THE CHEMOKINES COMPRISE a large protein family that can be divided into subfamilies on the basis of structural motifs. The common property of chemokines is leukocyte chemotaxis. Until recently, chemokines have been named randomly, with no clear system being used. Some have been included with the interleukins (eg, IL-8), and others have been given names describing a function, for example, macrophage chemotactic proteins. Others have been named according to the cell type that produces the chemokine, for example, platelet factor 4, whereas others have been named arbitrarily. In some cases, the names that have been chosen are cumbersome to use, which has resulted in these chemokines being almost always referenced by an abbreviated form of the name, for example, RANTES. Many chemokines show overlapping functions, and this has caused some confusion in identifying the molecules associated with particular experimental observations. Chemokines mediate their biologic effects via interactions with a large family of 7-transmembrane G protein-coupled receptors. Although each receptor subtype typically binds multiple chemokines, the specificity is restricted by chemokine subfamily. This has led to a logical receptor nomenclature system in which each receptor is designated by chemokine subfamily name (C, CC, CXC, CX3C) followed by the letter “R” designating “receptor” and a number, based on the chronologic order in which it was identified. This system has been in place since 1996 and has been officially endorsed by the Nomenclature Committee of the International Union of Pharmacology (Pharmacol. Rev. 52, 145–176 [2000]). In some cases, CD numbers have been assigned to particular chemokine receptors, and the block CD181–CD199 has been reserved for future use for such receptors (see Table).

In an attempt to clarify, if not solve, the now confused and complex nomenclature associated with chemokines, Drs. Yoshie and Zlotnik have devised a systematic nomenclature paralleling that of the receptor nomenclature system recently published (Immunity 12, 121–127 [2000]). The Chemokine Nomenclature Subcommittee of the Nomenclature Committee of the International Union of Immunological Societies has considered this system and recommended its adoption by IUIS/WHO. The system is outlined in the Table. Those scientists wishing to maintain a linkage with the historical nomenclature are recommended to quote this in brackets after the systematic name. The Table is an updated version of the system.