Histological lesions in lung sections from immunized mice after challenge with pH1N1.

<p>Separated mice (n = 4 mice/group) from each group were sacrificed 6 or 7 days post challenge, and their lungs were HE-stained for histological evaluation. (A) Non-infected BABL/c mice; (B) mice injected with PBS; (C) mice injected with AcHERV-GmCSF; (D) mice vaccinated with 0.2 μg of killed vaccine; (E) mice vaccinated with 0.2 μg of killed vaccine together with AcHERV-GmCSF; and (F) mice vaccinated with 2 μg of killed vaccine. Arrows indicated the infiltration of inflammatory cells, including the infiltration in the vessels, in the pulmonary parenchyma, and in the alveolar septa. Scale bar, 100 μm.