Similar findings were recently reported in another mouse model of chronic haematological malignancy [38]: in the Eμ-TCL1 mouse model of chronic lymphocytic leukaemia (CLL), the authors described the expansion of IFNγ-producing CD8+ T cells in ageing transgenic mice, and effector memory T cells (at the expense of naïve T cells) in normal and transgenic ageing mice, as well as mice adoptively transplanted with CLL. The gene discussed is CD8A; the disease is B-cell chronic lymphocytic leukemia.