NOD-Scid injected with CCRF-CEM cells develop T-ALL. (A) A representative experiment showing that CCRF-CEM–bearing NOD-Scid mice have an increased accumulation of human CD5⁺ cells in the spleens after 30 days of tumor injection. (B-C) Spleens from panel A were tested for the expression cyclin D3 and GAPDH by Western blot and for the cell-cycle progression using propidium iodide. The experiments were repeated a minimum of 3 times obtaining similar results.