SUPPLEMENTATION WITH SELENIUM AND HUMAN IMMUNE CELL FUNCTIONS .1. EFFECT ON LYMPHOCYTE-PROLIFERATION AND INTERLEUKIN-2 RECEPTOR EXPRESSION

Selenium (Se) is an essential nutritional factor that was shown by us to alter the expression of the high affinity interleukin 2 receptor (I l(2)-R) and its subunits, cell proliferation, and clonal expansion of cytotoxic T-lymphocytes in mice. This study shows that dietary supplem entation of Se-replete humans with 200 mu g/d of sodium selenite for 8 wk, or in vitro supplementation with 1 x 10(-7) M Se (as sodium selen ite), result in a significant augmentation of the ability of periphera l blood lymphocytes to respond to stimulation with 1 mu g/mL of phytoh emagglutinin or alloantigen (mixed lymphocyte reaction) and to express high affinity Il(2)-R on their surface. There was a clear correlation between supplementation with Se and enhanced H-3-thymidine incorporat ion into nuclear DNA, preceded by enhanced expression of high affinity Il(2)-R. Supplementation with Se can apparently modulate T-lymphocyte mediated immune responses in humans that depend on signals generated by the interaction of interleukin 2 with Il(2)-R.