Fc glycan-modulated immunoglobulin G effector functions.
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.
Institute of Experimental Immunology, Department of Neuroinflammation, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland.
Isaak
I
Quast
Jan D
JD
Lünemann
D000818:Animals; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000276:immunology / Q000378:metabolism*; D007074:Immunoglobulin G / Q000276:immunology*; D016756:Immunoglobulins, Intravenous / Q000276:immunology* / Q000627:therapeutic use; D007167:Immunotherapy / Q000379:methods*; D007249:Inflammation / Q000276:immunology; D019158:N-Acetylneuraminic Acid / Q000276:immunology; D011134:Polysaccharides / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding / Q000276:immunology
D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous; D011134:Polysaccharides; D019158:N-Acetylneuraminic Acid