Protein levels of iron-related genes in the liver and the spleen of hepcidin-deficient mice. Western blot analysis of ferroportin (on 80 μg crude membrane preparation), and of ceruloplasmin and L-ferritin (on 20 μg cytosolic preparation) from the liver (A) and the spleen (C) of Usf2^-/- and Usf2^+/- mice. Molecular weight markers are indicated on the left. Immunohistochemistry using antimouse ferroportin antibody on the liver (B) and on the spleen (D) of Usf2^-/- and Usf2^+/- mice. Original magnification, ×20 (top row, panel B), ×60 (bottom, and ×4, panel D). Kupffer cell (black arrow) and hepatocyte (black arrowheads) staining are pointed. RP and WP indicate red pulp and white pulp, respectively.