Monocyte chemotactic/chemo-attractant protein-1 (also known as C–C motif chemokine ligand 2, MCP-1/CCL2) is a key chemokine in the regulation of monocyte and macrophage migration and infiltration and has been associated with inflammatory diseases like atherosclerosis and rheumatoid arthritis [92]. Here, CCL2 is linked to rheumatoid arthritis.