CCL2 and rheumatoid arthritis: CCL2 (or monocyte chemotactic protein-1 (MCP-1)) is a major chemoattractant for monocytes, macrophages, memory T lymphocytes, and endothelial cells [10–12] and directly contributes to the pathogenesis of inflammatory diseases such as atherosclerosis, rheumatoid arthritis and diabetic nephropathy [13, 14].