Blood cell formation, hematopoiesis.
The production of blood cells. These include erythrocytes (hemoglobin-containing red blood cells) granulocytes, platelets, and mononuclear cells. Hematopoiesis is influenced by diet (adequate supplies of iron, copper, zinc, B vitamins), hormones and growth factors (erythropoietin, granulocyte macrophage stimulating factor, granulocyte colony-stimulating factor, and macrophage-stimulating factor), and cytokines (interleukins 1-13, stem cell factor, leukemia inhibitory factor, tumor necrosis factor, interferon). These factors direct and control the division and maturation of each of the different blood cell types.
The process of production of blood cells and platelets, which continues throughout life, replacing aged cells (which are removed from the circulation). In healthy adults, hemopoiesis is confined to the ‘bone marrow, but in embryonic life and in early infancy, as well as in certain diseases, it may occur in other sites (extramedullary hemopoiesis).