Figure 1.
Anti-ErB2 and anti-PD-L1 mAb therapy in rat ErbB2-positive mouse tumors. (a) Her2 expression and PD-L1 upregulation on TUBO cells upon IFN-γ stimulation. TUBO cells were stimulated with recombinant mouse IFN-γ for 72 h. PD-L1 and Her-2 expression were quantified on the stimulated cells at 24, 48 and 72 h using a QIFI kit and MPDL3280A and 7.16.4 antibodies, respectively. H2N100 (b, c) and TUBO (d, e) tumor cells (5 × 105 cells) were injected subcutaneously into Balb/c wild type mice, and treated with 10 μg or 50 μg of anti-ErbB2 mAb (7.16.4), 200 μg anti-PD-L1 mAb or control Ig (200 μg) injected intraperitoneally on days 17, 21, 24 and 28. Mice were monitored for tumor growth and results are expressed as mean tumor area ± SEM. (c, e) Data is shown for the percentage of mice rejecting tumors/group (gray bars, tumor-bearing mice; black bars, tumor-free mice for at least 60 d). Arrow represents the day treatment was started. Statistical analysis was performed using two-way ANOVA Turkey’s multiple comparisons test at day 30 for B and day 39 for D (***, P < 0.0005; ****, P < 0.0001; ns: not significant).