beta 2-Glycoprotein I reactivity of monoclonal anticardiolipin antibodies from patients with the antiphospholipid syndrome

Arthritis Rheum. 1994 Oct;37(10):1453-61. doi: 10.1002/art.1780371008.


Objective: To elucidate the specificity of anticardiolipin antibodies (aCL) from patients with the antiphospholipid syndrome (APS) to various phospholipids (PLs), DNA, and beta 2-glycoprotein I (beta 2-GPI).

Methods: Five monoclonal aCL were established from peripheral blood lymphocytes of 3 patients with the APS. The reactivity of monoclonal aCL with various PLs, with DNA, and with beta 2-GPI was examined by enzyme-linked immunosorbent assay (ELISA).

Results: All of the monoclonal aCL bound to anionic PLs, only in the presence of beta 2-GPI. Neither monoclonal aCL nor beta 2-GPI bound to DNA. Monoclonal aCL bound to solid-phase beta 2-GPI on polystyrene ELISA plates that had carboxyl groups on their surface, but did not react with solid-phase beta 2-GPI on ordinary polystyrene plates. A mixture of beta 2-GPI and CL inhibited the binding of monoclonal aCL to beta 2-GPI, but CL or beta 2-GPI alone did not.

Conclusion: Monoclonal aCL may recognize a cryptic epitope, which appears as a result of beta 2-GPI binding to anionic PLs or to polystyrene with carboxyl groups.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibodies, Anticardiolipin / drug effects
  • Antibodies, Anticardiolipin / immunology*
  • Antibodies, Monoclonal / drug effects
  • Antibodies, Monoclonal / immunology*
  • Antibody Specificity*
  • Antiphospholipid Syndrome / immunology*
  • DNA / immunology
  • Female
  • Glycoproteins / immunology
  • Glycoproteins / pharmacology*
  • Humans
  • Phospholipids / immunology
  • beta 2-Glycoprotein I


  • Antibodies, Anticardiolipin
  • Antibodies, Monoclonal
  • Glycoproteins
  • Phospholipids
  • beta 2-Glycoprotein I
  • DNA