BETA-SITOSTEROL AND BETA-SITOSTEROL GLUCOSIDE STIMULATE HUMAN PERIPHERAL-BLOOD LYMPHOCYTE-PROLIFERATION - IMPLICATIONS FOR THEIR USE AS AN IMMUNOMODULATORY VITAMIN COMBINATION

The phytosterols, beta-sitosterol (BSS), and its glucoside (BSSG) enha nce the in vitro proliferative response of T-cells stimulated by sub-o ptimal concentrations of phytohaemagglutinin (PHA) several fold at ext remely low concentrations (femtogram level). A 100:1 (mass:mass) ratio of BSS:BSSG (termed essential sterolin formulation, ESF) showed highe r stimulation than the individual sterols at the same concentration. I n vivo activity of ESF was also demonstrated when volunteers ingested ESF for 4 weeks. Proliferation of their T-cells, stimulated maximally with PHA, was significantly enhanced (20-920%) when compared to baseli ne values. In vitro, ESF (1 mu g/ml) was able to significantly enhance the expression of CD25 and HLA-Dr activation antigens on T-cells and increased the secretion, into the medium, of IL-2 and gamma interferon . NK-cell activity was also increased by BSS and BSSG alone, but with ESF a higher activity was always found at different effector:target ra tios (100:1-12:1). (C) 1997 International Society for Immunopharmacolo gy.