Regrowing body parts closer to reality

Scientists in Toronto are trying to crack the secrets of regeneration to trigger the human body to grow tissues and organs damaged by disease.

In his lab at Mount Sinai Hospital, Dr. Ian Rogers is working on a replacement pancreas that would be grown in a lab and then placed inthose with Type 1 diabetes to restore their insulin production.

"When I talk to parents of kids with Type 1 diabetes, I always apologize: 'Right now our goal is to treat for a year or two,'" Rogers says. "And they're very happy, because they say, 'I nag my child three times a day to take their insulin,check their glucose,' and they're saying if they get a reprieve for a year they'll be very happy."

At this stage, Rogers's team is building a pancreas out of a surgical sponge, a three-dimensional structure seeded with insulin-producing islet cells.The pancreas would be grown in the lab and then placed under the skin of those with Type 1 diabetes to restore their insulin production.

But making a pancreas is complicated, Rogers said. The most advanced research at his lab is simpler:regenerating blood vessels so people with Type 2or adult onset diabeteswho have damaged fingers and toes can avoid amputation.

In theory, any condition where cells are damaged from insulin-producing cells in diabetes to brain cells in Alzheimer's and Parkinson's disease, to retina cells in blindness, to damaged areas in the heart could one day be repaired, said Dr. Andras Nagy. The key is stem cells from blood, skin or embryos.

"If we can find a way to replace these cells back in to where it's missing, we can envision a cure for these diseases which are currently devastating," Nagy said.

So far this year, two U.S. companies gained regulatory approval to test stem cell-based therapies on 18 spinal cord patients, he noted.

Down the hall at the hospital's Samuel Lunenfeld Research Institute, Dr. Rita Kandel is working on re-growing hip and knee joints using white pieces of cartilage grown on a bone substitute that acts like a scaffold for the cells.

"The goal is to develop a biological joint replacement so that people can be fully mobile and pain free," Kandel said.

Ultimately, Kandel's vision is what she calls a fountain of youth that could cure aging, though she acknowledged that is a long way off.

For now, most of the work is still in the test tube and petri dish stage in Toronto andother laboratories around the world.