Detection of ‘antiphospholipid’ antibodies: a single chromogenic assay of thrombin generation sensitively detects lupus anticoagulants, anticardiolipin antibodies, plus antibodies binding β2‐glycoprotein I and prothrombin

• Published in: Clinical and experimental immunology 2001-06, Vol.124 (3), p.502-508
• Main Authors: Sheng, Y., Hanly, J. G., Reddel, S. W., Kouts, S., Guerin, J., Koike, T., Ichikawa, K., Sturgess, A., Krilis, S. A.
• Format: Article
• Language: English
• Subjects: antiphospholipid syndrome; autoimmunity; Biological and medical sciences; Blood coagulation; General aspects; Immunity to Infection; Immunopathology; Investigative techniques, diagnostic techniques (general aspects); lupus anticoagulant; Medical sciences; thrombin generation; β2‐glycoprotein I
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1046/j.1365-2249.2001.01555.x

The diagnosis of the antiphospholipid syndrome (APS) requires both a typical clinical event plus a persistently positive test in an assay for either anticardiolipin (aCL) antibodies or a lupus anticoagulant (LA). Enzyme linked immunosorbent assays (ELISA) specific for autoantibodies against β2‐glycoprotein I (β2GPI) or prothrombin are also used, but none of the tests are adequately sensitive or specific. A chromogenic assay was developed that measures the effect of test antibody or plasma samples on in vitro thrombin formation. It is able to detect both LA and β2GPI‐dependent aCL antibodies and may have greater specificity for APS than currently available tests. Using this method various monoclonal antibodies (MoAbs) were examined, from mice immunized with β2GPI, mice with a spontaneous animal model of APS, and from three humans with APS. Plasma and affinity purified antibodies from patients with APS and control groups were also examined. Thrombin inhibition was more sensitive to perturbation by MoAbs than a combination of tests for LA (P