Figure 6. T-cell-dependent tumour rejection in Tlr3/7/9^−/− mice.

(a) Depleting antibodies against CD4 and CD8 were injected into 12- to 17-week-old C57BL/6 WT and Tlr3/7/9^−/− mice. Control mice were treated with appropriate isotype. Tumour growth was measured every other day. Mean±s.e.m. of four to eight mice per group. Results were considered significant at *P⩽0.05 and **P⩽0.005 (t-test). (b) To deplete myeloid regulatory cells, treatment of 11- to 17-week-old C57BL/6 Tlr3/7/9^−/− mice with the αGr-1 antibody started before tumour cell injection and was continued throughout the whole experiment (n=4). The control group was treated with isotype antibodies (n=2). Depletion was monitored in the peripheral blood using flow cytometry and is indicated by the green line. One representative experiment out of two is shown. (c) Tumour cells (0.5 × 10⁶) were injected s.c. into the right flank of Tlr3/7/9^−/− mice (Tlr3/7/9^−/− regressor, blue). After tumour rejection (red arrow), the same mice were injected on the opposite flank with the same number of tumour cells. Naive Tlr3/7/9^−/− (grey) and C57BL/6 WT mice (black) were also injected and served as controls. At the time of rechallenge, mice were 24–26 weeks old. Tumour size was measured every other day. The mean tumour volume±s.e.m. of three to five mice per group is shown.