In the last few years, it has become evident that citrullination is not the only post-translational modification (PTM) recognized by autoantibodies in RA patients, as anti-carbamylated protein antibodies (anti-CarP), anti-acetylated protein antibodies (AAPA), and anti-malondialdehyde-acetaldehyde antibodies (anti-MAA) were discovered in the serum of RA patients [8–10]. Here, NAA10 is linked to rheumatoid arthritis.