CPI203 and quisinostat support ex vivo expansion of HSCs. (A) Schematic experimental design. CD34⁺ cells were enriched from cord blood and cultured in a cytokine-supplemented medium with quisinostat (0.5 nM) or CPI203 (150 nM) for 4 days. (B) Representative gating strategy of expanded HSCs (CD34⁺CD38^–CD90⁺CD45RA^–CD201⁺) and MPPs (CD34⁺CD38^–CD90^–CD45RA^–) in the indicated culture conditions. (C) The graph indicates the frequency of HSC and MPP after 4 days of culture in the indicated culture conditions (n = 9; mean ± standard deviation [SD]). (D) HSC and MPP count after 4 days of culture in the indicated culture conditions (n = 9; mean ± SD). (E) Stacked bar plot showing the composition of HSPCs expanded with only cytokines and in the presence of quisinostat and CPI203. (F) Frequency of cell cycle stages in the expanded HSCs (n = 3; mean ± SD). Statistical significance was determined by a 2-way analysis of variance (ANOVA) test for multiple comparisons: ∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. CMP, common myeloid progenitor; GMP, granulocyte monocyte progenitor.