NEW ANIMAL MODEL FOR EHEC PATHOGENESIS AND PREVENTION

用于 EHEC 发病和预防的新动物模型

• 批准号: 6637168
• 负责人: JOAN R BUTTERTON
• 金额: $ 31.76万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-30 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6637168
• 关键词: Enterobacteriaceae; Enterobacteriaceae disease; Escherichia coli 0157:H7; Escherichia coli infections; Vibrio cholerae; attenuated microorganism; bacillary dysentery; bacterial antigens; bacterial vaccines; disease /disorder model; exotoxins; genetic transduction; hemolytic anemia; hemorrhagic disorders; laboratory mouse; live vaccine; lysogeny; mucosal immunity; nonhuman therapy evaluation; plasmids; renal failure; shiga toxin; transfection /expression vector; vaccine development; vector vaccine

DESCRIPTION (adapted from the application) Investigation of the gastrointestinal disease and renal injury caused by enterohemorrhagic Escherichia coli (EHEC) and the development and testing of interventions to prevent disease following infection have been hampered by the lack of a convenient animal model that effectively reproduces the typical human colonic disease that progresses to HUS. The Principal Investigator proposes to develop the use of a new mouse model of EHEC infection with the long term goal of increasing the ability to study disease pathogenesis and prevention. The new animal model will be compared with prior models in the evaluation of vaccine strategies against EHEC. This will be accomplished through the following two Specific Aims: 1. Evaluation of the use of Citrobacter rodentium expressing Stx in a mouse model of Shiga toxin-producing E. Coli (STEC) infection. C. rodentium, a naturally occurring pathogen of laboratory mice which causes transmissible murine colonic hyperplasia, binds to the mouse enterocyte by a specific attachment and effacement lesion similar to that of EHEC. Strategies have been developed to lysogenize C. rodentium with antibiotic-marked Stx1- and Stx2-expressing bacteriophages as well as to express toxin components from plasmid vectors. Toxin production, phage induction, and lysogen stability will be evaluated in vitro. Mice will be challenged with toxin-producing C. rodentium and evaluated for clinical and pathologic signs of disease. This model has the potential of reproducing both the gastrointestinal and renal injury seen in EHEC infection, allows the use of adult animals and the development of normal immune responses, utilizes the power of mouse genetics to investigate genetic factors in determining gastrointestinal (GI) and systemic disease expression, and provides a significant increase in the ease of identifying and testing new interventions compared to many other animal models. 2. Expression of nontoxic Stx1 and Stx2 antigens using a balanced lethal plasmid system in Vibrio cholerae vaccine strains. Vibrio cholerae will be used as a live oral attenuated vaccine vector to deliver immunogenic antigens of EHEC to stimulate a common mucosal immune response. A balanced lethal plasmid system will be used to provide stable expression of the heterologous antigens from the vaccine strains. The germfree mouse model of V. cholerae colonization will be used to examine mucosal and systemic immune responses to the toxin components expressed by the vector strains. The new mouse challenge model will be compared to prior mouse models in evaluating protection from disease in response to immunization with V. cholerae strains expressing the EHEC antigens.

描述（根据应用程序改编） 研究胃肠道疾病和肾损伤 Enterohehemorrhagic大肠杆菌（EHEC）和开发和测试 预防感染后预防疾病的干预措施受到了 缺乏方便的动物模型，可以有效地再现典型的人类 结肠疾病发展为HUS。首席调查员向 开发使用长期目标的EHEC感染的新鼠标模型 增加研究疾病发病机理和预防的能力。新的 在评估疫苗时，将将动物模型与先前模型进行比较 针对EHEC的策略。这将通过以下两个完成 具体目的：1。表达柠檬酸杆菌的使用评估 在产生的志贺毒素大肠杆菌（STEC）感染的小鼠模型中。 C 啮齿动物，一种自然存在的实验室小鼠病原体，导致 可传播的鼠结肠增生，通过A结合小鼠肠球菌 特定的附着和递增病变类似于EHEC。策略 已经开发了用抗生素标记的STX1-和 表达STX2的噬菌体以及表达毒素成分 质粒向量。毒素的产生，噬菌体诱导和溶菌原稳定性将 在体外评估。小鼠将通过产生毒素的挑战。 啮齿动物并评估了疾病的临床和病理迹象。这 模型具有再现胃肠道和肾脏的潜力 EHEC感染中看到的伤害，允许使用成年动物和 发展正常免疫反应，利用小鼠遗传学的力量 研究确定胃肠道（GI）和全身性的遗传因素 疾病表达，并具有显着的易度提高 与许多其他动物模型相比，识别和测试新干预措施。 2。使用平衡致死的无毒STX1和STX2抗原的表达 Vibrio Cholerae疫苗菌株中的质粒系统。将使用Vibrio Cholerae 作为活口水疫苗载体，以提供免疫原性抗原 EHEC刺激常见的粘膜免疫反应。平衡致死质粒 系统将用于提供异源抗原的稳定表达 从疫苗菌株中。霍乱弧菌定植的无毛小鼠模型 将用于检查对毒素的粘膜和全身免疫反应 矢量菌株表达的组件。新的鼠标挑战模型将 在评估保护免受疾病的保护中的先前小鼠模型 用表达EHEC抗原的霍乱菌菌株对免疫的反应。