IL-27 enhances proliferation and differentiation of human CD34⁺ cells. (A) Human CD34⁺ cells (10⁴ cells/0.5 mL/well) were cultured in medium supplemented with SCF (50 ng/mL), TPO (10 ng/mL), and Flt3 ligand (20 ng/mL) and with or without IL-6 (50 ng/mL) and sIL-6Rα (50 ng/mL) in the presence of IL-27 (0.1, 1, 10, and 100 ng/mL) in triplicate. On days 5 and 9, cells were counted and stained with various combinations of antibodies and analyzed by flow cytometry. Data in the total cell number are shown as the mean (± SD). * indicates P < .05, compared with control. Numbers represent the percentage of cells in each area. A representative result obtained day 9 from 2 independent experiments was shown (B). Similar results were obtained in more than 2 independent experiments.