The function of chemotactic signal transduction during colonization and disease

我们建议的研究重点是确定TLPA和TlpB化学受体的作用机制 在引起溃疡的幽门螺杆菌的发病机制中起着基础性作用。这些受体 调节幽门螺杆菌引起的炎症。然而，我们对这一问题的理解存在着根本性的差距 TLPA和TlpB信号，这些受体如何感知它们的配体，它们如何执行信号转导，以及 它们是如何促进发病的。这种差距的持续存在阻碍了我们对 幽门螺杆菌的致病机制，从长远来看，阻止这些过程使 治疗幽门螺杆菌相关疾病的新药。全世界和美国有数百万人感染了H。 幽门螺杆菌，并患有与之相关的疾病--溃疡和胃癌。胃癌是第二大诱因 全球癌症死亡人数最多的国家。幽门螺杆菌的存在是基于最近的研究表明幽门螺杆菌的发病率 在发达国家稳定下来。此外，目前治疗幽门螺杆菌感染的方法都失败了，无法接受- 例如，美国最近的估计发现，20%-25%的感染者是 不能通过目前的治疗方法治愈。迫切需要新的药物靶点。具体目标 对TLPA和TlpB的信号转导及其在胃病中的作用作一综述。我们的中央- 假说是TLPA和TlpB转导来自特定配体的信息以影响细菌与宿主的相互作用， 致炎基因的表达，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的特定新配体的初步数据，开发关键试剂 为了分析TLPA和TlpB的信号转导途径，明确TLPA和TlpB在炎症中的作用，并研究TLPA和TlpB在炎症反应中的作用。 开发分析胃环境中幽门螺杆菌的新方法。在目标1中，我们确定了 TLPA和TlpB的配体结合和信号转导，使用纯化蛋白的体外结合试验 趋化信号转导实验和完整幽门螺杆菌趋化实验。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，我们将探索TlpA和TlpB突变体是否有 宿主细胞的异常相互作用和分布。最后，我们研究了宿主参数的假设 应用代谢组学分析营养物质在胃和胃中分布的感染病程变化 最先进的有机培养系统。这项拟议的研究具有创新性，因为它将创造新的 了解趋化作用在细菌致病过程中的作用及其应用现状 接近了。这项拟议的研究意义重大，因为它涉及趋化性，这是一种基本特性 对许多病原体很重要，并特别关注一种导致猖獗疾病的细菌，但对于 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 洞察力将使创造治疗幽门螺杆菌相关疾病的新药成为可能。

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.