For instance, the high-throughput purification of anti-citrullinated peptide/protein antibodies (ACPA), i.e. autoantibodies specific for rheumatoid arthritis (RA), has been achieved by repeated capturing on 96-well plates coated with a synthetic circular peptide containing citrulline, called CCP2 (cyclic citrullinated peptide 2) (19, 89, 90). The gene discussed is PRTN3; the disease is rheumatoid arthritis.