Forced expression of STAT3-C enhances the output of Sca-1⁺lin^– bone marrow cells in vitro. Purified lin^– bone marrow cells were transduced with MIG or Stat3-C and the cells were then maintained for an additional 48 hours under the same conditions (but without virus). The proportion of lin^–Sca-1⁺ cells within the transduced (GFP⁺) population was then measured. (A) Representative FACS plots. (B) Mean percent ± SEM of results from 3 experiments. **P <.01.