CXCR6 and vitiligo: In patients with vitiligo, the overexpression of chemokine receptors of the CXC family has been reported, namely CXCR3 and CXCR6, as well as the chemokines CXCL9, 10, and 11, natural ligands of CXCR3, and CXCL16, the only known natural ligand of CXCR6 [11,19].