Figure 5.

Defective secondary responses in IL-21Rα^−/− mice are due to abnormalities in CD8⁺ T cells (A) WT and IL-21Rα^−/− mice were inoculated with rAd-gp140 and sacrificed 44 days post-inoculation. Splenocytes were subjected to intracellular cytokine staining. Data are presented as the percentages of CD4⁺ T cells staining positively for IL-17A, IL-2, TNF-α, or IFN-γ and represent the means ± SE of 11 mice per group and are representative of three experiments. (B) WT and IL-21Rα^−/− mice were inoculated with rAd-gp140 and then re-inoculated with rAd-gp140 eight weeks later and then sacrificed 21 days post-secondary inoculation. Splenocytes were subjected to intracellular cytokine staining. Data are presented as the percentages of CD4⁺ T cells staining positively for IL-17A, IL-2, TNF-α, and IFN-γ and represent the means ± SE of four mice per group and are representative of three experiments. (C) Irradiated mice were reconstituted with either WT Thy1.1⁺ or IL-21Rα^−/− Thy 1.2⁺ bone marrow cells and then inoculated with rAd-gp140 six weeks later. These mice were then re-inoculated with rAd-gp140 eight weeks later and p18-specific CD8⁺ T cells were quantitated with an H-2D^d/p18 tetramer. Data are presented as the percentages of Thy1.1⁺ or Thy 1.2⁺ CD8⁺ T cells that bind tetramer and represent the means of six mice per group ± SE and are representative of two experiments. (D) Irradiated mice were reconstituted with WT Thy1.1⁺ and IL-21Rα^−/− Thy 1.2⁺ bone marrow cells and then inoculated with rAd-gp140 six weeks later. These mice were then re-inoculated with rAd-gp140 eight weeks later and p18-specific CD8⁺ T cells were quantitated with an H-2D^d/p18 tetramer. Data are presented as the percentages of Thy1.1⁺ or Thy1.2⁺ CD8⁺ T cells that bind tetramer and represent the means of six mice per group ± SE and are representative of two experiments. The Mann–Whitney test was used for statistical comparisons.