The number of clones contributing to marked hematopoiesis is not affected by BCNU/O6BG treatment. Representative LAM-PCR analysis of peripheral blood of mice at different time points after transplantation of 4 × 105 cells. Peripheral blood samples were analyzed before (4 weeks after transplantation) and with (A) or without (B) repetitive monthly BCNU/O6BG treatments (8, 12, 16, 20, 24, 28, and 32 weeks after transplantation). Multiple insertion sites were detected at all time points irrespective of whether the mice were treated with BCNU/O6BG. DNA (5 ng) was extracted from peripheral blood samples at each time point. M indicates a 100-bp DNA ladder; -c, negative control (5 ng DNA extracted from untransduced C57BL/6J bone marrow cells); and IC, internal control band.
