Figure 6. Modulating CD28-mediated costimulatory signals differentially affects K^dM2_82–90 and D^bM_187–195-specific responses.

A) Mice were infected with RSV on day 0 and subsequently given IP injections of 20 µg each of antibodies against CD80 and CD86 at the indicated day post-infection. Epitope-specific CD8+ T cell responses were measured by surface and tetramer staining at 7 days post-infection. All groups were compared using a two-way ANOVA and Tukey's multiple comparisons tests, and there were no significant differences in the D^bM_187–195 response. Differences between the K^dM2_82–90 response on Day 2 and other groups are indicated below the figure (* p≤0.05, *** p≤0.001, **** p≤0.0001). B) The response ratio/immunodominance profile of CD8+ T cell responses was obtained for each mouse by dividing the K^dM2_82–90 response by the response to D^bM_187–195. * indicates p≤0.05 following one-way ANOVA and Dunnett's multiple comparisons test. C) Day 7 CD8+ T cell responses of mice injected with the indicated dose of anti-CD80 and CD86 at day 2 post-infection or isotype control antibodies (either 50 µg or 20 µg). All groups were compared using a two-way ANOVA and Tukey's multiple comparisons tests. Differences in the K^dM2_82–90 response between the 50 and 25 µg groups and all other groups are indicated below the figure (ns not significant, ** p≤0.01, and **** p≤0.0001). The D^bM_187–195 responses are significantly different between both the 50 and the 25 µg groups and isotype (p≤0.01) only. D) CD8+ T cell response ratios of mice treated with each dose of anti-CD80 and CD86 antibodies. Groups were compared with a one-way ANOVA and Tukey's multiple comparisons test (** p≤0.01, *** p≤0.001, **** p≤0.0001), and all error bars represent the SEM.