Cyclin D2 enhances short-term reconstitution in vivo. (A-B) Lethally irradiated mice (CD45.2) were transplanted with 3600 LSK (CD45.1) cells transduced with control- or cyclin D2–containing vectors, and 150 000 whole BM (CD45.2) cells. Reconstitution was analyzed in PB 3 to 4 weeks (short term) and 4 months (long term) after transplantation. (A) Total PB reconstitution by transplanted CD45.1 cells. (B) Myeloid (CD11b/Gr1⁺B220^–CD3^–) PB reconstitution by transduced (CD45.1) cells. Data in panel A are mean (SD) values from 14 (control) and 12 (cyclin D2) mice in a total of 3 experiments, and in panel B from 8 to 9 mice in 2 experiments. (C) BM cellularity 4 months after transplantation of mice that received transplants with 7000 to 10 000 control- or cyclin D2–transduced LSK cells without competitor cells. BM cells were harvested from femurs and tibias (crushed in a mortar), and nucleated cells were enumerated. Data are mean values (SD) from 3 experiments with 4 to 7 mice that received transplants in each experiment. *P < .05.