CXCR3 (C-X-C chemokine receptor type 3) is a G protein-coupled,seven-transmembrane domain chemokine receptor that is expressed on the surface of a number of cell types,including activated CD4+ and CD8+ T cells,NK and NK-T cells,plasmacytoid dendritic cells,and some B cells . CXCR3 binds and is activated by the three IFN-gamma-inducible chemokines: CXCL9,CXCL10,and CXCL11. Binding of these ligands to CXCR3 has been implicated in regulating T-cell infiltration during inflammation and tissue injury . Alternatively spliced transcript variants encoding different isoforms have been found for this gene. One of the isoforms,CXCR3B,mediates the angiostatic activity of CXCR3 ligands and also acts as functional receptor for CXCL4 . This monoclonal antibody is specific to CXCR3B.