Taken together, our results demonstrate that even though T2D involves reduction of some components of a Th1 response and increase of IL-4, vaccination with BCG reduced TB pathology via T CD4+ lymphocytes, production of IFN-γ, and TNF-α, being more effective than BCGΔBCG1419c against pneumonia during acute TB. This evidence concerns the gene IL4 and type 2 diabetes mellitus.