TCF-1–deficient Tc17 cells are transcriptionally distinct from other CD8⁺ T cell subsets. (A) Heat map showing DE genes by Tc17 cells (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻CD25⁺) compared with naive (TCRβ⁺CD4⁻CD8⁺CD44⁻CD62L⁺CD25⁻), effector (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻CD25⁻), and memory (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁺CD25⁻) CD8⁺ T cell populations from Tcf7^+/+ and Tcf7^−/− mice. Relative expression (Z-scores) of genes are shown; rows are scaled to have a mean of 0 and an SD of 1. For each T cell population, two independent biological replicates were analyzed. Data show the mean expression values for each group. (B) Mean-difference plot comparing Tcf7^−/− Tc17 cells with Tcf7^+/+ effector cells showing up-regulated genes in red and down-regulated genes in blue. Data show log2-fold change compared with mean expression. (C) Transcriptional profile of Tc17 cells. Intracellular analyses of the expression of T-BET, EOMES, MAF, and IRF4 in WT effector cells, Tcf7^−/− effector cells, and Tc17 cells. Effector CD8⁺ T cells were identified as TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻RORγt⁻ (effector WT, blue; Tcf7^−/−, black), while Tc17 cells were TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻RORγt⁺ (Tcf7^−/−, red). Data show the MFI of expression for each CD8⁺ T cell population and show representative profiles from one of two similar experiments (n = 4 mice/genotype). (D) Venn diagram analysis of shared genes among Tc17 cell types. Comparison of Tcf7^−/− Tc17 versus WT effector CD8⁺ T cells DE genes with DE genes in imiquimod-induced skin Tc17 cells and DE genes in topical S. epidermidis–induced Tc17 cells. Number of genes up-regulated in Tc17 cells compared with effector cells for each comparison is shown in red, and the number of down-regulated genes is shown in blue. (E) Comparison between RNA-seq analyses of murine T helper type 0 versus Th17 cells from a published dataset (GSE40918, eight libraries; Ciofani et al., 2012) with Tcf7^+/+ effector versus Tcf7^−/− Tc17 cells. (F and G) Heat map analysis showing up-regulated genes in Tc17 cells enriched for lipid metabolism (F)or wound healing (G) in Tc17 cells compared with naive, effector, and memory CD8⁺ T cell populations from Tcf7^+/+ and Tcf7^−/− mice. Relative expression (Z-scores) of genes are shown, color coded according to the legend. Rows are scaled to have a mean of 0 and an SD of 1.