Skip to main content
. 2023 Mar 10;193(6):690–701. doi: 10.1016/j.ajpath.2023.02.013

Figure 1.

Figure 1

Combined pulmonary pathology severity score summary and photomicrographs of hematoxylin and eosin–stained lung sections from uninfected and SARS-CoV-2–inoculated hamsters at 3 and 6 days post inoculation (dpi). A: The proportion of lung surface area exhibiting SARS-CoV-2–induced microscopic lesions (top panel) and the mean pulmonary vascular histology severity score (bottom panel) increase from 3 to 7 dpi in group 1 and 2 SARS-CoV-2–inoculated hamsters. Scores are significantly higher in SARS-CoV-2–inoculated hamsters than in mock-inoculated control animals (U-test). Horizontal lines denote means. Each dot/square indicates an individual hamster. B: Normal lung from uninfected hamster. C: Lung from a SARS-CoV-2–inoculated hamster euthanized at 3 dpi. There is patchy necrohemorrhagic bronchiolitis and loss of normal alveolar septal architecture with replacement by hemorrhage, fibrin, and an inflammatory infiltrate (asterisks; middle panel) composed primarily of neutrophils and macrophages (not shown here but identifiable at higher magnification), with scattered multinucleated syncytial cells (inset; middle panel) and mononuclear endotheliitis (arrows; right panel) with perivascular inflammation. D: Lung from a SARS-CoV-2–inoculated hamster euthanized at 6 dpi. There is widespread broncho-interstitial pneumonia (asterisks; middle panel) with bronchiolar epithelial hyperplasia (arrowheads; middle panel) and multinucleated syncytial cells (inset; middle panel). Right panel: Endotheliitis (arrows) and perivascular inflammation remain prominent. ∗P ≤ 0.05, ∗∗P ≤ 0.01. Scale bars: 1 mm (B–D, left panels); 30 μm (B–D, middle panels); 20 μm (B–D, right panels); 10 μm (C and D, insets). A, alveolar septa; B, bronchiole; BV, blood vessel; DPBS, Dulbecco’s phosphate-buffered saline; PFU, plaque-forming unit.