Single-cell transcriptomic analysis of Tregs in the tumors. (A) UMAP visualization of single-cell transcriptomes of Treg cells isolated from PBS- and rMVA-treated tumors. Each dot corresponds to a single cell and each color represents one cluster. (B) Violin plots showing the expression levels of selected marker genes in different Treg cell clusters. (C) Violin plots showing the expression levels of top enriched genes in different Treg cell clusters. (D) UMAP showing the expression of selected marker genes for each Treg cell cluster. (E) Volcano plots showing genes differentially expressed between clusters 3 vs. 4, clusters 2 vs. 3, and clusters 2 vs. 4.