Molecular basis of glycan recognition by T and B cells

摘要 虽然我们的PO 1旨在将抗聚糖免疫疗法定位为治疗严重细菌性肺炎的新方法， 疾病，我们将贡献一些必要的基础研究，它通过解构免疫识别， T和B细胞对聚糖的作用。这项工作是由化学小组（项目1，2和3）谁将成为可能 提供独特的免疫原和试剂，将适合细菌学和结构生物学组件 进行体内研究和结构测定。免疫学的整合 该框架内的结果将告知化学家如何修饰聚糖表位及其连接， 优化免疫识别和体内效应器功能。我们的努力将分为三个具体目标： 目的1：建立T细胞识别糖链的分子基础。 我们已经表明，同源识别的糖肽（GP）的T细胞发生。我们将确定其 在驱动高亲和力抗聚糖抗体和研究这些细胞的库多样性中的重要性。的 还将检查MHC-GP T细胞识别的生物物理和结构基础。我们假设 T细胞对同源聚糖的识别对于驱动高亲和力B细胞成熟是重要的。 目的2：建立B细胞识别糖链的分子基础。 我们将检查免疫后生发中心形成的动力学，并跟踪抗- 通过用抗原特异性试剂分离单个B细胞并对其进行测序， 受体。抗体重组表达后的生物物理学研究，与Core的结构努力配对 3应该允许破译聚糖抗体识别的基本规则。在这里，对荚膜抗原的识别 将与磷壁酸、肽聚糖和O-连接的β-葡聚糖的识别进行比较。 目的3：小鼠中对聚糖的疫苗免疫应答的有效性。正如我们在标准评估 为了模拟抗聚糖抗体的保护能力，我们将比较疫苗和被动免疫疗法。 优化后一种干预的可能性将用重组抗体进行探索，目的是避免 金黄色葡萄球菌挫败B细胞反应的能力。 虽然我们已经证明，我们可以产生高亲和力的单克隆抗体对细菌聚糖 保护性挑战模型，在这里，我们应该提供基本的机械见解的认识， 由B和T细胞产生的。我们的团队将在最具威胁性的环境中挑战这一知识 人类细菌感染：金黄色葡萄球菌。

Abstract While our PO1 aims at positioning anti-glycan immunotherapy as a new approach to treat severe bacterial diseases, we will contribute some essential basic studies to it by deconstructing the immune recognition of glycans by T and B cells. This work is made possible by the chemistry groups (Projects 1, 2, and 3) who will provide unique immunogens and reagents and will fit next to the bacteriology and structural biology components of the consortium to perform in vivo studies and structure determinations. The integration of the immunology results within this framework will inform the chemists on how to modify glycan epitopes and their linkages to optimize immune recognition and in vivo effector functions. Our effort will be divided between three specific aims: Aim 1: Establish the molecular basis of glycan recognition by T cells. We have shown that cognate recognition of the glycopeptide (GP) by T cells occurred. We will determine its importance in driving high affinity anti-glycan antibodies and study the repertoire diversity of these cells. The biophysical and structural basis of MHC-GP T cell recognition will be examined as well. We hypothesize that cognate glycan recognition by T cells is important for driving high affinity B cell maturation. Aim 2: Establish the molecular basis of glycan recognition by B cells. We will examine the kinetics of germinal center formation upon immunization and follow the maturation of anti- glycan B cells towards high affinity by isolating single B cells with antigen specific reagents and sequencing their receptors. Biophysical studies after recombinant expression of antibodies, paired with the structural effort of Core 3 should allow to decipher the basic rules of glycan antibody recognition. Here, recognition of capsular antigens will be compared to the recognition of teichoic acids, peptidoglycans and O-linked saccharides. Aim 3: Effectiveness of the vaccinal immune response to glycan in mice. As we evaluate in standard models the protection capacity of anti-glycan antibodies, we will compare vaccine to passive immunotherapy. The possibility to optimize this latter intervention will be explored with recombinant antibodies aimed at avoiding Staphylococcus aureus ability to foil the B cell response. While we have shown that we could produce monoclonal antibodies of high affinity against bacterial glycans protective in challenges models, here, we should provide fundamental mechanistic insights into the recognition of glycans by B and T cells. Our team will challenge this knowledge in the context of one of the most threatening bacterial infections of man: Staphylococcus aureus.