Molecular cloning of a major CENP-B epitope and its use for the detection of anticentromere autoantibodies.

An enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of anticentromere autoantibodies in sera of patients with suspected or manifest rheumatic diseases. The antigen source used in this assay consists of the recombinant protein of glutathione S-transferase (GST) fused to the last 60 C-terminal amino acid residues of the major centromere protein CENP-B. Although this CENP-B segment is only a small part of the complete polypeptide, we show that it constitutes an important autoimmune antigenic domain which is recognized by all patient sera in which ACA can be detected using the immunoblotting technique with a HeLa S3 nuclear protein extract as antigen source.