Monocyte chemotactic protein-1 (MCP-1) also known as monocyte chemotactic and activating factor (MCAF) was identified based on its ability to chemoattract monocytes. Subsequently, MCP-1 has also been found to regulate adhesion molecule expression and cytokine production in monocytes. MCP-1 is identical to the product of the JE gene, a PDGF inducible gene. MCP-1 is a member of the beta (C-C) chemokine subfamily, known as CCL2. The 4E2/MCP antibody reacts with mouse MCP-1. This antibody does not react with human MCP-1 and related mouse beta chemokines, TCA3 and MIP-1beta. The 4E2/MCP antibody can not neutralize the bioactivity of natural or recombinant MCP-1.