Detection of P815 leukemic cells in the peripheral blood of mice.

In mice that were protected from GVHD and that did not develop clinical signs of leukemia, peripheral blood cells were systematically collected and tested for the presence of P815 cells. On 3 of 3 and 8 of 8 protected mice treated at day 3½ or day 6, respectively, P815 cells were never detected more than 2 months after P815 cell injection, as illustrated here in a mouse treated at day 6.