Researchers in the UK have converted skin cells into functional, mature nerve cells that act like cells found in the human body -- making them better models for studying neurodegenerative diseases like Parkinson’s and Alzheimer’s.
Several years ago, researchers showed how a group of proteins called transcription factors regulate the division and differentiation of stem cells. More recent work revealed that adding these proteins to skin cells actually reprograms them to form other cell types, including nerve cells. These are called induced neurons. But so far, only small amounts of these induced neurons can be created with existing methods, and they aren’t quite functional.
"When you reprogram cells, you're essentially converting them from one form to another but often the cells you end up with look like they come from embryos rather than looking and acting like more mature adult cells," Anna Philpott from University of Cambridge says in a news release. “In order to increase our understanding of diseases like Alzheimer's, we need to be able to work with cells that look and behave like those you would see in older individuals who have developed the disease."
By studying how nerves form in tadpoles, Philpott and colleagues found a way to push human nerve cells to mature faster. They manipulated the signals that transcription factors send to the cells, promoting differentiation and maturation -- in spite of conflicting signals directing the cell to divide.
The team was able to produce more mature cells by engineering proteins that can’t be modified by phosphate molecules. In cell division, transcription factors are activated and altered by the addition of phosphates -- a process called phosphorylation. By adding these engineered, un(der)phosphorylated transcription factors to human cells, they were able to create mature “adult” cells that could serve as models for age-related brain disorders.
The findings were published in Development this week.
[Via University of Cambridge]
Image: Fahad Ali