The function of chemotactic signal transduction during colonization and disease

我们提出的研究重点是确定TlpA和TlpB化学受体的作用机制， 在引起溃疡的细菌幽门螺杆菌的发病机制中起重要作用。这些受体 调制H.幽门引起的炎症然而，在我们的理解中存在着一个根本的差距， TlpA和TlpB信号，这些受体如何感知它们的配体，它们如何进行信号转导， 它们如何促进发病。这一差距的继续存在使我们无法充分了解 阁下于幽门螺杆菌的致病机制，并从长远来看，阻碍这些过程，使创造 抗H.幽门相关疾病全世界和美国有数百万人感染H。 幽门螺杆菌和遭受其相关的疾病-溃疡和胃癌。胃癌是第二大病因 全球癌症死亡人数的一半。H.幽门螺杆菌在这里停留基于最近的研究表明，H。幽门螺杆菌发病率 稳定在发达国家。此外，目前治疗H.幽门螺杆菌感染失败， BLE频率，例如，美国最近的估计发现，20-25%的感染者是 目前的治疗方法无法治愈迫切需要新的药物靶点。具体目标 本申请的目的是剖析TlpA和TlpB信号转导及其在胃疾病中的作用。我们的中央卫生- 假设TlpA和TlpB从特异性配体传递信息以影响细菌-宿主相互作用， 促炎基因表达，进而导致宿主炎症。我们的假设是从 使用小分子阵列鉴定TlpA特异性新配体的初步数据，开发关键试剂 用于分析TlpA和TlpB信号转导，确定TlpA和TlpB在炎症中的作用，以及 提出了新的分析H.幽门螺杆菌在胃的设置。在目标1中，我们确定了 TlpA和TlpB配体结合和信号转导，使用纯化蛋白的体外结合试验，体外 趋化性信号转导分析和完整H.幽门趋化性测定。在目标2中，我们确定 TlpA和TlpB调节炎症的机制，分析炎症反应的性质 由tlpA或tlpB突变体引起。此外，我们还将探讨TlpA和TlpB突变体是否具有 异常的宿主细胞相互作用和分布。最后，我们研究了主机参数 利用代谢组学分析胃中营养分布的感染过程的变化， 最先进的类器官培养系统这项研究是创新的，因为它将创造新的 关于细菌致病过程中趋化性功能的知识，及其最新技术水平的应用 接近。这项拟议中的研究意义重大，因为它解决了趋化性， 重要的许多病原体，并特别关注一种细菌，造成猖獗的疾病，但 我们正在失去抗生素的效力。这项研究产生的长期结果可能会提供 这些见解将有助于创造新的药物来对抗H。幽门相关疾病

Our proposed research focuses on defining the mechanism of action of the TlpA and TlpB chemoreceptors that play fundamental roles in pathogenesis of the ulcer-causing bacterium Helicobacter pylori. These receptors modulate H. pylori-induced inflammation. There is a fundamental gap, however in our understanding of the TlpA and TlpB signals, of how these receptors sense their ligands, how they perform signal transduction, and how they promote pathogenesis. Continued existence of this gap prevents us from gaining a full understanding of H. pylori's pathogenic mechanisms and, in the long term, thwarting these processes to enable the creation of new drugs against H. pylori-related disease. Millions of people worldwide and in the U.S. are infected by H. pylori and suffer from its associated diseases—ulcers and gastric cancer. Gastric cancer is the second cause of cancer deaths worldwide. H. pylori is here to stay based on recent studies that show H. pylori incidence has stabilized in the developed world. Furthermore, current therapies to cure H. pylori infection fail with unaccepta- ble frequency, e.g., recent estimates in the United States have found that 20-25% of infected individuals are not cured by the current therapeutic regime. New drug targets are desperately needed. The specific objective of this application is to dissect TlpA and TlpB signal transduction and its role in gastric disease. Our central hy- pothesis is that TlpA and TlpB transduce information from specific ligands to affect bacterial-host interactions, proinflammatory gene expression, and in turn, host inflammation. Our hypothesis has been formulated from preliminary data using small molecule arrays to identify specific new ligands of TlpA, developing key reagents for analyzing TlpA and TlpB signal transduction, defining the roles of TlpA and TlpB in inflammation, and de- veloping new assays for analyzing H. pylori in the gastric setting. In Aim 1, we determine the mechanism of TlpA and TlpB ligand binding and signal transduction, using in vitro binding assays with purified protein, in vitro chemotaxis signal transduction assays, and intact H. pylori chemotaxis assays. In Aim 2, we determine the mechanism by which TlpA and TlpB modulate inflammation, analyzing the nature of the inflammatory response provoked by tlpA or tlpB mutants. In addition, we will explore the possibility that TlpA and TlpB mutants have abnormal host cell interactions and distribution. Lastly, we investigate the hypothesis that host parameters change of the course of an infection using metabolomics to analyze nutrient distribution in the stomach and state-of-the art organoid culture systems. The proposed research is innovative in that it will create new knowledge about the functions of chemotaxis during bacterial pathogenesis, and it its use of state of the art approaches. The proposed research is significant because it addresses chemotaxis, a fundamental property important to many pathogens, and focuses specifically on a bacterium that causes rampant disease but for which we are losing antibiotic efficacy. The long-term outcomes generated by this research are likely to provide insights that will enable creation of new drugs against H. pylori-related disease.