In a medical breakthrough researchers have turned human skin cells into working brain cells, completely bypassing the need for stem cells.
This feat comes a year after researchers at Stanford University performed the same feat in mice, turning cells from the rodents' skin into neurons. The lab-created brain cells act the same as normal human brain cells, the researchers found. These cells have the same ability to send electric signals; they seem to express the same genes in the same ways; and they are able to communicate with other brain cells, as demonstrated in a lab dish and when implanted into mice.
This study could mean newer therapies for Alzheimer's and other neurodegenerative diseases, the researchers said. In addition to transforming skin cells from healthy individuals, the researchers did the same with cells from participants with the hereditary (early-onset) version of Alzheimer's disease. These manufactured brain cells had the genetic signature of Alzheimer's and have some of the same characteristic features of Alzheimer's as cells taken directly from the brain of a patient with the early-onset Alzheimer's gene. Researchers reported several differences between these manufactured Alzheimer's brain cells and the cells of healthy patients, including the way they process and destroy a protein called the amyloid precursor protein (thought to be the main culprit of the disease). They can be used to study the mechanism of Alzheimer's development and test potential treatments, without having to harvest the cells from a living human's brain.
In earlier approaches to generate neurons from skin cells, those adult cells first had to be returned to an embryonic stem cell state. Those cells, called induced pluripotent stem (iPS) cells, are hard to come by – less than one percent of cells are typically reprogrammed successfully. In addition, the entire process is time-consuming, requiring months to coax cells into iPS cells and then stimulate them to become neurons.
This “is fundamentally different from making neurons with iPS technologies,” study researcher Asa Abeliovich, of the Columbia University Medical Center, said in a statement. “You could, in theory, take someone's skin cells and in a couple of weeks have fully functional neurons ready.” The study was published in the journal Cell.