HbF reactivation in sibling BFU-E colonies.
(A) HbF reactivation in pooled sibling BFU-E colonies grown in erythroid culture in presence of graded amounts of KL. Clonogenetic parameters are shown in top panels. In the bottom part, HbF synthesis is monitored in terms of percentage of F cells and γ-chain content. Mean ± SEM values from 3 separate experiments. The correlation between cell numbers per colony and percentage values of F cells (r = 0.8, P = .0002) or HbF content (r = 0.91, P < .0001) is highly significant. (B) HbF reactivation in single sibling BFU-E colonies treated with graded amounts of KL, as evaluated in terms of F cells (% values) in each colony. Top panel, results from 8 groups of sibling colonies (mean values are shown). Bottom, direct correlation between F cell number (% values) and cell number × 103 per colony in the 32 sibling clones (see top panel).
