Fig. 5: Combination of PD-1 blockade with LAIR2 overexpression reduces lung tumor growth and metastasis.

a Left: Tumor volume measurements at indicated time points for 344SQ syngeneic tumors ± LAIR2 overexpression treated weekly with anti-PD-1 (200 µg/mouse) or isotype control (200 µg/mouse). Starting time of PD-1 blockade denoted by green arrow. Middle: Images of three representative 344SQ primary subcutaneous tumors for each of the indicated treatment groups. Right: Quantification of lung metastatic surface nodules in indicated treatment groups at endpoint of the experiment. For Vec Ctrl + isotype and Vec Ctrl + anti-PD-1 n = 4 mice per treatment group. For hLAIR2 + isotype and hLAIR2 + anti-PD-1 n = 5 mice per treatment group. Scale bar, 1 cm. Statistics calculated using one-way ANOVA; **p < 0.01. b Tumor volume measurements for individual mice in each treatment group from the experiment in (a). c FACS quantification for percentage of total CD8⁺ (left), PD-1⁺TIM-3⁺ exhausted CD8⁺ (middle), and CD44⁺CD62L^- effector (right) CD8⁺ TILs in indicated 344SQ tumor cell suspensions from the experiment in (a). d Representative CD8 IHC stains with quantification of 344SQ primary tumors from the experiment in (a); n = 4 tumors for Vec Ctrl + isotype and Vec Ctrl + anti-PD-1 groups; n = 5 tumors for hLAIR2 + isotype and hLAIR2 + anti-PD-1 groups, 32 total fields quantified across all tumor samples for each treatment group. Scale bars, 100µm. Inset scale bars, 20 µm. e Representative CD8 IHC stains with quantification of metastatic lung tumors from the experiment in (a); n = 4 lungs for Vec Ctrl + isotype, Vec Ctrl + anti-PD-1, and hLAIR2 + isotype groups, 17 total tumor fields quantified across all samples for each group; n = 3 lung for hLAIR2 + anti-PD-1 group with seven total tumor fields quantified across all samples. Scale bars, 100 µm. Inset scale bars, 20 µm. All data presented as mean +/− SD. Statistics calculated using a one-way ANOVA post hoc Tukey test.