Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: FRIDAY, May 4, 1990 TAG: 9005040841
SECTION: NATIONAL/INTERNATIONAL PAGE: A/1 EDITION: EVENING
SOURCE: Associated Press
DATELINE: WASHINGTON LENGTH: Medium
Dr. Solomon Snyder of Johns Hopkins School of Medicine in Baltimore said his research team used tissue removed from a child during brain surgery to develop a colony of human brain cells that divide and grow in laboratory dishes.
Never before, Snyder said, have scientists been able to coax human brain cells into growing and reproducing in a laboratory. But the new cell line can now be expanded at will through thousands upon thousands of generations, he said.
Asked why the brain cells taken from the child were able to divide and grow in the laboratory when so many similar, earlier efforts had failed, Snyder had no answer.
"They clearly had an intrinsic potential to divide more than conventional neurons," he said in a telephone interview. "Just why, we simply don't know."
Other researchers called the discovery one of "tremendous significance" that may cause an explosion of new research and treatment in brain diseases.
Although brain cell transplantation is the eventual goal, Snyder said it will take years of laboratory studies before the brain cells can be used on human patients.
A report on the research is published in today's edition of the journal Science.
Scientists have long been hampered in their study of the brain because human brain cells won't reproduce. Except for very limited exceptions in isolated areas of the brain, humans at birth have all the brain cells they will ever have.
If a substantial number of brain cells are damaged by disease, injury or stroke, functions controlled by those cells are lost forever.
Snyder said the cultured cells underwent 3 1/2 years of vigorous testing to assure they aren't an abnormal growth such as cancer, but are, in fact, normal brain cells.
"We have every confidence that they will function that way when transplanted," he said. "If they were placed into the environment of the brain, we would expect them to be functional."
Brains damaged by degenerative diseases such as Alzheimer's, or by stroke or trauma, may one day be repaired by transplanting cells grown in the Hopkins lab, Snyder said.
"That's what we're working on," he said. "That is our full intent."
The cells that founded the culture were taken from the brain of an 18-month-old girl who underwent surgery in 1986.
The young patient was suffering from seizures and doctors determined that one side of her brain had grown more than the other. Surgeons removed excess brain tissue to correct the condition.
Snyder said one of his students immediately placed about a gram of brain tissue into a culture medium.
Two small clusters of cells in the specimen survived after 21 days. Researchers treated those cells with hormones to force them to mature and develop into normal neurons.
As far as can be determined, Snyder said, the brain cells are normal neurons, except they can divide and multiply.
"If you put them into a hole in the head, they would grow until they fill the head and then just stop," he said.
Barbara Bregman, a brain researcher at Georgetown University here, said it was premature to suggest that the cell line could eventually be used for brain tissue transplants. But she said the fact that a living culture of human brain cells has been developed "is very valuable and exciting" and will enable scientists to conduct brain experiments not possible before.
Dr. John Sladek, chairman of neurobiology at the University of Rochester School of Medicine, said the Hopkins research is "of tremendous significance."
If further study confirms that the cells are normal neurons, he said, there is a "real possibility" of one day using the culture for brain cell transplants in humans.
by CNB