Distribution of FITC-labelled asODN in the mouse nosein vivo. FITC-labelled asODN (80 μg/mouse) were complexed with GL67 and perfused into the nasal cavity. Twenty-four hours later the nasal septum was extracted, paraffin-embedded and processed for confocal microscopy. Nuclei are shown in blue, FITC signal is shown in green. Arrows indicate the surface epithelium. A and B are images from two different animals showing the highest (A) and lowest (B) levels of uptake seen.