Inhibitors effect on yield and injury of in vitro–grown megakaryocytes. (A) Yield of viable day 12 CD41⁺ megakaryocytes per HPC plated with or without the addition of SU6656, Y27632, and AZD1152. Mean yield ± 1 SEM is shown for N = 6 independent experiments. P values were determined using 1-way ANOVA in comparison with the control. (B) Yield of viable day 12 CD41⁺CD42b^High megakaryocytes per HPC plated with or without the addition of SU6656, Y27632, and AZD1152 as in panel A. Mean yield ± 1 SEM is shown for N = 6 independent experiments. P values were determined using 1-way ANOVA in comparison with the control. (C) Percentage of viable CD41⁺ megakaryocytes that were also CD42b^High on day 12 of culture. (D) Percentage of Annexin V⁺ CD41⁺CD42b^High day 12 megakaryocytes was done as in panel B, but for Annexin binding to the megakaryocytes at day 12. For panels C and D, mean percentage-positive cells ± 1 SEM is shown for N ≥ 7 independent experiments. P values were determined using 1-way ANOVA in comparison with the control.