Anti-beta2 glycoprotein I (beta2GPI) autoantibodies recognize an epitope on the first domain of beta2GPI.

ABSTRACT: Anticardiolipin (aCL) autoantibodies are associated with thrombosis, recurrent fetal loss, and thrombocytopenia. Only aCL found in autoimmune disease require the participation of the phospholipid binding plasma protein beta2 glycoprotein I (beta2GPI) for antibody binding and now are called anti-beta2GPI. The antigenic specificity of aCL affinity purified from 11 patients with high titers was evaluated in an effort to better understand the pathophysiology associated with aCL. Seven different recombinant domain-deleted mutants of human beta2GPI, and full length human beta2GPI (wild-type), were used in competition assays to inhibit the autoantibodies from binding to immobilized wild-type beta2GPI. Only those domain-deleted mutants that contained domain 1 inhibited the binding to immobilized wild-type beta2GPI from all of the patients. The domain-deleted mutants that contained domain 1 inhibited all aCL in a similar but not identical pattern, suggesting that these aCL recognize a similar, but distinguishable, epitope(s) present on domain 1.

SUBMITTER: Iverson GM 

PROVIDER: S-EPMC28079 | biostudies-literature | 1998 Dec

REPOSITORIES: biostudies-literature