Due to the elevated expression of MCP-1 after 2fLI treatment of PAR2+ monocytes/macrophages, we used flow cytometry to determine the expression of the receptor for MCP-1, CCR2, in monocyte/macrophage subsets and in SF cells of PsA patients and compare its expression to patients with OA and RA (n=10 each). This evidence concerns the gene CCL2 and rheumatoid arthritis.