Chemokines

Synonyms

Chemotactic cytokines; Small secreted cytokines

Definition

Chemokines are a group of small molecular weight (7–12 kDa) cytokines with chemotactic properties that signal through the seven-transmembrane receptors coupled to G_i-proteins (Oppenheim et al. 1991; Sallusto et al. 2000; Rossi and Zlotnik 2000). Although the first chemokines were originally identified and characterized based on their biological activity, many members of this family have been recently identified through the application of bioinformatics and expressed sequence tag (EST) databases (Sallusto et al. 2000). It is now recognized that the chemokine superfamily consists of a large number of ligands (approximately 48) and their receptors (Zlotnik and Yoshie 2012). Chemokines have been classified into four subfamilies based on the motif displayed by the first two cysteine residues located near their N-terminal end: CC-, CXC-, C-, and CX₃C chemokines (Rossi and Zlotnik 2000; Zlotnik and Yoshie 2012). The CXC...