Fig. 3

TANs suppress CD8 + T cells infiltration and their antitumor activities. (A) A gene plot for microarray analysis between TANs and peripheral blood neutrophils from orthotopically transplanted mouse tumors. (B) Top-ranked enriched pathways that were upregulated (black) and downregulated (red) in TANs compared with those in mouse peripheral blood neutrophils, as determined using gene ontology analysis. (C) Representative images of flow cytometry and (D) immunohistochemistry for CD8⁺ T-cells in orthotopically transplanted mouse tumors with or without neutrophil depletion. CD45⁺ cells are presented in the flow cytometry. Scale bars, 100 μm. (E) Representative images of immunohistochemistry for neutrophils (MPO) and CD8⁺ cells in the resected PDAC tissues. Scale bars, 100 μm (left). Case-1 represents severe TAN infiltration with few CD8 cells, whereas Case-2 represents limited TAN infiltration with abundant CD8 cells. The correlation between the number of neutrophils and CD8⁺ cells per field of view at 200× magnification in PDAC tissues was statistically analyzed (right, n = 31). (F–H) The percentages of PD1⁺TIM3⁺CD8⁺ T- (F), IFN-γ-producing CD8⁺ T- (G), and Granzyme B-producing CD8⁺ T- (H) cells were evaluated using flow cytometry (n = 3). **p < 0.01, ***p < 0.001; ns, not significant