Pulmonary pathology of SARS-CoV-2 infected hACE2 mice in prophylactic treatment.

Animals challenged with SARS-CoV-2 with or without P4A2 antibody were euthanized on day 6 post-infection. The left lower lobe of their lung were fixed in 10% formalin solution and used for H & E staining. (A) Representative images of transverse section of the lung showing pneumonitis (magnification = 40×; red arrow), alveolar epithelial injury (blue arrow) and inflammation (black arrow). The stained sections were assessed by blinded-trained histologist on the scale of 0–5 (where 0 represents no feature, while 5 represents the maximum score). (B) The histological scores for each pulmonary pathology was plotted as mean ± SEM. The disease index score was calculated by taking the average score of all pulmonary pathologies (i. e. pneumonitis, alveolar epithelial injury and inflammation). Ther, therapeutic; Pro, prophylactic. NS, not statistically significant.

(PDF)