Fig. 4
mmHERA-GITRL demonstrates single-agent in vivo efficacy that is independent of FcγR binding. a - f Freshly cultured CT26wt tumor cells (5 × 105 in 100 μl RPMI) were implanted s.c. into the right flank of 6-week-old female BALB/c mice. Tumor volume was determined twice weekly by caliper measurement. Mice were randomized on day 11 into groups of 6 mice per treatment group with a mean primary tumor volume of 101 mm3. All animals were treated (i.v.) with mmHERA-GITRL, mmHERA-GITRL (Fc+) (both at 1 or 10 mg/kg b.w.) or vehicle control (PBS) on days 11, 14, 18 and 21, indicated by the arrows. The in-life phase of the study finished on day 23 following tumor implantation. a, b Each symbol or column represents the mean (n = 6) ± S.D. b Shows the tumor volume on day 23. A two-way ANOVA plus post hoc Bonferroni multiple comparisons analysis was conducted to compare the effects of treatment and time on tumor growth. ****p < 0.0001. c – f On day 23, tumors were harvested, stained for surface marker expression and examined by FCM. c The total number of CD3+ T cells per mm3 of tumor tissue is shown. d The ratio of CD4+ to CD8+ T cells is shown. e The total number of CD4+ (closed boxes) and CD8+ (open boxes) T cells per mm3 of tumor tissue is shown. f The percentage of PD1+ cells is shown for the CD8+ T cell population. The p values represent comparisons between samples using a one-way ANOVA plus post hoc Bonferroni multiple comparisons test. *p < 0.05, **p < 0.01. Although not labeled, there are no significant differences between mmHERA-GITRL and mmHERA-GITRL (Fc+) at either dose tested