Remodeling Salmonella outer membrane for vaccine development

重塑沙门氏菌外膜用于疫苗开发

• 批准号: 8384217
• 负责人: Qingke Kong
• 金额: $ 23.1万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-05 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8384217
• 关键词: Animals; Antibiotic Resistance; Antibodies; Antibody Formation; Arabinose; Attenuated; Bacteria; Bacterial Vaccines; CD8B1 gene; Cell Membrane Permeability; Cells; Cessation of life; Characteristics; Citrobacter rodentium; Disease; Down-Regulation; Engineering; Enteral; Enterobacteriaceae; Escherichia coli; Escherichia coli O157; Food Contamination; Gene Deletion; Gene Expression; Genes; Goals; Growth; Human; IgG1; Immune response; Immune system; Immunization; Immunoglobulin A; Immunoglobulin G; In Vitro; Invaded; Ions; Iron; Lamina Propria; Lead; Legal patent; Length; Life; Lipopolysaccharides; Lymphatic; Lymphoid Tissue; Manganese; Measures; Membrane; Membrane Proteins; Morbidity - disease rate; Mus; Mutation; O Antigens; Oligosaccharides; Organ; Outcome; Production; Protein S; Proteins; Quality of life; Rhamnose; Salmonella; Salmonella Vaccines; Salmonella typhimurium; Sampling; Secretory Immunoglobulin A; Series; Serum; Severity of illness; Shigella; Shigella flexneri; Specific qualifier value; Spleen; Structure; Systemic disease; Testing; Time; UNICEF; Vaccination; Vaccines; Vagina; Vesicle; Virulence; Water Supply; cost; enteric pathogen; immunogenic; immunogenicity; in vivo; mouse model; mutant; novel; pathogen; prevent; protective efficacy; research study; response; success; sugar; uptake; vaccine candidate; vaccine development

DESCRIPTION (provided by applicant): Attenuated live Salmonella vaccines have ability to induce antibodies cross-reactive to other enteric pathogens, particularly in strains engineered to achieve down-regulation of O-antigen synthesis in vivo. It is possible that if the Salmonella lipopolysaccharide (LPS) is truncated further, this may result in more effective presentation of conserved outer membrane proteins (OMPs) to the host immune system, which will lead to an immune response that is cross protective against a number of other Salmonella species and to other Gram- negative enteric pathogens. In addition, exposure of the fairly conserved core oligosaccharide and enhanced production of outer membrane vesicles may also aid in production of a cross-protective immune response. In this proposal, we will construct a series of mutations to achieve regulated O-antigen or core synthesis such that full length LPS is present at the time of immunization but is lost after colonization of the host. We will also include mutations that up-regulate expression of genes that specify essential ion uptake proteins including the iron regulated outer membrane proteins (IROMPs). Candidate vaccine strains will be further modified by introduction of other mutations including the pagC and ompX genes that are maximally up-regulated in vivo to promote outer membrane vesicles production to maximally induce antibodies cross-reactive to the OMPS of other enteric pathogens. The success of this project could lead to efficacious RASV with broad spectrum protection against enteric bacteria for human use. PUBLIC HEALTH RELEVANCE: Effective live bacterial vaccines hold the promise of providing low cost, orally administered, life-long protection against enteric bacteria. The goal of this project is to construct novel Salmonella vaccines to maximally expose conserved outer membrane proteins to the immune system to induce the higher cross-reactive antibodies to enteric bacteria via shutting off core oligosaccharide synthesis in vivo but retaining intact the LPS in vitro to facilitate invasion.

描述（由申请人提供）：减毒活沙门氏菌疫苗能够诱导与其他肠道病原体发生交叉反应的抗体，特别是在经过工程改造以实现体内 O 抗原合成下调的菌株中。如果沙门氏菌脂多糖（LPS）进一步截短，这可能会导致保守的外膜蛋白（OMP）更有效地呈递给宿主免疫系统，这将导致针对许多其他沙门氏菌物种和其他革兰氏阴性肠道病原体的交叉保护性免疫反应。此外，暴露相当保守的核心寡糖和增强外膜囊泡的产生也可能有助于产生交叉保护性免疫反应。在这个提案中，我们将构建一系列突变来实现受调节的O-抗原或核心合成，使得全长LPS在免疫时存在，但在宿主定植后丢失。我们还将包括上调特定必需离子摄取蛋白（包括铁调节外膜蛋白（IROMP））的基因表达的突变。候选疫苗株将通过引入其他突变（包括 pagC 和 ompX 基因）进行进一步修改，这些突变在体内最大限度地上调，以促进外膜囊泡的产生，从而最大限度地诱导与其他肠道病原体的 OMPS 发生交叉反应的抗体。该项目的成功可能会产生针对人类肠道细菌具有广谱保护作用的有效RASV。 公共卫生相关性：有效的活细菌疫苗有望提供低成本、口服、终身的肠道细菌保护。该项目的目标是构建新型沙门氏菌疫苗，最大限度地将保守的外膜蛋白暴露于免疫系统，通过关闭体内核心寡糖合成但在体外保留完整的脂多糖以促进入侵，诱导针对肠道细菌的更高交叉反应性抗体。