Lactobacilli surface antibody expression for in vivo protection against cholera

乳酸杆菌表面抗体表达可体内预防霍乱

• 批准号: 7772625
• 负责人: PAUL WENTWORTH
• 金额: $ 28.49万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7772625
• 关键词: Adenylate Cyclase; Affect; Affinity; Africa; Americas; Antibodies; Antihypertensive Agents; Area; Asia; Asians; Back; Bacteria; Bacteriophages; Binding; Biotechnology; Bioterrorism; Blood Pressure; Categories; Cells; Cessation of life; Cholera; Cholera Toxin; Cholera Toxin Protomer B; Consumption; Country; Disease; Disease Outbreaks; Drops; Electrolyte Balance; Enterotoxins; Epidemic; Exposure to; Feces; Gastroenteritis; General Population; Genes; Hour; Human; Immunity; Immunoglobulin Fragments; Immunotherapy; Individual; Infection; Lactobacillus; Latin America; Lethal Dose 50; Libraries; Liquid substance; Measures; Medical; Military Personnel; Mus; National Institute of Allergy and Infectious Disease; Oral; Patients; Peripheral Blood Lymphocyte; Persons; Phage Display; Plasmids; Public Health; Rehydrations; Screening procedure; Seafood; Sewage; Shellfish; Shock; Small Intestines; Source; Staging; Surface; Symptoms; System; Testing; Toxic effect; Transportation; Travel; United States; Vaccination; Vaccines; Vegetables; Vibrio cholerae; Yogurt; clinical application; combat; combinatorial; drinking water; emergency service responder; food consumption; foodborne outbreak; gastrointestinal epithelium; improved; in vivo; mouse model; novel strategies; pathogen; prevent; prophylactic; protective effect; public health relevance; scaffold; sewage treatment; tool; vector; water treatment; waterborne

DESCRIPTION (provided by applicant): Cholera, sometimes known as Asian or epidemic cholera, is an infectious gastroenteritis caused by enterotoxin-producing strains of the bacterium Vibrio cholerae. The NIAID has characterized V. cholerae as a category 'B'-pathogen that poses a potential bioterrorism threat. Cholera is a waterborne disease and is associated with food consumption. For example, in the Americas, consumption of raw shellfish and raw vegetables has been associated with cholera outbreaks. In its most severe forms, cholera is one of the most rapidly fatal illnesses known, and a healthy person's blood pressure may drop to hypotensive levels within an hour of the onset of symptoms; infected patients may die within three hours if medical treatment or rehydration is not provided. In a common scenario, the disease progresses from the first liquid stool to shock in 4 to 12 hours, with death following in 18 hours to several days unless oral rehydration is provided. Massive liquid loss occurs after the cholera toxin (CT) first attaches to the gut epithelia via its B subunit (CTB), and then upon cell entry of its A subunit affects the electrolyte balance by activation of adenyl cyclase. There is no currently approved vaccine treatment for cholera available in the U.S. since strategies thus far have generally provided only variable, short-term immunity. Therefore, public health measures that prevent cholera, such as adequate sewage treatment and a reliable source of safe drinking water, are considered the most effective way of combating the disease. In this R21 proposal, we will develop and test in a suckling mouse model a biotechnology scaffold for protection against cholera infection. We will prepare Lactobacilli expressing an anti-CTB human single chain antibody fragment (scFv) as a bioadsorbent to remove CT from the gut. Our strategy is aimed at the clinical application of this Lactobacilli bioadsorbent, administered for example in yogurt, to either replace vaccination or for use as an adjunct passive immune therapy. We anticipate both its prophylactic utility and its use after initial exposure to the bacteria for the general public or, given the bioterrorism threat, Armed Forces Personnel and First responders. We will generate and test this new biotechnology scaffold under the remit of the following three specific aims: Specific aim #1: Selection of anti-CTB single chain antibody fragments from a human phage display library. Specific aim #2: Construction of Lactobacilli strains expressing a CTB-specific scFv antibody fragment. Specific aim #3: Studying the protective effect of gut colonization with a Lactobacilli strain expressing a CTB- specific scFv antibody against V. cholerae infection in mice. PUBLIC HEALTH RELEVANCE: In the United States, cholera was prevalent in the 1800s but has been virtually eliminated by modern sewage and water treatment systems. However, as a result of improved transportation, more persons from the United States travel to parts of Africa, Asia, or Latin America where epidemic cholera is occurring. U.S. travelers to areas with epidemic cholera may be exposed to the cholera bacterium. In addition, travelers may bring contaminated seafood back to the United States; foodborne outbreaks have been caused by contaminated seafood brought into this country by travelers. Cholera is such a problem in parts of the world that travelers from the US can receive a vaccine prior to travel. In this proposal we will develop an entirely new approach protect against cholera toxicity. We will develop a human antibody to cholera toxin and express it on Lactobacilli and colonize the gut with this biotechnology tool. It will be an invaluable tool for the traveler and first responders and armed forces personnel.

描述（由申请人提供）：霍乱，有时被称为亚洲或流行病霍乱，是一种由肠细菌霍乱霍乱的肠毒素引起的感染性胃炎。 NIAID将V.霍乱的特征描述为构成潜在的生物恐怖威胁的类别“ B'-Pathogen”。霍乱是一种水传播疾病，与食物消耗有关。例如，在美洲，生贝类和生蔬菜的消费与霍乱暴发有关。在最严重的形式中，霍乱是已知最快速致命的疾病之一，健康人的血压可能会在症状发作后一小时内降至降低水平。如果未提供医疗或补液，感染的患者可能会在三个小时内死亡。在常见的情况下，该疾病从第一次液体粪便到4到12小时内的冲击，除非提供口服再合化，否则在18小时至几天内死亡。大规模液体损失发生在霍乱毒素（CT）首先通过其B亚基（CTB）附着到肠上皮，然后在其A亚基的细胞进入后通过激活腺基环化酶来影响电解质平衡。目前尚无批准的霍乱疫苗治疗在美国可用，因为迄今为止的策略通常仅提供可变的短期免疫力。因此，预防霍乱的公共卫生措施，例如足够的污水处理和可靠的安全饮用水来源，被认为是打击疾病的最有效方法。 在此R21提案中，我们将在哺乳小鼠模型中开发和测试生物技术支架，以防止霍乱感染。我们将准备表达抗CTB人类单链抗体片段（SCFV）作为生物添加物的乳酸杆菌，以从肠道中去除CT。我们的策略旨在临床应用该乳酸杆菌生物助剂，例如在酸奶中给药，以取代疫苗接种或用作辅助性免疫治疗。我们预计它的预防效用及其在初次接触细菌的通用大众或生物恐怖主义威胁，武装部队人员和急救人员后的使用。 我们将在以下三个特定目的的角度下生成和测试这种新的生物技术支架：特定目的＃1：从人类噬菌体显示库中选择抗CTB单链抗体片段。特定目的＃2：表达CTB特异性SCFV抗体片段的乳杆菌菌株的结构。特定目的＃3：研究肠道菌菌株的保护作用，用乳酸菌株表达针对小鼠霍乱谷感染的CTB特异性SCFV抗体。 公共卫生相关性：在美国，霍乱在1800年代普遍存在，但现代污水和水处理系统实际上已经消除了霍乱。但是，由于运输的改善，更多的人来自美国的部分地区或拉丁美洲的部分流行病霍乱。美国前往流行霍乱地区的旅行者可能会暴露于霍乱细菌。此外，旅行者可能会将受污染的海鲜带回美国。食源性爆发是由旅行者带入该国的污染海鲜引起的。霍乱在世界各地是一个问题，以至于来自美国的旅行者可以在旅行前接种疫苗。在此提案中，我们将开发一种全新的方法，可以防止霍乱毒性。我们将开发一种对霍乱毒素的人类抗体，并在乳杆菌上表达它，并使用这种生物技术工具定居肠道。对于旅行者，急救人员和武装部队人员来说，它将是宝贵的工具。