CCL2 and rheumatoid arthritis: Specifically, CCR1 (major ligands CCL3/MIP-1α, CCL5/RANTES and CCL7/MCP-3), CCR2 (major ligand CCL2/MCP-1), CCR5 (ligands CCL3/MIP-1α, CCL5/RANTES and CCL7/MCP-3) are abundantly expressed by RA monocytes/macrophages [1], [10] suggesting that interference with the migration of these cells by cytokine receptor blockade might be a successful therapeutic approach to reduce synovial inflammation.