Bioengineer Rohan Ingrole needed to floss a mouse’s teeth.
The intent wasn’t to help mice get a clean bill of health at the dentist. Each bit of store-bought floss was coated with dead influenza viruses, or lab-made bits and pieces of them. Ingrole, of Texas Tech University in Lubbock, wanted to vaccinate the animals, giving them protection against flu through their gums.
Vaccines that target the moist tissues that line cavities like the mouth or nose aim to build up immune defenses in the parts of the body that pathogens tend to invade, says Harvinder Gill, a bioengineer at North Carolina State University in Raleigh. Influenza virus, for instance,