IL-1β is involved in up-regulating hepcidin expression in HuH7 cells.
A, supernatants of control, B. longum-, and B. fragilis-infected THP-1 cells were analyzed for the presence of IL-1β by ELISA. *, p = 0.0001; **, p = 0.005; n = 5–9 samples/group from multiple experiments. B, supernatants of control, B. longum-, and B. fragilis-infected THP-1 cells were analyzed for the presence of IL-6 by ELISA. *, p = 0.008; n = 9–12 samples/group from multiple experiments. C, HuH7 cells were treated for 4 h with the supernatant of B. longum-infected THP-1 cells (−) or with the supernatant in the presence of 5 μg/ml of either a neutralizing anti-IL-1β antibody or an irrelevant isotype-matched control antibody. Hepcidin expression was measured by quantitative RT-PCR. *, p = 0.008; **, p = 0.04; ***, p = 0.008; n = 3 samples/group from one of two similar experiments. Con, control. D, HuH7 cells were treated for 4 h with the supernatant of B. fragilis-infected THP-1 cells (−) or with the supernatant in the presence of 5 μg/ml of either a neutralizing anti-IL-1β antibody or an irrelevant isotype-matched control antibody. Hepcidin expression was measured by quantitative RT-PCR. *, p = 0.003; **, p = 0.01; ***, p = 0.01; n = 3 samples/group from one of two similar experiments.