Figure 3. Effect of time of administration of anti-CTLA-4 antibody on the abscopal effect induced by radiotherapy in TSA tumor-bearing mice.
(A) Tumor growth delay of primary irradiated tumors (left panel) and secondary non-irradiated tumor (right panel) in mice treated with PBS (closed circles), 9H10 givenatday 12, 15, 18 (open circles), 20 Gy × 1 + PBS (closed diamonds), 20 Gy × 1 + 9H10 givenatday 12, 15, 18 (open triangles), or 20 Gy × 1 + 9H10 given at day 14, 17, 20 (open diamonds). Data are the mean ± SE of 5 mice/group. No complete regression of either primary or secondary tumors was observed in any of the treatment arms. (B) Tumor growth delay of primary irradiated tumors (left panel) and secondary non-irradiated tumor (right panel) in mice treated with PBS (closed circles), 8 Gy × 3 + PBS (closed squares), 8 Gy × 3 + 9H10 given at day 12, 15, 18 (open triangles), 8Gy × 3 + 9H10 given at day 14, 17, 20 (open squares), and 8 Gy × 3 + 9H10 given at day 16, 18, 21 (open diamonds). Data are the mean ± SE of 6 mice/group. Complete regression was seen in 3 of 6 primary and 1 of 6 secondary tumors in mice treated with 8 Gy × 3 + 9H10 given at day 12, 15, 18; in 5 of 6 primary and 1 of 6 secondary tumors in mice treated with 8 Gy × 3 + 9H10 given at day 14, 17, 20; and in 1 of 6 primary and 1 of 6 secondary tumors in mice treated with 8 Gy × 3 + 9H10 given at day 16, 18, 21.