Elucidating the Structural Requirements for Next-Gen Glycoconjugate Vaccines

阐明下一代糖结合疫苗的结构要求 项目摘要 糖结合疫苗在全球范围内提供了巨大的健康益处，尽管它们的规模较小 在一些疾病高危人群中取得成功。在大多数情况下，糖的共轭 对载体蛋白的抗原是经验性的，几乎没有注意到对 免疫反应。我们实验室的最新发现为如何结合提供了一个新的合理的解释 工作。新的模型表明，通过抗原提呈细胞向T细胞递送碳水化合物可能 大大增强了抗体应答的效力。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感染链球菌疾病和图拉氏弗朗西斯杆菌感染， 结果产生了比标准糖结合疫苗更具保护性的疫苗。我们还演示了 多肽连接物和接合部位在提高接合效率和 对疫苗的免疫反应。结果支持了多肽糖结合疫苗提供 针对细菌挑战的卓越保护。值得注意的是，使用多肽而不是蛋白质作为 携带者在碳水化合物特异性免疫球蛋白水平低得多的情况下提供更好的保护。这一观察结果 挑战糖结合物诱导的免疫球蛋白与免疫球蛋白直接相关的范式 保护。蛋白质与多肽产生的抗体和免疫细胞的综合评价 糖偶联物将阐明使多肽疫苗极具效力的特征。我们将评估 糖肽疫苗在免疫球蛋白亚型、亲和力、亲和力和功能活性方面的抗体应答 以及阐明记忆B细胞上表达的共刺激/共抑制分子，并与 这与正在制造的抗体的功能有关。这种方法将定义使 糖肽诱导的抗体如此有效并构成筛选产生的B细胞杂交瘤的基础 从多肽和蛋白质的糖偶联物。高功能抗体与临界B细胞的相关性 生物标志物将被识别出来。产生具有不同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片段将被联合 与GBSIII寡糖结晶，研究表位特异性在保护中的作用。我们会 应用我们对这些多肽/多糖结合物的研究，创造更有效和更持久的 对糖结合疫苗的免疫力。好了！ 好了！

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. ! !