FT. LAUDERDALE, FL (Reuters Health) Feb 20 - Neural progenitor cells differentiate into mature neurons and glia after transplantation into normal and stroke-affected brains of rats, Dr. Daniel M. Rosenbaum told an audience at the 26th International Stroke Meeting of the American Heart Association.
But stem cell transplantation for stroke may be more than a decade away, Dr. Rosenbaum told Reuters Health. "All we are able to show right now is that these cells are functional and secrete different neurotransmitters — we have yet to show if there is functional recovery," he stressed.
"The ultimate fantasy," he said, "is that when someone comes in with a stroke, you do a limited biopsy, take out some of the progenitor cells, and then expand them in tissue culture [to] transplant them back into the brain."
Dr. Rosenbaum and colleagues from the Albert Einstein College of Medicine in New York obtained neural progenitor cells from rat embryonic cortex and transplanted them into normal rat brain. "We also did this to a group of animals that were subjected to stroke," Dr. Rosenbaum said.
In normal rats, progenitor cells transplanted into the cerebral cortex did best in terms of proliferation and differentiation, he reported. "If you injected them into the deeper regions of the brain, there was some survival, but not nearly as much as when the cells were transplanted into the cortex," he explained.
"Conversely, when we transplanted the cells into the cortex of stroke brains, the cells did not proliferate nearly as much as when they were transplanted into the deeper structures of the brain," Dr. Rosenbaum said.
This finding suggests,
the researchers say in a meeting abstract, "that local environmental factors
differentially regulate the profile of progenitor cell regenerative responses
to central nervous system injury."
2000 Reuters Ltd.