Mouse BM cells transduced with ERG induce leukemia in hosts that received a transplant. (A) FACS analysis of GFP expression in infected BM cells immediately after infection with GFP-only control and ERG-containing viruses. (B) Western blot analysis of lysates from cells sorted immediately after infection with the use of anti-Flag and antitubulin antibodies. (C) Kaplan-Meier survival curve for cohorts of mice that received a transplant with BM cells transduced with the indicated viruses (n = 8 for vector control; n = 9 for ERG). (D) Splenomegaly (left) and enlarged thymus (right) in mice that received a transplant with cells expressing ERG. (E) Leukemic cell infiltration into organs (spleen, thymus, and liver) was determined with the use of H&E staining. Original magnifications: upper panels, ×40 (SPlan4 4×/0.13 160/-objective); lower panels, ×200 (SPlan20 20×/0.46 160/0.17 objective). (F) Weights of spleen and thymus of mice that received a transplant with cells infected with control and ERG-containing viruses. (G) Percentage of GFP among Ly5.2 donor cells repopulated in thymus of Ly5.1 host mice that received a transplant. Open and filled circles represent control and ERG-transduced cells, respectively. Here, “a” to “i” correspond to mice used for the flow cytometric analysis shown in Figure 2A, Southern blot analysis shown in Figure 3C, and mutational analysis shown in Table 1.