Fig. 2.

Pretreatment of murine and human HSPCs with treprostinil and forskolin does neither induce apoptosis nor alters cell cycle progression or differentiation potential. Human HSPCs were incubated with 10 μM treprostinil and 30 μM forskolin for 1h. Subsequently, (A, B) apoptosis induction and (C, D) cell cycle progression was assessed by flow cytometric analysis. Representative original pictures are depicted (A, C, left hand panel) and data obtained in three independent experiments was summarized (B, D, right hand panel). No difference in apoptotic cells or distribution of cells according to G_0/1, S and G₂ phase was detected between untreated and treated cells (one way ANOVA). (E, F) Murine HSPCs were isolated form bone marrow, pretreated and resuspended in a methylcellulose medium containing growth factors required for supporting the differentiation and growth of granulo-monocytic colony–forming units (CFU-GM) and of the erythrocyte lineage (BFU-E, burst-forming-unit erythroid). After 10 days the number of colonies was counted under a light microscope and shape and morphology of colonies was observed. Shown are representative photomicrographs and the quantification of three independent experiments. Data are means ± S.E.M. (n = 3).