Fig. 5
High expression of IC molecules in TILs. a A comparison of the expression levels of IC molecules in peripheral blood and tumor tissue (total of 59 samples from 18 patients). IC molecules (PD-1, CTLA-4, LAG-3, and ICOS) were highly expressed in TILs compared with PBMCs. All of them were higher in CD45RA−FOXP3highCD4+ T cells (eTreg cells) than in CD8+ T cells (PD-1+CD8+ T cells and PD-1+ eTreg cells in PBMCs and in TILs [8.12% ± 5.75% vs. 12.5% ± 6.17% vs. 44.18% ± 20.7% vs. 64.01% ± 28.02%, respectively, P < 0.01 across all categories]; CTLA-4+CD8+ T cells and CTLA-4+ eTreg cells in PBMCs and in TILs [0.52% ± 0.45% vs. 20.0% ± 14.35% vs. 5.01% ± 4.35% vs. 57.96% ± 20.54%, respectively, P < 0.01 across all categories]; LAG-3+CD8+ T cells and LAG-3+ eTreg cells in PBMCs and in TILs [0.79% ± 0.78% vs. 4.05% ± 2.54% vs. 13.14% ± 6.31% vs. 18.33% ± 12.61%, respectively, P < 0.01 across all categories]; ICOS+CD8+ T cells and ICOS+ eTreg cells in PBMCs and in TILs [0.54% ± 0.51% vs. 12.94% ± 7.15% vs. 3.47% ± 2.89% vs. 50.31% ± 19.09%, respectively, P < 0.01 across all categories]). b Correlation of the expression of IC molecules in PBMCs and TILs (total of 59 samples from 18 patients). No correlation was observed between PBMCs and TILs with regard to the expression of IC molecules by CD8+ T cells or eTreg cells (PD-1, CTLA-4, LAG-3, and ICOS in CD8+ T cells, r = 0.23, 0.14, 0.13, and − 0.13, P = 0.086, 0.29, 0.34, and 0.35, respectively; in eTreg cells, r = 0.22, 0.26, 0.21, and 0.062, P = 0.094, 0.054, 0.11, and 0.65, respectively)