Immunogenicity and Cross Protection in Mice Afforded by Pandemic H1N1 Live Attenuated Influenza Vaccine Containing Wild-Type Nucleoprotein

Figure 3

Replication of H1N1 LAIVs, MDV, and wild-type influenza viruses in upper and lower respiratory tract of mice and neuroinvasion. Groups of 8 mice were inoculated i.n. with 10⁶ EID₅₀ of each virus; four mice from each group were euthanized on either day 3 or day 6 p.i. Mouse respiratory and brain tissues were collected and homogenized, and viral titers were determined by end-point titration in eggs. The virus titers are expressed as the mean log₁₀EID₅₀/ml ± SD (T-lines). The limit of virus detection was 1.2 log₁₀EID₅₀/ml, indicated by a dotted line. White bars: lungs; grey bars: nasal turbinates; black bars: brain. values were calculated by Mann–Whitney test.

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