CCL15 is a human chemokine which acts predominantly on chemokine receptor CCR1 and to a lesser degree on CCR3. It is a potent chemoattractant for monocytes and lymphocytes in vitro and, after i.p. application, CCL15 induces recruitment neutrophils, monocytes, and lymphocytes into mouse peritoneum. CCL15 is constitutively expressed in the gut and in the liver and was identified to circulate in human plasma. The N-terminus of CCL15 was found to be important to exert its full biological activity. HCC-2 shares significant sequence homology with CKb8 and the murine chemokines C10, CCF18/MRP-2, and macrophage inflammatory protein 1g, which all contain six instead of four conserved cysteines.