Vaccination against tumors is more efficient in Ccl22^−/− mice. (A and B) Ccl22^−/− and WT C57BL/6 mice were injected subcutaneously with Panc02-OVA tumors. 1 wk after tumor induction, mice were vaccinated twice with OVA at a 7-d interval as described in Fig. 3, and tumor size as well as survival was monitored (n = 14 mice per group). Growth curves are depicted up to the time point of >20% deaths in one group. Data are shown as mean ± SEM and are pooled from two independent experiments. In total three experiments with similar results were performed. (C) 1 wk after the last vaccination, OVA-specific T cells in the peripheral blood of the mice (n = 8, one of three experiments with similar results) were determined as described in Fig. 3. Data are shown as mean ± SE. *, P < 0.05; **, P < 0.01; ***, P < 0.001 (two-sided Student’s t test and two-way ANOVA).