Juvenile idiopathic arthritis is associated with potentially pathogenic glycosylation of IgG

Purpose The structure of human IgG includes 2 internal glycans that modulate the conformation and function of the Fc region. Adult-type rheumatoid arthritis (RA) has been associated with an elevated proportion of hypogalactosylated (G0) IgG that exhibits enhanced fixation of complement and greater pathogenicity in experimental murine arthritis. We aimed to determine the profile of IgG glycans in normal children and in those with juvenile idiopathic arthritis (JIA), for comparison with healthy adults and adult RA controls.