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.

项目摘要/摘要 该提案描述了一项为期四年的基础科学培训计划，以发展职业 学术儿科胃肠病学。临床讲师伊丽莎白·A·马库斯（Elizabeth A. Marcus）博士 加利福尼亚大学洛杉矶分校的儿科胃肠病学博士学位 截至13年7月1日，教授在一般儿科和儿科胃肠病学中获得董事会认证。她完成了 洛杉矶儿童医院的儿科住院医师。她参加了基础科学研究 胃病原体幽门螺杆菌的酸适应机制和细菌生理 整个医学院，居住和团契。当前的提案结合了一个新开发的 研究重点是研究细菌和酸性pH对胃粘膜的影响。这 该提案中概述的计划将为申请人提供出色的研究环境和 保护时间以实现自己成为独立调查员的目标所需的技能。这 导师乔治·萨克斯（George Sachs）博士是胃生理，酸分泌和细菌因素的公认专家 与幽门螺杆菌的适应相关。萨克斯博士在指导研究生和 后来成为独立调查员的博士后研究员。同事戴维·斯科特博士 将在幽门螺杆菌，显微镜，动物模型和真核细胞系统上贡献专业知识。联合主管博士 Charalabos Pothoulakis将提供有关炎症和粘膜免疫学的专业知识。咨询 委员会将监视职业发展，并提供有关免疫学，质谱法的其他培训 和上皮生理学。儿科部已经承诺了75％的保护时间 申请人。 UCLA提供了丰富的研究和学术环境，以促进 研究独立性。 拟议的研究侧重于幽门螺杆菌如何与胃酸性协调能够损害 胃粘膜并触发晚期疾病的发展。幽门螺杆菌感染高度普遍 全球，最少会引起胃发炎。其中一些感染了发展胃的进展 或十二指肠溃疡，胃萎缩和癌症。随着新兴的待遇，治疗变得越来越困难 抗生素耐药性和患者遵守复杂治疗方案的问题。它不是 最终知道细菌如何能够逃避免疫系统，导致终生感染或什么 尽管多种细菌和宿主因素是 研究。该建议将使用与宿主具有生理相似性的体外和体内模型系统 确定上皮变化和免疫反应改变的环境。定量质量 使用SILAC（细胞培养中氨基酸稳定的同位素标记）的光谱法将用于 研究蛋白在酸度的响应中，然后对幽门螺杆菌感染的蛋白质变化。候选人 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 与酸性pH共培养的细胞连接。细胞层的抗性和渗透率的变化将是 特征。将研究与TH1和TH17免疫反应有关的介质。 幽门螺杆菌感染和酸性pH。幽门螺杆菌基因在酸和沙鼠模型中表达增加的基因将是 研究是免疫反应的潜在调节剂。在感染的新型酸阻滞剂中抑制有效的酸 将使用沙鼠来确定对细菌负荷，炎症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和 将导致感染及其短期和长期感染的新型治疗目标发展 主机的后果。