Targeting Influenza A Virus by a Carbohydrate-inspired Strategy

项目摘要/摘要 蛋白质糖基化和碳水化合物介导的识别事件在 细胞间通信，它可以接触免疫系统的组件，并帮助维持 有机体的健康状态。不幸的是，许多病毒可以利用蛋白质的糖基化作用。在 在流感病毒的情况下，外壳蛋白血凝素(HA)介导病毒与唾液酸苷受体结合 宿主细胞，促进病毒和宿主膜的融合。由于蛋白质的复合型N-糖基化 被证明对流感病毒的传染性至关重要，推测的流感受体被认为是一种 糖蛋白。不幸的是，N-葡聚糖样品只占已建立的葡聚糖的一小部分 用于流感病毒研究的收藏品。不对称支化N-葡聚糖的可用性 样品对于开发下一代诊断工具和糖链测序具有重要意义 方法：研究方法。使用我们实验室开发的模块化方法，我们将扩展当前的N-糖链集合 结构。为了提高多聚糖阵列对流感病毒株的诊断能力，我们 将在氧化铝涂层玻璃(ACG)载玻片上创建N-葡聚糖阵列，因为这项技术能够实现更好的 与传统的N-羟基琥珀酰亚胺活化载玻片相比，对多糖密度和分布的控制； 允许检测即使是基于碳水化合物的微弱相互作用。 合成的N-葡聚糖样品将用于优化抗流感广谱中和抗体 FI6，从而协助FI6作为流感感染的普遍和高度有效的治疗方法的临床开发。这个 FI6的片段结晶(Fc)区在N297处含有一个N-糖链，它与FcγIIIa受体结合， 从而激活抗体依赖的细胞介导的细胞毒(ADCC)机制，以中和和 清除受感染的细胞。 目前的糖链构效关系(GSAR)主要是针对糖类构型建立的 双触角多聚糖，而含有四触角复合型N-多聚糖的蛋白糖体没有 尽管增加唾液酸化程度有望改善ADCC和 延长糖蛋白治疗药物的体内半衰期。我们打算通过准备工作来完成FI6的gSAR 含有三触角和四触角复合型N-糖链的糖型，以及神经氨酸酶抗性的N-糖链 衍生品。本研究产生的新方法和扩增的抗体gSAR将指导一般 设计其他针对癌症、艾滋病毒-1和其他病理情况的治疗性抗体，并将拥有 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.