Single Brain Stem Cell can Generate Copies of Itself

A recently published study shows that a single brain stem cell is capable of replacing itself, and it also can help develop specialized neurons and significant brain cells, such as glia.

The study, which was performed by Johns Hopkins University School of Medicine on adult mice, discovered that a stem cell can also generate two new brain stem cells, an unexpected feat.

"Now we know they don’t just maintain their numbers, or go down in number, but that stem cells can amplify," said Hongjun Song, PhD, professor of neurology and neuroscience and director of the Stem Cell Program in the Institute for Cell Engineering at Hopkins.

Before this study, it was known that a green fluorescent protein-labeled neural stem cell clone possesses the “mother stem cell” with neuronal and astroglial progeny.

The mice used in this study were genetically modified with color-coded cells, making labeling and tracking simpler. The researchers injected a miniscule quantity of a chemical into about fifty of the brains of the study mice in order to induce precise and limited cell labeling.

Using a specially developed computer program, the researchers devised a new imaging technique that allowed them to examine stained slices of the mouse brain. This allowed them to focus on solitary radial glia-type stem cells over time.

"We discovered that single cells in an intact animal nervous system absolutely do exhibit stem-cell properties; they are capable of both replicating themselves and producing different types of differentiated neural progeny," said Guo-li Ming, associate professor of neurology and neuroscience at Hopkins.

The researchers monitored all of the marked radial glia-type stem cells for a minimum of one month; one year later, they found that even over the extended period of time, the “mother” cell was still generating its duplicate, along with diverse types of progeny.

"If we can somehow cash in on this newly discovered property of stem cells in the brain, and find ways to intervene so they divide more, then we might actually increase their numbers instead of losing them over time, which is what normally happens, perhaps due to aging or diseases," stated Song.

The study appears in the journal Cell.