Molecular T. vaginalis-host interactions in relevance to inflammatory sequelae

描述（由申请人提供）：滴虫病是最常见的非病毒性性传播感染（STI），每年影响全球1.8亿多人和800 - 1000万美国人。它使妇女易患早产、低出生体重、宫颈癌、严重炎症和增加感染艾滋病毒-1的风险。在大约一半的妇女中，感染是无症状的，并且经常复发，没有持久的免疫力，这表明先天免疫防御的重要性。分离纯化了寄生虫T.阴道寄生虫（TV）脂磷酸聚糖（LPG）的研究，使我们能够研究寄生虫和复杂的阴道环境之间的新的分子相互作用。LPG是一种糖基磷脂酰肌醇样锚定分子，与其他GPI样寄生分子不同，它不含甘露糖，具有聚-N-乙酰乳糖胺重复序列。我们是第一个证明LPG在寄生虫粘附和向正常人阴道上皮细胞发出信号中起关键作用的人。我们最新的新发现表明，LPG结合阴道上皮细胞表达的半乳糖凝集素，并可能与特定的细菌性阴道病（BV），这是一种已知的增加对HIV感染的易感性的条件阴道微生物区系成分协同作用。我们已经确定了LPG的结构域，神经酰胺磷脂酰肌醇聚糖核心（CPI-GC）与m/z 8695.5，作为一个潜在的半乳糖凝集素配体负责阴道和宫颈上皮细胞的促炎激活。我们假设T.迷走神经LPG，特别是其PI-GC，通过结合具有生殖器粘膜和宿主免疫系统中相反功能的半乳糖凝集素来调节宿主免疫炎症环境，并且这些事件可能由BV相关微生物群促进。为了验证这一假设，我们建议使用一个生理相关的体外模型系统，并将我们的实验结果与一个前瞻性收集的女性队列中的免疫反应相关联，这些女性在感染TV和HIV-1之前和之后有BV和无BV。我们的具体目标是：1）确定半乳糖凝集素作为阴道天然免疫调节剂和T细胞受体的作用。本研究的目的是：1）进一步研究阴道毛滴虫病和细菌性阴道病的LPG，并鉴定在正常和BV相关微生物区系中宫颈阴道上皮细胞中的相关信号通路; 2）进一步阐明LPG的生化结构和负责半乳糖凝集素结合和信号传导的CPI-GC亚结构域; 3）鉴定和验证并发滴虫病和细菌性阴道病中阴道免疫力改变的分子模式，这可能增加HIV感染风险。该研究将有助于加深对T.流浪汉它将阐明与滴虫病和BV相关的HIV-1风险增加的潜在机制，验证阴道免疫失调的诊断和预后生物标志物，并为新的预防和治疗策略铺平道路。公共卫生相关性：阴道毛滴虫病是世界上最常见的非病毒性性传播感染（滴虫病）之一，它使妇女容易感染HIV-1、早产和癌症;全世界每年有超过1.8亿人感染，其中包括800万至1000万美国人。随着对寄生虫的抗生素耐药性的上升，基于分子医学进展的新预防策略的开发至关重要。这项研究的目的是“分子T。与炎症后遗症相关的阴道-宿主相互作用”是揭示与炎症症状和感染易感性相关的寄生虫-宿主相互作用的分子机制。

DESCRIPTION (provided by applicant): Trichomoniasis is the most common non-viral sexually transmitted infection (STI) affecting annually over 180 million people worldwide and 8-10 million Americans. It predisposes women to pre-term delivery, low birth weight, cervical cancer, severe inflammation, and increased risk of HIV-1 infection. In about half of the women the infection is asymptomatic and is often recurrent with no lasting immunity suggesting the importance of the innate immune defenses. The isolation and purification of the predominant cell surface glycoconjugate of the parasite, the T. vaginalis (TV) lipophosphoglycan (LPG), has allowed us to study novel molecular interactions between the parasite and the complex vaginal environment. LPG is a glycosylphosphatidyl inositol-like anchored molecule, which unlike other GPI-like parasitic molecules, contains no mannose and has poly-N-acetyllactosamine repeats. We were the first to show that LPG plays a key role in the parasite adhesion and signaling to normal human vaginal epithelial cells. Our latest novel findings suggest that LPG binds galectins expressed by vaginal epithelial cells and may synergize with selected vaginal microflora components specific for bacterial vaginosis (BV), which is a condition known to increase susceptibility to HIV infection. We have identified the structural domain of LPG, the ceramide phosphatidyl-inositol-glycan core (CPI-GC) with m/z 8695.5, as a potential galectin ligand responsible for proinflammatory activation of vaginal and cervical epithelial cells. We hypothesize that T. vaginalis LPG, especially its PI-GC, modulate the host immunoinflammatory environment via binding galectins with opposing functions in the genital mucosa and host immune system and that these events may be facilitated by BV-associated microflora. To test this hypothesis we propose to use a physiologically relevant in vitro model system and correlate our experimental findings with immune responses in a prospectively collected cohort of women with and without BV followed before and after infection with TV and HIV-1. Our specific aims are to: 1) define the roles of galectins as vaginal innate immunity modulators and host receptors for T. vaginalis LPG and identify related signaling pathways operating in the cervicovaginal epithelial cells in the context of normal and BV-associated microflora; 2) elucidate further the biochemical structure of LPG and the CPI-GC subdomains responsible for galectin binding and signaling; and 3) identify and validate molecular patterns of altered vaginal immunity in concurrent trichomoniasis and bacterial vaginosis that may enhance HIV infection risk. The proposed research will expand the understanding of the immune evasion by T. vaginalis. It will elucidate mechanisms underlying increased HIV-1 risk in relations to trichomoniasis and BV, validate diagnostic and prognostic biomarkers of vaginal immune dysregulation and pave the way to novel prevention and treatment strategies. PUBLIC HEALTH RELEVANCE: Trichomonas vaginalis is one of the most common non-viral sexually transmitted infections (trichomoniasis) in the world, which predisposes women to HIV-1 infection, preterm delivery and cancer; over 180 million people world-wide, including 8-10 million Americans become infected annually. With antibiotic resistance to the parasite on the rise, the development of novel prevention strategies based on the advances of molecular medicine is critical. The objective of this study entitled "Molecular T. vaginalis-host interactions in relevance to inflammatory sequelae" is to unveil molecular mechanisms of parasite-host interactions associated with inflammatory symptoms and susceptibility to infection.