Figure 4.

PD-L1⁺ and PD-L1^– TAMs have different cell-to-cell interaction preferences

(A) Multiple immunofluorescence staining and corresponding phenotype map of representative breast tumor tissue section for PD-L1⁺ TAMs (CD68⁺PD-L1⁺), PD-L1^– TAMs (CD68⁺PD-L1^–), CD8⁺ T cells (CD8⁺), CD4⁺ T cells (CD3⁺CD8⁻), and cancer cells (CK⁺).

(B) Whole-slide quantification of the ratio of PD-L1⁺ TAMs/cancer cells in total area.

(C) Schematic representing the calculation of cell-cell interaction based on CD8⁺ T cells, CD4⁺ T cells, or cancer cells within a radius of 20 μm from the nuclei of PD-L1⁺ or PD-L1^– TAMs.

(D) CD8⁺ T cells, CD4⁺ T cells, or cancer cells within a radius of 20 μm from the nuclei of PD-L1⁺ or PD-L1^– TAMs in untreated primary luminal breast tumors (n = 36). ∗∗∗∗p < 0.0001, ∗∗p < 0.01. Wilcoxon paired test.

(E) The number of TAMs within 20 μm to PD-L1⁺ TAMs (left) or PD-L1^– TAMs (right) (n = 36). Paired t test. ∗∗∗∗p < 0.0001.

(F) Dot plots of ligand-receptor interactions between PD-L1⁺ or PD-L1^– TAMs and CD4/8⁺ T cells (left panel), and cancer cells (right panel) based on our scRNA-seq transcriptomic analysis. Gray dot represents no significant interaction was found.