MPL and idiopathic aplastic anemia: In addition to this, the trombopoietin receptor—the myeloproliferative leukemia (c-mpl)—is expressed both in human megakaryocytes and in human HSCs [43], and the c-mpl agonist, eltrombopag, expands the human HSPC population [45] and restores trilineage hematopoiesis in some patients with aplastic anemia [46].