Fig. 5

Antagonistic effects of the 53X tribodies tested by Competitive ELISA assays. The ELISA assays were performed by measuring the binding of each biotinylated chimeric PD-L1 or MHC II protein (striped bars) to immobilized PD-1 (A-B) or LAG-3 (C) proteins, respectively, in the absence or in the presence of the unlabelled competitive anti-PD-L1 (53L1 and 53L10) (A), anti-PD-1 (53D) (B) or anti-LAG-3 (53G) (C) tribodies (black bars) or their respective parental mAbs (grey bars) used at saturating concentrations (5:1 M/M for anti-PD-L1 or anti-PD-1, and 3:1 M/M for anti-LAG-3 excess ratio). Unrelated IgGs were used as negative controls (empty bars). Binding values were reported as the mean of at least three determinations obtained in three independent experiments. Error bars depicted means ± SD. P-values for the indicated compounds are: ** P < 0.01; * P < 0.05 by student’s t-test (two variables)