[Physiology of eryhtropoietin and its therapeutic use]

Erythropoietin (Epo) is a glycoprotein produced primarily by the kidney and is the factor regulating the red blood cell production. Unlike most of the hematopoietic growth factors, Epo is principally produced by a single organ, the kidney, and is regulated by a classic feedback control system. Epo acts on the erythroid progenitors after binding to a specific receptor. The gene coding for a 66 Kd chain has been cloned. This chain belongs to the hematopoietic growth factors family. Epo gene was cloned in 1985. The protein coded by this gene is heavily glycosylated. Epo production is regulated by renal tissue hypoxia. Cells producing Epo in the kidney are a subset of peritubular interstitial cells of fibroblastic origin. Epo is now used in clinical applications. Rationale for the use of Epo is based on the serum determination of Epo level. Patients with anemia of chronic renal failure are routinely treated with recombinant Epo. Two other indications are recognized by French authorities: the treatment of anemia of cancer patients receiving platin-derived chemotherapy and the use in autologous blood donation.