Augmentation of interleukin-2 production and delayed hypersensitivity in mice infected with Mycobacterium bovis and fed a diet supplemented with vitamin A acetate.

High-dose Mycobacterium bovis-infected mice fed a vitamin A acetate-supplemented diet developed a positive skin reaction to purified protein derivative of mycobacteria, and their spleen cells showed an increased IL-2 production in vitro.