Figure 5. β-catenin is required for the increase in HSCs/HPCs induced by Gsk3-rnai.

(A) BM cells were harvested from Mx-Cre;β-catenin^fl/fl mice with or without injection of polyI:polyC for 14 days, transduced with control or Gsk3-rnai carrying lentivirus, and transplanted into lethally irradiated recipient mice. After 4 months, percentage and absolute number of HSC-containing LSK fraction were compared among the 4 groups. (B) BM cells were harvested at 4 months from primary recipients of WT and Mx-Cre;β-catenin^fl/fl mice transduced with vector control or Gsk3-rnai lentivirus (from primary recipient mice in A) and transplanted into lethally irradiated secondary hosts. After 4 months, percentage and absolute number of HSC-containing LSK fraction were compared among the 4 groups. (C) Summary of serial transplantation data in WT versus β-catenin CKO mice. Shown is fold change in GFP⁺ LSK cells in recipients of Gsk3-depleted BM normalized to vector control, for otherwise WT primary, secondary, and tertiary recipients as well as for primary and secondary β-catenin CKO recipients. Survival in tertiary recipients of Gsk3/β-catenin–deficient BM was too low for statistical significance. *P < 0.05.