Notch progressively depletes LT-HSC activity and numbers over time in nontransplanted Rosa26-Flox-STOP-Flox-Notch-GFP mice. Mx-cre^tgRosa26-Flox-STOP-Flox-YFP control mice (“YFP control”) and Mx-cre^tgRosa26-Flox-STOP-Flox-ICN-GFP (“Notch”) mice were injected with pI-pC to activate YFP control and ICN-GFP, respectively in HSCs. (A) BM DP T-cell production (CD4⁺CD8⁺) by the HSC compartment was measured at 4 and 16 weeks after injection in YFP control and Notch mice. (B) Scatter plot analysis of BM DP T-cell production by YFP control and Notch mice at 4 and 16 weeks after injection. (C) The LT-HSC compartment (Lineage⁻Sca-1⁺c-Kit⁺CD150⁺CD48⁻) was measured for the donor-derived cells (YFP⁺ or GFP⁺) in YFP control and Notch mice at 4 and 16 weeks after injection. (D) Scatter plot analysis of donor-derived (YFP⁺ or GFP⁺) LT-HSCs (Lineage⁻Sca-1⁺c-Kit⁺CD150⁺CD48⁻) in YFP control and Notch mice at 4 and 16 weeks after injection. One experiment was performed; 3 mice per condition at 4 weeks and 5 mice per condition at 6 weeks.