Mechanisms of gastric mucosal response to H. pylori infection at acidic pH

酸性pH下胃粘膜对幽门螺杆菌感染的反应机制

• 批准号: 8617107
• 负责人: Elizabeth A. Marcus
• 金额: $ 15.24万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8617107
• 关键词: Acclimatization; Acidity; Acids; Acute; Advisory Committees; Amino Acids; Amoxicillin; Animal Model; Antibiotic Resistance; Antibiotic Therapy; Antibiotics; Atrophic Gastritis; Bacteria; Bacterial Physiology; Basic Science; Biological Models; California; Cell Culture Techniques; Cells; Childhood; Clarithromycin; Clinical; Coculture Techniques; Commit; Complex; Confocal Microscopy; Data; Development; Disease; Duodenal Ulcer; Environment; Epithelial; Epithelial Cell Junction; Epithelial Physiology; Epithelium; Eukaryotic Cell; Fellowship; Fostering; Gastric mucosa; Gastric ulcer; Gastritis; Gastroenterology; Genes; Gerbils; Goals; Helicobacter Infections; Helicobacter pylori; Human; IL8 gene; Immune response; Immune system; Immunology; In Vitro; Infection; Infection prevention; Inflammation; Inflammatory Infiltrate; Inflammatory Response; Injury; Integration Host Factors; Intercellular Junctions; Knowledge; Lead; Life; Los Angeles; Malignant Neoplasms; Mass Spectrum Analysis; Mediator of activation protein; Mentors; Metronidazole; Microscopy; Modeling; Monitor; Mucositis; Outcome; Pathologic; Pathology; Pathway interactions; Patients; Pediatric Hospitals; Pediatrics; Peptic Ulcer; Permeability; Pharmaceutical Preparations; Physiological; Physiology; Population; Postdoctoral Fellow; Prevention; Prevention strategy; Principal Investigator; Process; Production; Program Development; Proteins; Proton Pump Inhibitors; Recording of previous events; Regimen; Research; Research Personnel; Residencies; Resistance; Risk; Role; Signaling Molecule; Stable Isotope Labeling; Stomach; Stomach Carcinoma; Stomach Diseases; System; Technology; Testing; Time; Training; Training Programs; Treatment Efficacy; Treatment Protocols; Ulcer; Universities; Virulence Factors; Work; advanced disease; base; career; career development; compliance behavior; cytokine; falls; graduate student; immune activation; improved; in vitro Model; in vivo; in vivo Model; infectious disease treatment; injured; instructor; malignant stomach neoplasm; medical schools; mucosa-associated lymphoid tissue lymphoma; novel; pathogen; pediatric department; professor; programs; public health relevance; research and development; research study; response; skills; success; treatment duration

Project Summary/Abstract This proposal describes a four-year basic science training program for the development of a career in academic Pediatric Gastroenterology. The prinicpal investigator, Dr. Elizabeth A. Marcus, a Clinical Instructor in Pediatric Gastroenterology at the University of California, Los Angeles with a projected title of Assistant Professor as of 7/1/13, is board-certified in General Pediatrics and Pediatric Gastroenterology. She completed Pediatrics residency at Children's Hospital Los Angeles. She participated in basic science research, studying the acid acclimation mechanisms and bacterial physiology of the gastric pathogen Helicobacter pylori throughout medical school, residency, and fellowship. The current proposal incorporates a newly developed and divergent research focus, studying the effect of the bacteria and acidic pH on the gastric mucosa. The program outlined in this proposal will provide the applicant with an excellent research environment and protected time to attain the skills needed to achieve her goal of becoming an independent investigator. The mentor, Dr. George Sachs, is a recognized expert in gastric physiology, acid secretion, and bacterial factors associated with H. pylori acid acclimation. Dr. Sachs has a strong history of mentoring graduate students and postdoctoral fellows who have progressed to become independent investigators. Co-mentor Dr. David Scott will contribute expertise on H. pylori, microscopy, animal models, and eukaryotic cell systems. Co-mentor Dr. Charalabos Pothoulakis will provide expertise on inflammation and mucosal immunology. An advisory committee will monitor career development and provide additional training in immunology, mass spectrometry and epithelial physiology. The Department of Pediatrics has already committed 75% protected research time to the applicant. UCLA provides a rich research and academic environment that will foster the development of research independence. The proposed research focuses on how H. pylori, in coordination with gastric acidity, is able to injure the gastric mucosa and trigger development of advanced disease. H. pylori infection is highly prevalent worldwide and at a minimum causes gastric inflammation. Some of those infected progress to develop gastric or duodenal ulcer disease, gastric atrophy, and cancer. Treatment is becoming more difficult with emerging antibiotic resistance and problems with patient compliance with a complex treatment regimen. It is not definitively known how the bacteria are able to evade the immune system, leading to lifelong infection, or what factors contribute to development of advanced disease, although multiple bacterial and host factors have been studied. This proposal will use in vitro and in vivo model systems with physiologic similarities to the host environment to determine epithelial changes and alterations in immune response. Quantitative mass spectrometry using SILAC (Stable Isotope Labeling by Amino acids in Cell culture) technology will be used to study protein changes in the cell junction in response first to acidity, then to H. pylori infection. Candidiate proteins or pathways will be inhibited to confirm involvement. Confocal microscopy will be used to further study the cell junctions in co-culture with acidic pH. Cell layer resistance and permeability changes will be characterized. Mediators involved with the Th1 and Th17 immune responses will be studied in the context of H. pylori infection and acidic pH. H. pylori genes with increased expression in acid and in a gerbil model will be studied as potential modulators of immune response. Potent acid inhibition with a novel acid blocker in infected gerbils will be employed to determine the effect on bacterial load, inflammatory infiltrate, and cytokine production. It is anticipated that this work will add to the understanding of the mechanisms of gastric injury and will lead to development of novel treatment targets for both the infection and its short and long term consequences to the host.

项目总结/摘要 该提案描述了一个为期四年的基础科学培训计划， 儿科胃肠病学首席研究员伊丽莎白·A.马库斯，临床导师 在加州大学洛杉矶的儿科胃肠病学，预计头衔为助理 截至2013年7月1日，教授获得了普通儿科和儿科胃肠病学的委员会认证。她完成 洛杉矶儿童医院儿科住院医师。她参与了基础科学研究， 幽门螺杆菌的酸适应机制和细菌生理学 在医学院实习和奖学金期间目前的建议包括一个新开发的 研究重点不同，主要研究细菌和酸性pH对胃粘膜的影响。的 本建议书中概述的计划将为申请人提供一个良好的研究环境， 保护时间，以获得所需的技能，实现她的目标，成为一名独立的调查员。的 导师乔治萨克斯博士是公认的胃生理学、胃酸分泌和细菌因素方面的专家 与H. pylori酸驯化。萨克斯博士在指导研究生方面有着悠久的历史， 已经发展成为独立研究者的博士后研究员。共同导师大卫斯科特博士 将在H. pylori、显微镜、动物模型和真核细胞系统。共同导师Dr. Charalabos Pothoulakis将提供炎症和粘膜免疫学方面的专业知识。一个咨询 委员会将监测职业发展，并提供免疫学、质谱学和生物医学方面的额外培训。 和上皮生理学。儿科系已经承诺75%的受保护研究时间， 申请人。加州大学洛杉矶分校提供了丰富的研究和学术环境，将促进发展， 研究独立性。 本文主要研究H.幽门螺杆菌，在协调与胃酸，是能够损害 胃粘膜和触发发展的先进的疾病。H.幽门螺杆菌感染非常普遍 在世界范围内，至少会引起胃炎。有些感染者会发展成胃溃疡 或十二指肠溃疡疾病、胃萎缩和癌症。治疗变得越来越困难， 抗生素耐药性和患者对复杂治疗方案的依从性问题。不 明确知道细菌如何能够逃避免疫系统，导致终身感染，或者什么 虽然多种细菌和宿主因素已经被证实是导致晚期疾病发展的原因， 研究了该提案将使用与宿主生理相似的体外和体内模型系统 环境，以确定上皮细胞的变化和免疫反应的改变。定量质量 使用SILAC（细胞培养物中氨基酸的稳定同位素标记）技术的光谱分析将用于 研究细胞连接处蛋白质的变化，首先是对酸性的反应，然后是对H的反应。幽门感染无菌的 蛋白质或途径将被抑制以确认参与。共聚焦显微镜将用于进一步研究 细胞层电阻和渗透性的变化将是 表征了将在H. pylori感染和酸性pH。在酸和沙鼠模型中表达增加的幽门螺杆菌基因将被 作为免疫反应的潜在调节剂。一种新的酸阻断剂在感染中的强效酸抑制作用 将使用沙鼠来确定对细菌负荷、炎性浸润和细胞因子的影响 生产预计这项工作将增加对胃损伤机制的理解， 将导致开发新的治疗目标，无论是感染和其短期和长期 对宿主的影响。