Phenotypes of virus-specific CD8 T cells during acute or chronic LCMV infection. Related to Fig. 2 and Fig. 4. (A) Experimental scheme for longitudinal tracking of OT-I T cell persistence following transfer and acute viral infection with inactivation of Hdac3 at indicated time points. 5 × 10³ cells of a 1:1 mix of congenically distinct Hdac3-inducible KO (Hdac3-iKO) and Hdac3-WT OT-I cells were transferred into CD45.1⁺ TCR-polyclonal recipients. Mice were then infected intraperitoneally with 2 × 10⁵ PFU of LCMV Armstrong expressing the OVA SIINFEKL epitope (LCMV-OVA), and Hdac3 deletion was induced at the indicated time points by intraperitoneal injection of tamoxifen on 3 consecutive days. (B and C) Comparison of frequencies of transferred Hdac3-iKO (Hdac3-inducible knockout) and Hdac3-WT OT-I T cells (B) and representative flow cytometry plots of total CD8 T cells (C) in peripheral blood during and after resolution of acute LCMV-OVA infection. Data are representative of two independent experiments with three to five recipient mice per treatment group. Data from cotransferred donor cells of each genotype within the same recipient mouse were analyzed as pairs. (D and E) Analysis of the IFN-γ and TNF-α response in CD8 T cells in indicated organs on day 8 (D) and day 39 (E) of chronic LCMV clone 13 infection as measured by flow cytometry. Data are pooled from two independent experiments (D) or from one experiment (E), each with four mice per genotype except for kidney data marked †, which is from one experiment with four mice per genotype. Means ± SEM (B) or means ± SD (D and E) are indicated. P values were calculated by two-way ANOVA (B) or two-tailed Student’s t test (D and E). *, P < 0.05, **, P < 0.01, ***, P < 0.001.