|Researchers Find Shortcut to Generating Brain Stem Cells|
Scientists at the Life & Brain Research Center at the University of Bonn, Germany, have succeeded in generating brain stem cells directly from the connective tissue of mice. These stem cells can reproduce and be converted into various types of brain cells.
To date, only reprogramming in brain cells that were fully developed or had only a limited ability to divide was possible.
The new reprogramming method, published in the current edition of Cell Stem Cell, builds on work by Japanese researcher Shinya Yamanaka and his team, who produced stem cells from the connective tissue cells of mice for the first time in 2006.
The Bonn research team was led by Dr. Frank Edenhofer and included colleagues at the university's Institute of Reconstructive Neurobiology and the Institute of Human Genetics. They used connective tissue cells from mice as a starting material and, just as Yamanaka did, initiated the conversion with a combination of four genes. But this time the goal was to produce neural stem cells (brain stem cells) rather than pluripotent (iPS) cells, as Yamanaka did.
The gene "Oct4" was critical to the reprogramming. "Oct4 activates the process, destabilizes the cells and clears them for the direct reprogramming. However, we still need to analyze the exact mechanism of the cellular conversion," Dr. Edenhofer said.
The researchers reported that their reprogramming method was up to three times faster than the method used to produce the iPS cells, since they were able to cut down on the reprogramming of the cells via the embryonic stage. This consequently reduced the work involved and cost as well. In addition, the Bonn method is associated with a dramatically lower risk of tumors and results in a nearly limitless number of neural cells, the researchers say.
"Our work could form the basis for providing practically unlimited quantities of the patient's own cells," Dr. Edenhofer added.
The next step is to determine whether the results can be applied to humans.