Figure 1.

NK cells expanded from lung cancer patients (LCPs) exert strong antitumor activity against patient tumors and rescue tumor killing by endogenous TILs. NK cells were expanded from the peripheral blood (pbNK), pleural effusions (peNK) or tumors (taNK) of LCPs or peripheral blood of healthy donors (HD). (A) Fold expansion of NK cells from PDL1+ versus PDL1− tumors and representative flow plots showing NK cell (CD56+CD3-) purity pre-expansion and postexpansion. Expression of activation (B) and inhibitory (C) receptors on exNK cells from PDL1+ and PDL1− tumors at 28-day expansion. (D) Five-hour killing of human A549 lung cancer cells by exNK cells. (E) Schematic: exNK cells were adoptively transferred to NRG mice 2 and 5 days after intravenous infusion of Luciferase-expressing A549s (A549-Luc). Graph: quantification of tumor burden via bioluminescence at the indicated days. (F–I) Expanded LCP taNK and pbNK cells were coincubated with LCP tumors. Five-hour (F) killing and relative increase in (G) degranulation (CD107a) and (H) IFNγ expression against patient tumors compared with expanded HD pbNK cells against these same patient tumors. (I) Representative flow plots of NK cell CD107a and IFNγ expression. (J) Schematic: patient tumors were seeded in transwell on apical and basolateral surfaces. exNK cells or rhIFNγ (20 ng/mL) or neither (basal) were added to the apical chamber. Graph shows killing of tumors in the basolateral chamber by endogenous TILs after 48 hours. (K) Schematic summarizing results. Data show means±SEM of three to eight replicates per condition. Results analyzed by two-way ANOVA (A, D, E, G, H), unpaired t-test (B, C) or one-way ANOVA (D, F, J). **P<0.01, ***p<0.001, ****p<0.000. ANOVA, analysis of variance; exNK, expanded NK; IFNγ, interferon-gamma; NK, natural killer; NRG, NOD-Rag1^null IL2rg^null; ns, not significant; PDL1, programmed death receptor ligand-1; rhIFNγ, recombinant human IFNγ; TILs, tumor-infiltrating lymphocytes.