Phenotype and fate of liver-resident CD8 T cells during acute and chronic hepacivirus infection
Fig 4
Phenotype and function of RHV-specific T cells and analysis of memory T cell response during RHV reinfection.
(A) The frequencies and total numbers of NS31265 specific CD4 T cells in the livers of RHV infected mice. (B) Kinetics of T-bet, CXCR3, and PD-1 expression on NS31265-specific and non-specific CD4 T cells in the liver of mice. The baseline expression values of these markers in naïve mice are shown as black-filled circles. Each data represents 1–2 mice, and >6 mice were analyzed in >2 independent experiments for each time point. Statistical analyses to compare the expression of T cell marker on Tet+ and Tet- CD4 T cells were done using a two-tailed paired t-test, and only significant p-values are shown, where p-value <0.05 (*), <0.01 (**), <0.001 (***), and <0.0001 (****). (C) The % of CD8 T cells and (D) CD4 T cells producing IFN-γ, TNF-α, IL-2, and IL17 after 5-hrs ex vivo stimulation with NS3968 and NS31265 peptides at 5μg/ml concentration and analyzed by intracellular cytokine staining. (E) The proportions of NS3968-specific CD8 T cells producing IFN-γ versus TNF-α during effector (days 10, 14, and 17 p.i.) and memory (days 29 and 53 p.i.) phases. (F). RHV-cleared mice were reinfected >80 days after the first infection with a 10-times higher dose (105 VGE/mice) of mouse-adapted RHV variant to analyze the nature of viremia and recall T cell response on days 3, 5, and 10 p.i. (G) RHV reinfection was associated with a significant increase in the total number of NS3968-specific CD8 T cells and NS31265-specific CD4 T cells in the liver but not in the spleen. (H) Changes in the NS3968-specific CD8 T cells in the liver and spleen of mice after RHV reinfection. Black, light red, red, and intense-red circles depict the NS3968-specific CD8 T cells for uninfected, day 3, day 5, and day 10 time points, respectively. Asterisks show statistically significant differences: black for uninfected vs. day 3 p.i., light red for day 3 vs. day 5 p.i., and red for day 5 vs. day 10 p.i. Statistical analyses were done using a two-tailed unpaired t-test, and only significant p-values are shown, where p-value <0.05 (*), <0.01 (**), <0.001 (***), and <0.0001 (****).