1,25-Dihydroxyvitamin D3 regulates proliferation of activated T-lymphocyte subsets.
The biologically active vitamin D metabolite, 1,25-(OH) 2D3 suppressed phytohaemagglutinin (PHA)-induced lymphocyte proliferation dose-dependently (0.1 nM-100 nM), and decreased the OKT4+/OKT8+ ratio and transferrin-receptor-positive (OKT9+) cells. A possible parallelism between expression of 1,25-(OH) 2D3 receptors and interleukin 2 (IL2)-receptors recognized by anti-Tac antibody was not confirmed in this study. However, the addition of exogenous IL2 abolished the inhibitory effects of 1,25-(OH) 2D3 on PHA-stimulated T-cell proliferation, and the decrease of OKT4+ and OKT9+ T-cell in this population. Among various vitamin D3 analogues examined, 1,25-(OH) 2D3 was the most potent anti-proliferative effect, followed in order by 1,24S-(OH) 2D3, 1 alpha OH D3, 25 OH D3 and 24,25-(OH) 2D3.
Matsui
T
T
Nakao
Y
Y
Koizumi
T
T
Nakagawa
T
T
Fujita
T
T
D000954:Antigens, Surface / Q000032:analysis; D002117:Calcitriol / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002762:Cholecalciferol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D013601:T-Lymphocytes / Q000145:classification / Q000187:drug effects*
D000954:Antigens, Surface; D007376:Interleukin-2; D002762:Cholecalciferol; D002117:Calcitriol