CXCR3 and infection: Moreover, colonic expression of Cxcr3, a chemokine receptor that is preferentially expressed on Th1 cells and promotes their recruitment to sites of inflammation [42], [43], was significantly increased (∼3 fold) in day 3-infected mice (Fig. 6D); however, expression of this critical chemokine receptor was significantly down-modulated by day 5 of infection, highlighting the change in the inflammatory status of the gut upon GI anthrax progression.