Fig. 5

Baf-A1 ameliorates pneumonia in xenografted human lung tissues. Human lung sections were stained with H&E as described in the experimental procedures. A, E Images of H&E-stained Mock tissue; B, F Images of H&E-stained tissues with SARS-CoV-2 infection. The lung tissue structure was abnormally severe, with exudation of inflammatory cells into the perivascular tissues (yellow arrows), and the bronchial epithelium was hyperplastic (red arrows); C, G Images of H&E-stained tissues with Remdesivir treatment; D, H Images of H&E-stained tissues with Baf-A1 treatment. The alveolar structure is relatively clear, and the fibrous tissue hyperplasia can be seen in some areas (black arrows). I Histological score based on H&E staining indicating pathological lesions in lung tissues from Mock-infected, and SARS-CoV-2-infected mice treated with DMSO, remdesivir or Baf-A1. The score used for the measurement of damage is detailed in the methods section. Scale bar of A, B, C, D = 100 μm; Scale bar of E, F, G, H = 50 μm. Data were expressed as mean ± SEM from three independent experiments. *p < 0.05, **p < 0.01, ***p < 0.001