Colony-forming unit granulocyte erythrocyte monocyte

Erythropoiesis is a process that starts with a pluripotent stem cell in the bone marrow that eventually differentiates into an erythroid colony-forming unit (CFU-E)4 (Fig. 63-1). The development of these cells depends on stimulation from the appropriate growth factors, primarily erythropoietin. Other cytokines involved include granulocyte-monocyte colony-stimulating factor (GM-CSF) and interleukin 3 (IL-3). Eventually, the CFU-Es differentiate into reticulocytes and cross from the bone marrow into the peripheral blood. Finally, these reticulocytes mature into erythrocytes after 1 to 2 days in the bloodstream. Throughout this process, the cells gradually accumulate more hemoglobin and lose their nuclei.4... 

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