FIG. 2.
Histopathology, immunohistochemistry, and in situ hybridization of mouse lung tissues harvested on day 2 following infection. (A) Focal and mild peribronchiolar mononuclear inflammatory infiltrate. Hematoxylin and eosin stain; magnification, ×158. (B) SARS-CoV antigens in multiple bronchiolar epithelial cells. Immunoalkaline phosphatase staining, naphthol-fast red substrate with light hematoxylin counterstain; original magnification, ×158. (C and D) SARS-CoV nucleic acids in multiple bronchiolar epithelial cells. Immunoalkaline phosphatase staining, naphthol-fast red substrate with light hematoxylin counterstain. Original magnification: C, ×100; D, ×250.