PRTN3 and rheumatoid arthritis: Among the multiple factors promoting bone remodeling in RA, autoantibodies, as anti-citrullinated protein antibodies (ACPA) as well as anti-carbamylated peptide (anti-CarP) antibodies, have been associated with the development and progression of bone erosions and juxta-articular bone resorption as well as a decreased BMD (10–15).