ACR CONVERGENCE 2020—Recent research findings suggest rheumatologists need to take a closer look at two gold standard autoantibodies used to diagnose seropositive rheumatoid arthritis (RA)—rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP), according to Caroline Grönwall, PhD, and Miriam Shelef, MD, PhD, who discussed Antibodies in RA: Beyond Citrullination & Back to Rheumatoid Factor at ACR Convergence on Friday, Nov. 6, 2020.
How important is citrulline? Emerging evidence suggests that citrullinated proteins are one of several post-translational modifications targeted by cross-reactive autoantibodies in RA. This session reviewed new anti-modified protein antibodies (AMPAs) and considers: Is citrullination a special modification targeted by RA autoantibodies or simply the first to be characterized? Findings have importance for how we assess RA autoantibody repertoires and future diagnostics. Although RF and anti-CCP often co-exist, new evidence suggests unique risk factors for each, different timing in pre-clinical RA, different pathophysiologic roles, and both common and unique epitopes.