CCL14 is a homeostatic chemokine present at high concentrations in normal human plasma. CCL14 shares 46% sequence identity with CCL3 and CCL4, and it is a weak CCR1 agonist. The NH2- terminus of CCL14 can be cleaved by urokinase plasminogen activator and/or plasmin, and the resulting CCL14 (9-74) chemokine becomes a strong agonist for CCR1, CCR5, and a weak agonist for CCR3. Subsequently, CCL14 (9-74) is a substrate for dipeptidyl peptidase (CD26) that removes two amino acids to produce CCL14 (11-74), which is inactive. CCL15 and CCL23 similarly have an extended N-terminal domain that is cleaved, which activates them. CCL14, in conjuction with CX3CL1 and CCL4, promotes trophoblast migration at the feto-maternal interface. In addition, it has been published that modifying CCL14, eliminating amino acids 1-8 and substituting amino acid in position 9 by nonanoic acid, led to the identification of a potent CCR3 agonist, n-nonanoyl (NNY)-CCL14 (10-74). NNY-CCL14 induces release of reactive oxygen species and leads to chemotaxis of human eosinophils. Also, it acts as an agonistic inactivator of CCR1, CCR2, CCR3, and CCR5. CCL14 is constitutively expressed in different tissues, and its concentration in plasma increases up to 10-fold in inflammatory conditions and in chronic renal failure.