Fig. 5.
Methotrexate resistance of mice transplanted with varying amounts of line 04 DHFR transgenic marrow cells.
Normal male mice were given 1 Gy TBI the day before transplantation with 1 × 106, 5 × 106, or 1 × 107 marrow cells from female line 04 donors (as indicated). MTX was then administered at increasing doses (culminating at 4 mg/kg) daily for 60 days (n = 10 for each group). (A) Kaplan-Meier plot showing fraction of surviving mice. (B) Mean weekly hematocrit of surviving mice at each time point.