We cloned the mouse homologue of the chemokine receptor CXCR3, which is located in mouse chromosome X. We screened a large panel of chemokines for their ability to induce a calcium flux in mouse CXCR3-transfected cells and identified a new ligand for this receptor, the recently reported CC chemokine 6Ckine. This represents an example of a CC chemokine, which binds to a CXC chemokine receptor. Like other ligands of this receptor, 6Ckine has angiostatic properties. 6Ckine is known to chemoattract T cells. In line with this, CXCR3 is expressed preferentially in Th1 cells and in lymphoid organs of the IL-10(-/-) mouse that develops chronic colitis. Its ability to attract T cells as well as its angiostatic properties suggest that 6Ckine may be an effective anti-tumor agent.