Table 1. Toxicity of bone marrow progenitor cells (in vitro).
| Conc. (ng ml−1) | Wild type | Mrp1 KO | Mdr1ab DKO | Mdr1ab/Mrp1 TKO |
|---|---|---|---|---|
| 100 | − | − | − | − |
| 50 | + | − | − | − |
| 25 | + | − | + | − |
| 10 | + | ± | + | − |
| 5 | ND | + | ND | − |
| 2 | ND | + | ND | ± |
| 1 | ND | + | ND | + |
Bone marrow cells harvested from wild-type, Mrp1 KO, Mdr1ab DKO and Mdr1ab/Mrp1 (TKO) mice were incubated continuously with various concentrations of vincristine. Colonies were scored by day 5. Wells were scored with − when the number of colonies was reduced by more than 90% relative to control wells without the drug (IC90). ± indicates a borderline value, whereas clearly less than 90% reduction is marked by a + sign. ND means not determined.