MOLECULAR BASIS OF E. COLI ADHESINS IN BLADDER DISORDERS

项目概要/摘要： 尿路感染（UTI）导致相当大的发病率和医疗保健费用。的 最常见的原因是革兰氏阴性菌，尿路致病性大肠杆菌 （UPEC）。人类感染的特征是菌尿和细胞因子的释放， 脱落细胞和多形核白细胞（PMN）进入尿中。这些临床 疾病的表现都在小鼠中可见。使用qRT-PCR，微阵列分析， 显微镜和免疫组织化学，我们进一步描述了反应， UPEC感染。我们已经证明，1型菌毛介导的UPEC结合， 膀胱上皮细胞的侵袭增强Toll样受体（TLR）4介导的 信号传导并导致参与细胞分化的基因的快速上调， 增殖和立即早期反应，促炎反应，凋亡， 应激反应、信号转导、细胞-细胞接触和代谢变化。此外，本发明还 我们已经证明，基质细胞和造血细胞上的TLR 4介导的信号传导是 这是有效清除细菌所必需的。造血细胞包括巨噬细胞 (M)树突状细胞（DC）、粒细胞以及B和T细胞。在本提案中，我们描述了 实验建立在我们以前的工作，以了解主机进程的重要性， 确定病原体和正常无菌的微生物之间相遇的结果， 宿主泌尿道。我们将描述宿主对UPEC的反应，包括UPEC的动力学。 感染膀胱内细胞因子的产生，免疫浸润的层次结构， 细胞，以及免疫细胞和感染之间的早期相互作用的真实的可视化 细菌我们还将通过以下方式加深对尿路感染和宿主反应的理解： 表征宿主对两种革兰氏阳性细菌的反应，所述革兰氏阳性细菌也引起UTI， 人、金黄色葡萄球菌和粪肠球菌。不同寄主 革兰氏阴性菌和革兰氏阴性菌之间的反应机制和细菌嗜性， 阳性UTI可能对疾病症状、进展和治疗有影响。 使用小鼠突变背景和细胞及细胞因子耗竭实验，我们将 研究宿主免疫细胞和防御分子在炎症，细菌， 清除、储库维持以及上皮脱落和再生。详细 了解宿主对UTI的反应可能有助于阐明新的和更好的 评估、治疗和预防这些常见感染的方法。项目叙述/相关性： UTI经常发生在其他健康的女性中，估计约2.5美元 每年的医疗费用高达10亿美元。在这个建议中，我们描述了实验，以扩大 我们通过表征可溶性介质和宿主免疫功能来了解UTI 参与宿主对UTI最常见原因（尿路致病性）的反应的细胞 大肠杆菌）和两种革兰氏阳性菌（金黄色葡萄球菌和 粪肠球菌）。更好地理解参与的宿主因素 确定感染的结果是需要更好地诊断，治疗和预防这一点， 常见病

Project Summary / Abstract: Urinary tract infections (UTIs) result in considerable morbidity and health care costs. The most common cause is the Gram-negative bacteria, uropathogenic Escherichia coli (UPEC). Human infections are characterized by bacteriuria and the release of cytokines, exfoliated cells, and polymorphonuclear leukocytes (PMN) into the urine. These clinical manifestations of disease are all seen in mice. Using qRT-PCR, microarray analyses, microscopy, and immunohistochemistry, we have further described the response to UPEC infection. We have demonstrated that type 1 pili-mediated UPEC binding to and invasion of bladder epithelial cells potentiates toll-like receptor (TLR) 4-mediated signaling and results in rapid upregulation of genes involved in cell differentiation, proliferative and immediate-early responses, pro-inflammatory responses, apoptosis, stress responses, signal transduction, cell-cell contacts, and metabolic changes. Further, we have shown that TLR4-mediated signaling on both stromal and hematopoietic cells is required for efficient clearance of bacteria. Hematopoietic cells include macrophages (M), dendritic cells (DC), granulocytes, and B and T cells. In this proposal we describe experiments to build on our previous work to understand host processes important in determining the outcome of an encounter between pathogens and the normally sterile host urinary tract. We will delineate the host response to UPEC, including the kinetics of cytokine production within the infected bladder, the hierarchy of infiltration of immune cells, and real time visualization of early interactions between immune cells and infecting bacteria. We will also broaden our understanding of UTIs and host response by characterizing the host response to two Gram-positive bacteria that also cause UTIs in humans, Staphylococcus saprophyticus and Enterococcus faecalis. Differing host response mechanisms and bacterial tropisms between Gram-negative and Gram- positive UTIs may have implications for disease symptoms, progression, and treatment. Using mouse mutant backgrounds and cell and cytokine depletion experiments, we will examine the roles of host immune cells and defense molecules in inflammation, bacterial clearance, reservoir maintenance, and epithelial exfoliation and regeneration. A detailed understanding of the host response to UTIs may lead to elucidation of new and better ways to evaluate, treat, and prevent these common infections. Project Narrative / Relevance: UTIs occur frequently in otherwise healthy women and result in an estimated ~$2.5 billion annually in health care costs. In this proposal we describe experiments to broaden our understanding of UTIs by characterizing the soluble mediators and host immune cells involved in the host response to the most common cause of UTI (uropathogenic Escherichia coli) and two Gram-positive bacteria (Staphylococcus saprophyticus and Enterococcus faecalis). A better understanding of the host factors involved in determining the outcome of infection is needed to better diagnosis, treat and prevent this common disease.