Figure 5.

Light photomicrograph of lung sections of mice injected with DOTAP:cholesterol liposomes followed by Ad virus containing LacZ cDNA. Three days following the injection, mice were killed and lungs were perfused intravascularly with 2% paraformaldehyde and incubated in X-gal solution overnight at 37°C. The lungs were then embedded in paraffin and thin sections were prepared. The sections were counterstained with eosin and viewed with a Nikon light microscope. There was no detectable LacZ expression in the lung of control mouse injected with AdCMVLuc (a). In contrast, there was localized expression throughout the distal lung of mice injected with AdCMVLacZ (b). Expression was seen in structures within the alveolar septum that appeared to be capillary endothelium.