TBI dose-dependent engraftment of transgenic marrow cells in sublethally irradiated BMT recipients.

Survivors from Figure 1 were killed 120 days after transplantation. Genomic DNA was isolated from bone marrow and spleen and subjected to quantitative Southern analysis as described in “Materials and Methods” (see Figure 4A for an example of the Southern hybridization signals used to quantitate DHFR transgenic cell engraftment levels). Values are presented as mean ± SD of between 5 and 9 samples. Results of statistical analyses between PBS- and MTX-administered animals are given as P values, displayed above each pair of groups.