Response to cytokine combinations that induce cell differentiation. CD34⁺/CD99^low (□) and CD34⁺/CD99^high (▪) cells were induced to differentiate in different culture conditions. Specific markers were analyzed for each differentiation assay. Results are expressed as the percentage of positive cells for each marker (top panels) and as the absolute number of cells expressing these markers (bottom panels). Analyses were performed at 12 days of culture for erythroid conditions (A), 15 days for dendritic conditions (B), and 5 weeks for NK (C) and B-cell differentiation (D). Data are mean ± SEM of 6 experiments for each differentiation assay. ^*P < .05.