title: Circadian rhythmicity of interferon-gamma production in antigen-stimulated whole blood.
abstract: Recently, assessment of T cell function has been refined by the ability to measure cytokines produced by activated T cells. We developed a whole blood assay to detect antigen-activated T cells that produce IFN-gamma. With this assay we have found a large circadian variation in tetanus- (acrophase 00(00) p < 0.001) and PPD- (acrophase 00(08) p < 0.001) stimulated IFN-gamma production. IFN-gamma production is inversely correlated with plasma cortisol (r = -0.5), suggesting that variation in IFN-gamma production may be secondary to circadian variation in plasma cortisol levels (acrophase 11(06)). The demonstration of circadian rhythmicity in antigen-stimulated IFN-gamma production is relevant to the diagnostic use of whole blood assays and, in addition, may have implications for the therapy of immuno-inflammatory diseases.
authors.affiliation: Burnet Clinical Research Unit, Walter and Eliza Hall Institute, Royal Melbourne Hospital, Parkville, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Petrovsky
authors.forename: P
authors.initials: P
authors.lastname: McNair
authors.forename: L C
authors.initials: LC
authors.lastname: Harrison
mesh_terms: D000941:Antigens / Q000008:administration & dosage; D002940:Circadian Rhythm / Q000276:immunology* / Q000502:physiology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007371:Interferon-gamma / Q000097:blood*; D018655:Lymphocyte Count; D008297:Male; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000276:immunology; D014373:Tuberculin / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000941:Antigens; D013745:Tetanus Toxoid; D014373:Tuberculin; D007371:Interferon-gamma; D006854:Hydrocortisone