Known for its ability to chemoattract monocytes and macrophages, it will activate monocytes, upregulate cellular adhesion molecules. It is a strong pro-inflammatory chemokine that belongs to the CC chemokine subfamily.

CCL2 a product of the human JE gene. The protein is synthesized in a 99 amino acid precursor form. The Mature form is 76 amino acids long. It is readily synthesized by fibroblasts, most tumor cells, smooth muscle cells, neutrophils, and endothelial cells. MCP-1 is commonly expressed constituitively or upon activation in most transformed cells. In vivo, it is upregulated in most pro-inflammatory situations.

CCL2 (MCP-1) is a valuable addition to almost any cytokine study. If MCP-1 is expressed, the other cytokines also found elevated usaually depends on the situation. If monocyte lineages are involved, you will find IL-1a, IL-1b, IL-6, IL-10, TNFa, and RANTES (TNFa if macrophage). If it is a general pro-inflammatory reponse, you will often also see IL-1a, IL-6, IL-8, IL-10, IL-12, IFNy, MIP-1a, and RANTES.