GVL is directed against miHAs shared by normal and leukemic stem cells. (A) Survival curve for B10.D2→Balb/c mixed allogeneic chimeras with CML who were untreated (red curve), or treated with weekly DLI (total of 3 infusions beginning at day 14 after BMT) of syngeneic (Balb/c) or allogeneic (B10.D2, black curve) DLI. For syngeneic DLI, splenocytes were given either unfractionated (blue curve) or after depletion of CD25⁺ regulatory T cells (purple curve). (B) Schematic diagram of secondary transplantation experiment. BM from primary chimeras (B10.D2→Balb/c) treated with allogeneic DLI + imatinib, DLI alone, imatinib alone, or no treatment was transplanted to sublethally (450 cGy) irradiated syngeneic female Balb/c recipients. The secondary transplantation was performed either at the time of morbidity or death of the primary chimera or at least 100 days after the primary transplantation. (C) Survival curve of secondary recipients of BM from primary leukemic chimeras that were untreated (Control) or treated with imatinib only, allogeneic DLI only, or the combination of DLI + imatinib. Note that in this experiment, imatinib treatment decreased the efficiency of secondary transplantation of CML-like leukemia to 50%. (D) PCR assay for male Sry sequences in hematopoietic tissues (S = spleen, B = BM, and L = lymph node) of the secondary recipients from panel C.