Does the anti-prothrombin antibodies measurement provide additional information in patients with thrombosis?

• Published in: Immunobiology (1979) 2007-01, Vol.212 (7), p.557-565
• Main Authors: Bardin, Nathalie, Alessi, Marie Christine, Dignat-George, Francoise, Vague, Irene Juhan, Sampol, Jose, Harlé, Jean Robert, Sanmarco, Marielle
• Format: Article
• Language: English
• Subjects: Adult; Advanced Basic Science; Allergy and Immunology; Anti-prothrombin antibodies; Antibodies, Anticardiolipin - blood; Antibodies, Anticardiolipin - immunology; Antibodies, Antiphospholipid - blood; Antibodies, Antiphospholipid - immunology; Antibody Affinity; Antiphospholipid antibodies; Autoantibodies - blood; Autoantibodies - immunology; Autoimmune Diseases - immunology; Autoimmune Diseases - metabolism; beta 2-Glycoprotein I - immunology; Enzyme-Linked Immunosorbent Assay; Female; Humans; IgG-a β2GPI; IgG-aPS/PT; IgG-aPT; Lupus Coagulation Inhibitor - blood; Lupus Coagulation Inhibitor - immunology; Male; Middle Aged; Phosphatidylserines - immunology; Prothrombin - immunology; Thrombosis; Thrombosis - immunology
• ISSN: 0171-2985; 1878-3279
• DOI: 10.1016/j.imbio.2007.02.001

Abstract The aim of this study is to get new insight into the relevance of IgG anti-prothrombin antibodies in patients with thrombosis and to determine whether human prothrombin alone (aPT) or complexed to phosphatidylserine (aPS/PT) should be preferentially used for measuring these antibodies by enzyme-linked immunosorbent assay (ELISA). To this end, prevalence of anti-prothrombin antibodies, their characteristics in terms of avidity and heterogeneity, and their relationship with anti- β 2 glycoprotein I antibodies (a β2 GPI) were studied in 152 patients with thrombosis. Patients were divided into two groups according to the presence or absence of antiphospholipid antibodies (aPL), called aPL+ or aPL−, respectively. In the aPL− group ( n =90), the prevalence of anti-prothrombin antibodies was substantial (10%) but not significantly different from that of control (5%). In the aPL+ group ( n =62), lupus anticoagulant (LA) or anticardiolipin antibodies (aCL) positive, 61% were positive for anti-prothrombin antibodies with no statistical difference between aPT and aPS/PT prevalence (42% vs. 55%, respectively). In the whole thrombotic population, 19% were only aPT and 34% only aPS/PT suggesting the presence of different antibodies. Absorption experiments confirmed the heterogeneity of aPT and aPS/PT. No difference in their avidity was demonstrated. From the aPL+ group, 60 were LA positive. Among them, 18% were negative for a β2 GPI and anti-prothrombin antibodies showing that the detection of these antibodies could not substitute for LA determination. In conclusion, our data show that the screening of the different anti-prothrombin antibodies is not warranted in the aPL+ group since these antibodies do not provide additional information compared to aCL, LA and/or a β 2GPI measurement. Nevertheless, the substantial prevalence of anti-prothrombin antibodies in the aPL− group should be further explored in a large prospective study.