Deficiency in TCF-1 and LEF-1 compromised maturation and function of memory CD8+ T cells. A. Numbers of memory CD8+ T cells. Ova-specific IFN-γ+GFP+CD8+ T cells were detected in the spleens on day 35 post-infection. Data are means ± s.d. from 4 independent experiments (n ≥ 9). B. Phenotypic characterization of memory CD8+ T cells. KLRG1 and IL-7Rα expression was determined on splenic Ova-specific IFN-γ+GFP+ memory CD8+ T cells. The percentage of each subset is shown in representative contour plots from 2 experiments (n ≥ 4). C. Cumulative frequency of KLRG1loIL-7Rα+ memory CD8+ T cells. For A and C, *, p<0.05; **, p<0.01; ***, p<0.001; n.s., not significant. D. Functional characterization of memory CD8+ T cells. IL-2, TNF-α or granzyme B was detected by intracellular staining in IFN-γ+GFP+ memory CD8+ T cells on day 35 post-infection. The percentages of positive subsets are shown. Data are representative of 3 independent experiments (n ≥ 6).