MOLECULAR BASIS OF E. COLI ADHESINS IN BLADDER DISORDERS

项目摘要/摘要： 尿路感染(UTI)导致相当大的发病率和医疗费用。这个 最常见的原因是革兰氏阴性杆菌，泌尿系致病性大肠埃希菌 (UPEC)。人类感染的特征是菌尿和细胞因子的释放， 脱落的细胞和多形核白细胞(PMN)进入尿液。这些临床 疾病的表现在老鼠身上都能看到。使用qRT-PCR，微阵列分析， 显微镜和免疫组织化学，我们已经进一步描述了对 UPEC感染。我们已经证明了1型菌毛介导的UPEC与和 膀胱上皮细胞侵袭增强Toll样受体(TLR)4介导 信号传递并导致参与细胞分化的基因迅速上调， 增殖性和即刻早期反应，促炎反应，细胞凋亡， 应激反应、信号转导、细胞-细胞接触和代谢变化。此外， 我们已经证明，TLR4介导的基质细胞和造血细胞上的信号是 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、B细胞和T细胞。在这份提案中，我们描述了 在我们之前工作的基础上进行实验，以了解主机进程在 确定病原体与正常无菌者相遇的结果 宿主尿路。我们将描述宿主对UPEC的反应，包括 细胞因子在感染膀胱内的产生，免疫的层级渗透 细胞，以及免疫细胞和感染之间早期相互作用的实时可视化 细菌。我们还将通过以下方式扩大我们对尿路感染和东道主反应的理解 描述宿主对两种革兰氏阳性细菌的反应，这两种细菌也会导致尿路感染 人类、腐生葡萄球菌和粪肠球菌。不同的主机 革兰氏阴性杆菌和革兰氏阴性杆菌的反应机制和细菌趋向性 尿路感染阳性可能对疾病症状、进展和治疗有影响。 利用小鼠突变背景和细胞和细胞因子耗尽实验，我们将 检查宿主免疫细胞和防御分子在炎症、细菌 清除，水库维护，上皮剥落和再生。一个详细的 了解宿主对尿路感染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。项目说明/相关性： 尿路感染在其他方面健康的女性中经常发生，估计导致约2.5美元 每年的医疗保健费用为10亿美元。在这份提案中，我们描述了扩大 我们对尿路感染的可溶性介质和宿主免疫的认识 参与宿主对尿路感染(尿路感染)最常见原因反应的细胞 大肠埃希菌)和两株革兰氏阳性菌(腐生葡萄球菌和 粪肠球菌)。更好地了解涉及的宿主因素 为了更好地诊断、治疗和预防这种情况，需要确定感染的结局。 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.