Identification of key players mediating internalization of Trichomonas vaginalis extracellular vesicles by host cells and parasite adherence and survival in vivo

宿主细胞介导阴道毛滴虫细胞外囊泡内化的关键参与者的鉴定以及寄生虫在体内的粘附和存活

• 批准号: 10410401
• 负责人: Patricia Jean Johnson
• 金额: $ 65.6万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-02 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10410401
• 关键词: Adherence; Affect; American; Annual Reports; Antigen Presentation; Binding; Biochemical; Case Study; Cell Communication; Cell physiology; Cells; Centers for Disease Control and Prevention (U.S.); Cervicitis; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Communicable Diseases; Communication; Contracts; Data; Development; Disease; Down-Regulation; Drug resistance; Future; Glycoside Hydrolases; Goals; HIV; Health; Helminths; Heparan Sulfate Proteoglycan; Heparitin Sulfate; Homeostasis; Human; Immune; Immune response; In Vitro; Incidence; Infection; Inflammatory; Knock-out; Knowledge; Lead; Learning; Leishmania; Ligands; Malignant neoplasm of cervix uteri; Malignant neoplasm of prostate; Mammalian Cell; Mass Spectrum Analysis; Mediating; Membrane; Molecular; Neonatal Mortality; Neoplasm Metastasis; Outcome; Parasites; Parasitic infection; Pathogenesis; Pelvic Inflammatory Disease; Persons; Pharmaceutical Preparations; Plasmodium; Play; Pregnancy Complications; Process; Property; Proteins; Proteomics; RNA; Reporting; Research; Risk; Role; Severities; Sexually Transmitted Diseases; Site; Testing; Therapeutic; Transferase; Trichomonas Infections; Trichomonas vaginalis; Trypanosoma; Urethritis; Urogenital Cancer; Vaccine Design; Vaginitis; Vesicle; adverse pregnancy outcome; cytokine; design; exosome; extracellular; extracellular vesicles; host colonization; human pathogen; immunoregulation; in vivo; insight; male; mouse model; neglect; novel; novel therapeutic intervention; pathogen; receptor; response; transmission process; uptake; urogenital tract; vaccine candidate

Project Summary/Abstract The unicellular parasite Trichomonas vaginalis is responsible for the most prevalent, non-viral, sexually- transmitted infection worldwide, with approximately ¼ billion people contracting trichomoniasis annually. Trichomoniasis is the most common parasitic infection in the US, with an annual incidence estimated at ~5 million cases. Nevertheless, this parasite is vastly understudied. As such, T. vaginalis was classified by the Center of Disease Control and Prevention as a neglected infection in the US in 2014. In addition to being a common cause of vaginitis, trichomoniasis is associated with adverse inflammatory sequelae, that can contribute to pregnancy complications and neonatal mortality, the spread of HIV, and increased metastasis of urogenital cancers. The incidence of infection, the growing recognition that T. vaginalis is associated with long-term health consequences and an increase in the number of drug resistant clinical isolates of T. vaginalis underscore the need to develop new chemotherapeutic and vaccine design strategies. A much better understanding of processes involved in infectivity and pathogenesis, such as those proposed here, will be imperative to achieve these goals. Several years ago we discovered that T. vaginalis secretes small, membrane-bound extracellular vesicles (EVs), that mediate host:parasite interactions. We have shown that parasite proteins are transferred to host cells via EVs, which in turn, modulates both parasite adherence to host cells and the host cell responses. Host:pathogen cross- talk mediated by EVs likely contributes to parasite colonization of the host and down-regulation of cytokines that elicit immune cells to the site of infection. This proposal focuses on the molecular and cellular mechanisms used for host cell internalization of EVs: a process required for EV-mediated communication between the parasite and host. We will also examine the effect of EVs on the survival of parasites in vivo using a newly-developed mouse model. To this end, we propose to: characterize biochemical properties of an EV ligand (Tv 4-alpha- glucanotransferase) that binds host cell heparan sulfate proteoglycans and drives EV internalization by host cells (Aim 1); isolate and identify EV receptor(s) on the host cell and test whether the receptor(s) are required for EV internalization (Aim 2) and to identify EV proteins involved in host cell internalization and test whether EVs affect parasite survival during early stage infection in vivo using isogenic T. vaginalis strains that differ in host cell adherence (Aim 3). We will uncover biochemical and cellular mechanisms that promote parasite infection and will reveal whether our in vitro findings supporting a role for EVs in host cell colonization are confirmed in vivo. Novel mechanisms are likely to be found, as very little mechanistic data on the interaction or uptake of any parasite-derived EV with host cells have been reported. In addition to expanding our knowledge of host:pathogen interactions, these studies will increase our overall knowledge of how EVs mediate cell:cell communication and will contribute to a better understanding of the role of EVs in infectious diseases. These findings could also enable future development of new therapeutic approaches.

项目概要/摘要 单细胞寄生虫阴道毛滴虫是最流行的非病毒性性病的罪魁祸首。 滴虫病在全球范围内传播，每年约有 1/4 亿人感染滴虫病。 毛滴虫病是美国最常见的寄生虫感染，年发病率估计约为 500 万例 案例。然而，这种寄生虫的研究还远远不够。因此，阴道毛滴虫被中心分类为 2014 年，疾病控制和预防在美国被视为一种被忽视的感染。除了是一个常见原因之外 阴道炎中，滴虫病与不良炎症后遗症有关，可能导致怀孕 并发症和新生儿死亡率、艾滋病毒传播以及泌尿生殖系统癌症转移增加。这 感染的发生率，人们越来越认识到阴道毛滴虫与长期健康后果有关 阴道毛滴虫耐药临床分离株数量的增加强调了开发 新的化疗和疫苗设计策略。更好地理解所涉及的流程 传染性和发病机制，例如这里提出的那些，对于实现这些目标至关重要。一些 几年前，我们发现阴道毛滴虫分泌小的、膜结合的细胞外囊泡（EV）， 介导宿主：寄生虫相互作用。我们已经证明寄生虫蛋白通过 EV 转移到宿主细胞， 这反过来又调节寄生虫对宿主细胞的粘附和宿主细胞的反应。宿主：病原体交叉 由 EV 介导的对话可能有助于寄生虫在宿主中的定殖以及细胞因子的下调 诱导免疫细胞到达感染部位。该提案重点关注所使用的分子和细胞机制 EV 的宿主细胞内化：EV 介导的寄生虫和细胞之间的通讯所需的过程 主持人。我们还将使用新开发的小鼠来研究 EV 对体内寄生虫存活的影响 模型。为此，我们建议：表征 EV 配体（Tv 4-α- 葡聚糖转移酶）结合宿主细胞硫酸乙酰肝素蛋白聚糖并驱动宿主细胞 EV 内化 （目标 1）；分离并鉴定宿主细胞上的 EV 受体，并测试该受体是否是 EV 所必需的 内化（目标 2）并鉴定参与宿主细胞内化的 EV 蛋白并测试 EV 是否影响 使用宿主细胞不同的同基因阴道毛滴虫菌株进行体内早期感染期间寄生虫的存活 坚持（目标 3）。我们将揭示促进寄生虫感染的生化和细胞机制 将揭示我们支持 EV 在宿主细胞定植中的作用的体外研究结果是否在体内得到证实。 很可能会发现新的机制，因为关于任何相互作用或吸收的机械数据很少 已经报道了带有宿主细胞的寄生虫衍生的EV。除了扩大我们对宿主：病原体的了解 相互作用，这些研究将增加我们对电动汽车如何介导细胞间通讯和 将有助于更好地了解电动汽车在传染病中的作用。这些发现还可以 促进新治疗方法的未来发展。