Fig. 4: β-glucan treatment drives Kupffer cell – T cell interactions.

a Representative images of livers from mice at 14 day after iPo injection of PDAC-YFP tumor cells. Tissues stained using mIHC to detect YFP⁺ tumor cells (teal), CD3 (purple), F4/80 (yellow), Clec4f (brown), and nuclei (blue, hematoxylin). Images show T cells in contact with (1) no macrophage, (2) a BMDM, (3) a KC and (4) both a BMDM and a KC. Scale bar, 25μm. b Quantification of cell-cell interactions between T cells (CD3⁺) and liver macrophage subsets (Clec4f⁺F4/80⁺, KCs; F4/80⁺, BMDMs) in mouse livers of control and BG-treated mice at 14 days after iPo injection of 200,000 PDAC-YFP tumor cells (n = 9 mice/grp). One-way ANOVA with Tukey’s test. Mean ± SD is shown. c Pie charts summarizing data shown in (b). d UMAP of T cell/NK populations identified by scRNAseq in control and BG-treated livers on day 2. e Dot plot of Log₂ Fold-Change in T cell/NK population frequency in BG-treated livers compared to control livers. Size represents the proportion of total T cell/NK and color indicates the number of differentially expressed genes in BG versus control. f, Volcano plot of differentially expressed genes by pseudobulk analysis among Cxcr6 CD4⁺ T cells in control versus BG-treated livers. Annotations highlight genes associated with the cell cycle (red), cell differentiation (yellow), IFN (blue) and cell migration (green). Significance determined by log2FoldChange < −0.5 or > 0.5 and adjusted p value < 0.05. g–j Heatmaps of cell cycle (g), IFN-related (h), cell differentiation (i) and cell migration (j) gene set associated genes, differentially expressed in Cxcr6 CD4⁺ T cells from control and BG-treated livers on day 2. Scale bars indicate log₂[TPM] scaled by row across samples. BMDM, bone marrow-derived macrophage; KC, Kupffer cell; scRNAseq, single-cell RNA sequencing; Ctrl, control; IFN, interferon.