Fig. 2
Survival benefit conferred by anti-GITR (1)/SRS treatment of murine glioma requires CD4+ T cells. C57/BL6 mice were inoculated with intracranial GL261-luc tumor, randomized to ≥7 mice per group and administered anti-GITR (1) and SRS as in Fig. 1. Mice were injected i.p. with 200 μl anti-CD4 (10 mg/kg) a and anti-CD8 (10 mg/kg) b depleting antibodies on days 5–7, 14, and 28 and followed for survival. Curve-adjacent asterisks compare indicated curve to control. The same control, anti-GITR (1), and anti-GITR (1)/SRS groups were used in (a) and (b) as the experiments were performed concurrently. The difference in survival between control mice and mice depleted of CD8+ T cells was statistically significant, but was not significant in the absence of CD4+ cells. FoxP3DTR mice were inoculated intracranially with 1.3 × 105 GL261-luc cells, randomized, injected i.p. with 200 μl of diphtheria toxin (50 ng/g) on day 8, 9 and every 2 days thereafter in order to achieve FoxP3+ cell depletion, administered anti-GITR (1) or SRS as in Fig. 1., and followed for tumor growth by bioluminescent imaging c. Tumor size was quantified by bioluminescence d. *P < .05; **P < .01. NS, non-significant