http://www.creativebiomart.net/description_382663_12.htm

Chemokines are a family of structurally related leukocyte chemoattractant cytokines that play a central role during immunoregulatory and inflammation processes. All chemokines contain four conserved cysteines linked by disulfide bonds, and two major subfamilies, namely CXC and CC, are defined on the basis of the first two cysteines which are separated by one amino acid or are adjacent. Human CCL1, also well known as I-309, is a small glycoprotein (73 amino acid residue as mature form) secreted by activated T lymphocytes. Human I-309 is assumed to be homologous to the mouse TCA-3 despite of the only approximately 42% amino acid sequence identity. CCL1 interacts with the G protein-linked transmembrane chemokine receptors CCR8, and induces biochemical events that may result in the control of chemotaxis, proliferation, apoptosis and adhesion. It has been demonstrated that CCL1 displays chemotactic activity for monocytes and other cell types such as NK cells and dendritic cells, but not for neutrophils. Furthermore, as the only known physiological ligand for CCR8, CCL1 was identified as a potent inhibitor of HIV-1 envelope-mediated cell-cell fusion and virus infection.