Differences in the leukemogenic activity of cultured BCR-ABL–transduced +/+ and IL-3^−/− cells.

(A) Survival curves of NOD/SCID (open symbols) and NOD/SCID-β2m^−/− (solid symbols) mice injected with 5 × 10⁶ cells from expanded clones of BCR-ABL–transduced +/+ (circles) and IL-3^−/− (squares) cells. (B) WBC counts of the blood from mice injected with BCR-ABL–transduced IL-3^−/− and +/+ cells. Controls were normal NOD/SCID-β2m^−/− and NOD/SCID mice. (C) FACS profiles of GFP⁺ bone marrow cells isolated from a representative moribund NOD/SCID mouse with leukemia, killed 60 days after injection of cells from a BCR-ABL⁺ +/+ culture and showing expression by the GFP⁺ cells of Gr-1, Mac-1, B220, CD4/CD8, Ter119, Sca-1, and c-kit. (D) Spleen weight of untreated mice or mice injected with BCR-ABL–transduced IL-3^−/− (top) or +/+ (bottom) cells.