Reduction in IgG galactose in juvenile and adult onset rheumatoid arthritis measured by a lectin binding method and its relation to rheumatoid factor.

Glycosylation changes in patients with juvenile chronic and adult onset rheumatoid arthritis have been studied using a novel binding method. Both these major types of arthritis showed decreased galactosylation of serum IgG, which confirms earlier studies using a different, more complex chemical method. No significant correlation between serum IgG, IgM, and IgA rheumatoid factors and age corrected G(o) (percentage of oligosaccharide chains lacking galactose) was found. The possibility that the less glycosylated IgG is preferentially confined to circulating IgM/IgG immune complexes cannot be excluded, however.