Transient inhibition of PKB does not alter the colony-forming capacity of hematopoietic progenitors. CD34⁺ cells were cultured in the absence or presence of the PKB inhibitor VIII for 24 and 48 hours, on which (A) cells were stained with Hoechst33342 to determine the percentage of dividing cells (n = 4). (B) Data were depicted as the percentage of cells in S/G₂/M phase. (C) In addition, the number of cells in culture was depicted as the fold induction compared with controls in a box plot (n = 12). (D) The percentage of Lin⁻ cells, Lin⁻CD34⁺CD38⁺ cells, and Lin⁻CD34⁺CD38⁻ cells was determined by flow cytometric analysis. (E) Data were depicted as fold induction compared with untreated cells (n = 3). (F-G) CD34⁺ cells were cultured in the absence or presence of the PKB inhibitor VIII for 24 and 48 hours on which the cells were plated into methylcellulose. Colony formation was analyzed after another 12 days of culture. The total number of colonies was scored. Data were depicted as (F) the percentage of cells developed into colonies (n = 7) and (G) the percentage of granulocyte macrophage colony-forming unit (CFU-GM) and erythroid colony-forming unit (CFU-E). Error bars represent SEM. Samples significantly different (P < .05) are indicated with horizontal lines and asterisks.