IFNG and tuberculosis: It also indicates that even though vaccinates with detectable M. bovis had higher numbers of Tcm producing IFN-γ/TNF-α as compared to vaccinates with no M. bovis, the moderate levels of IFN-γ/TNF-α/IL-2 (or a combination of factors) would have conferred, if not a sterilizing protection, a significant decrease/delay in TB-associated pathology even in the presence of the pathogenic bacilli.