Strategies for generating high affinity antibodies against Gram negative bacteria

产生针对革兰氏阴性菌的高亲和力抗体的策略

• 批准号: 10117194
• 负责人: M.G. Finn
• 金额: $ 24.13万
• 依托单位: GEORGIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-02 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10117194
• 关键词: Address; Adjuvant; Affinity; Antibodies; Antibody Affinity; Antibody Response; Antibody-mediated protection; Antigens; B-Lymphocytes; Bacteria; Binding; Burkholderia; Burkholderia cepacia; Capsid; Carbohydrates; Cell surface; Cells; Clinical; Collaborations; Cytotoxic T-Lymphocytes; Development; Drug resistance; Effectiveness; Formulation; Generations; Germ-Line Mutation; Gram-Negative Bacteria; Growth; Health; Human; Immune; Immune response; Immune system; Immunoglobulin Class Switching; Immunoglobulin M; Immunologist; Immunology; Infection; Kinetics; Lead; Lung; Measures; Memory; Memory B-Lymphocyte; Methods; Modification; Molecular; Mus; Nucleotides; Oligosaccharides; Organism; Passive Immunization; Pathogenicity; Patients; Polysaccharides; Preparation; Process; Pseudomonas aeruginosa; Pseudomonas aeruginosa infection; Reagent; Research; Research Project Grants; Septic Shock; Site; Source; Specificity; Streptococcus pneumoniae; Structural Biologist; Structure; Surface; System; T-Lymphocyte; Testing; Therapeutic; Therapeutic Uses; Therapeutic antibodies; Vaccination; Vaccines; Virulent; Virus; Virus-like particle; adaptive immune response; antibody test; antimicrobial; base; chemical synthesis; chronic infection; cystic fibrosis infection; design; immunogenic; interest; mortality; mouse model; nanomolar; novel strategies; particle; passive antibodies; pathogen; response; screening; success; sugar; vaccine candidate; vaccine development; vaccine-induced antibodies

Project Summary Sugars cover the outer surfaces of bacteria and other pathogens and are usually very effective at shielding these organisms from the immune system. Lacking T cell help, anti-glycan responses are often of low affinity. Yet the structural complexity of oligosaccharides make them, in principle, excellent candidates for species-specific markers should specific immune recognition occur. The proposed research will use an approach for the generation of such immune responses against unique tri- and tetrasaccharide motifs found on the outer surfaces of dominant pathogenic strains of the Gram-negative bacteria Pseudomonas aeruginosa and Burkholderia cepacia. The method involves the chemical synthesis of the glycan motifs of interest in forms amenable to bioconjugation, the attachment of those molecules to immunogenic virus-like particles with precise control of the type and placement of the linkages used, and the use of a highly active activator of natural killer T (NKT) cells as adjuvant, these cells being central to the elicitation of robust immune responses against sugars in both natural infections and vaccines. This approach has been previously shown to generate ultra-high-affinity and protective antibody responses in mouse against Gram-positive Streptococcus pneumoniae. Gram-negative organisms remain a significantly tougher challenge; a potent immune response against pathogen- specific cell-surface glycan motifs could represent an effective response. The studies proposed here involve the creation and testing of eight candidate vaccine formulations against four carbohydrate motifs, two for each species. Screening of primary immune response will allow for optimization of the design and selection of final immunogens that will be carried into detailed studies. High-affinity antibodies generated from these agents will be further explored to determine their structures, binding affinities and kinetics, mutations from germ line, and abilities to protect against pathogen challenge in a relevant mouse model. Success in this endeavor would identify great potential for the development of human vaccines against these organisms and would provide confidence that the overall approach could be useful for other glycan-based vaccines.

项目摘要 糖覆盖在细菌和其他病原体的外表面，通常非常 有效地保护这些生物免受免疫系统的侵害。缺乏T细胞帮助，抗聚糖 响应通常具有低亲和力。然而，寡糖的结构复杂性使它们， 原则上，物种特异性标记的优秀候选者应该是特异性免疫识别的， 发生. 拟议的研究将使用一种方法来产生这种免疫反应， 针对在主要病原体的外表面上发现的独特的三糖和四糖基序， 革兰氏阴性菌铜绿假单胞菌和洋葱伯克霍尔德氏菌的菌株。的 该方法涉及以适合于合成的形式化学合成感兴趣的聚糖基序。 生物缀合，将这些分子附着到免疫原性病毒样颗粒上， 精确控制所用连杆的类型和位置，并使用高度活跃的 作为佐剂的自然杀伤T（NKT）细胞的激活剂，这些细胞是诱导免疫应答的核心。 在自然感染和疫苗中对糖的免疫反应都很强。 这种方法先前已被证明可以产生超高亲和力和保护性的 小鼠抗革兰氏阳性肺炎链球菌的抗体应答。兰阴性 微生物仍然是一个非常严峻的挑战;对病原体的有效免疫反应- 特异性细胞表面聚糖基序可以代表有效的应答。建议的研究 这涉及到八种候选疫苗配方的创建和测试， 碳水化合物基序，每个物种两个。初次免疫应答的筛查将允许 优化设计和选择最终的免疫原，将进行详细的 问题研究将进一步探索由这些试剂产生的高亲和力抗体，以确定 它们的结构，结合亲和力和动力学，来自种系的突变，以及保护 在相关小鼠模型中抵抗病原体攻击。 这一奋进的成功将确定人类发展的巨大潜力。 针对这些生物体的疫苗，并将提供信心， 可用于其他基于聚糖的疫苗。