RRR-alpha-tocopheryl succinate induced interleukin-2 production by avian splenic T lymphocytes and murine EL-4 thymic lymphoma cells.

Abstract

RRR-alpha-tocopheryl succinate (vitamin E succinate) was studied for its effects on interleukin-2 (IL-2) production by chicken splenic derived T lymphocytes and murine EL-4 thymic lymphoma cells. Supernatants from 0.1 microgram/mL vitamin E succinate-supplemented chicken splenic T cell cultures exhibited 42-72% enhanced IL-2 production over vehicle controls when tested in a chicken T cell blast bioassay. Supplementation of chicken splenic T lymphocyte cultures with butylated hydroxyanisole (BHT) and butylated hydroxytoluene (BHA) also induced elevated levels of IL-2, suggesting a role for antioxidants in IL-2 production by avian splenic T lymphocytes. Supernatants from vitamin E succinate-supplemented murine EL-4 cells (0.1 microgram/mL vitamin E succinate) induced 52-75% increased levels of IL-2 when compared to supernatants from vehicle controls when tested using a murine, IL-2-dependent CTLL-2 bioassay. IL-2 production by EL-4 cells was not enhanced by treatments with BHT, BHA, or Trolox, suggesting that vitamin E succinate-induced IL-2 production by EL-4 cells may involve a mechanism other than antioxidant effects. Vitamin E succinate plus suboptimal levels of the protein kinase C (PKC) activator phorbol myristate acetate (PMA) induced the highest levels of IL-2 by EL-4 cells. The studies provide evidence that vitamin E succinate can directly potentiate either the production or release of IL-2 from avian splenocytes and murine EL-4 cells.