Matriptase-2 links erythropoietin to iron

In this issue of Blood,Nai et al demonstrate that the serine protease matriptase-2 mediates erythropoietin (EPO)-dependent suppression of hepcidin, a central regulator of iron homeostasis with causal or contributing roles in iron-loading diseases, hemoglobinopathies, and infectious, inflammatory, and neoplastic disorders.1