A drop of stem cells restores mice’s sense of smell

A team of researchers has restored the sense of smell in a group of mice by grafting stem cells into the rodents’ noses according to new results published in Stem Cell Reports.

The stem cells, which are known as “globose basal cells,” are precursors to fully developed olfactory neurons. Once implanted into mice through a simple “nose drop delivery,” the stem cells matured into working neurons and connected to the animal’s brains, restoring their sense of smell, which had been previously rendered nonfunctional by a mutation, The Scientist reports. Whether the treatment will work in humans will likely depend on whether scientists can find a source of similar precursor cells to use for the grafting procedure.

Goldstein and others have independently tried stem cell therapies to restore olfaction in animals previously, but he and his coauthors note in their study that it’s been difficult to determine whether the regained function came from the transplant or from endogenous repair stimulated by the experimental injury to induce a loss of olfaction.

So his team developed a mouse whose resident globose basal cells only made nonfunctional neurons, and any restoration of smell would be attributed to the introduced cells.