SELENIUM AND VITAMIN-E-DEFICIENCY IMPAIR TRANSFERRIN RECEPTOR INTERNALIZATION BUT NOT IL-2, IL-2 RECEPTOR, OR TRANSFERRIN RECEPTOR EXPRESSION

Vitamin E and Se deficiency increase the risk of disease by impairing the immune response, To aid in the understanding of how vitamin E and Se deficiency reduce immmune competence, this study examined several m echanisms necessary for lymphocyte proliferation, Weanling rats were f ed a vitamin E-deficient, selenium-deficient, or control diet for 8 we eks. At this time splenic mononuclear cells were isolated and stimulat ed with concanavalin A for 48 h, Although the percentage of lymphocyte s and monocytes capable of proliferating were consistent among the die tary groups, lymphocyte proliferation was decreased significantly in v itamin E-and selenium-deficient rats, This decrease in proliferation T vas not associated with alterations in interleukin-2, interleukin-2 re ceptor, or transferrin receptor expression, However, stimulated cells from vitamin E- and Se-deficient rats internalized few if any transfer rin receptors, Reduced transferrin receptor internalization may Limit lymphocyte expansion by depleting the intracellular iron stores needed for cellular function and proliferation.