In this study, we identified a novel DC population, deriving from monocytes in the blood of both RA and PsA patients, which we characterize as ‘CD209/CD14+ DC’, expressing the classical DC markers, including HLA-DR and CD11c (29, 30), CD209 (DC-SIGN), which are used to identify Mo-DC in vitro and in vivo (23, 28, 31), while still retaining the monocytic marker CD14 (32). Here, CD209 is linked to rheumatoid arthritis.