AGBL3 and synovitis: At the 1 and 2 year follow-up, 18.9% and 34.2%, respectively, of individuals with dual CCP2/CCP3 positivity developed subclinical synovitis on longitudinal scans compared with 6.4% and 10.1% of CCP2+ individuals with negative anti-CCP3 antibodies (P < 0.01 for both) (Fig. 2a).