The effects of protein deprivation on cell-mediated immunity

The effect of protein insufficiency on immune responsiveness was investigated in inbred mice fed isocaloric diets low and normal in protein. Mice were tested for aberrations of cell-mediated and humoral immunities. Protein insufficiency enhances cell-mediated immunity while depressing or not affecting humoral immunity. Cell-mediated immunity was enhanced in testing: allogeneic skin graft rejection, spleen cell responsiveness to phytohemagglutinin, the graft-vs-host reaction, macrophage function, and resistance to viral and bacterial infections.