Inhibition of T lymphocyte mitogenesis by 1,25-dihydroxyvitamin D3 (calcitriol).

摘要: Abstract Recent studies have suggested that vitamin D may other important biologic activities in addition to its well-characterized role the maintenance of calcium homeostasis. Discovery cytosolic receptors for human peripheral blood monocytes and lectin-stimulated lymphocytes prompted us study effects 1,25-dihydroxyvitamin D3 (calcitriol), most biologically active metabolite D, upon phytohemagglutinin (PHA)-induced lymphocyte blast transformation. We found calcitriol is a potent inhibitor PHA-induced proliferation, achieving 70% inhibition tritiated thymidine incorporation after 72 h culture. Furthermore, suppressed interleukin-2 (IL-2) production by PHA-stimulated mononuclear cells concentration-dependent fashion. Lastly, suppressive effect on cellular proliferation was partially reversed saturating amounts purified IL-2. conclude transformation this mediated, part, through suppression IL-2 production. Thus, appears possess immunoregulatory properties been unappreciated heretofore.