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: 8033092
• 负责人: PAUL WENTWORTH
• 金额: $ 23.5万
• 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/8033092
• 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; 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(申请人提供)：霍乱，有时被称为亚洲霍乱或流行性霍乱，是一种由霍乱弧菌产生肠道毒素的菌株引起的传染性胃肠炎。NIAID将霍乱弧菌定为B类病原体，构成潜在的生物恐怖主义威胁。霍乱是一种通过水传播的疾病，与食物消费有关。例如，在美洲，生贝类和生蔬菜的消费与霍乱暴发有关。霍乱的最严重形式是已知的最迅速致命的疾病之一，健康人的血压可能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，受感染的患者可能在三小时内死亡。在一种常见的情况下，疾病从第一次液体大便发展到休克在4到12小时内，随后在18小时到几天内死亡，除非提供口服补液。霍乱毒素(CT)首先通过其B亚单位(CTB)附着在肠上皮细胞上，然后在其A亚单位进入细胞后通过激活腺苷环化酶影响电解质平衡，从而发生大量的液体丢失。美国目前还没有批准的霍乱疫苗治疗方法，因为到目前为止，这些策略通常只提供可变的短期免疫。因此，预防霍乱的公共卫生措施，如适当的污水处理和可靠的安全饮用水来源，被认为是抗击霍乱的最有效方法。在这份R21提案中，我们将开发一种生物技术支架，并在乳鼠模型中进行测试，以防止霍乱感染。我们将制备表达抗CTB人单链抗体片段(ScFv)的乳杆菌作为生物吸附剂，以去除肠道中的CT。我们的策略旨在将这种乳杆菌生物吸附剂应用于临床，例如在酸奶中使用，以取代疫苗接种或用作辅助被动免疫疗法。我们预计它的预防作用以及在公众首次接触细菌后使用它，或者考虑到生物恐怖主义的威胁，武装部队人员和急救人员。我们将在以下三个特定目标的范围内生成和测试这种新的生物技术支架：特定目标#1：从人噬菌体展示库中筛选抗CTB单链抗体片段。特定目的#2：构建表达CTB特异性单链抗体片段的乳杆菌菌株。具体目的#3：研究一株表达CTB特异性单链抗体的乳杆菌对霍乱弧菌感染小鼠的肠道定植保护作用。 与公共卫生相关：在美国，霍乱在19世纪盛行，但现代污水和水处理系统几乎消灭了霍乱。然而，由于交通的改善，更多的美国人前往发生霍乱疫情的非洲、亚洲或拉丁美洲的部分地区旅行。前往霍乱流行地区的美国旅行者可能会接触到霍乱细菌。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携带受污染的海鲜进入美国引起的。霍乱在世界部分地区是如此严重，以至于来自美国的旅行者可以在旅行前接种疫苗。在这项提案中，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，并将其在乳杆菌上表达，并使用这种生物技术工具在肠道中定植。对于旅行者、急救人员和武装部队人员来说，这将是一个无价的工具。