In contrast, no differences were found betweenESX-1-proficient and ΔESX-1 Mtb strains when IL-1βsecretion was studied (S4 Fig.), which is consistent with theinflammasome/caspase-1-independent IL-1β secretion in mice duringMtb infection [46] and which is different to the situation in humans [36]. This evidence concerns the gene CASP1 and infection.