Effects of hepcidin challenge on the expression of ferroportin mutation variants. Western blots of THP-1 cells transfected with ferroportin/c-Myc expression vector (lanes 1, 4, and 7), A77D ferroportin mutant/c-Myc expression vector (lanes 2, 5, and 8), and N144H ferroportin mutant/c-Myc expression vector (lanes 3, 6, and 9). Cells were either left untreated (lanes 1–3), treated with LPS (1 μg/mL) for 6 hours (lanes 4–6) or exposed to native human hepcidin (1 μg/mL) for 3 hours (lanes 7–9). Monocytes were subjected to protein extract preparation and subsequent Western blotting for quantification of c-Myc protein expression. Western blotting for β-actin was used as an internal control. One of 3 representative experiments is shown.