I. Depressed immunological function in zinc-deprived rats as measured by mitogen response of spleen, thymus, and peripheral blood.

The in vitro responses of splenic, thymic, and peripheral blood lymphocytes to two T-cell mitogens (phytohemagglutinin and concanavalin A) and one B-cell mitogen (pokeweed mitogen) were investigated in zinc-deprived and pair-fed control rats. The responses to phytohemagglutinin of splenic, thymic, and peripheral blood lymphocytes from zinc-deprived animals were depressed by at least 50% in comparison with those of controls, and the difference between the two groups was significant for each tissue (P = 0.05). The responses to concanavalin A of splenic and peripheral blood lymphocytes were suppressed in zinc-deprived animals, and splenic and thymic responses to pokeweed mitogen were depressed by about 50% in comparison with those of controls; these results were significant at the P = 0.05 level. This study is the first to evaluate the effects of diet-induced zinc deprivation on lymphocyte transformation and immune function in rats.