title: Antibodies to beta2-glycoprotein I--a specific marker for the antiphospholipid syndrome.
abstract: The antiphospholipid syndrome is a disorder characterized by recurrent thrombosis and the presence of antibodies specific to phospholipids. However, the diagnosis of this syndrome is hampered by the lack of a specific laboratory test. In this study an ELISA for the measurement of antibodies to solid-phase beta2-glycoprotein I (beta2-GPI) was established and compared with anticardiolipin antibodies for diagnosis of antiphospholipid syndrome. Significantly elevated levels of antibodies to beta2-GPI were found in all patients with definite antiphospholipid syndrome (median = 91 AU). Marginally elevated levels of antibodies to beta2-GPI were observed in 5% of patients with systemic lupus erythematosus (SLE; median = 4 AU), 1% with stroke (median = 3 AU), 13% with infectious mononucleosis (median = 3 AU), 10% with HIV infection (median = 3 AU) and 8% with VDRL false-positive serology for syphilis (median = 4 AU), but not in patients with rheumatoid factor, syphilis or carotid artery stenosis. In contrast, significantly raised levels of anticardiolipin antibodies were observed in 100% of patients with definite antiphospholipid syndrome, 30% with SLE, 88% with HIV infection, 94% with syphilis, 62% with infectious mononucleosis, 9% with rheumatoid factor-positive sera, 74% VDRL false-positive serology for syphilis, 47% with stroke and 0% with carotid artery stenosis. This solid-phase assay for antibodies to beta2-GPI is highly specific for the antiphospholipid syndrome and represents an advance in the laboratory diagnosis of this disorder.
authors.affiliation: Department of Immunology, St James' Hospital, Dublin, Ireland.
authors.forename: J
authors.initials: J
authors.lastname: Guerin
authors.forename: C
authors.initials: C
authors.lastname: Feighery
authors.forename: R B
authors.initials: RB
authors.lastname: Sim
authors.forename: J
authors.initials: J
authors.lastname: Jackson
mesh_terms: D017153:Antibodies, Anticardiolipin / Q000032:analysis; D016736:Antiphospholipid Syndrome / Q000175:diagnosis*; D001323:Autoantibodies / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D002561:Cerebrovascular Disorders / Q000175:diagnosis; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005189:False Positive Reactions; D006023:Glycoproteins / Q000276:immunology*; D015658:HIV Infections / Q000175:diagnosis; D006801:Humans; D007244:Infectious Mononucleosis / Q000175:diagnosis; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis; D008562:Membrane Glycoproteins / Q000276:immunology*; D013587:Syphilis / Q000175:diagnosis; D053482:beta 2-Glycoprotein I
chemical_list: D017153:Antibodies, Anticardiolipin; D001323:Autoantibodies; D015415:Biomarkers; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053482:beta 2-Glycoprotein I