Measurement of anti-phospholipid antibodies by ELISA using beta 2-glycoprotein I as an antigen

J Immunol Methods. 1991 Oct 25;143(2):223-9. doi: 10.1016/0022-1759(91)90047-j.


The requirement of plasma cofactor beta 2-glycoprotein I for binding autoantibodies against anionic phospholipids has been reported. We describe the development of an enzyme-linked immunosorbent assay (ELISA) for anti-phospholipid antibodies using highly purified beta 2-glycoprotein I for coating microtitre plates. Intra- and interassay coefficients of variation, determined with serum pools of low, medium and high positivity, ranged between 3% and 18%. 54 sera from patients with systemic lupus erythematosus and related autoimmune disorders were analyzed by this assay; the results correlated well to those obtained in an ELISA using anionic phospholipids on the solid phase (r = 0.85, P less than 0.001). The two ELISA systems showed similar sensitivities although 8/31 positive sera scored negative in the beta 2-glycoprotein I ELISA. The latter group of eight sera showed significantly higher anti-phosphatidylcholine/anti-phosphatidylserine binding ratios than the group of 23 sera which scored positive in both assays. This new assay should permit accurate measurement of most of the clinically relevant anti-phospholipid antibodies and avoid inconsistencies likely to arise from secondary interactions that characterize lipid-based ELISA.

MeSH terms

  • Amino Acid Sequence
  • Antiphospholipid Syndrome / immunology
  • Apolipoproteins / immunology*
  • Autoantibodies / analysis*
  • Cardiolipins / immunology
  • Enzyme-Linked Immunosorbent Assay*
  • Glycoproteins / immunology*
  • Humans
  • Immunoglobulin G / analysis*
  • Lupus Erythematosus, Systemic / immunology
  • Molecular Sequence Data
  • Phospholipids / immunology*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • beta 2-Glycoprotein I


  • Apolipoproteins
  • Autoantibodies
  • Cardiolipins
  • Glycoproteins
  • Immunoglobulin G
  • Phospholipids
  • beta 2-Glycoprotein I