title: The Emerging Importance of IgG Fab Glycosylation in Immunity.
abstract: Human IgG is the most abundant glycoprotein in serum and is crucial for protective immunity. In addition to conserved IgG Fc glycans, ∼15-25% of serum IgG contains glycans within the variable domains. These so-called "Fab glycans" are primarily highly processed complex-type biantennary N-glycans linked to N-glycosylation sites that emerge during somatic hypermutation. Specific patterns of Fab glycosylation are concurrent with physiological and pathological conditions, such as pregnancy and rheumatoid arthritis. With respect to function, Fab glycosylation can significantly affect stability, half-life, and binding characteristics of Abs and BCRs. Moreover, Fab glycans are associated with the anti-inflammatory activity of IVIgs. Consequently, IgG Fab glycosylation appears to be an important, yet poorly understood, process that modulates immunity.
authors: Department of Immunopathology, Sanquin Research, 1066 CX Amsterdam, the Netherlands; Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands;
authors: Fleur S
authors: http://orcid.org/0000-0003-0507-268X
authors: FS
authors: van de Bovenkamp
authors: Department of Rheumatology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands;
authors: Lise
authors: http://orcid.org/0000-0003-1622-8483
authors: L
authors: Hafkenscheid
authors: Department of Immunopathology, Sanquin Research, 1066 CX Amsterdam, the Netherlands; Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands; T.Rispens@sanquin.nl Yoann.Rombouts@gmail.com.
authors: Theo
authors: T
authors: Rispens
authors: Department of Rheumatology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands; Center for Proteomics and Metabolomics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands; and Université Lille, CNRS, UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle, F 59 000 Lille, France T.Rispens@sanquin.nl Yoann.Rombouts@gmail.com.
authors: Yoann
authors: http://orcid.org/0000-0003-4482-2199
authors: Y
authors: Rombouts
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology; D005260:Female; D006031:Glycosylation; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000737:chemistry* / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D011134:Polysaccharides / Q000276:immunology*; D011247:Pregnancy; D006023:Glycoproteins
chemical_list: D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D011134:Polysaccharides; C046179:glycosylated IgG; D006023:Glycoproteins