Fig. 4.

Tcf7 forestalls phenotypic terminal differentiation and opposes immune cell Gzmb. (A) Gzma and Gzmb expression in three published microarray studies containing Tcf7 mutant CD8⁺ T cells. (Left) Peripheral, postinfection memory CD8⁺ T cells; (Center) thymus; and (Right) mouse DN1 stage thymocytes (Lin⁻ CD44⁺CD25⁻KIT⁺). Inset summarizes cell type and NCBI GEO accession number. (B) Plot of Gzmb vs. Tcf7 gene expression; color/shape indicate cell type. Note further annotation in plot (i.e., CD44, NK1.1), tissue/organ (i.e., adipose, spleen), or infection (i.e., MCMV, day 1 postinfection shown for NK cells responding to MCMV). For CD8⁺ T cells, d6, d8, d10, d15, d45, and d100 indicate days postinfection with Listeria monocytogenes-OVA. Primary data in B are from GSE15907. (C) Experimental diagram for retroviral transduction. (D–I) WT P14 GFP⁺-gated and FOXO1 KO P14⁺GFP⁺-gated cell numbers and phenotypes following protocol in C. Cell number and relative abundance of (D) WT and (E) FOXO1 KO. Representative KLRG1 immunophenotype with (F) KLRG1^low and KLRG1^int gates shown, and (G) pooled KLRG1 phenotype data. GZMB expression in (H) KLRG1^low and (I) KLRG1^high P14 cells. Error bars are SEM; P values are from Student’s unpaired t test. GFP, n = 9; WT GFP-TCF7, n = 7; FOXO1 KO GFP, n = 7; FOXO1 KO GFP-TCF7, n = 6. Retroviral transduction and TCF7-dependent decrease in GZMB were observed three times; pooled data are from three independent experiments plotted in G–I.