MINNEAPOLIS, April 25 (UPI) -- Research conducted on mice and released Friday reveals that a rare type of adult stem cell derived from bone marrow could grow into any of the major cell types of the brain.
The finding is the first of its kind and increases the possibility that these cells one day could be used to treat brain disorders such as Parkinson's and multiple sclerosis.
"This adult stem cell has the capability of becoming pretty much any kind of nerve cell if it is exposed to appropriate developmental cues," Walter Low, with the University of Minnesota Medical School's department of neurosurgery and the study's principal investigator, told United Press International.
Referring to the potential applications of this research, Low said: "We could take these adult stem cells and under the right conditions develop them into dopamine-producing cells for treating Parkinson's or myelin-producing cells that could be used to treat multiple sclerosis."
He added: "Any type of neurological disorder could be treated if it is based on the loss of a particular type of cell."
The study, which appears in the April 25 issue of the journal Cell Transplantation, is an extension of a study Low's team conducted last June, in which they showed how rare stem cells -- called multipotent adult progenitor cells -- could become virtually every cell type within the body.
In the current study, Low's group took those same stem cells from a strain of mice that produced a special protein and injected the cells into a developing mouse embryo. The goal was to get a better look at what these cells become in the brain. The embryos then were implanted into a female and allowed to develop naturally.
Using antibodies that bind to the special protein, the researchers were able to identify brain cells that originated from the stem cells throughout all the areas of the brain in the resultant mice offspring.
"The adult stem cell could generate (various brain cells, including) neurons, glial cells and astrocytes," Low said.
His team also looked at areas of the brain involved in Parkinson's and found the stem cells gave rise to cells that produced dopamine, which typically die out in that disease.
The stem cells also produced cells that generate a chemical called GABA, which could be useful in treating Huntington's disease.
The behavior of the mice was completely normal, indicating the brain cells produced from the stem cells are functional, Low said.
However, some scientists stressed the need for tempered enthusiasm in interpreting the results.
The findings are "very encouraging and further demonstrates the plasticity of these cells," Dr. Robert Lanza, vice president of medical and scientific development at Advanced Cell Technology, which is developing embryonic stem cells as treatments for various diseases, told UPI.
Lanza noted: "It's very important not to overinterpret these data" and jump to unsubstantiated conclusions about the clinical use of these cells.
Lanza's company has performed similar experiments with cow embryonic stem cells and found the cells, when implanted into developing cow embryos, could become all the different cell types of the body. But they have tried for several years -- without success -- to get the stem cells to become different cell types in test tubes, as would be required to use the cells to treat disease in humans.
So simply getting the stem cells to generate different cell types by implantation into the embryo might mean very little in terms of being able to use the cells to cure disorders, Lanza said.
Low agreed figuring out how to coax the cells to become various cell types in the laboratory setting would be a challenge. If the aim was to treat disease, another barrier would be uncovering methods to increase the numbers of the rare cells in the lab, he said.
Low's group already is working on techniques to scale up production of the cells. "I think it will be doable," he predicted.
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(Reported by Steve Mitchell, UPI Medical Correspondent, in Washington.)
