IFNG and infection: At 21 days Mtb post-infection, when Mtb-specific IFN-γ-producing T cells already existed in the lung (Supplementary Fig. 3i), LCMV Arm coinfection had no detrimental effect on TB pathogenesis, while only mice infected with LCMV Arm at 14 days after Mtb infection showed exacerbated gross pathology (Supplementary Fig. 3j) and more severe granuloma lesions in the lung, with necrosis characteristics and a high bacterial burden (Supplementary Fig. 3k, l).