Scientists have known for some time that several genes can reprogram a cell back to a state in which it can become any type of cell – like an embryonic stem cell can. However, these genes can cause cancer, a real safety stumbling block to their use. And according to researchers at the Whitehead Institute for Biomedical Research in Massachusetts, they may interact with thousands of other genes in the cell, yielding unpredictable results.
Now thanks to work being done by Whitehouse Institute researchers, for the first time, potential cancer-causing genes from induced pluripotent stem cells (iPS cells) have been removed and those iPS cells have been turned into brain cells involved in Parkinson’s disease. Because the iPS cells can be made from a patient’s own skin cells, the chances for rejection are reduced. This has opened up the long-term possibility of transplanting health cells made from iPS cells to replace those cells damaged by disease or injury. However, Whitehead Institute researcher Dirk Hockemeyer says that a more immediate use for iPS cells may be in “lab dishes testing the effects of new drugs.”
To remove the potential cancer-causing genes, the Whitehouse Institute researchers used viruses to “transfer three genes into the skin cells of Parkinson’s patients, then removed them after they had done their job.” The resulting cells looked like “embryonic stem cells from Parkinson’s patients, without the extra genes.” Those cells were used to create dopamine-producing nerve cells – the cells that are known to die in patients with Parkinson’s, causing such symptoms as tremors, slow movement and balance problems.
“Other labs have reprogrammed mouse cells and removed the reprogramming genes, but it was incredibly inefficient, and they couldn’t get it to work in human cells,” says Whitehead Institute scientist Rudolf Jaenisch. “We have done it much more efficiently, in human cells, and made reprogrammed, gene-free cells.”
News Release: Scientists remove cancer genes from stem cells www.newsdaily.com March 5, 2009
