Since the discovery of stem cells by scientists in Toronto in 1963, researchers have hoped the cells could be used to repair damaged or diseased tissue, thanks to their ability to create all of the cells in our body.
So far, embryonic stem cells have been used to treat eye disease in a small number of people and are being investigated to treat many more illnesses by replacing missing cells or damaged tissue.
In experiments, scientists rewind adult cells into a primitive or "pluripotent" state that mimics embryonic stem cells. But using pluripotent stem cells in a controlled way can cause tumours to form.
In Wednesday’s issue of the journal Nature, Andras Nagy of Toronto’s Mount Sinai Hospital and his colleagues describe a new class of the cells in mice that could be used in biology and medical research experiments and perhaps future medicines.
"We do believe that if we are opening up this black box and put some light into it and even videotape what’s happening inside we will be able to understand this process better," Nagy said. "That knowledge that we are generating would help us to make safer cells at the end, maybe more efficient cells to treat diseases."
Nagy and his team called the cells F-class after their fuzzy appearance.
But whether F-class cells can be safely used in the clinic is still not clear and remains years away from being answered.
In a second paper, Nagy’s team also mapped the stages the cell goes through to revert back to a primitive form, taking a series of snapshots of the steps along the way.
Another three studies published in Nature Communications describe the reprogramming in more detail.
Scientists have been reprogramming adults cells for decades, but they’re only just beginning to understand how it works, Jun Wu and Juan Carlos Izpisua Belmonte of the Salk Institute for Biological Studies in La Jolla, Calif., said in a journal commentary published with the research.
"These five manuscripts mark the first steps towards understanding F-class pluripotency and thus towards making the most of their clinical potential," Wu and Belmonte said.