Fig. 7.

Administration of anti-IL-1β neutralizing polyclonal antibodies restrains development of inflammation in the lungs of mice infected with influenza A virus. Groups of mice received 100 μL of anti-mouse IL-1β neutralizing polyclonal antibodies, mouse IgG at 1 mg/mL, or saline prior to infection. After administration for 1 hour, 25 pfu of PR8 in 15 μL of saline or saline alone was instilled intranasally. At day 7 postinfection, mice were sacrificed and isolated lungs were prepared for hematoxylin and eosin staining. Images of histological analysis were acquired with a microscope (BZ-X710) with 2 × magnification (A). The hypercellular areas shown in red and the hypocellular areas shown in green were quantified in the lung. The percentage of the whole lung occupied by hypercellular areas was determined using BZ-X analyzer software (B). Scale bar, 300 μm. *, P < 0.05 by Student’s t-test