E. coli virulence gene expression during clinical UTIs in women

 描述（由申请人提供）：泌尿道是细菌感染的最常见部位之一。大肠杆菌是迄今为止最常见的感染该网站的物种。大多数关于尿路致病性E.大肠杆菌（UPEC）毒力基因来自体外研究或泌尿道感染（UTI）的鼠模型。为了解决这个问题，我们测量了E.大肠杆菌的尿液中收集和稳定的妇女提出了简单的尿路感染。这些新的RNAseq数据使我们能够专注于人类感染期间最高表达的毒力机制。我们的长期研究目标是了解UPEC如何在人体尿路定植，避免免疫反应，并损害宿主。在此资助期间的目标是确定致病的毒力基因被发现在人类宿主中特异性上调的贡献。我们的中心假设，即UPEC菌株的毒力是其粘附，铁获取，毒素产生和特定代谢物转运能力的总和，得到了我们对五名因膀胱炎症状而参加密歇根大学大学健康服务诊所的女性在UTI期间UPEC全球基因表达模式的测量的支持。这项工作的基本原理是，一旦我们确定了人类UTI期间表达最高的毒力基因，我们就可以集中精力针对这些特定目标进行干预和预防。我们将测试我们的中心假设，并完成我们的目标，通过执行两个具体的目标：1）确定代表性的转录组尿路致病性大肠杆菌。大肠杆菌在人类尿路感染过程中的作用; 2）确定新发现的在大肠杆菌中上调的毒力决定簇的发病机制。大肠杆菌感染妇女尿路感染。进行这些目标的预期结果将是一个精确的评估全球的基因表达和宿主特异性的毒力基因在感染妇女，但不是在尿液或丰富的培养基中的体外培养过程中上调。这些研究的积极影响将是巨大的。我们将精确地量化UPEC基因在其他健康女性感染过程中的表达。我们将确定新发现的致病因子在尿路感染中的作用机制。杆菌我们将 也了解哪些毒力决定因素都存在，并在简单的人类UTI表达，以及它们的表达程度。了解细菌用于定植人类尿路的毒力因子，避免免疫反应，并损害宿主，将为预防复发性UTI妇女和易患首次UTI的妇女的这种公共卫生灾难打开大门。

 DESCRIPTION (provided by applicant): The urinary tract is among the most common sites of bacterial infection and E. coli is by far the most common species infecting this site. Most data regarding expression of uropathogenic E. coli (UPEC) virulence genes have come from in vitro studies or the murine model of urinary tract infection (UTI). To remedy this, we have measured global gene expression from E. coli in urine collected and stabilized immediately from women presenting with uncomplicated UTI. These new RNAseq data allow us to focus on the most highly expressed virulence mechanisms active during human infection. Our long term research goal is to understand how UPEC colonize the human urinary tract, avoid the immune response, and damage the host. The objective during this funding period is to determine the contribution to pathogenesis of the virulence genes found to be specifically upregulated in the human host. Our central hypothesis, that the virulence of a UPEC strain is the sum of its capacity for adherence, iron acquisition, toxin production and specific metabolite transport, is supported by our measurements of global gene expression patterns of UPEC during UTI in five women attending the University Health Service Clinic at the University of Michigan for the symptoms of cystitis. The rationale for the proposed work is that once we identify the most highly expressed virulence genes during UTI in humans, we can focus efforts on intervention and prevention directed toward these specific targets. We will test our central hypothesis and complete our objectives by carrying out two specific aims: 1) Determine the representative transcriptome for uropathogenic E. coli during urinary tract infection in humans; and 2) Determine the mechanism of pathogenesis for newly discovered virulence determinants upregulated in E. coli infecting women with urinary tract infection. The expected outcomes of conducting these aims will be a precise assessment of global gene expression and host-specific virulence genes upregulated during infection in women, but not during in vitro culture in urine or rich medium. The positive impact of these studies will be substantial. We will precisely quantify UPEC gene expression during infection of otherwise healthy women. We will determine the mechanisms of action of the newly identified virulence factors active during infection of the urinary tract by E. coli. We will also understand which virulence determinants are both present and expressed during uncomplicated human UTI, and the degree to which they are expressed. Understanding the virulence factors used by the bacterium to colonize the human urinary tract, avoid the immune response, and damage the host will open the door to preventing this public health scourge in women with recurrent UTI and those susceptible to their first UTI.