The effect of IL-6, IL-1α, IL-1β, IL-10 (20 ng/ml), IFN-β (250 units/ml), and cognate antibodies against these cytokines on the expression of hepcidin by primary murine hepatocytes. The target hepatocytes were derived from CB57Bl6, IL-6–/–, hfe–/–, and tfr2-mutant mice, as indicated. Each symbol represents one experiment in which two to four samples of primary murine hepatocytes were incubated with culture medium (control) or with the cytokine and antibody combination indicated.