Quast Isaak, Lünemann Jan D
Institute of Experimental Immunology, Department of Neuroinflammation, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland.
J Clin Immunol. 2014 Jul;34 Suppl 1:S51-5. doi: 10.1007/s10875-014-0018-3. Epub 2014 Apr 24.
Immunoglobulin G (IgG) molecules are glycoproteins and residues in the sugar moiety attached to the IgG constant fragment (Fc) are essential for IgG functionality such as binding to cellular Fc receptors and complement activation. The core of this sugar moiety consists of a bi-antennary heptameric structure of mannose and N-acetylglucosamine (GlcNAc), further decorated with terminal and branching residues including galactose, sialic acid, fucose, and GlcNAc. Presence or absence of distinct residues such as fucose and sialic acid can dramatically alter pro- and anti-inflammatory IgG activities which could be harnessed for immunotherapeutic purposes. Here we review recent advances in understanding the role of the IgG-Fc glycan during immune responses and for immunotherapy with a focus on sialic acid and intravenous immunoglobulin (IVIG) treatment.
免疫球蛋白G（IgG）分子是糖蛋白，附着于IgG恒定片段（Fc）的糖部分中的残基对于IgG的功能至关重要，例如与细胞Fc受体结合和补体激活。该糖部分的核心由甘露糖和N-乙酰葡糖胺（GlcNAc）的双触角七聚体结构组成，进一步被包括半乳糖、唾液酸、岩藻糖和GlcNAc在内的末端和分支残基修饰。岩藻糖和唾液酸等特定残基的存在与否可显著改变促炎和抗炎IgG活性，这可用于免疫治疗目的。在此，我们综述了在理解IgG-Fc聚糖在免疫反应中的作用以及免疫治疗方面的最新进展，重点关注唾液酸和静脉注射免疫球蛋白（IVIG）治疗。
