Canadian researchers have discovered a new class of stem cells they say could be safer and better to use in medical research, which could eventually lead to new uses for treating illnesses.

Since the discovery of stem cells by scientists in Toronto about 50 years ago, 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.

By understanding how stem cells work, Andras Nagy and other researchers aim to maximize their clinical potential. (Kelly Crowe/CBC)

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 in trying to use pluripotent stem cells in a controlled way, tumours can 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.

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.

"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."

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.

Funding pressures

The discovery comes at a time when governments are increasingly forcing scientists to find private sector partners to get public research money, said Tim Caufield, a University of Alberta health law researcher who has been in the stem cell field since the late 1990s.

"There is incredible pressure on the research community to produce [commercially viable], near-term products that are going to produce a return on investment and are also going to drive the economy," Caufield said.

Nagy says there's a danger in funding science with the goal top of mind because many great inventions only come about once there's a knowledge base. Nagy gives examples from his own lab.

"Suddenly what we are getting from the experiment didn't fit into our original hypothesis. Then we start thinking, 'what is happening here?' They gave us the big stories published in Nature."