Glycoengineering In Vivo

描述（由申请人提供）：碳水化合物被添加并进一步修饰到通过分泌途径的蛋白质中。负责这些添加和修饰的酶跨越细胞膜并延伸到细胞蛋白质加工中心的管腔、内质网和高尔基体。一般来说，糖基化对于维持或促进蛋白质稳定性或与碳水化合物特异性受体相互作用很重要。我们体内产生的大多数蛋白质都是糖基化的，或通过糖的附着进行修饰，包括循环中的可溶性蛋白质和细胞表面的受体。糖基化在健康和疾病中的重要性日益受到重视。许多成功的病原体，包括艾滋病毒和结核分枝杆菌，将自己包裹在聚糖中以躲避免疫系统。干细胞运输是由糖基化控制的。红细胞ABO型由糖基化决定。此外，免疫球蛋白效应的功能受糖基化控制。令人惊讶的是，尽管糖基化发挥着许多独特的生物学作用，但人们对其调控知之甚少。进一步的操作糖基化的尝试使用了粗糙的体外系统，其范围和适用性有限。推动医学进步的分子生物学革命掩盖了糖生物学的这些缺陷。有趣的是，许多附着和改变聚糖的分泌途径酶被分泌到循环中。本研究旨在利用糖基化酶的天然可溶性形式，实现体内可溶性蛋白和表面受体的糖工程。这些研究将能够检查特定的聚糖修饰。此外，我们将探索糖工程的治疗潜力。例如，参与艾滋病毒和流感发病机制的聚糖将被改变以抑制感染，抗体将在循环中被改造，所有的红细胞将被转化为通用的O型供体。因此，这一建议将破译特定聚糖对单个蛋白质的生物学贡献，可能影响一系列疾病类型。

DESCRIPTION (provided by applicant): Carbohydrates are added and further modified to proteins passing through the secretory pathway. The enzymes responsible for these additions and modifications span the membranes and extend in the lumen of the protein processing centers of the cell, the endoplasmic reticulum and Golgi apparatus. In general, glycosylation is important for either maintaining or promoting protein stability, or enabling interactions with carbohydrate-specific receptors. Most proteins produced in our bodies are glycosylated, or modified by the attachment of sugars, include soluble proteins in circulation and receptors on the surface of cells. The importance of glycosylation in health and disease is increasingly appreciated. Many successful pathogens, including HIV and Mycobacterium tuberculosis, cover themselves in glycans to hide from the immune system. Stem cell trafficking is controlled by glycosylation. The red blood cell ABO types are determined by glycosylation. Also, immunoglobulin effector functions are controlled by glycosylation. Surprisingly, little is known about the regulation of glycosylation, despite the many distinct biological roles it plays. Further attempts to manipulate glycosylation have used crude, in vitro systems, which are limited in scope and applicability. The molecular biology revolution that drives medicine forward has overshadowed these deficiencies in glycobiology. Intriguing, many of the secretory pathway enzymes that attach and alter glycans are secreted into the circulation. This proposal aims exploit the natural soluble forms of glycosylation enzymes, enabling glycoengineering of soluble proteins and surface receptors in vivo. These studies will enable examination of specific glycan modification. Further, we will explore the therapeutic potential of glycoengineering. For example, glycans involved in HIV and Influenza pathogenesis will be altered to curb infections, antibodies will be engineered in the circulation, and all red blood cells will be converted into universal typ O donors. Thus, this proposal will decipher the biological contribution of specific glycans on individual proteins, potentially impacting a range of disease types.