CHICAGO, Nov 20: Two groups of scientists have successfully transformed human skin cells into stem cells, potentially granting unlimited access to the foundation cells which can replace diseased or damaged tissues and organs, it was announced on Tuesday.
This new technique, once perfected, could eventually allow doctors to create stem cells with a specific patient’s genetic code, eliminating the risk of rejection.
It could also rapidly advance research in the treatment of cancer, Alzheimer’s and Parkinson’s diseases, diabetes, arthritis, spinal cord injuries, strokes, burns and heart disease because scientists will have much greater access to stem cells.
Stem cells are seen as a possible magic bullet for some of the most deadly and debilitating diseases.
That’s because the essentially blank cells can be developed into any of the 220 types of cells in the human body.
But access to stem cells in the United States – even for research purposes – has been limited because of ethical concerns over the use of human embryos and embryonic cloning.
And stem cells derived from embryos, like transplanted organs, carry the risk of rejection by patients.
“The induced cells do all the things embryonic stem cells do,” said study author James Thomson of the University of Wisconsin at Madison, who first coaxed stem cells from human embryos in 1998.
“It’s going to completely change the field.” The simultaneous discoveries by researchers in Japan and the United States were heralded as “monumental”.
“(The) work is monumental in its importance to the field of stem cell science and its potential impact on our ability to accelerate the benefits of this technology to the bedside,” said Deepak Srivastava, director of the Gladstone Institute of Cardiovascular Disease.
“Not only does this discovery enable more research, it offers a new pathway to apply the benefits of stem cells to human disease.”
Both teams of researchers were able to transform the skin cells by using a retrovirus to insert four different genes into the cells.
The Japanese team, led by Shinya Yamanaka of Kyoto University, managed to produce one stem cell line out of every 5,000 cells.
“This efficiency may sound very low, but it means that from one experiment, with a single 10 centimeter dish, you can get multiple iPS (induced pluripotent stem) cell lines,” he said, referring to a stem cell type capable of creating any type of cell in the body except, possibly, those of the placenta.
The US team, led by Thomson, reprogrammed one of every 10,000 cells but did so without the use of a gene that is known to cause cancer.
Both techniques have the risk of mutation because the cells retained copies of the virus used to deliver the genes.
The crucial next step, according to an article in Science magazine, is to find a way to switch on the genes that cause the skin cells to regress into stem cells rather than relying on the retrovirus to insert the genes.
“It’s almost inconceivable at the pace this science is moving that we won’t find a way to do this,” stem cell researcher Douglas Melton of Harvard University told Science magazine.
The ability to design patient and disease-specific stem cells ought to help push research forward even before the mutation risk is eliminated.—AFP