有助于疫苗 发展和可能的治疗选择。

ABSTRACT Chlamydia trachomatis is the most common sexually-transmitted bacterial infection in the world, and is especially prevalent among adolescents and young adults. A major consequence of infection is persistent inflammation and evolving damage to the reproductive organs, which in females can result in severe pelvic inflammatory disease and infertility. Several studies have shown the role for innate immune cells, CD8 T cells and inflammatory signaling pathways (IFN-β, IL-1β, and TNF-α,) in disease outcome. Our long-term goals are to identify how Chlamydia infection impacts host cellular processes to facilitate bacterial replication and how these interactions may result in disease. Previous reports indicated release of extracellular vesicles (EVs) during infections and have been shown to contain DNA, RNA, miRNA, protein, and microbial components. Determining EVs relevance in host-pathogen interactions is at an early stage of investigation and more work is needed to understand the biological relevance of EVs during infection. The bigger questions that have not been answered in the field of bacterial infections or in EV biology are: (1) Do the EVs impact immune cell function and inflammatory response, (2) Does the release of EVs help in bacterial invasion, (3) What is the role of EVs in the disease outcome, and (4) Does the composition of EVs vary with the type of pathogen?. Understanding these questions will determine EVs role in host defense and disease outcome. Our preliminary data clearly shows EVs release from Chlamydia-infected cells, and presence of miRNA cargo in EVs. To the best of our knowledge we are the first to show that EVs released during Chlamydia infection contain miRNAs. Our proposal is to determine the role of EV-miRNA cargo in inflammation and disease outcome and delineate their role in bacterial invasion. Based on our preliminary data we hypothesize that EV-miRNAs are involved in the induction of inflammation and pathology during Chlamydia infection. We test our hypothesis with two specific aims: (1) Determine the role of EV-associated miRNAs in inflammation and TLR7 activation during Chlamydia infection and (2) Identify the role of EVs in a mouse model of Chlamydia infection. Insight into the role of EV-associated miRNAs is impactful in terms of understanding the overall process of inflammatory response to infection. Furthermore, defining the in vivo function of EV-associated miRNAs is innovative and novel for studies related to Chlamydia infection. Completion of our high risk and high reward proposal will determine whether EVs induce inflammation via TLR7 during Chlamydia infection and will also enhance general understanding of EV biology. Insight into mechanisms involved in bacterial survival, inflammation and immune response would help in vaccine development and possibly therapeutic options.