PTL inhibits NOD/SCID repopulating ability for AML but not normal cells. Percentage of engraftment for NOD/SCID mice that received a transplant with AML (A) or normal CB (B) cells after 18 hours of culture with or without 7.5 μM PTL. Each • or ▴ represents a single animal analyzed at 6 to 8 weeks after transplantation. Each plot represents an AML/CB specimen. Mean engraftment is indicated by the horizontal bars.