Inverse correlation between apoptosis and HbF reactivation in β thalassemia. Evaluation of apoptotic cells (left panels) and HbF content (right panels) at terminal erythroid differentiation in normal, β-TI, and β-TM HPC cultures supplemented or not with KL (100 ng), alone or in combination with Dex (10⁻⁸ M). Mean (± SEM) values from 7 separate experiments on 7 different donors are reported. Variance analysis was expressed as Bonferroni P values. *P < .05, **P < .01, ***P < .001.