MEC is a secreted CC chemokine expressed primarily by epithelial cells of the bronchioles, salivary gland, mammary gland and colon. MEC signals through the CCR10 receptor and chemoattracts resting CD4, CD8 T-cells and eosinophils. MEC contains six cysteines including the four highly conserved cysteine residues present in CC chemokines. Recombinant murine MEC is a 12.6 kDa protein containing 111 amino acid residues.