CD8A and chronic myelogenous leukemia, BCR-ABL1 positive: While IgG-treated control H2–/– CML mice were protected from CML development and survived long-term, CD8+ CTL depletion completely restored the competence of H2–/– CML mice to develop leukemia and resulted in death of the mice approximately 20–30 days after transplantation (Figure 6, M and N).