Lirilumab therapy improves survival in a therapeutic HLA⁺tumor model in an NK-cell–dependent manner. (A) Schema of lirilumab administration. (B) To determine therapeutic efficacy of anti-KIR mAb therapy and the role of NK cells, 221 HLA-Cw3 tumor cells (10⁷ cells) were injected intravenously into Rag1KO-Tg KIR mice and, starting 5 days after tumor challenge, groups (n = 8 mice per group) received (○) no treatment, (♢) isotype control at 0.5 mg/kg, (●) lirilumab at 0.5 mg/kg, or (▪) lirilumab at 0.5 mg/kg and 100 µg anti-NK1.1 mAb to deplete NK cells starting on the day prior to tumor inoculation. Mice were then monitored for overall survival. *P = .0002. One experiment representative of 2 experiments is shown.