Dynamics of Campylobacter jejuni and host responses in the porcine intestinal-loop infection model

猪肠袢感染模型中空肠弯曲菌的动态和宿主反应

• 批准号: 9243740
• 负责人: Michael E Konkel
• 金额: $ 23.42万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-12-15 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9243740
• 关键词: Abdominal Cramps; Acute; Animals; Bacteria; Bile Acids; Biopsy; Blood; Campylobacter; Campylobacter infection; Campylobacter jejuni; Cells; Centers for Disease Control and Prevention (U.S.); Clinical; Complication; Data; Defecation; Diarrhea; Disease; Dysentery; Epithelial Cells; Experimental Designs; Exudate; Family suidae; Feces; Fever; Funding; Gene Expression; Genes; Genetic Variation; Genome; Genomics; Growth; Guillain-Barré Syndrome; Harvest; Hemorrhagic colitis; Human; Immune response; In Vitro; Individual; Infection; Inflammatory; Intestines; Invaded; Laboratories; Lesion; Leukocytes; Liquid substance; Mediating; Metabolism; Modeling; Nutrient; Outcome; Paralysed; Permeability; Phenotype; Physiological; Poliomyelitis; Proteins; Publishing; RNA; Reporting; Research Personnel; Research Project Grants; Severities; Symptoms; Testing; Tissue-Specific Gene Expression; Tissues; Variant; Villus; Virulence; comparative; cytokine; deoxycholate; differential expression; disorder prevention; experience; gut microbiota; in vivo; insight; metabolomics; mucoid; novel strategies; pathogen; rectal; response; transcriptome; transcriptome sequencing; transcriptomics

Project Summary Infection with Campylobacter jejuni is responsible for millions of cases of diarrhea per year and is a common precursor to Guillain-Barré syndrome, the leading cause of flaccid paralysis. Some individuals infected with C. jejuni experience watery diarrhea consisting of more than 10 stools per day whereas others suffer from inflammatory diarrhea with small-volume mucoid stool containing blood. It is currently uncertain whether the infectious C. jejuni strain, an individual's immune response, or both contribute to the variation in symptoms, severity, and duration of C. jejuni-mediated disease. Our central hypothesis is that the variation in clinical presentation associated with C. jejuni strains is, in part, due to differences in C. jejuni gene expression between strains. Invasive strains of C. jejuni cause bloody diarrhea whereas less-invasive strains cause diarrhea without blood (fewer of these bacteria invade and multiply in intestinal cells). We further hypothesize that infection with invasive strains of C. jejuni will result in greater host pro-inflammatory cytokines and Th17 cytokines (influence gut permeability) than infection with less-invasive strains. Finally, we hypothesize that C. jejuni infection (regardless of phenotypes) will result in a shift in the host-gut metabolism that, at least initially, favors its growth in the intestine. The novelty of this proposal is the use of the pig ligated-intestinal loop model to establish discrete replicative niches for four distinct (sequenced) C. jejuni strains in the intestinal lumen. Two of the C. jejuni strains to be tested in our model cause bloody diarrhea in pigs whereas two strains result in diarrhea without blood. Our preliminary studies have revealed that: 1) Significant genetic diversity exists amongst these four C. jejuni strains; and 2) C. jejuni synthesize a number of proteins either exclusively or preferentially when grown under host-like conditions (in the presence of epithelial cells or with a physiologically relevant concentration of the bile acid deoxycholate) as compared to nutrient broth, as judged by microarray (published) and RNA-Seq analysis (unpublished). In vivo studies are needed to determine the relationship between C. jejuni virulence gene expression and clinical disease presentation and to provide information regarding the complexity of the host response to different strains. The Specific Aims of this proposal are to: 1) Identify unique and/or differentially expressed genes using RNA extracted from C. jejuni cultured in the laboratory versus from C. jejuni collected from pig ligated-intestinal loops by transcriptomics. 2) Characterize the host response to infection with C. jejuni strains that cause bloody versus watery diarrhea. 3) Perform comparative metabolomics of luminal contents from uninfected and C. jejuni-infected loops.

项目摘要 空肠弯曲杆菌感染是每年数百万例腹泻的原因， 格林-巴利综合征的前兆，这是弛缓性麻痹的主要原因。一些人感染了C。 空肠经历水样腹泻，包括每天超过10次大便，而其他空肠经历水样腹泻， 炎性腹泻伴少量粘液样便，含血。目前尚不确定， 传染性C.空肠菌株，个体的免疫反应，或两者都有助于症状的变化， 严重程度和持续时间。空肠介导的疾病。 我们的中心假设是，临床表现的变化与C。空肠菌株，部分地， 由于C. jejuni基因在菌株间的表达。入侵菌株C.空肠出血 腹泻，而侵入性较低的菌株引起腹泻而不流血（这些细菌侵入较少， 在肠细胞中繁殖）。我们进一步假设，感染侵袭性的C。空肠会导致 更大的宿主促炎细胞因子和Th 17细胞因子（影响肠道通透性）比感染 侵袭性较小的菌株。最后，我们假设C。空肠感染（无论表型如何）将导致 宿主肠道代谢的转变，至少在最初，有利于其在肠道中的生长。 该建议的新奇在于使用猪结扎肠袢模型来建立离散的复制模型。 四个不同的小生境（测序）C。肠腔中的空肠拉伤。两个C。空肠菌株 在我们的模型中测试的菌株导致猪的血性腹泻，而两种菌株导致无血腹泻。我们 初步研究表明：1）这4个种间存在显著的遗传多样性;空肠 菌株; 2）C.空肠在生长条件下， 宿主样条件（存在上皮细胞或具有生理相关浓度的胆汁 酸脱氧胆酸盐）与营养肉汤相比，如通过微阵列（已发表）和RNA-Seq分析判断的 （未发表）。需要体内研究来确定C.空肠毒力基因 表达和临床疾病表现，并提供关于宿主复杂性的信息， 对不同菌株的反应。 该提案的具体目标是： 1)利用从C.空肠培养 实验室与C.通过转录组学从猪结扎的肠袢收集空肠。 2)描述宿主对C.导致血性腹泻和水样腹泻的空肠菌株。 3)对未感染和C.空肠感染的肠袢