Spectrum of pathogen- and model-specific histopathologies in mouse models of acute pneumonia
(A–F) Superinfection with S. pneumoniae (1 x 103 CFU/ mouse) of mice that had been infected with IAV (40 PFU/ mouse) earlier resulted in severe expansive (A), suppurative bronchopneumonia (B) with marked necrosis of bronchi which were filled up with pus (C). In addition, perivascular infiltration of neutrophils, lymphocytes and monocytes with prominent edema (D) as well as mild purely lymphocytic, dense perivascular cuffing in other areas (E) and protein-rich alveolar edema (F, asterisk) were present. (A–F) Representative images are shown. Bars (A), 1 mm; (B—F), 20 μm.