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，有时称为亚洲霍乱或流行性霍乱，是一种由产肠毒素的霍乱弧菌菌株引起的传染性胃肠炎。 NIAID 将霍乱弧菌定性为“B”类病原体，具有潜在的生物恐怖主义威胁。霍乱是一种水传播疾病，与食物消耗有关。例如，在美洲，食用生贝类和生蔬菜与霍乱爆发有关。在最严重的情况下，霍乱是已知的最迅速致命的疾病之一，健康人的血压可能会在症状出现后一小时内降至低血压水平；如果不提供医疗或补液，受感染的患者可能会在三小时内死亡。在常见情况下，疾病从第一次稀便在 4 至 12 小时内发展为休克，除非提供口服补液，否则在 18 小时至几天内死亡。霍乱毒素 (CT) 首先通过其 B 亚基 (CTB) 附着在肠道上皮细胞上，然后在其 A 亚基进入细胞后通过激活腺苷酸环化酶影响电解质平衡，从而发生大量液体损失。美国目前尚无批准的霍乱疫苗治疗方法，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，例如充分的污水处理和可靠的安全饮用水源，被认为是对抗该疾病的最有效方法。 在这个 R21 提案中，我们将在乳鼠模型中开发和测试一种用于预防霍乱感染的生物技术支架。我们将制备表达抗 CTB 人单链抗体片段 (scFv) 的乳酸杆菌作为生物吸附剂，以去除肠道中的 CT。我们的策略旨在临床应用这种乳酸菌生物吸附剂，例如在酸奶中给药，以替代疫苗接种或用作辅助被动免疫疗法。我们预计它的预防效用以及在公众或考虑到生物恐怖主义威胁的武装部队人员和急救人员初次接触细菌后的使用。 我们将在以下三个具体目标的范围内生成并测试这种新的生物技术支架：具体目标#1：从人噬菌体展示库中选择抗CTB单链抗体片段。具体目标#2：构建表达 CTB 特异性 scFv 抗体片段的乳杆菌菌株。具体目标#3：研究表达CTB特异性scFv抗体的乳杆菌菌株对小鼠肠道定植对霍乱弧菌感染的保护作用。 公共卫生相关性：在美国，霍乱在 1800 年代盛行，但已被现代污水和水处理系统几乎消除。然而，由于交通条件的改善，越来越多的美国人前往霍乱流行的非洲、亚洲或拉丁美洲部分地区。前往霍乱流行地区的美国旅行者可能会接触霍乱细菌。此外，旅行者可能会将受污染的海鲜带回美国；食源性疫情是由旅行者带入该国的受污染海鲜引起的。霍乱在世界部分地区是一个严重的问题，来自美国的旅行者可以在旅行前接种疫苗。在本提案中，我们将开发一种全新的方法来预防霍乱毒性。我们将开发一种针对霍乱毒素的人类抗体，并在乳酸杆菌上表达它，并利用这种生物技术工具在肠道中定殖。对于旅行者、急救人员和武装部队人员来说，这将是一个非常宝贵的工具。