title: Association of autoantibodies against the phosphatidylserine-prothrombin complex with manifestations of the antiphospholipid syndrome and with the presence of lupus anticoagulant.
abstract: OBJECTIVE
  To clarify the association of autoantibodies against prothrombin with the clinical manifestations of the antiphospholipid syndrome (APS) and with the presence of lupus anticoagulant (LAC).
  
  
  METHODS
  We examined 265 patients who visited our autoimmune disease clinic. IgG and IgM antiprothrombin antibodies were tested by enzyme-linked immunosorbent assay (ELISA) as either antiphosphatidylserine-prothrombin complex (aPS/PT) antibodies or as antibodies against prothrombin coated on irradiated ELISA plates (as antigen) (aPT). IgG, IgM, and IgA anticardiolipin (aCL) antibodies and their beta2-glycoprotein I (beta2GPI) dependency were also evaluated by ELISA. LAC was tested by 3 different methods.
  
  
  RESULTS
  The presence of aPS/PT, but not of aPT, significantly correlated with the clinical manifestations of APS (odds ratio [OR] 4.39, 95% confidence interval [95% CI] 2.06-9.38), and aPS/PT antibodies were as specific as beta2GPI-dependent aCL for APS (93.1% for both). IgG aPS/PT strongly correlated with the presence of LAC as detected using the dilute Russell viper venom time test (OR 38.2, 95% CI 13.4-109.1).
  
  
  CONCLUSIONS
  Antiprothrombin antibodies are heterogeneous and their clinical relevance depends on the method of detection applied. Positive results on the aPS/PT test can serve as a marker of thrombotic events in patients with autoimmune diseases.
authors.affiliation: Hokkaido University School of Medicine, Sapporo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Atsumi
authors.forename: M
authors.initials: M
authors.lastname: Ieko
authors.forename: M L
authors.initials: ML
authors.lastname: Bertolaccini
authors.forename: K
authors.initials: K
authors.lastname: Ichikawa
authors.forename: A
authors.initials: A
authors.lastname: Tsutsumi
authors.forename: E
authors.initials: E
authors.lastname: Matsuura
authors.forename: T
authors.initials: T
authors.lastname: Koike
mesh_terms: D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D017153:Antibodies, Anticardiolipin / Q000097:blood; D000925:Anticoagulants / Q000097:blood; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000097:blood; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D016682:Lupus Coagulation Inhibitor / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010718:Phosphatidylserines / Q000276:immunology*; D011516:Prothrombin / Q000276:immunology*; D053482:beta 2-Glycoprotein I
chemical_list: D017153:Antibodies, Anticardiolipin; D000925:Anticoagulants; D001323:Autoantibodies; D006023:Glycoproteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D016682:Lupus Coagulation Inhibitor; D010718:Phosphatidylserines; D053482:beta 2-Glycoprotein I; D011516:Prothrombin