EBPA-FIBROGEN INTERACTION IN ENTEROCOCCUS FAECALIS CAUTI

描述（由申请方提供）：导管相关尿路感染（CUTI）是最常见的医院感染之一，如果不治疗，可导致严重并发症，包括菌血症和死亡。粪肠球菌（Enterococcus faecalis）是引起大肠杆菌感染的主要病原体，其在宿主体内的粘附和持续能力沿着其多重抗生素耐药性使得其难以预防和治疗。粪肠球菌可形成生物膜并生长，尽管在肠内感染期间有强烈的炎症反应。E.粪便粘附、在膀胱中生长、形成生物膜，并且生物膜在膀胱炎中持续存在的重要性还没有得到很好的理解。本项目将使用最近优化的E. faecalis faecalis pneumonia TI了解E.粪便Epb菌毛和纤维蛋白原有助于疾病。要解决的重要问题包括如何结合纤维蛋白原的菌毛的EbpA亚基的分子分析和这种相互作用的重要性，以APOPTI。体外生物膜形成缺陷的突变体完全能够形成 这表明标准生物膜模型不能再现相关的体内条件。该项目将评估一种新的补充纤维蛋白原的尿液生物膜模型，以确定该模型中生物膜所需的基因是否也是小鼠ESTTI中生物膜所需的基因，并将测试生物膜在引起疾病中的重要性。最后，我们有数据表明，EbpA亚基为基础的疫苗保护鼠抗纤溶酶原抑制剂，免疫动物产生抗体，阻断EbpA-纤维蛋白原结合。该项目将测试各种EbpA亚结构域和肽疫苗与使用其他菌毛亚单位的制剂相比的保护效力。结合免疫动物血清的被动转移和抗体应答的表征，将有可能特异性地测试保护机制是否依赖于阻断EbpA-纤维蛋白原结合。该项目所产生的数据将提供重要的新的见解的发病机制，直接应用到新的治疗方式的发展。.

DESCRIPTION (provided by applicant): Catheter-associated urinary tract infections (CAUTIs) are one of the most common nosocomial infections and if untreated can lead to serious complications including bacteremia and death. Enterococcus faecalis is a leading causative agent of CAUTI and its ability to adhere and persist within the host along with its multiple antibiotic resistances makes it difficult to prevent and treat. Furthermore, E. faecalis can form biofilm and grow despite a robust inflammatory response during CAUTI. The molecular details of how E. faecalis adheres, grows in the bladder, forms biofilm and the importance of biofilm in persistence in CAUTI are not well understood. This project will use a recently optimized model of E. faecalis CAUTI to understand how interactions between the E. faecalis Epb pilus and fibrinogen contribute to disease. Important questions to be addressed include a molecular analysis of how the EbpA subunit of the pilus binds to fibrinogen and the importance of this interaction to CAUTI. Mutants defective for biofilm formation in vitro are fully capable of forming biofilm in murine CAUTI, suggesting that standard biofilm models do not reproduce relevant in vivo conditions. This project will evaluate a new model of fibrinogen-supplemented urine biofilms to determine if genes required for biofilm in this model are also required for biofilm in murine CAUTI and will test the importance of biofilm in causing disease. Finally, we have data to suggest that an EbpA subunit-based vaccine protects against murine CAUTI and that immunized animals generate antibody that blocks EbpA-fibrinogen binding. The project will test the protective efficacy of various EbpA sub-domain and peptide vaccines in comparison to formulations that use other pilus sub- units. Combined with passive transfers of sera from immunized animals and characterization of antibody responses, it will be possible to specifically test whether the mechanism of protection depends on blocking EbpA-fibrinogen binding. The data generated by this project will provide significant new insights into the pathogenesis of CAUTI with direct application to the development of new modalities of therapy. .