Fig 4.

Ad5-HA vaccination elicits IAV-specific IgG and IgA in the lung. Pigs were vaccinated with Ad5-empty or Ad5-HA (CA09) intranasally 42 days prior to infection with A/CA/04/09 (CA09) or A/SW/MN/2011/08 (MN08). ELISA plates were coated with CA09 or MN08 as the antigen, and levels of IgA (A and C) and IgG (B and D) antibodies in BALF samples (diluted as described in Materials and Methods) collected 5 days after infection with the indicated challenge virus are shown. Results are reported as the mean OD ± SEM for each group. Statistical differences between nonvaccinated and vaccinated groups challenged with the same virus are indicated with connecting bars and asterisks (P ≤ 0.05).