Figure 3. NP vaccination reduces lung inflammatory mediators and damage in influenza infected young but not aged mice.

Young [Y] (2-3 mos.) and aged [A] (19-22 mos.) C57BL/6 mice were vaccinated with NP or PBS on days -31 and -21. On day 0, they were infected intranasally with 400 EID₅₀ of PR8 influenza. On 5 dpi, A. lungs were harvested and mRNA was isolated to quantitate influenza PA by real-time PCR. B. Anti-NP IgG titers in serum were determined by ELISA. Albumin C. and cytokines D. in the BAL were determined by ELISA and multiplex analysis, respectively. E. The percentage of macrophages, neutrophils and lymphocytes in the BAL was determined by differential staining. Groups labeled “none” represent BAL harvested from young or aged naive mice. Data shown is combined from 2 independent experiments and each symbol represents a single animal; line shows the mean. *p < 0.05 by 2 way ANOVA for A, B, C or 3 way ANOVA for D and E with Bonferroni posthoc correction.