When Mount Sinai Hospital researcher Dr. Andras Nagy initiated a huge project to demystify the process by which specialized cells become stem cells, he wasn’t expecting to discover a whole new type of stem cell.
It’s a big finding, because “identifying a new class of stem cells means a 100 per cent increase in possible sources” of cells for therapeutic use.
He describes a stem cell as “a blank tablet.” They hold great potential to treat diseases that result from damaged tissue or loss of cells, such as Alzheimer’s, spinal cord injuries and blindness.
His latest research, dubbed Project Grandiose because of its sheer scale, has involved employing a team of nearly 50 researchers across four continents to document the process of creating stem cells. These cells — called induced pluripotent stem cells, or iPS cells — can be used to form any type of cell in the body as an alternative to using the more controversial stem cells derived from embryos.
The findings will be published Thursday in a package of papers in Nature and Nature Communications .
The oldest example of a therapy based on stem calls is bone marrow transplants, which have been performed for more than 40 years.
One of the newest applications of stem cells is treating and preventing the loss of vision using iPS cells. Japan has permitted the use of these cells to regenerate eye tissue this year. A woman in her 70s was the first to receive retinal tissue created from iPS cells to combat a degenerative condition that can lead to blindness.
Nagy characterizes this procedure as an “icebreaker,” hoping it will lead to further treatment and perhaps even cures in other diseases.
But understanding these cells first is key to safer use.
“If we understand this process better and deeper, we will be in a better position to create safer and (more therapeutically useful) cell types in the future,” said Nagy.
In examining this process in “high-definition,” the research team discovered a new type of stem cell — the F-class iPS cell. This is significant not only because it may mean there are even more types of stem cells, but also because F-class cells are easier and cheaper to grow as compared to iPS cells, said Nagy.
He also notes that F-class cells may be better for treating neuro-generative diseases such as Parkinson’s.
The discovery of F-class cells wouldn’t have been possible without the work of Dr. Shinya Yamanaka of Kyoto University, who achieved a major breakthrough in 2006 when his research showed specialized mouse cells could be converted into a pluripotent cell without the use of embryo cells, now known as the iPS cell. Yamanaka received a Nobel Prize for his research in 2012.
Stem cells were first discovered by physician Ernest McCulloch and biophysicist James Till in research published in 1961, while they were working out of the Ontario Cancer Institute at Princess Margaret Hospital. The pair discovered the unique properties of these cells, namely that they can renew themselves and turn into any other kind of cell.
Nagy has contributed to the Canadian legacy of stem cell research since arriving from Hungary in 1988 to join Mount Sinai Hospital’s Samuel Lunenfeld Research Institute, renamed the Lunenfeld – Tanenbaum Research Institute in 2013. He says Toronto has provided fertile ground for stem cell research.
“We have massive institutions focusing and investing in this new area of medicine,” said Nagy.
He created Canada’s first human embryonic stem cell lines in 2005. In 2009, he was recognized by in Scientific American magazine’s inaugural Top 10 awards for his work reprogramming adult skin cells into iPS cells .
In 2011, Nagy was one of the researchers who discovered a high level of mutations when converting adult cells, which ultimately led to the latest project to examine what exactly happens during the conversion process.
And he’s ready for the next phase of work.
“We are very, very close to provide treatment to diseases which are currently incurable and devastating,” said Nagy. “That’s what keeps the excitement in my lab.”
With files from Joseph Hall and Megan Ogilvie.
Clarification – December 2011: This article was edited from a previous version that referred to the Lunenfeld-Tanenbaum Research Institute by its name in 1988.