We performed gene expression analyses to understand the effects of r3LCMV on different cell subsets within the tumor microenvironment at day 4 after treatment. (A) Uniform manifold approximation and projection (UMAP) plots showing cell distribution based on RNA expression. Each cell is colored by its inferred subset (based on the Immunological Genome Project [ImmGen] database). Cells harboring LCMV reads are indicated by a black dot. (B) Level of expression of LCMV L and S transcripts on different cell subsets from r3LCMV-treated mice. (C) Volcano plot showing the differential expression of genes in tumor cells harboring LCMV reads versus those without LCMV reads. The dashed line indicates P value adjusted for multiple testing of 0.05. ISGs are indicated in red. (D) Enrichment for ISGs in different cell subsets. (E) ISGs on tumor cells harboring LCMV or not harboring LCMV. This panel shows that tumor cells with LCMV reads express higher levels of ISGs relative to tumor cells without LCMV reads. For each box plot, the vertical line indicates the median, the box indicates the interquartile range, and the whiskers indicate 1.5 times the interquartile range. Approximately 80% of cells were CD45⁺ (after MACS purification). Each group represents pooled tumors from 5 different mice. Indicated P values were calculated by Wilcoxon’s test.