IFNG and infection: These early gene profiling studies in infected human macrophages provided evidence for the importance of IFN-γ transcription in suppressing Mtb gene expression [17], highlighted a prominent role for IL-1β and other proinflammatory cytokines at early and late timepoints after infection, and showed that macrophage responses to pathogenic mycobacteria differed from responses to infection with nonpathogenic mycobacteria [18–22].