To assess the clinical effect of IL-2 therapy for recipients with active tumor, recipient B6D2F1 mice were irradiated with 10 Gy, and transplanted with 5 × 106 spleen cells and 5 × 106 TCD-BM from B6 (syngeneic) or B6D2F1 (allogeneic) mice, along with 2.5 × 104 P815 (H-2Kd) cells expressing luciferase (Figure 6A). Here, IL2 is linked to neoplasm.