Analysis of human CD34+ cell from BM grown in liquid cultures with media favoring erythroid differentiation. (A) Experimental setup. CD34+ cells were isolated by cell sorting from BM cells of PV patients (n = 3) or a pool of white blood cells from 32 healthy blood donors, deposited into 48 well plates, and cultured in presence of CB-839 or vehicle for 2 weeks. (B) Example of colonies grown from PV patient P490 after 2 weeks. (C) Percentages of cell counts relative to the vehicle (veh) group (n = 12 wells) for each patient sample and a sample from healthy controls are shown. Right panel shows the mean growth inhibition by CB-839 of the 3 patient samples and the healthy control relative to vehicle set as 100%. Mean ± SEM is represented. 2-way ANOVA with multiple comparison to DMSO with Fisher LSD test was performed in panel C. ∗P < .05, ∗∗P < .01, ∗∗∗P < .001, and ∗∗∗∗P < .0001.