IFNG and tuberculosis: The induction of T cells producing IFN-γ, IL-2 and TNF (Th1 response) observed in CysVac5-vaccinated mice (Figure 2) correlates with vaccine-induced Th1-mediated protection, as numerous studies have demonstrated the correlation of these responses with protective immunity in animal models, and evidence is accumulating on the important contribution of IL-17 to anti-TB immunity [15,25,26].