To examine the role of miR-155 in chemokine production in vitro, we replicated the high expression levels of miR-155 in synovial CD14+ by transfecting blood CD14+ monocytes of HCs and RA patients with a functional miR-155 mimic (miR-155m) or CM and assessed the levels of chemokine production and mRNA expression by multiplex ELISA (14 chemokines; n = 15 healthy, n = 16 RA) and TaqMan low-density array (22 chemokines; n = 8 for both HCs and RA) assays, respectively. This evidence concerns the gene CD14 and rheumatoid arthritis.