Heterologous polysaccharide synthesis in attenuated Salmonella

减毒沙门氏菌中异源多糖的合成

基本信息

批准号：
8836815
负责人：
Qingke Kong
金额：
$ 18.55万
依托单位：
ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-01 至 2016-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8836815
关键词：
Adjuvant Adult Animals Antibodies Antigen Targeting Antigens Arabinose Attenuated Bacterial Infections Bacterial Polysaccharides Bacterial Proteins Binding Sites Campylobacter jejuni Carbohydrates Carrier Proteins Cell Membrane Permeability Cell surface Cells Characteristics Chemicals Child Cloning Complex Conjugate Vaccines DNA DNA Vaccines Distal Down-Regulation Elderly Engineering Equilibrium Gene Expression Generations Genes Genetic Goals Gram-Positive Bacteria Growth Heterophile Antigens Immune response Immunity Immunization Immunoglobulin A Immunoglobulin G In Vitro Infection Injection of therapeutic agent Legal patent Length Life Link Lipid A Lipopolysaccharides Lymphoid Tissue Memory Memory B-Lymphocyte Methods Modification Mus Needles O Antigens Operon Oryctolagus cuniculus Outcome Plasmid Cloning Vector Polysaccharides Population Property Proteins Quality of life Recombinants Safety Salmonella Salmonella typhimurium Series Serum Site Structure Surface System T-Lymphocyte Technology Time Tissues Toxic effect United States National Institutes of Health Vaccines Virulence Virulent Work Yeasts base cell mediated immune response cost design design and construction dolichyl-diphosphooligosaccharide - protein glycotransferase extracellular genetic manipulation glycosylation homologous recombination immunogenicity improved in vivo innovation macromolecule mutant novel novel strategies pathogen pathogenic bacteria periplasm prevent public health relevance research study response sugar vaccine development

项目摘要

DESCRIPTION (provided by applicant): Polysaccharide (PS) constitutes one of major classes of bio-macromolecules covering the surface of the bacterial pathogens, representing a major virulent determinant and immunogen. Several PS vaccines (including conjugated PS) have been developed to prevent the pathogen infections; these PS vaccines suffer from low yields, non-specific chemical conjugation, high costs, and delivery by injection. Recombinant attenuated Salmonella (RAS) are capable of delivering heterologous antigens, including PS, from a variety of pathogens, generating a range of immune responses including serum antibodies, mucosal IgA, and a panoply of cell-mediated immune responses at local and distal sites. These RAS are designed and constructed to deliver protein or DNA antigens. In this work, we undertake the construction of attenuated Salmonella strains designed specifically for delivery of bacterial PS antigens, including O-antigen polysaccharides (O-PS) from Gram-negative pathogens and capsular polysaccharides (C-PS) from Gram-positive pathogens. In our strains, these complex carbohydrates will be covalently linked to the Salmonella cell surface. Using our novel regulated delayed gene expression technology, all native Salmonella surface carbohydrates will be present at the time of immunization to facilitate Salmonella-host interactions necessary for optimal immunogenicity, but will be down-regulated in vivo, after colonization of host lymphatic tissues. Conversely, synthesis of heterologous carbohydrates will not occur until after the vaccine strain has colonized host tissues. Down-regulation of Salmonella carbohydrates will permit optimal expression and presentation of heterologous carbohydrates without interference or steric blocking by Salmonella surface structures. Linking the target polysaccharide antigens to the Salmonella cell surface provides the strong adjuvant effects of Salmonella LPS. In addition, these "biologically conjugated polysaccharide vaccines" will allow us to take advantage of the known ability of traditional, chemically conjugated polysaccharide antigens to stimulate both T-cell dependent and T-cell independent immune responses to the target antigen.

描述（由申请人提供）：多糖（PS）构成了覆盖细菌病原体表面的生物大分子的主要类别，代表了主要的有毒物的决定因素和免疫原。已经开发了几种PS疫苗（包括共轭PS），以防止病原体感染。这些PS疫苗的产量低，非特异性化学结合，高成本和注射量。重组减毒沙门氏菌（RAS）能够从多种病原体中输送包括PS的异源抗原，产生一系列免疫反应，包括血清抗体，粘膜IGA和远端和远端部位的细胞介导的免疫反应。这些RA的设计和构建以递送蛋白质或DNA抗原。在这项工作中，我们进行了专门为细菌PS抗原提供的减毒沙门氏菌菌株的构建，包括从革兰氏阴性病原体和囊膜多糖（C-PS）中的O-抗原多糖（O-PS）构建。在我们的菌株中，这些复杂的碳水化合物将与沙门氏菌细胞表面共价关联。使用我们新颖的受调节的延迟基因表达技术，所有天然沙门氏菌表面碳水化合物都将在免疫时出现，以促进沙门氏菌宿主相互作用，以促进最佳免疫原性所需的相互作用，但在宿主淋巴组织的定殖后，将在体内下调。相反，直到疫苗菌株定居宿主组织后，异源碳水化合物的合成才会发生。沙门氏菌碳水化合物的下调将允许最佳表达和呈现异源碳水化合物，而不会干扰或通过沙门氏菌表面结构阻塞。将目标多糖抗原与沙门氏菌细胞表面联系起来，可提供沙门氏菌LPS的强佐剂作用。此外，这些“生物结合的多糖疫苗”将使我们能够利用传统的化学共轭多糖抗原的已知能力，以刺激对靶抗原的T细胞依赖性和T细胞独立的免疫反应。