The CXCR3 ligands CXCL9, CXCL10, and CXCL11 are potent chemotactic factors for activated T cells [112], which are highly susceptible to infection in vivo [113], and these IFN-γ-inducible chemokines are consistently increased in expression in multiple tissues following SIV infection [47, 49, 52, 80]. This evidence concerns the gene CXCL11 and infection.