Various ways exist to deliver adult stem cells for repair of tissues, such as injection directly into the tissue site or by intravenous injection. Now comes a new, novel way to deliver stem cells to the brain--snort them. Scientists at the University Hospital of Tubingen in Germany presented evidence using mice that snorting stem cells up the nose is an effective way to deliver the cells to the brain. Basically they put stem cells into nose drops, put the drops up the noses of the mice, and the mice snorted the suspension high into their noses. The stem cells then crossed into the brain. They were able to track migration of the fluorescently-labeled stem cells through the brain.

This gives "up your nose" a whole new meaning for stem cells.