In order to investigate the biologic processes underlying and resulting from the megakaryocytic hyperplasia that characterizes idiopathic myelofibrosis (IMF), peripheral blood CD34 ؉ cells isolated from patients with IMF, polycythemia vera (PV), and G-CSF-mobilized healthy volunteers were cultured in the presence of stem cell factor and thrombopoietin. IMF CD34 ؉ cells generated 24-fold greater numbers of megakaryocytes (MKs)

The JAK2 V617F mutation has been shown to occur in the overwhelming majority of patients with polycythemia vera (PV). To study the role of the mutation in the excessive production of differentiated hematopoietic cells in PV, CD19 ؉ , CD3 ؉ , CD34 ؉ , CD33 ؉ , and glycophorin A ؉ cells and granulocytes were isolated from the peripheral blood (

There is controversy as to whether murine definitive hematopoiesis originates from yolk sac (YS) or the intraembryonic region. This study reports the generation of definitive hematopoietic stem cells