Figure 6.

Effects of retrovirus-mediated human MnSOD or catalase on mouse hematopoietic cells in vitro and in vivo. Sorted GFP⁺ cells isolated from MSCV-MnSOD-GFP, MSCV-catalase-GFP, or MSCV-GFP–infected BM cells were plated at 4 × 10⁴ cells/plate, and CFUs were scored at day 8. (a) Colony counts from the nonirradiated cells and (b) colony counts from cells that received 2 Gy radiation. Data are presented as means ± SEM of three independent experiments (*P < 0.05, **P < 0.01). (c) Comparison of the donor reconstitution rates in MnSOD, catalase, and mock vector-transduced HSCs following competitive transplantation into 10 Gy-irradiated recipient mice. Three months after transplantation, mice were re-treated with 2 Gy radiation and donor engraftment rates were continually monitored until 6 months after the transplantation. Chart lines represent the ratio of CD45.1⁺MnSOD⁺ or CD45.1⁺catalase⁺ cells to CD45.1⁺ mock vector control⁺ cells in the peripheral blood. Data are presented as means ± SEM of three independent transplantation experiments (n = 13–20 per group, *P < 0.05). BFU-E, burst-forming unit-erythroid; BM, bone marrow; CFU-G, colony-forming unit-granulocyte; CFU-GM, colony-forming unit-granulocyte, macrophage; CFU-M, colony-forming unit-macrophage; GFP, green fluorescent protein; MnSOD, manganese superoxide dismutase; MSCV, murine stem cell virus.