Elucidating the Structural Requirements for Next-Gen Glycoconjugate Vaccines

阐明下一代糖复合疫苗的结构要求

• 批准号: 10084269
• 负责人: Dennis L. Kasper
• 金额: $ 60.46万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-10 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10084269
• 关键词: Affinity; Antibodies; Antibody Affinity; Antibody Avidity; Antibody Response; Antibody titer measurement; Antibody-mediated protection; Antigen-Presenting Cells; Antigens; Attention; Avidity; B-Lymphocytes; B-cell receptor repertoire sequencing; Binding; Biological Markers; CD4 Positive T Lymphocytes; Carbohydrates; Carrier Proteins; Cells; Characteristics; Complex; Crystallization; Data; Disease; Epitopes; Evaluation; Event; Fab Immunoglobulins; Generations; Genetic Transcription; Glycoconjugates; Glycopeptides; Glycoproteins; Health Benefit; Helper-Inducer T-Lymphocyte; Histocompatibility Antigens Class II; Hybridomas; Immune; Immune response; Immunity; Immunization; Immunize; Immunoglobulin G; Immunologics; Link; Mediating; Memory B-Lymphocyte; Modeling; Molecular Weight; Monoclonal Antibodies; Oligosaccharides; Peptide Vaccines; Peptides; Polysaccharides; Population; Production; Proteins; Role; Site; Specificity; Streptococcus Group B; Structure; Surface; T-Lymphocyte; Tularemia; Vaccines; Work; adaptive immune response; alpha-beta T-Cell Receptor; base; design; high risk; insight; mouse model; pathogen; response; screening; sugar; vaccine-induced antibodies

Elucidating the Structural Requirements for Next-Gen Glycoconjugate Vaccines Project Summary Glycoconjugate vaccines provide enormous health benefits globally, although they have been less successful in some populations at high risk for developing disease. In most cases, conjugation of the sugar antigen to the carrier protein has been done empirically with little attention on variables critical for the immune response. Recent findings from our lab offer a new and rational explanation for how conjugates work. The new model suggests that carbohydrate presentation to T cells by antigen-presenting cells may strongly enhance the efficacy of antibody responses. Application of this principle in mouse models of group B streptococcal disease and Francisella tularensis infection by using a carrier peptide rather than a protein, resulted in vaccines more protective than standard glycoconjugate vaccines. We have also demonstrated the critical role of the peptide linker and the conjugation site in enhancing both the conjugation efficiency and the immune response to vaccines. The results support the notion that peptide glycoconjugate vaccines provide superior protection against bacterial challenges. Remarkably, the use of a peptide instead of a protein as a carrier confers better protection at much lower levels of carbohydrate specific IgG. This observation challenges the paradigm of a direct correlation between the amount of IgG induced by a glycoconjugate and protection. A comprehensive evaluation of antibodies and immune cells generated by protein vs peptide glycoconjugates will clarify the features that make peptide vaccines extremely potent. We will evaluate the antibody response to glycopeptide vaccines in terms of IgG subtypes, affinity, avidity and functional activity, as well as, elucidate the costimulatory/coinhibitory molecules being expressed on memory B cells and relate this to the functionality of the antibodies being made. This approach will define the characteristics that make glycopeptide-induced antibodies so potent and forms the basis for screening of B-cell hybridomas produced from peptide vs protein glycoconjugates. Correlates of highly functional antibody and critical B cell biomarkers will be identified. Hybridomas that produce antibodies with different degrees of protective activity will be evaluated by BCR sequencing. Fab fragments of low and highly effective antibodies will be co- crystallized with GBSIII oligosaccharide to investigate the role of epitope specificity in protection. We will apply our studies of these peptide/polysaccharide conjugates to create more efficacious and longer lasting immunity to glycoconjugate vaccines. ! !

阐明下一代糖复合疫苗的结构要求 项目概要 糖复合疫苗在全球范围内提供了巨大的健康益处，尽管其效果较差 在一些患病高风险人群中取得了成功。在大多数情况下，糖的结合 载体蛋白的抗原是凭经验完成的，很少关注对载体蛋白至关重要的变量 免疫反应。我们实验室的最新研究结果为缀合物如何发挥作用提供了新的合理解释 工作。新模型表明，抗原呈递细胞向 T 细胞呈递碳水化合物可能 强烈增强抗体反应的功效。该原理在B组小鼠模型中的应用 通过使用载体肽而不是蛋白质来治疗链球菌疾病和土拉弗朗西斯菌感染， 导致疫苗比标准糖复合物疫苗更具保护性。我们还展示了 肽接头和缀合位点在增强缀合效率和 对疫苗的免疫反应。结果支持肽糖复合物疫苗提供的观点 针对细菌挑战的卓越保护。值得注意的是，使用肽代替蛋白质作为 载体以低得多的碳水化合物特异性 IgG 水平提供更好的保护。这一观察 挑战了糖缀合物诱导的 IgG 量与 保护。蛋白质与肽产生的抗体和免疫细胞的综合评估 糖复合物将阐明使肽疫苗极其有效的特征。我们将评估 糖肽疫苗的抗体反应，包括 IgG 亚型、亲和力、亲合力和功能活性， 以及阐明在记忆 B 细胞上表达的共刺激/共抑制分子并将 这与所制备的抗体的功能有关。这种方法将定义使 糖肽诱导的抗体非常有效，为筛选产生的 B 细胞杂交瘤奠定了基础 来自肽与蛋白质糖缀合物。高功能抗体与关键 B 细胞的相关性 将鉴定生物标志物。产生具有不同程度保护活性的抗体的杂交瘤 将通过 BCR 测序进行评估。低效和高效抗体的 Fab 片段将被共 用 GBSIII 寡糖结晶，研究表位特异性在保护中的作用。我们将 应用我们对这些肽/多糖缀合物的研究来创造更有效和更持久的 对糖复合物疫苗的免疫力。 ！ ！