FREQUENCY OF AUTOANTIBODIES TO A MAJOR EPITOPE ON THE CARBOXYL-TERMINAL FRAGMENT OF CENP-B IN PATIENTS WITH AUTOIMMUNE-DISEASE

The carboxyl-terminal fragment of CENP-B contains a major epitope for anti-centromere antibodies (ACA). We have developed an enzyme-linked i mmunoassay (ELISA) for measuring antibodies to the 147-carboxyl-termin al amino acids of CENP-B expressed as a beta-galactosidase fusion prot ein. The ELISA was 98% sensitive and 95% specific for detecting ACA in a population which included 46 patients with ACA detected by other me ans. Therefore, the CENP-B ELISA should prove a valuable tool in scree ning for ACA in populations at risk of developing systemic sclerosis, such as those with Raynaud's phenomenon. Levels of anti-CENP-B antibod ies were not increased in unaffected relatives of probands with ACA.