title: beta-Sitosterol and beta-sitosterol glucoside stimulate human peripheral blood lymphocyte proliferation: implications for their use as an immunomodulatory vitamin combination.
abstract: The phytosterols, beta-sitosterol (BSS), and its glucoside (BSSG) enhance the in vitro proliferative response of T-cells stimulated by sub-optimal concentrations of phytohaemagglutinin (PHA) several fold at extremely low concentrations (femtogram level). A 100:1 (mass:mass) ratio of BSS:BSSG (termed essential sterolin formulation, ESF) showed higher stimulation than the individual sterols at the same concentration. In 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 baseline values. In vitro, ESF (1 microgram.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 EST a higher activity was always found at different effector:target ratios (100:1 12:1).
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Stellenbosch, Tygerberg, South Africa.
authors.forename: P J
authors.initials: PJ
authors.lastname: Bouic
authors.forename: S
authors.initials: S
authors.lastname: Etsebeth
authors.forename: R W
authors.initials: RW
authors.lastname: Liebenberg
authors.forename: C F
authors.initials: CF
authors.lastname: Albrecht
authors.forename: K
authors.initials: K
authors.lastname: Pegel
authors.forename: P P
authors.initials: PP
authors.lastname: Van Jaarsveld
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000328:Adult; D000970:Antineoplastic Agents / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D004338:Drug Combinations; D005260:Female; D006684:HLA-DR Antigens / Q000502:physiology; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000502:physiology; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D012855:Sitosterols / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
chemical_list: D000276:Adjuvants, Immunologic; D000970:Antineoplastic Agents; D004338:Drug Combinations; D006684:HLA-DR Antigens; D007376:Interleukin-2; D012855:Sitosterols; D007371:Interferon-gamma; C011015:lyoniside