Altered bone marrow reconstitution by RAG-1^−/−Sca1⁺lin⁻ cells expressing activated Notch1.

Competitive repopulation of lethally irradiated C57BL/6 Ly5.1 mice (n = 5 for each group) transplanted with 2000 RAG-1^−/−Sca1⁺lin⁻Ly5.2⁺ bone marrow cells expressing control vector (MSCV-GFP) or activated Notch1 (MSCV-ICN/GFP) along with 1.5 × 10⁵ Ly5.1⁺ competing bone marrow cells. Bone marrow cells from the animals receiving transplants were harvested 5 months after transplantation and assessed by flow cytometry using antibodies against the indicated antigens. (A) Charts show average ± SEM of the percentage of cells in the GFP⁺Ly5.2⁺ subpopulation staining with the indicated antibodies. Data were analyzed using Student ttest (Gr-1, P = .04; Mac1, P = .13; Ter119,P = .03; B220, P = .01). (B) Charts show absolute numbers ± SEM of cells staining with antibodies to the indicated antigens and normalized to the absolute number of GFP⁺Ly5.2⁺Sca1⁺lin⁻cells. Data are from the same animals shown in panel A. Data were analyzed using the Student t test (Gr-1,P = .02; Mac1, P = .01; Ter119,P = .01; B220, P = .001).