EPO (Erythropoietin)

Erythropoietin (EPO), also known as hematopoietin or hemopoietin, is a type of hormone in humans that regulates red blood cell (erythrocyte) production, a process called erythropoiesis. EPO is primarily synthesized in the kidneys of adult humans and in the liver cells of fetuses during the natal and prenatal period. EPO targets erythroblasts, which are multipotent stem cells and erythrocyte precursors in the bone marrow, to stimulate erythropoiesis.

[Page 579]Because EPO targets erythroblasts in the bone marrow and serves to protect them from apoptosis and because erythroblasts are covered with EPO membrane receptors, erythroblasts will not differentiate into erythrocytes without the presence of EPO. White blood cell precursors known as basophilic erythroblasts also exhibit EPO membrane receptors, and therefore white cell production is also somewhat regulated by ...