Epidemiological and clinical data of patient and control populations*.

*Age, Hb, Hct, WBC, and Plt counts are expressed as median (range). Diagnosis was made according to WHO criteria (see text for details). Values reported in the table are those at the moment in which blood was drawn for experiments. PMF and ET patients were at diagnosis or before the beginning of any cytoreductive therapy. Patients with PV were all under treatment with phlebotomy (but not with cytostatic therapy) in order to try to lower their Hct below 45% (males) or 42% (females). Healthy CTRLs hematological values were assessed before treatment with G-CSF (see text for details).