Figure 3. IRDye800 labelled IL-7 introduced by gavage into the stomach of a mouse pup can be detected as green fluorescence in the anterior mediastinum on the next day (A), as indicated by the white arrow.

Labelled product is apparent also around the jaws of the animal and in the intestine. The pup is in a prone position on the glass surface of the Odyssey and the image is from underneath. Two examples of samples from quantitation studies are shown here where newborn pups were fed 100 ng of labelled protein, either rIL-7 (B,C) or albumin (D,E), and culled after 24 hours and their thymus (B,D) and spleen (C,E) removed and scanned.