FIG. 8.
Exposure to Ad7 results in infection of alveolar epithelial cells in both bovine and human lung slice models. Bovine (A to C) and human (D to F) lung tissue slices were infected with 2 × 109 PFU of Ad7/ml or mock infected with virus-free buffer (negative control), followed by incubation for 24 h. Tissue sections were prepared and immunostained for the presence of Ad7 hexon as described in Materials and Methods. Panels A and D are uninfected, negative control bovine and human lung slices, respectively, and demonstrate that Ad hexon is not detected. Panels B and E (bovine and human, respectively) show that exposure of the tissue to Ad7 results in detection of Ad hexon in multiple cells that appear morphologically to be alveolar epithelial cells. Panels C and F (bovine and human, respectively) demonstrate that omission of the anti-Ad antibody from Ad7-infected lung slices results in a loss of signal. Scale bars, 50 μm.