ANTI BETA-2-GLYCOPROTEIN-I ANTIBODIES IN A PATIENT WITH CATASTROPHIC ANTIPHOSPHOLIPID SYNDROME

Autoimmune antiphospholipid antibodies are a hallmark of patients with antiphospholipid syndrome, and require a protein cofactor, beta 2-gly coprotein I, to bind anionic phospholipids. In these same patients, mo reover, IgG directly binding beta 2-glycoprotein I are described. We f ound high plasma titres of both IgM and IgG anti beta 2-glycoprotein I antibodies in a patient with catastrophic antiphospholipid syndrome. After passing plasma through a Sephacryl S-300 column, an identical di stribution pattern between anti beta 2-glycoprotein I and anticardioli pin antibodies was observed, Moreover, when IgG immunocomplexes were i solated from a high molecular fraction, IgM anti-beta 2-glycoprotein I and anticardiolipin antibodies were detected, Thus IgG, IgM ad IgG-Ig M complexes of anti-beta 2-glycoprotein I antibodies are present at th e same time in a patient with antiphospholipid syndrome.