The chemokines are a family of proinflammatory cytokines that act through cell surface receptors to regulate numerous cellular processes. Chemokines exert their effects through G protein-coupled receptors (GPCRs) which are relatively non-selective in their ligand binding. As a result of this promiscuity, many chemokine receptors bind more than one chemokine with high affinity. Chemokines are classified into four subfamilies according to the pattern of conserved cysteines in their amino acid sequences. They include CC chemokines, CXC chemokines, C chemokines and CX3C chemokines...