CXCs
Chemokines are divided into 2 major subfamilies, CXCL s and CCLs, based on the arrangement of the first 2 of the 4 conserved cysteine residues; the 2 cysteines are separated by a single amino acid in CXCLs chemokines and are adjacent in CCLs chemokines.
CXCLs chemokines are further subdivided into ELR and non-ELR types based on the presence or absence of a glu-leu-arg sequence adjacent and N terminal to the CXC motif. ELR types are chemotactic for neutrophils, while non-ELR types are chemotactic for lymphocytes.
See also:
chemokines (CCLs and CXCLs)