Introduction
This series includes a revision of articles on erythropoiesis and EPO gene regulation, microRNAs and their potential contribution to the development of new therapeutic strategies, animal models for studying kidney disease-associated anemia as well as benefits/risks of ESA therapy. The biological effects of new ESA molecules, heparin-binding erythropoietin and of pHBSP, and the potential applications of ESA, are also elicited in this series.