Infection drove marked alterations in chemokine transcription including a downregulation of the CCR2 ligands Ccl2 and Ccl7 and the IFNγ inducible CXCR3 ligands Cxcl9 and Cxcl10. Since CCL2 and CCL7 regulate monocyte recruitment and T-cell activation and CXCL9 and CXCL10 the recruitment of CXCR3+ T-cells during mycobacterial infection7–11,54–56, our results suggest that bystander monocyte populations may play a more important role in these processes compared to their infected counterparts. This evidence concerns the gene IFNG and infection.