FIG 9.
Effector functions of recall CD8 and CD4 T cells in influenza virus-challenged wild-type (WT) and CCR2−/− mice. At 50 days after booster vaccination, WT or CCR2−/− mice were challenged with H1N1/PR8 strain of influenza A virus. On day 6 after viral challenge, functions of antigen-specific CD4 and CD8 T cells in lungs were analyzed. (A) Single-cell suspensions of lungs were stained directly ex vivo with Db/NP366 tetramers along with anti-CD8, anti-CD44, and anti-granzyme B antibodies. FACS plots are gated on tetramer-binding CD8 T cells, and numbers are percentages of granzyme B+ve cells among the gated population. (B and C) Single-cell suspensions of lungs were cultured with NP366 or NP311 peptides, and IFN-γ- and/or IL-17α-producing CD8 or CD4 T cells were quantified by intracellular cytokine staining. Plots are gated on total CD8 and CD4 T cells, respectively. Numbers are percentages of IFN-γ- and/or IL-17-α-producing cells among the gated population. Data are representative of two independent experiments. Mann-Whitney U test; *, **, and *** indicate significance at P values of <0.05, <0.01, and <0.001, respectively.