CXCL6, also known as LIX in mice, is a CXC chemokine that signals through the CXCR2 receptor. It is expressed in monocytes, platelets, endothelial cells, and mast cells. LIX is a chemoattractant for neutrophils. The two naturally occurring variants of LIX, LIX 1-78 (GCP-2) and LIX 9-78 (GCP-2), contain 78 and 70 amino acid residues, respectively. LIX contains the four conserved cysteine residues present in CXC chemokines, and also contains the 'ELR' motif common to CXC chemokines that binds to the CXCR1 and CXCR2 receptors. Recombinant Murine LIX is a 7.6 kDa protein consisting of amino acid residues 9-78 of the full length LIX protein (70 amino acids).