MECHANISMS FOR COMMENSAL MICROBIAL INTERACTIONS WITH THE INTESTINAL EPITHELIAL BARRIER

共生微生物与肠上皮屏障相互作用的机制

• 批准号: 9491797
• 负责人: Christina Kim Ahn Hickey
• 金额: $ 15.82万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-08 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9491797
• 关键词: Affect; Animal Genetics; Animal Model; Anticholesteremic Agents; Antigens; Award; Bacteroides thetaiotaomicron; Biological Assay; Biological Models; CRISPR/Cas technology; Cancer cell line; Caveolins; Cell Culture System; Cell Line; Cells; Cellular biology; Chemistry; Childhood; Colitis; Collaborations; Committee Members; Communities; Data; Defect; Defense Mechanisms; Development; Disease; Epithelial; Epithelial Cells; Epithelium; Fellowship; Funding; Future; Gastroenterology; Gene Targeting; Genes; Genetic; Genomics; Goals; Histologic; Hour; Human; Image; Immune; Immune response; Immunology; In Vitro; Incubated; Inflammatory Bowel Diseases; Intestines; K-Series Research Career Programs; Knowledge; Laboratories; Location; Martens; Mediating; Medical; Membrane; Membrane Microdomains; Mentors; Mesenchyme; Methods; Microbiology; Modification; Mucous body substance; Organism; Paper; Pathogenesis; Pathology; Pathway interactions; Pediatric Hospitals; Pharmacology; Physicians; Postdoctoral Fellow; Primary Cell Cultures; Process; Publishing; Recording of previous events; Research; Research Personnel; Residencies; Resources; Role; Sampling; Scientist; Side; Signal Pathway; Signal Transduction; Solid; Stem cells; System; Testing; Tight Junctions; Time; Training; Translating; Transmission Electron Microscopy; United States National Institutes of Health; Universities; Vesicle; Washington; Work; Writing; base; career; commensal bacteria; commensal microbes; genetic manipulation; graduate student; host-microbe interactions; human disease; improved; in vivo; interest; intestinal epithelium; mRNA Expression; medical schools; microbial host; microorganism interaction; monolayer; mouse model; novel; particle; pathogen; pediatric department; protein expression; skills; targeted treatment; tool; uptake

PROJECT SUMMARY The goal of this proposal is to describe a 4 year plan for the PI, Christina Hickey, MD, to prepare for her independence as a physician scientist studying key epithelial cell signaling pathways triggered by commensal microbes that affect the development of inflammatory bowel disease. The PI graduated with distinction from Stanford University with a degree in Chemistry. She then obtained her medical degree from Washington University School of Medicine and completed her residency and pediatric gastroenterology fellowship at St. Louis Children's Hospital. During her fellowship, she published a first author paper with her current mentor, Dr. Thaddeus Stappenbeck, with the key finding that Bacteroides thetaiotaomicron (B. theta) outer membrane vesicles (OMVs) access immune cells in the intestine in an inflammatory bowel disease (IBD) mouse model. These findings serve as the basis for the aims in this proposal. Washington University School of Medicine and the Department of Pediatrics are exemplary locations for Dr. Hickey to start her research career with their collective longstanding history of NIH funded researchers and breadth and depth of resources from state of the art imaging centers to histological cores. In addition, there is frequent crosstalk and collaboration between departments, as Dr. Hickey's impressive mentoring committee and set of collaborators suggest, combining the expertise from the departments of microbiology (Drs. Martens, Beatty, and Tarr), immunology (Drs. Virgin and Allen), pathology (Dr. Stappenbeck), cell biology (Drs. Hou and Stahl) and gastroenterology (Dr. Tarr). The PI's mentor Dr. Stappenbeck is a leader in the field of intestinal host-microbial interactions; he is the ideal mentor for Dr. Hickey because of his keen ability to probe significant questions about pathogenesis, his solid track record in training young scientists, and his skill in writing, presentations, and troubleshooting projects. Furthermore, the Stappenbeck laboratory in which she is training is a hub of creative intellectual energy, composed of multiple post-doctoral fellows, graduate students, and technicians working on a broad range of projects. Dr. Hickey will also have multiple opportunities to present her work at Washington University and in the broader scientific community. The PI plans to take graduate level classes to enhance her knowledge in cellular biology and genomics. Finally, she will develop key skills in the labs of her collaborators and mentoring committee members. At the end of the 4 year award period, the PI will have accumulated the knowledge and skills she requires to become a successful physician scientist with an expertise in epithelial- commensal interactions. The PI's immediate goal is to fulfill the aims in this proposal. While it is clear that commensal microbial interactions with the intestinal epithelium are important for the development of pathogenesis, these interactions are poorly defined. In particular, she has recently shown that B. theta, a commensal organism, releases outer membrane vesicles that access the host immune cells on the basolateral side of the epithelium, indicating they have mechanisms to cross the epithelial barrier. Previous studies examining this host-microbial interface have utilized cancer cell lines and pathogens, which are not ideal tools to delineate this process. In this application, the PI proposes to utilize primary cell lines derived from genetic mouse models and OMVs isolated from the commensal microbe B. theta to probe the following: 1) the mechanism of epithelial internalization of B. theta OMVs, 2) the cell signaling pathways triggered by this internalization, and 3) the process by which OMVs pass through the epithelial layer. Based on her preliminary data, she hypothesizes that epithelial cells internalize B. theta OMVs via caveolin mediated lipid rafts, and the OMVs trigger epithelial signaling pathways to upregulate the internalization of additional OMVs, presumably to process them as a defense mechanism (Aim I). However, her preliminary findings also suggest that OMVs still traverse the epithelial layer, likely through defective tight junctions (Aim II). With the mechanisms uncovered in these aims, she will be ideally poised to fulfill her long- term goal of starting her own independent laboratory. Her lab's initial focus will be to determine the complete pathways of these mechanisms. Ultimately, she aims to translate her findings to human samples, which is critical for the development of more targeted therapies for inflammatory bowel disease.

项目摘要 该提议的目的是描述PI的4年计划，马里兰州克里斯蒂娜·希基（Christina Hickey） 独立作为医师的科学家，研究了由Consensal触发的关键上皮细胞信号传导途径 影响炎症性肠病发展的微生物。 PI从 斯坦福大学获得化学学位。然后，她从华盛顿获得了医学学位 大学医学院，并在圣 路易儿童医院。在奖学金期间，她与现任导师博士发表了第一篇作者论文。 thaddeus stappenbeck，其关键发现是菌落thetaiotaomicron（B。theta）外膜 囊泡（OMV）在炎症性肠病（IBD）小鼠模型中访问肠中的免疫细胞。 这些发现是该提案目标的基础。 华盛顿大学医学院和儿科系是模范地点 Hickey博士以NIH资助的研究人员的共同历史开始她的研究生涯 从艺术成像中心到组织学核心的广度和深度。此外， Hickey博士令人印象深刻的指导，部门之间经常进行串扰和协作 委员会和一组合作者建议，结合了微生物学系的专业知识 （Martens，Beatty和Tarr博士），免疫学（Virgin和Allen博士），病理学（Stappenbeck博士），细胞生物学 （Hou和Stahl博士）和胃肠病学（Tarr博士）。 PI的导师Stappenbeck博士是肠道宿主 - 微生物相互作用领域的领导者。他是 Hickey博士的理想导师是因为他敏锐地探究有关发病机理的重大问题的能力， 他在培训年轻科学家的稳固记录以及他在写作，演示和故障排除方面的技巧 项目。此外，她正在培训的Stappenbeck实验室是创意知识的枢纽 能源，由多个博士后研究员，研究生和技术人员组成 项目范围。希基博士还将有多个机会在华盛顿大学介绍她的作品 以及更广泛的科学界。 PI计划参加研究生课程以增强她的知识 在细胞生物学和基因组学中。最后，她将在合作者的实验室中发展关键技能 指导委员会成员。在4年颁奖期结束时，PI将累积 她需要成为一名成功的医师科学家所需的知识和技能，并具有上皮方面的专业知识 共同互动。 PI的直接目标是实现该提案中的目标。虽然很明显，共生微生物 与肠上皮的相互作用对于发病机理的发展很重要，这些相互作用 定义很差。特别是，她最近表明，塞塔（B. theta 在上皮基底外侧的宿主免疫细胞上进入宿主免疫细胞的膜囊泡，表明它们 具有越过上皮屏障的机制。以前检查此宿主微生物界面的研究具有 利用癌细胞系和病原体，这不是描述此过程的理想工具。在此应用程序中 PI提议利用从遗传小鼠模型中得出的主要细胞系，而OMV从 共生微生物B. theta探测以下内容：1）theta上皮内在化的机理 OMV，2）该内部化触发的单元信号通路，以及3）OMV通过的过程 通过上皮层。根据她的初步数据，她假设上皮细胞内部化B。 通过小窝蛋白介导的脂质筏的theta OMV，OMV触发上皮信号传导途径上调 其他OMV的内部化，大概是将它们作为防御机制进行处理（AIM I）。然而， 她的初步发现还表明，OMV仍然横穿上皮层，可能是通过有缺陷的紧密 连接（AIM II）。随着这些目标中发现的机制，她将被理想地实现她的长期 开始自己的独立实验室的任期目标。她的实验室最初的重点是确定完整 这些机制的途径。最终，她旨在将她的发现转化为人类样本，这是 对于开发更靶向炎症性肠病的靶向疗法至关重要。