Purity >95% as determined by SDS-PAGE. Monocyte chemotactic protein 4 (MCP-4), also called CCL13, is induced by inflammatory proteins such as interleukin 1 (IL-1) and tumor necrosis factor alpha (TNFa). MCP-4 is a ligand for the G protein coupled chemokine receptors CCR2, CCR3, and CCR5. MCP-4 activates signaling in monocytes, T lymphocytes, eosinophils, and basophils during inflammation and allergic responses.