PTPN22 and rheumatoid arthritis: Serum autoantibodies against citrullinated vimentin, common in RA patients, have also been shown to promote osteoclastogenesis and bone resorption in a mouse model 36, raising the possibility that PTPN22 could regulate vimentin‐dectin‐1 driven uptake and presentation of autoantigens, in addition to cytokine secretion.