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: 9344597
• 负责人: Elizabeth A. Marcus
• 金额: $ 10.41万
• 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 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9344597
• 关键词: Acclimatization; Acidity; Acids; Acute; Advanced Development; 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; 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; Impairment; 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; 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; 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

DESCRIPTION (provided by applicant): This proposal describes a four-year basic science training program for the development of a career in academic Pediatric Gastroenterology. The principal investigator, Dr. Elizabeth A. Marcus, a Clinical Instructor in Pediatric Gastroenterolog 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. Candidate 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.

描述（由申请人提供）：该提案描述了一项为期四年的基础科学培训计划，用于发展学术儿科胃肠病学职业。首席研究员伊丽莎白·A·马库斯（Elizabeth A.她在洛杉矶儿童医院完成了儿科住院医师。她参与了基础科学研究，研究了整个医学院，居住和研究金的胃病原体幽门螺杆菌的酸性适应机制和细菌生理学。当前的提案结合了新开发和不同的研究重点，研究了细菌和酸性pH对胃粘膜的影响。该提案中概述的计划将为申请人提供出色的研究环境，并受到保护的时间，以实现她成为独立调查员的目标所需的技能。这位导师乔治·萨克斯（George Sachs）博士是胃生理，酸分泌和与幽门螺杆菌酸适应的细菌因子的公认专家。萨克斯博士拥有悠久的历史，指导研究生和博士后研究员，他们已经发展成为独立的调查员。戴维·斯科特（David Scott）博士将在幽门螺杆菌，显微镜，动物模型和真核细胞系统方面贡献专业知识。 Charalabos Pothoulakis博士将提供有关炎症和粘膜免疫学的专业知识。咨询委员会将监测职业发展，并为免疫学，质谱和上皮生理学提供其他培训。儿科部已经向申请人致力于75％的保护时间。 UCLA提供了丰富的研究和学术环境，可促进研究独立性的发展。 拟议的研究重点是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。幽门螺杆菌感染在全球范围内高度普遍，最少引起胃炎。其中一些感染的进展是发展出胃或十二指肠溃疡疾病，胃萎缩和癌症。由于新兴的抗生素耐药性以及患者遵守复杂治疗方案的问题，治疗变得越来越困难。尽管已经研究了多种细菌和宿主因素，但尚不清楚细菌如何能够逃避免疫系统，导致终生感染或有助于晚期疾病的发展。该建议将使用与宿主环境具有生理相似性的体外和体内模型系统，以确定上皮变化和免疫反应的改变。使用SILAC（氨基酸在细胞培养中稳定的同位素标记）的定量质谱法技术将首先用于研究细胞连接的蛋白质变化，首先是对酸度的响应，然后是幽门螺杆菌感染。候选蛋白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。将表征细胞层的电阻和渗透率变化。将在幽门螺杆菌感染和酸性pH的背景下研究与TH1和TH17免疫反应有关的介质。幽门螺杆菌基因 在酸和沙鼠模型中的表达增加将作为免疫反应的潜在调节剂研究。在感染的沙鼠中使用新型酸阻滞剂的有效酸抑制作用将用于确定对细菌负荷，炎性浸润和细胞因子产生的影响。预计这项工作将增加对胃损伤机制的理解，并会导致感染及其对宿主的短期和长期后果的新型治疗靶标。

项目成果

Endoscopy Following Pediatric Intestinal Transplant.

• DOI: 10.1097/mpg.0000000000000871
• 发表时间: 2015-12
• 期刊: Journal of pediatric gastroenterology and nutrition
• 影响因子: 2.9
• 作者: Yeh J;Ngo KD;Wozniak LJ;Vargas JH;Marcus EA;McDiarmid SV;Farmer DG;Venick RS
• 通讯作者: Venick RS

Successful term pregnancy in an intestine-pancreas transplant recipient with chronic graft dysfunction and parenteral nutrition dependence: a case report.

患有慢性移植物功能障碍和肠外营养依赖的肠胰腺移植受者成功足月妊娠：病例报告。

• DOI: 10.1016/j.transproceed.2015.01.009
• 发表时间: 2015
• 期刊: Transplantation proceedings
• 影响因子: 0.9
• 作者: Marcus,EA;Wozniak,LJ;Venick,RS;Ponthieux,SM;Cheng,EY;Farmer,DG
• 通讯作者: Farmer,DG