Stem Cell Breakthrough

Vancouver Sun

Commentary

Alzheimer's and Parkinson's may soon be curable diseases, thanks to a revolutionary multi-disciplinary technique developed by Canadian researchers in cooperation with researchers in Scotland. Stem cells can be created from a patient's own skin cells, using genetic engineering techniques. These stem cells are free of viruses and would not be rejected by the patient's immune system, as would be the stem cells from others. Most importantly of all, the breakthrough techniques can create essentially a limitless supply of stem cells for research and development, without the constraints of using embryonic stem cells. The debate over the ethical issues of using embryonic stem cell is irrelevant when using this new technique.

Excerpts

The ethical debate over embryonic stem cell use may soon be moot, thanks to a Canadian team of researchers who, together with a team out of Scotland, has found a safe way to grow stem cells from a patient’s own skin.

The revolutionary finding, described in a paper published yesterday by the international science journal Nature, means doctors may be one step closer to treating a multitude of diseases, including Alzheimer’s, diabetes and Parkinson’s.

Someday, the regenerative and adaptive qualities of these skin-based stem cells could be used to repair damaged organs, bones and muscles, replace brain neurons and insulin-producing pancreatic cells, and even farm new organs for transplant use.

The Canada-led discovery, headed by Dr. Andras Nagy of Toronto’s Mount Sinai Hospital, was more than a year in the making and advanced the headline-grabbing breakthroughs of U.S. and Japanese researchers in November, 2007.

While the Japanese and U.S. findings proved it was possible to create stem cells from a patient’s skin — the Japanese used cells from a 36-year-old woman’s face and the Americans used those from infant foreskins — both teams used viruses to insert the four necessary reprogramming genes into the genome of a mature skin cells. The use of viruses is associated with an increased risk of cancer and developmental disabilities and, according to the Nature paper, may also “cause unpredictable genetic dysfunction.”

Dr. Nagy’s team of 10 researchers combined their separate knowledge with that of a University of Edinburgh team led by Dr. Keisuke Kaji, becoming the first to successfully grow human stem cells without the help of viruses.

Instead, the scientists at Mount Sinai’s Samuel Lunenfeld Research Institute used an electric shock to insert the reprogramming genes into a “jumping gene” — a transformative piece of DNA found in moths, corn and other species. This jumping gene can move around to different positions within the genome of a single cell and, once a skin cell is persuaded back to its embryonic state, the jumping gene can be removed to prevent any damage.

Also, because human stem cells — also known as “induced pluripotent stems” — are bred from the patient’s own skin, they pose no threat of immune rejection, mitigating another medical drawback of embryonic stem cell use.

“This new method will advance the field of regenerative medicine, and should help understand diseases and test new drugs,” Dr. Kaji told The Daily Telegraph.

That the previously crucial ingredients — embryos or women’s eggs — are no longer essential to growing embryonic stem cells may quash the medical and ethical pushback of those who perceive stem-cell use to be dangerous or immoral.

In fact, Dr. Nagy three years ago found himself at the centre of the embryonic stem cell debate after a federal committee put on hold his project that sought to use days-old embyros. Dr. Nagy’s most recent discovery was hinged on the use of mouse and human skin cells.

This skin-cell based discovery is not Dr. Nagy’s first stem cell breakthrough: in 2005, he developed Canada’s first two human embryonic stem cell lines. Soon after in a Mount Sinai news release, Dr. Nagy said he hoped to help bring “Canada and the world closer to treating or curing diseases such as multiple sclerosis, Parkinson’s disease, Alzheimer’s disease, diabetes and spinal cord injuries.”