Figure 2.

Anti-PD-L1 mAbs-mediated ADCC in human cancer cell lines. NK-92-CD16 cytotoxicity against tumor cells was measured by a standard ⁵¹Cr-release assay with various E:T ratios (30:1, 10:1, and 3:1). Bar graph represents cytotoxicity of NK-92-CD16 cells against cancer cell lines at 30:1 E:T ratio. All cancer cell lines were treated with 10 µg/mL of IgG1 isotype control (black dotted lines and bar), atezolizumab (green), IMC-001 (red), and anti-hPD-L1-hIgG1 (blue). (A) Head and neck squamous cell carcinoma cell lines. PD-L1 low (left) includes SNU-1041, SNU-1066, and Detroit 562, and PD-L1 high (right) includes SNU-1076, FaDu, and HN31 cells. (B) For non-small-cell lung cancer, NCI-H1650 cells are PD-L1 low (left), and NCI-H1975 cells are PD-L1 high (right). All experiments were performed three times independently. Statistical significance across groups 6 was determined by one-way analysis of variance. All data are shown as mean±SD. *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001. ADCC, antibody-dependent cellular cytotoxicity; E:T, effector-to-target; mAb, monoclonal antibody; NK, natural killer; ns, not significant. PD-L1; programmed death-ligand 1.