Figure 3. Host T cells and interferon γ mediate antitumor effect following Treg depletion. (A–E) Groups of C57BL/6 DEREG mice (n = 5–7) were inoculated s.c. with 5 × 10⁴ B16F10 melanoma cells on day 0. On days -2, 5 and 12, mice were injected i.p. with either 500 ng diphtheria toxin A (DTA) or PBS. Some mice additionally received 250 μg anti-CD4 (A), (E) and/or 100 μg anti-CD8β (B and E) anti-CD8β monoclonal antibodies on days -1, 0, 4 and 7. Some mice additionally received anti-IFNγ monoclonal antibodies on days -1 (750 μg) and 7 (250 μg) (C and E), or 100 μg anti-asialo-GM1 monoclonal antibodies on days -1, 0, 4 and 7 (D). Tumor sizes are reported as means ± SEM. Data are representative of two independent experiments.