In MHC (H-2b)-matched C3H.SW (H60null) → Con-H60 allo-BMT, transfer of CD8 T cells from H60-vaccinated donors, containing 2,600–5,000 H60-tetramer+ cells, prolonged the survival of the H60+ tumor-bearing hosts with chronic phase or blast crisis chronic myeloid leukemia (CML) (70, 71). This evidence concerns the gene CD8A and chronic myelogenous leukemia, BCR-ABL1 positive.