02/03/97 SOURCE: The Ottawa Citizen
CALGARY (Canadian Press) -- Canadian medical scientists have caused lab animals to grow new brain cells in what could be a major step toward treating conditions like Alzheimer's, Parkinson's and Huntington's diseases.
``We've been able to make new brain cells in the brain,'' says Brent Reynolds, research director at NeuroSpheres Ltd., a private company.
The cells were regenerated in laboratory animals without transplanting brain tissue, Reynolds says.
And researchers at the University of Calgary have regenerated all three major cell types present in a healthy human brain in a laboratory culture.
The cells were grown using 65-year-old brain tissue obtained during a biopsy, says Samuel Weiss, a member of the university team.
``All of a sudden it doesn't seem impossible any longer to replace brain cells,'' says Weiss, whose team published a paper on regenerating animal brain cells in culture in the summer 1996 issue of the Journal of Neuroscience.
The research also opens the door to repairing brains and spinal cords damaged in accidents. Weiss says the challenge will be to target the healthy new cells toward precise locations inside the brain. The scientists say they are within two years of trying their technology in brain-injured patients.
More than 30 million people in North America suffer from Parkinson's, Alzheimer's, stroke, head and spinal injuries, Lou Gehrig's and other neurological disorders. Their health-care costs amount to $164 billion a year.
``It's important work ... the chance to actually regenerate neurons in an injured brain is really exciting,'' says University of Toronto neuro- scientist Derek van der Kooy, who has collaborated with Weiss.
But van der Kooy cautions that it is a big leap from growing cells in lab animals to an effective treatment in patients.
It has long been thought that there were no stem cells -- cells that grow new brain cells -- in adult mammals, meaning brain injury or disease causes permanent impairment. But in March 1992, Weiss and Reynolds stunned the world scientific community by finding a stem cell in the adult mouse brain. When stimulated by growth chemicals, the so-called stem cell produced new neurons, the nerve cells that ``wire'' the brain.
Since that discovery, NeuroSpheres has isolated human stem cells, grown millions of brain cells in the laboratory, and transplanted cells into several hundred test animals, Reynolds says.
``I'll be really surprised if these (lab-grown brain cells) don't go into people in two years,'' he adds.
Reynolds says company scientists are also working on regenerating cells inside a patient without cell transplants.
Weiss says his university team hopes to show within a year that motor nerve cells in the spinal cord can be regenerated, to reverse cell loss due to disabling amyotrophic lateral sclerosis, also known as Lou Gehrig's disease.
NeuroSpheres is collaborating with clinical transplant groups in Canada, the U.S. and Europe. The company has 25 employees and ongoing funding from Novartus, a giant pharmaceutical corporation.
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