Lung virus titer and inflammatory cytokine IFN-gamma.

<p>(A) Lung virus titers. Lung samples from individual mice immunized with 10 µg VLPs in each group (n = 6) were collected on day 4 post-challenge with a lethal dose of A/California/04/2009 or A/PR8/1934 virus. Each lung sample from a mouse was suspended in 1 ml with Dulbecco's modified Eagle's medium. Statistical significance is indicated between groups of mice challenged with A/California/04/2009 (P<0.001) or A/PR8/34 (P<0.01) compared to naive mice challenged with the same lethal dose. (B) Lung inflammatory cytokine IFN-γ after A/California/04/2009 challenge. (C) Lung inflammatory cytokine IFN-gamma after A/PR8/1934 challenge. H1N1 Cha, VLP immunized mice after A/California/04/2009 challenge, N+H1N1 Cha: Naïve mice after A/California/04/2009 challenge, PR8 Cha: VLP immunized mice after A/PR8/1934 challenge, N+PR8 cha: Naive mice after A/PR8/1934 challenge. Naïve: Untreated mice.