T cell-depleted bone marrow cells from WT mice, and T cells from C57BL/6 (B6) WT or Cat-Tg mice were injected into irradiated BALB/c mice along with luciferase-expressing B-cell acute lymphoblastic leukemia (B-ALL-luc) tumor cells [14,15]. The gene discussed is CAT; the disease is B-cell acute lymphoblastic leukemia.