Shiga toxin activity in human intestinal organoids

人类肠道类器官中志贺毒素的活性

• 批准号: 9035240
• 负责人: Alison A. Weiss
• 金额: $ 23.72万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-19 至 2018-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9035240
• 关键词: Actins; Acute Kidney Failure; Adherence; Adult; Antibiotic Therapy; Antibiotics; Bacterial Attachment Site; Bacterial Infections; Bacteriophages; Biological Models; Blood Circulation; Blood Platelets; Blood flow; Cessation of life; Characteristics; Child; Citrobacter rodentium; Complication; Cytoplasm; Disease; Disease Outbreaks; Disease Outcome; Disease model; Enterocytes; Epithelial; Epithelial Cells; Epithelium; Erythrocytes; Escherichia coli; Escherichia coli EHEC; Escherichia coli O157:H7; Experimental Models; Genes; German population; Glycolipids; Hemolytic Anemia; Hemolytic-Uremic Syndrome; Hemorrhagic colitis; Hospitalization; Human; Immune response; Individual; Infection; Injection of therapeutic agent; Intestines; Intraperitoneal Injections; Kidney; Kidney Diseases; Lesion; Life; Mammalian Cell; Mediating; Medical Economics; Membrane Microdomains; Microbial Biofilms; Modeling; Mus; Organoids; Papio; Pathogenicity Island; Patients; Pattern; Phenotype; Primates; Process; Production; Protein Biosynthesis; Proteins; Resistance; Ribosomes; Shiga Toxin; Staining method; Stains; Stem cells; Structure; Symptoms; System; Thrombus; Time; Tissues; Toxin; Variant; Virulence Factors; cell type; cellular microvillus; enteric pathogen; enteroaggregative Escherichia coli; enteropathogenic Escherichia coli; foodborne illness; globotriaosylceramide; human disease; insight; intestinal epithelium; intravenous injection; mouse model; novel; pathogen; pathogenic Escherichia coli; pathogenic bacteria; public health relevance; three dimensional structure

 DESCRIPTION (provided by applicant): Shiga toxin (Stx) is the primary virulence factor of Stx producing Eschrichia coli (STEC), a leading cause of food-borne illnesses. Annually, STEC, including E. coli O157:H7, cause over 100,000 cases of infectious watery and bloody diarrhea in the U.S. About 10% of the infected progress to the life-threatening kidney disorder, hemolytic uremic syndrome (HUS). The symptoms of HUS can be replicated in primates treated with purified Stx. In HUS, platelet thrombus formation in the microvasculature compromises blood flow to the kidney, and hemolytic anemia develops when red blood cells are mechanically sheared as they squeeze through the occluded vessels. For reasons that are not clear, young children are more likely to develop HUS than adults, and it is the most common cause of acute kidney failure in children. Currently, there is no treatment for the systemic manifestations of HUS. In addition, antibiotics induce STEC to produce higher quantities of Stx, and antibiotic treatment is correlated with more severe disease outcome. A major barrier in the field is the lack of tractable mammalian models that replicate human disease, and as a consequence little is known about the actions of Stx protein toxin or the STEC pathogens on healthy, differentiated human intestinal tissues. We have developed an exciting new experimental model to study the effects of Stx and STEC on the human intestinal tract. Stem cell 'induced human intestinal organoids' (iHIOs) faithfully represent differentiated human intestinal tissue. Our preliminary studies show human intestinal organoids are sensitive to Stx injected into the lumen. Furthermore, while harmless E. coli can replicate in the lumen without causing damage, pathogenic E. coli O157:H7 destroy the intestinal epithelial barrier. This proposal will use human intestinal organoids as a novel model system to study the pathogenic processes associated with Stx and STEC. We will compare infection by harmless E. coli and pathogenic O157:H7 strains, with or without the ability to produce Stx. Aim 1 will focus on the host parameters of disease and Aim 2 will focus on the relative contribution of the bacterial virulence factors: Aim 1. What is the host response to bacterial infection and Stx expression? Aim 2. What is the relative contribution of Stx versus the pathogenic O157:H7 phenotype in mediating intestinal damage?

 描述（由申请人提供）：志贺毒素（Stx）是产 Stx 大肠杆菌（STEC）的主要毒力因子，而 STEC 是食源性疾病的主要原因。每年，包括大肠杆菌 O157:H7 在内的 STEC 在美国引起超过 100,000 例传染性水样腹泻和血性腹泻。其中约 10% 的感染者会发展为危及生命的肾脏疾病，即溶血性尿毒症综合征 (HUS)。 HUS 的症状可以在用纯化的 Stx 治疗的灵长类动物身上复制。在 HUS 中，微脉管系统中的血小板血栓形成会损害流向肾脏的血液，当红细胞挤压通过闭塞血管时受到机械剪切时，就会发生溶血性贫血。由于尚不清楚的原因，幼儿比成人更容易患 HUS，并且它是儿童急性肾衰竭的最常见原因。目前，尚无针对 HUS 全身表现的治疗方法。此外，抗生素会诱导 STEC 产生更多的 Stx，而抗生素治疗与更严重的疾病结果相关。 该领域的一个主要障碍是缺乏可复制人类疾病的易处理的哺乳动物模型，因此人们对 Stx 蛋白毒素或 STEC 病原体对健康、分化的人类肠道组织的作用知之甚少。我们开发了一个令人兴奋的新实验模型来研究 Stx 和 STEC 对人体肠道的影响。干细胞“诱导的人类肠道类器官”（iHIO）忠实地代表了分化的人类肠道组织。我们的初步研究表明，人类肠道类器官对注入管腔的 Stx 敏感。此外，虽然无害的大肠杆菌可以在肠腔中复制而不造成损害，但致病性大肠杆菌 O157:H7 会破坏肠上皮屏障。 该提案将使用人类肠道类器官作为新的模型系统来研究与 Stx 和 STEC 相关的致病过程。我们将比较无害的大肠杆菌和致病性 O157:H7 菌株的感染，无论是否具有产生 Stx 的能力。目标 1 将重点关注疾病的宿主参数，目标 2 将重点关注细菌毒力因子的相对贡献： 目标 1. 宿主对细菌感染和 Stx 表达的反应是什么？目标 2. Stx 与致病性 O157:H7 表型在介导肠道损伤方面的相对贡献是什么？