Figure 4.

Alternative Strategy for Cre-Mediated Excision Using Ex Vivo Treatment with Tat-Cre Recombinase

(A) Schematic outline of the in vitro Cre-recombination alternative strategy using Tat-Cre recombinase.

(B) TdTomato^LSL HSCs were treated with Tat-Cre in vitro. Representative fluorescence-activated cell sorting (FACS) plots of TdTomato expression in cells after 3 days in culture are shown.

(C) Col1a1-tetO-MLL/ENL x KRAS^LSL−G12D HSCs were induced in vitro with Tat-Cre to promote the activation of KRAS^G12D. Kaplan-Meier curves depict the survival of mice transplanted with Tat-Cre-induced (n = 6) or uninduced (n = 7) HSCs, under continuous MLL-ENL activation with doxycycline-containing food. ^∗∗∗p < 0.001.

(D) YFP expression in BM and spleen of transplanted mice with YFP^LSL LSK cells, Tat-Cre or sham treated, 15 days after transplantation (donor mice, n = 3; transplanted mice, n = 5).

(E) Representative FACS plots of YFP expression in donor BM cells.

(F) YFP expression in LSK and cKIT+ cells in the transplanted mice shown in (D).

Plots show means ± SEM.