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 immune competence, this study examined several mechanisms necessary for lymphocyte proliferation. Weanling rats were fed a vitamin E‐deficient, selenium‐deficient, or control diet for 8 weeks. At this time splenic mononuclear cells were isolated and stimulated with concanavalin A for 48 h. Although the percentage of lymphocytes and monocytes capable of proliferating were consistent among the dietary groups, lymphocyte proliferation was decreased significantly in vitamin E‐ and selenium‐deficient rats. This decrease in proliferation was not associated with alterations in interleukin‐2, interleukin‐2 receptor, or transferrin receptor expression. However, stimulated cells from vitamin E‐ and Sedeficient rats internalized few if any transferrin receptors. Reduced transferrin receptor internalization may limit lymphocyte expansion by depleting the intracellular iron stores needed for cellular function and proliferation. J. Leukoc. Biol. 63: 131–137; 1998.