Targeting Influenza A Virus by a Carbohydrate-inspired Strategy

项目总结/摘要 蛋白质糖基化和碳水化合物介导的识别事件在蛋白质合成过程中起着重要作用。 细胞间通讯，它可以参与免疫系统的组成部分，并帮助维持一个 机体的健康状态。不幸的是，许多病毒可以利用蛋白质糖基化。在 在流感病毒的情况下，外壳蛋白血凝素（HA）介导病毒结合至细胞膜的唾液酸苷受体。 宿主细胞并促进病毒和宿主膜的融合。由于蛋白质的复合型N-糖基化 被证明是至关重要的流感病毒的传染性，推定的流感受体被认为是一个 糖蛋白不幸的是，N-聚糖样品仅占已确定聚糖的一小部分 用于流感病毒研究的标本。不对称分支N-聚糖的可用性 样品有助于开发下一代诊断工具和聚糖测序 方法.使用本实验室开发的模块化方法，我们将扩展现有的N-聚糖集合 结构.为了提高聚糖阵列用于流感病毒株谱分析的诊断能力，我们 将在氧化铝涂层玻璃（ACG）载玻片上创建N-聚糖阵列，因为该技术可以更好地 与常规N-羟基琥珀酰亚胺活化载玻片相比，对聚糖密度和分布的控制;以及 允许检测甚至微弱的基于碳水化合物的相互作用。 N-聚糖的合成样品将用于优化抗流感广泛中和抗体 FI 6，从而有助于FI 6作为流感感染的通用和高效治疗剂的临床开发。的 FI 6的片段可结晶（Fc）区在N297处含有单个N-聚糖，其接合FcγIIIa受体， 从而激活抗体依赖性细胞介导的细胞毒性（ADCC）机制进行中和， 清除感染细胞。 目前的聚糖结构-活性关系（gSAR）主要是针对以下糖型建立的： 双触角聚糖，而含有四触角复合型N-聚糖的蛋白糖型不具有 尽管如此，增加唾液酸化的程度预计会改善ADCC， 延长糖蛋白治疗剂的体内半衰期。我们打算通过准备以下内容来完成FI 6的gSAR 具有三触角和四触角复合型N-聚糖的糖型，以及耐神经氨酸酶的N-聚糖 衍生物.这项研究产生的新方法和扩展的抗体gSAR将指导一般的 设计靶向癌症、HIV-1和其他病理状况的其他治疗性抗体， 对公众健康有直接影响。

PROJECT SUMMARY/ABSTRACT Protein glycosylation and carbohydrate-mediated recognition events play a major role during intercellular communications, which can engage components of the immune system and help maintain a healthy state of the organism. Unfortunately, many viruses can take advantage of protein glycosylation. In the case of influenza virus, the coat protein hemagglutinin (HA) mediates virus binding to sialoside receptors of the host cell and facilitates the fusion of viral and host membranes. Since complex-type N-glycosylation of proteins was shown to be crucial for the influenza virus infectivity, the putative influenza receptor is believed to be a glycoprotein. Unfortunately, N-glycan samples occupy only a small percentage of the established glycan collections that are used in the study of influenza virus. The availability of asymmetrically branched N-glycan samples is instrumental to the development of the next generation diagnostic tools and glycan sequencing methods. Using the modular method developed by our lab, we will expand the current collections of N-glycan structures. In order to improve diagnostic capabilities of glycan arrays for the profiling of influenza strains, we will create N-glycan arrays on the aluminium oxide coated glass (ACG) slides as this technology enables better control over the glycan density and distribution than conventional N-hydroxysuccinimide activated slides; and allows detection of even weak carbohydrate-based interactions. Synthetic samples of N-glycans will be used to optimize the anti-influenza broadly neutralizing antibody FI6, thus assisting clinical development of FI6 as universal and highly potent therapeutics of flu infection. The fragment crystallizable (Fc) region of FI6 contains a single N-glycan at N297, which engage FcγIIIa receptor, thus activating the antibody-depended cell-mediated cytotoxicity (ADCC) mechanism for neutralization and clearance of the infected cells. The current glycan structure-activity relationship (gSAR) is mostly established for the glycoforms with bi-antennary glycans, whereas protein glycoforms containing tetra-antennary complex-type N-glycans have not been accessed yet, even though, increasing the degree of sialylation is expected to improve ADCC and prolong in vivo half-life of glycoprotein therapeutics. We intend to complete the gSAR of FI6 by preparing glycoforms with tri- and tetra-antennary complex-type N-glycans, as well as neuraminidase-resistant N-glycan derivatives. New methods generated by this research and the expanded antibody gSAR will guide the general design of other therapeutic antibodies targeting cancer, HIV-1 and other pathological conditions, and will have a direct impact on public health.