Molecular basis of glycan recognition by T and B cells

摘要 虽然我们的PO1旨在将抗多糖免疫疗法定位为治疗严重细菌的新方法 疾病，我们将通过解构人的免疫识别来为其做出一些必要的基础研究 T细胞和B细胞的葡聚糖。这项工作是由化学小组(项目1、2和3)实现的，他们将 提供独特的免疫原和试剂，并与细菌学和结构生物学成分相适应 进行体内研究和结构测定。免疫学的整合 这一框架内的结果将使化学家了解如何修改葡聚糖表位及其与 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细胞识别多糖的分子基础。 我们已经证明T细胞对糖肽(GP)的同源识别发生了。我们将确定它的 在驱动高亲和力的抗多糖抗体和研究这些细胞的谱系多样性方面的重要性。这个 此外，还将探讨MHC-gp T细胞识别的生物物理和结构基础。我们假设 T细胞对同源糖链的识别对于推动高亲和力B细胞成熟具有重要意义。 目的2：建立B细胞识别多糖的分子基础。 我们将研究免疫后生发中心形成的动力学，并跟踪抗-HBs的成熟。 用抗原特异性试剂分离单个B细胞并对其测序获得高亲和力的B细胞 感受器。重组抗体表达后的生物物理研究，结合Core的结构努力 3应允许破译葡聚糖抗体识别的基本规则。这里，对囊膜抗原的识别 将与识别磷壁酸、肽多聚糖和O-连接的糖进行比较。 目的3：小鼠对葡聚糖的疫苗免疫应答效果。正如我们在标准中评估的那样 在建立抗多糖抗体保护能力的模型时，我们将疫苗与被动免疫疗法进行比较。 将用重组抗体来探索优化后一种干预的可能性，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，我们可以生产出针对细菌多糖的高亲和力的单抗 在挑战模型中，我们应该提供基本的机械洞察力来认识 B细胞和T细胞的糖链。我们的团队将在最具威胁性的 人的细菌感染：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.