Anti-Sa antibodies: prognostic and pathogenetic significance to rheumatoid arthritis
Rheumatic Disease Research Laboratory, University of Manitoba, Winnipeg, Manitoba, Canada
Arthritis Res Ther 2004, 6:86-89 doi:10.1186/ar1171Published: 10 March 2004
Anti-Sa antibodies are detected in the serum of 20–47% of patients with rheumatoid arthritis. These antibodies have a high degree of specificity for the disease, and appear to identify a subset of early rheumatoid arthritis patients destined to have aggressive and destructive disease. It has recently been confirmed that anti-Sa antibodies are directed to citrullinated vimentin, thus placing them in the anti-citrulline family of autoantibodies. The Sa antigen has previously been shown to be present in synovium. This, along with the demonstration of citrullinated proteins in rheumatoid synovium, suggests that anti-Sa antibodies may play a pathogenetic role in the initiation and/or persistence of rheumatoid synovitis.