Spatial transcriptomics profiling of WT and XCR1 ⁺ depleted mice during LCMV-Arm. (A) Experimental schematic in which naïve female P14 T cells (Xist⁺) were transferred into male B6 mice followed by LCMV-Arm infection. DT administered D4–D7 after infection prior to tissue isolation at D8. (B) Quantification of CD8⁺ T cell absolute number (Xist⁻ and Xist⁺) in whole tissue section. (C) IMAP schematic of SI villus. (D) IMAP plots of P14 T cell distribution and density in WT and XCR1⁺ cell–depleted mice. (E) Representative image of transcript detection in WT and XCR1-DTR SI; colored dots correspond to labeled genes (top). Representative IMAP plots displaying P14 Xcl1 in WT and XCR1-DTR mice (bottom). (F) Histogram of gene expression in mouse (SI P14) and human (CD8αβ) T cells along crypt-villi axis. Gene labels shown, shaded bars represent T cell density. (G) Heatmap of differential gene expression in P14 T cells from WT and XCR1⁺ cell depleted mice. (H) Volcano plot displaying differential gene expression relative to P14 T cell proximity to XCR1⁺ cDC1 cells. −Log₁₀(Corrected P values) displayed. Flow validation (n = 3 per group) is representative of three independent replicates and spatial transcriptomics (n = 1 per group).