title: Antibodies to anionic phospholipids and anti-beta2-GPI: association with thrombosis and thrombocytopenia in systemic lupus erythematosus.
abstract: In this study, we evaluated the prevalence and association with thrombosis and/or thrombocytopenia of IgG and IgM antibodies to cardiolipin (aCL), phosphatidic acid (aPA), phosphatidylinositol (aPI), phosphatidylserine, and beta(2)-glycoprotein I (abeta(2)-GPI) in systemic lupus erythematosus (SLE). Sera were obtained from 87 patients affected by SLE (77 of the 87 patients were females), 41 of them with a history of arterial and/or venous thrombosis. Antiphospholipid antibodies and abeta(2)-GPI were evaluated by enzyme-linked immunosorbent assay. IgG-aCL, IgG-aPA, IgG-aPI, IgG-aPS, and IgG-abeta(2)-GPI were found in 53%, 37%, 32%, 38%, and 24% of patients, respectively. IgM-aCL, IgM-aPA, IgM-aPI, IgM-aPS, and IgM-abeta(2)-GPI were detected in 15%, 17%, 18%, 14%, and 16%, respectively. With respect to antibody titer, IgG-aCL strongly correlated with all other antiphospholipid antibodies and abeta(2)-GPI of IgG isotype. Thrombosis was significantly associated with IgG-aPA (p = 0.044), IgG-aPI (p = 0.038), IgG-aPS (p = 0.026), IgG-abeta(2)-GPI, IgM-aPA (p = 0.044), IgM-aPI (p = 0.024), and IgM-aPS (p = 0.01), irrespective of antibody titer, whereas IgG-aCL were associated with thrombosis and thrombocytopenia when taken at medium-high titer (p = 0.009 and p = 0.046, respectively). Our results confirm that, besides aCL and abeta(2)-GPI, other antibodies to negatively-charged phospholipids are present in a large percentage of patients with SLE. However, it remains doubtful whether these other antiphospolipid antibodies actually represent an important parameter predictive of thrombosis and thrombocytopenia in SLE.
authors.affiliation: Department of Clinical Medicine, University La Sapienza, Rome, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Amoroso
authors.forename: Anna P
authors.initials: AP
authors.lastname: Mitterhofer
authors.forename: Flavia
authors.initials: F
authors.lastname: Del Porto
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Garzia
authors.forename: Gianni M
authors.initials: GM
authors.lastname: Ferri
authors.forename: Sara
authors.initials: S
authors.lastname: Galluzzo
authors.forename: Marta
authors.initials: M
authors.lastname: Vadacca
authors.forename: Domenico
authors.initials: D
authors.lastname: Caccavo
authors.forename: Antonella
authors.initials: A
authors.lastname: Afeltra
mesh_terms: D000293:Adolescent; D000328:Adult; D017152:Antibodies, Antiphospholipid / Q000276:immunology; D001323:Autoantibodies / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology*; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000276:immunology*; D013921:Thrombocytopenia / Q000209:etiology / Q000276:immunology*; D019851:Thrombophilia / Q000209:etiology / Q000276:immunology; D013927:Thrombosis / Q000209:etiology / Q000276:immunology*; D053482:beta 2-Glycoprotein I
chemical_list: D017152:Antibodies, Antiphospholipid; D001323:Autoantibodies; D001324:Autoantigens; D006023:Glycoproteins; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M; D010743:Phospholipids; D053482:beta 2-Glycoprotein I