title: Avidity of anti-beta2-glycoprotein I and thrombosis or pregnancy loss in patients with antiphospholipid syndrome.
abstract: We aimed to evaluate avidity of anti-beta(2)-glycoprotein I antibodies (anti-beta(2)-GPIs) in patients with antiphospholipid syndrome (APS) at the time of acute thrombotic events or pregnancy loss as compared with clinical event-free periods. To do so, 69 sera samples from 16 patients (6 with primary APS and 10 with APS secondary to systemic lupus erythematosus ) were selected on the basis of anti-beta(2)-GPI positivity. Avidity of IgG anti-beta(2)-GPIs was determined by chaotropic enzyme-linked immunosorbent assay (ELISA), using increased NaCl concentration during antibody binding. High, heterogeneous, and low-avidity anti-beta(2)-GPIs were measured in APS patients, with no clear pattern regarding the time of thrombotic events or pregnancy failure. In general, anti-beta(2)-GPI avidity did not change substantially during disease course. We concluded that avidity of anti-beta(2)-GPIs appears to be a rather stable parameter in an individual APS patient. Considering the previously shown association of high-avidity anti-beta(2)-GPIs with venous thrombosis, avidity of anti-beta(2)-GPIs may be a better predictor of predisposition to thrombosis and unsuccessful pregnancy than levels of antiphospholipid antibodies, which may fluctuate over time owing to several factors.
authors.affiliation: Department of Rheumatology, University Medical Center, Vodnikova 62, SI-1000 Ljubljana, Slovenia. sasa.cucnik@guest.arnes.si
authors.forename: S
authors.initials: S
authors.lastname: Cucnik
authors.forename: B
authors.initials: B
authors.lastname: Bozic
authors.forename: T
authors.initials: T
authors.lastname: Kveder
authors.forename: M
authors.initials: M
authors.lastname: Tomsic
authors.forename: B
authors.initials: B
authors.lastname: Rozman
mesh_terms: D000022:Abortion, Spontaneous / Q000209:etiology*; D000915:Antibody Affinity / Q000276:immunology*; D016736:Antiphospholipid Syndrome / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D011247:Pregnancy; D013927:Thrombosis / Q000209:etiology*; D053482:beta 2-Glycoprotein I
chemical_list: D006023:Glycoproteins; D007074:Immunoglobulin G; D053482:beta 2-Glycoprotein I