title: 1,25-Dihydroxyvitamin D3 inhibits secretion of interferon-gamma by mitogen- and antigen-stimulated bovine mononuclear leukocytes.
abstract: 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the biologically active metabolite of vitamin D, and delta 22-26-F3-1,25-dihydroxyvitamin D3 (delta 22-26-F3-1,25(OH)2D3), a synthetic analog with a high affinity for the vitamin D receptor, significantly inhibited interferon-gamma (IFN-gamma) secretion in 24- and 48-h cultures of pokeweed mitogen (PWM) and ovalbumin (OVA) stimulated peripheral blood mononuclear leukocyte (MNL) from adult, OVA-sensitized dairy cattle. Vitamin D-induced inhibition of IFN-gamma production was most pronounced in MNL cultures supplemented with 1,25(OH)2D3 at 1.0 nM or more, a concentration equal to or exceeding that in plasma of cows with clinical hypocalcemia. Secreted IFN-gamma was undetectable in all resting MNL cultures. Ultra-low concentrations (0.0001, 0.001, and 0.01 nM) of 1,25(OH)2D3 had no effect on IFN-gamma secretion by PWM-stimulated bovine MNL, unlike a previous study in other species demonstrating enhancement of IFN-gamma secretion at these concentrations. Preincubation of MNL with.
authors.affiliation: US Department of Agriculture, Agricultural Research Service, Ames, IA 50010-0070, USA.
authors.forename: B N
authors.initials: BN
authors.lastname: Ametaj
authors.forename: D C
authors.initials: DC
authors.lastname: Beitz
authors.forename: T A
authors.initials: TA
authors.lastname: Reinhardt
authors.forename: B J
authors.initials: BJ
authors.lastname: Nonnecke
mesh_terms: D000818:Animals; D000941:Antigens / Q000494:pharmacology*; D002117:Calcitriol / Q000031:analogs & derivatives / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D005260:Female; D007371:Interferon-gamma / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D010047:Ovalbumin / Q000494:pharmacology; D011043:Pokeweed Mitogens / Q000494:pharmacology*; D014807:Vitamin D / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D000941:Antigens; D011043:Pokeweed Mitogens; D014807:Vitamin D; D007371:Interferon-gamma; D010047:Ovalbumin; D002117:Calcitriol