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ReutersWASHINGTON (Reuters) - Researchers trying to find ways to transform ordinary skin cells into powerful stem cells said on Sunday they found a shortcut by "sprinkling" a chemical onto the cells.
Adding the chemical allowed the team at the Harvard Stem Cell Institute in Massachusetts to use just two genes to transform ordinary human skin cells into more powerful induced pluripotent stem cells or iPS cells.
"This study demonstrates there's a possibility that instead of using genes and viruses to reprogram cells, one can use chemicals," said Dr. Doug Melton, who directed the study published in the journal Nature Biotechnology.
Melton said Danwei Huangfu, a postdoctoral researcher in his lab, developed the new method.
"The exciting thing about Danwei's work is you can see for the first time that you could sprinkle chemicals on cells and make stem cells," Melton, a Howard Hughes Medical Institute Investigator, said in a statement.
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Huangfu tried treating the cells first with valproic acid. After she did this, it only took two of the four usual genes to reprogram the cells into iPS cells, she reported.
This is good because the other two genes usually needed can promote cancer.
The Melton team used retroviruses to carry the two genes in but suggest they might not be necessary.
"These results support the possibility of reprogramming through purely chemical means, which would make therapeutic use of reprogrammed cells safer and more practical," they wrote in their report.
Huangfu said the valproic acid unraveled the chromatin -- the physical structure of the chromosomes -- making it possible to get in and alter the DNA more easily.
"We may need two types of chemicals, one to loosen the chromatin structure, and one to reprogram. We are looking for that reprogramming chemical, and it should be possible to find it eventually," she said.
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