Figure 3
Therapeutic effectiveness of Surek. Survival of mice i.p. injected with different numbers of B78-D14 tumor cells followed by Surek therapy was evaluated. Mice were administered with either 1 × 105 (A) or with 2 × 105 (B) B78-D14 cells and subsequently received three injections of Surek antibody within 11 days, except for the tumor control. Three dosing groups of 3, 10 and 50 μg antibody were performed. Each group comprised 9 mice. Asterisks indicate statistical significance in comparison to the control group according to the log rank test with p values of < 0.05 (*), < 0.01 (**), and < 0.001 (***), respectively. (C) Superior therapeutic effect of Surek in comparison with the parental anti-GD2 antibody Me361 and the control trAb TRBs01 (anti-HER2/neu x anti-mCD3) was observed. Mice were challenged i.p. with 5 × 105 B78-D14 cells and treated with three injections of either 50 μg Surek (n=15), 50 μg Me361 (n=16), or 50 μg TRBs01 (n=10) antibody, or left untreated (control, n=10). Survival of mice treated with Surek was significantly prolonged in comparison to the Me361 and TRBs01 treatment groups (log-rank test, p < 0.0001). (D) The therapeutic activity of Surek depends on the presence of T cells. Mice (n=6) were challenged i.p. with 1 × 105 B78-D14 cells on day 0 and treated with 10 μg Surek on days 2 and 10 after tumor challenge. T cells were abrogated by injection of depletion antibodies RmCD4 and RmCD8 on days −4, 1 and 14.