AGBL2 and rheumatoid arthritis: When applying a similar cut-off, as was used for IgG anti-CCP2, >2SD above the mean of HCs, 83 UC patients (37%) and 52 CD patients (32%) were seropositive for IgA anti-CCP2, while only 1 (2.8%) HC and 64 (74%) RA patients were.