Detection of IgG anti-Domain I beta2 Glycoprotein I antibodies by chemiluminescence immunoassay in primary antiphospholipid syndrome

• Published in: Clinica chimica acta Vol. 446; pp. 201 - 205
• Main Authors: Meneghel, Lauro, Ruffatti, Amelia, Gavasso, Sabrina, Tonello, Marta, Mattia, Elena, Spiezia, Luca, Tormene, Daniela, Hoxha, Ariela, Fedrigo, Marny, Simioni, Paolo
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.06.2015
• Subjects: Adult; Aged; Anti-Domain I antibodies; Anti-β2 Glycoprotein I antibodies; Antibodies, Anticardiolipin - blood; Anticardiolipin antibodies; Antiphospholipid syndrome; Antiphospholipid Syndrome - blood; Antiphospholipid Syndrome - diagnosis; Antiphospholipid Syndrome - immunology; Antiphospholipid Syndrome - pathology; beta 2-Glycoprotein I - antagonists & inhibitors; beta 2-Glycoprotein I - blood; beta 2-Glycoprotein I - immunology; Case-Control Studies; Chemiluminescence immunoassay; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoassay - methods; Immunoglobulin G - blood; Luminescent Measurements; Male; Middle Aged; Pregnancy; Pregnancy Complications - blood; Pregnancy Complications - diagnosis; Pregnancy Complications - immunology; Pregnancy Complications - pathology; Protein Structure, Tertiary; Sensitivity and Specificity; Thrombosis - blood; Thrombosis - diagnosis; Thrombosis - immunology; Thrombosis - pathology; APS; DI; Anti-β2 Glycoprotein I antibodies; aCL; PAPS; Anti-Domain I antibodies; CU; anti-β2GPI; anti-DI; Anticardiolipin antibodies; LA; Chemiluminescence immunoassay; aPL; CLIA; RLUs; ELISA; Antiphospholipid syndrome
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/j.cca.2015.04.033

IgG anti-Domain I (anti-DI) β2 Glycoprotein I (β2GPI) antibodies are associated to thrombotic risk in antiphospholipid syndrome (APS), but their detection is technically difficult. In this study, a chemiluminescent immunoassay (CLIA) was used to evaluate the clinical significance of IgG anti-DI in a large cohort of patients with primary APS (PAPS). The study population included 88 patients with PAPS, 63 ELISA-negative subjects and 166 controls. IgG anti-DI, IgG anticardiolipin (aCL) and IgG anti-β2GPI antibodies were assayed using CLIA (HemosIL AcuStar®). The sensitivity and specificity of IgG anti-DI antibodies were comparable to those of IgG aCL and IgG anti-β2GPI antibodies. There was a significant agreement, association and titre correlation between IgG anti-DI and IgG aCL as well as IgG anti-β2GPI antibodies (p<0.001 for all). IgG anti-DI antibody showed lesser prevalence and mean titres in the pregnancy morbidity than in thrombotic and PAPS patients with both involvements (p<0.001). Regarding the conventional aPL antibody profiles, the triple positivity group had higher prevalence and mean titres than single and double positivity ones (p<0.001). This study provides further evidence that anti-DI antibodies can be considered a promising biomarker for risk assessment particularly in patients having vascular thrombosis and triple conventional aPL positivity. •A chemiluminescent immunoassay was used to detect IgG anti-DI antibodies.•IgG anti-DI had a significant agreement, association with IgG aCL and IgG anti-β2GPI.•IgG anti-DI had a significant titre correlation with IgG aCL and IgG anti-β2GPI.•IgG anti-DI was associated to thrombosis and to triple positivity group in PAPS.