Reverse vaccinology of enterotoxigenic E. coli

产肠毒素大肠杆菌的反向疫苗学

• 批准号: 8589931
• 负责人: Philip Ross Hardwidge
• 金额: $ 18.75万
• 依托单位: KANSAS STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8589931
• 关键词: Reverse; vaccinology; enterotoxigenic; E.; coli

DESCRIPTION (provided by applicant): Significance of the proposed research. Diarrheal disease caused by enteric bacteria is an important endemic health threat and a major source of food-borne disease. Diarrheal pathogens also remain an important health concern in current military operations and in bioterrorism. In spite of the appreciated magnitude of the threat to both general human health and the severe inhibition of military performance caused by ETEC, we still do not have an effective vaccine, nor do we fully understand the virulence determinants responsible for intestinal colonization and subsequent diarrheal disease. Basic research is needed to identify new therapeutic and vaccine targets. The objective of this application is to use quantitative proteomic protein profiling to discover broadly conserved antigens that will permit development of a vaccine efficacious against ETEC. The primary need that motivates this research objective is that despite the significant effort and expense that has been employed in vaccine trials using ETEC adhesins, none of these vaccines have been especially effective in mediating cross- protective immunity, and some trials have even had significant health risks. Alternative vaccine targets and strategies are demanded. We will utilize our proven experience in ETEC microbiology and quantitative proteomics to characterize novel ETEC vaccine antigens. We will do this by identifying novel surface-exposed ETEC proteins likely to be recognized by the host immune system. We show in preliminary studies that the proposed approach rapidly and economically identifies conserved, surface-exposed ETEC proteins, independent of strain-specific CFs, which can be purified and used in protection assays in a robust animal model of ETEC virulence. The specific aims are to: 1) Characterize ETEC outer membrane proteomes using quantitative proteomic profiling, 2) Produce recombinant ETEC proteins and antisera, and 3) Immunize mice with recombinant ETEC antigens and quantify their ability to protect against an otherwise lethal challenge with ETEC. The proposed research is significant and innovative because it introduces a novel strategy for protective antigen discovery for a neglected pathogen responsible for causing an enormous global diarrheal disease burden. Indeed, we have already discovered seventeen surface-exposed antigens that are potential components of a new ETEC vaccine formulation. Additionally, these experiments will optimize proteomic strategies needed to characterize vaccine candidates in other enteric pathogens.

描述（由申请人提供）：拟议研究的重要性。由肠道细菌引起的腹泻病是重要的流行健康威胁，也是粮食传播疾病的主要来源。腹泻病原体在当前的军事行动和生物恐怖主义中仍然是重要的健康问题。尽管对一般人类健康的威胁和对ETEC引起的军事绩效的严重抑制也具有人们的理解，但我们仍然没有有效的疫苗，我们也完全不了解导致肠道定殖和随后腹泻病的毒力决定因素。需要基础研究来识别新的治疗和疫苗靶标。 该应用的目的是使用定量蛋白质组学蛋白分析来发现广泛保守的抗原，这将允许开发疫苗对ETEC的有效性。激发这一研究目标的主要需求是，尽管使用ETEC粘附素进行了疫苗试验中采用的巨大努力和费用，但这些疫苗都没有在介导交叉保护性免疫方面特别有效，并且一些试验甚至具有重大的健康风险。需要替代疫苗目标和策略。 我们将利用我们在ETEC微生物学和定量蛋白质组学方面的经验丰富的经验来表征新型ETEC疫苗抗原。我们将通过鉴定出可能被宿主免疫系统识别的新型表面暴露ETEC蛋白来做到这一点。我们在初步研究中表明，所提出的方法在经济上迅速鉴定出了保守的，表面暴露的ETEC蛋白，与菌株特异性CF无关，这些CFS可以纯化并在强大的ETEC毒力模型中纯化并用于保护测定中。 具体目的是：1）使用定量蛋白质组学分析表征ETEC外膜蛋白质组织，2）产生重组ETEC蛋白和抗血清，以及3）3）用重组ETEC抗原进行免疫小鼠，并量化其对ETEC的杀伤性挑战的能力。 拟议的研究具有重要意义和创新性，因为它引入了一种新型的保护性抗原发现的策略，该策略是一种忽视的病原体，负责造成巨大的全球腹泻疾病负担。确实，我们已经发现了17种表面暴露的抗原，它们是一种新的ETEC疫苗配方的潜在成分。此外，这些实验将优化在其他肠道病原体中表征候选疫苗所需的蛋白质组学策略。