title: The role of monocytes in the suppression of PHA-induced proliferation and IL 2 production of human mononuclear cells by 1,25-dihydroxyvitamin D3.
abstract: 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] inhibited phytohemagglutinin (PHA)-induced proliferation of human blood mononuclear cells (MNC) at concentrations of 10(-11) M or more. Interleukin 2 (IL 2) production of T cells activated with PHA was also inhibited by 1,25(OH)2D3. Furthermore, 1,25(OH)2D3 suppressed interleukin 1 (IL 1) production of monocytes (Mo), and the agent-treated Mo were unable to promote IL 2 production of non-adherent cells (NAC). Thus, the reduction of proliferative response of MNC to PHA by 1,25(OH)2D3 appeared to have resulted from the inhibitory effects of the agent on both IL 2 and IL 1 production. From these data, 1,25(OH)2D3 appears to play an important role in the immunoregulatory system.
mesh_terms: D002117:Calcitriol / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis*; D007700:Kinetics; D009000:Monocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D010835:Phytohemagglutinins / Q000494:pharmacology*
chemical_list: D007376:Interleukin-2; D010835:Phytohemagglutinins; D002117:Calcitriol