UT7 MPL S204P cells are less cytokine-dependent than UT7 MPL WT. (A) Growth of UT7 MPLS204P and UT7 MPLWT at limiting dilution without cytokines. Cells (20 per well) were cultured without cytokines in a 96-well plate. Colony growth was counted 1 week later. (B) Rescue experiments by GM-CSF. Cells (20 per well) were cultured without cytokines in a 96-well plate. After 3 days, GM-CSF (5 ng/mL) was added and colonies were counted 1 week later. (C) Rescue experiments by TPO. Cells (20 per well) were cultured without cytokines in a 96-well plate. After 3 days, TPO (10 ng/mL) was added and colonies were counted 1 week later. Results represent the means ± SD of the number of colonies/96-well plate. Each point corresponds to the number of clone in 1 plate.