CX3CR1

CX3C chemokine family (δ-chemokines) has the two N-terminal cysteine residues separated by three variable amino acids in the conserved position. This family contains only one ligand, called CX3CL1, also known as fractalkine or neurotactin, which is unique in possessing a mucin-like glycosylated stalk that allows it to exist as a soluble or membrane-bound chemokine. CX3CR1 is a 7-transmembrane receptor for CX3CL1 and mediates both its adhesive and migratory functions. In addition, it is shown that CX3CL1 and CX3CR1 are involved in the pathogenesis of various clinical disease states, such as atherosclerosis, glomerulonephritis, cardiac allograft rejection, and rheumatoid arthritis.