AGALACTOSYL GLYCOFORMS OF IGG AUTOANTIBODIES ARE PATHOGENIC

The glycosylation of IgG results in many different glycoforms. A large body of correlative data (including remission of arthritis during pre gnancy) has suggested that IgG molecules lacking galactose were associ ated with rheumatoid arthritis. We now demonstrate that agalactosyl Ig G glycoforms are directly associated with pathogenicity in murine coll agen-induced arthritis. We show that passive transfer of an acute syno vitis in T-cell-primed mice can be enhanced by using IgG containing au toantibodies to type II collagen when the antibodies are present as th e agalactosyl glycoform. Thus, nonpathogenic doses of autoantibodies t an be made pathogenic by altering their glycosylation state.