Protection in immunized young adult mice is associated with improved cellular immunity and reduced viral titers.

Abstract

<p>Young adult mice (6–8 weeks) vaccinated twice, 2 weeks apart, with Fluzone (FZ x2), Fluzone+CpG (FZ+CpG) and unvaccinated controls were challenged with 1x10⁴ p.f.u of A/California/09 H1N1. Five mice per group were sacrificed at day 7 post-infection. (A) The frequency of neutrophils (CD3-/Ly6C+) and (B) CD3+/CD8+ T-cells was measured by flow cytometry in homogenates of the right lobe of the lung. Dots represent individual mice and horizontal lines represent average +/-SEM where *p<0.05. (C) Lung virus titers from pooled mice (n = 5 per group) were determined day 7 post challenge using homogenates from the left lobe of the lung. Equal volumes of lung homogenate were pooled from 5 mice in each group and the horizontal bar represents average of duplicate wells. Data shown is representative of 2 independent experiments.</p