Editorial: Thrombopoietin

Thrombopoietin.

By Shirley Ebbe I T HAS BEEN CLEAR for almost 20 years that platelet production is subject to homeostatic regulatory mechanisms that result in stimulation when the platelet count is li w’ and suppression when it is high.2 In spite of elapsed time, the physiologic processes that are involved in those regulatory mechanisms are not clear. Thrombocytopoiesis may be regulated by a humoral thrombopoi...

The biology of thrombopoietin and thrombopoietin receptor agonists.

Thrombopoietin (TPO) is the major physiological regulator of platelet production. TPO binds the TPO receptor, activates JAK and STAT pathways, thus stimulating megakaryocyte growth and platelet production. There is no "sensor" of the platelet count; rather TPO is produced in the liver at a constant rate and cleared by TPO receptors on platelets. TPO levels are inversely proportional to the rate...

Clinical indications for thrombopoietin and thrombopoietin-receptor agonists.

Thrombocytopenia is a common hematologic disorder. Stimulation of thrombopoiesis may reduce the risk for thrombocytopenia-induced bleeding, prevent severe thrombocytopenia, and reduce the need for platelet transfusion. The key cytokine is thrombopoietin (TPO). It regulates proliferation and maturation of megakaryocytes as well as platelet production. TPO is synthesized in the liver. Development...

Defining units for thrombopoietin.

Thrombopoietin in Regulation