Scientists convert human skin cells into brain cells

OHMYGOSSIP — For the first time, scientists have converted human skin cells directly into a type of brain cell affected by Huntington’s disease, a fatal inherited neurological disorder. The new technique is different from other methods that turn one type of cell into another because it bypasses the stem cell phase.

Researchers from Washington University School of Medicine in St. Louis found that the altered cells acted like native cells and lived for at least six months after being injected into the brains of mice.

“Not only did these transplanted cells survive in the mouse brain, they showed functional properties similar to those of native cells,” said senior author Andrew S. Yoo, Ph.D., assistant professor of developmental biology.
 
The scientists used adult human skin cells to produce brain cells called medium spiny neurons, a specific type of brain cell important in controlling movement. They are the main cells affected in Huntington’s disease, which is characterized by involuntary muscle movements and cognitive decline. Patients usually live about 20 years after symptoms begin.

Skin cells contain the DNA instructions for producing all types of cells, including brain cells. In earlier research, Yoo and his colleagues had shown that exposing skin cells to two forms of micro RNA primed them to become different types of neurons. They then added additional molecules called transcription factors that they knew existed in the part of the brain where medium spiny neurons are common. The transcription factors prompted the skin cells to become a specific sub-type of brain cell, such as medium spiny neurons.  The researchers believe they could create different types of brain cells by using different transcription factors. 
 
Numerous tests showed that the new medium spiny neurons looked and behaved like native neurons. They also expressed genes of human medium spiny neurons and not the genes for other types of neurons.

The researchers are now taking skin cells from people with Huntington’s disease and reprogramming them into medium spiny neurons and will inject them into mice with Huntington’s disease to see if their symptoms are affected.
 

The study was published in the journal Neuron.