MONDAY, March 28, 2005 (HealthDayNews) -- In the future, stem cell therapy could be just a pluck away, new research suggests.
Stem cells found in mouse hair follicles can develop into brain cells and other cell types, researchers report. The finding suggests human hair follicles may be an effective, accessible locale in which to harvest these regenerative cells.
Stem cells have the potential to develop into any cell type, including heart, brain and muscle cells. The hope of scientists is that one day stem cells will help treat Alzheimer's, heart failure and other conditions linked to excessive cell death.
"We had previously found that the stem cells that make the hair follicles have similar features to stem cells that make the brain," said lead researcher Robert M. Hoffman, who is also chairman of the board of the San Diego-based research company AntiCancer, Inc.
In the current study, Hoffman's team was able to isolate stem cells from hair follicles and coax them in to becoming neurons -- brain cells -- and other types of cells, including muscle cells.
In experiments with mice, the researchers isolated and cultured whisker stem cells from what's known as the "bulge area" of the whisker follicle. After one week, the cells became neurons and other neural cells. After several more weeks and months, the stem cells differentiated into skin cells, smooth muscle cells, and skin-color-producing cells, the researchers said.
In addition, when the stem cells were transplanted under the skin of mice, they matured into neurons, according to the report, published in the March 28 early edition of Proceedings of the National Academy of Sciences.
"Hair follicle stem cells might be sufficiently plastic that they can make other cells under human direction, and be used for therapeutic purposes," Hoffman speculated.
Hoffman believes the importance of this discovery is that it will make stem cells easier to obtain. "Plucking a hair follicle, as opposed to digging out bone marrow, digging out cells in the brain -- the access is the real potential advantage," he said.
"You don't have any political problems, either, like you would using embryonic stem cells," Hoffman said.
Much remains to be done, Hoffman stressed. His team is working on growing large numbers of cells from hair stem cells and seeing how easily they can be differentiated into different cell types.
"These are exciting findings that contribute new evidence that primitive stem cells are present at many sites in postnatal tissue," said Deryl Troyer, a professor in the department of anatomy and physiology at Kansas State University.
Troyer believes that these mouse experiments may be relevant to humans. "Although this work was done in mice, it seems likely stem cells with similar potential are present in human hair follicles, and thus could be induced to become neurons or glia [another type of brain cell] outside the body," he said.
If this can be done, stem cells from human hair may have therapeutic applications for a variety of neurodegenerative diseases, and they could be transplanted back into the same person from which they were derived, avoiding immune rejection of the cells, Troyer said. "More work needs to be done, however, to show that they possess all of the functional characteristics of neural cells," he said.
However, another expert said she had problems with Hoffman's findings.
Dr. Eva Mezey, an investigator from the National Institute of Neurological Disorders and Stroke, said the differences between mouse and human hair follicles are substantial, and what is true for mice may not be so in humans. In addition, Mezey said that earlier experiments had already found stem cell in hair follicles.
"I was not impressed by the quality of the paper," Mezey said. "But it does not mean that they are wrong. I do believe in plasticity, so it would not be a surprise if these stem cells could become neural cells, given the right environmental cues."
The National Institutes of Health can tell you more about stem cells.