Los Angeles, Calif., Feb 14, 2008 / 01:28 am
U.S. scientists have reprogrammed human skin cells into cells with characteristics similar to those of embryonic stem cells, confirming the breakthrough discovery made by a Japanese researcher, according to news reports.
Stem cells are considered to have significant potential for medical treatments including tissue regrowth and transplants. While some stem cells can be extracted from adult tissue, others are produced through the controversial process of cloning human embryos and destroying them to harvest their cells. Embryonic stem cells have the ability to become every cell type found in the human body.
Scientists at the University of California at Los Angeles genetically altered human skin cells using four regulator genes, publishing their findings in the February 11 edition of Proceedings of the National Academy of the Sciences.
Their process produced what are called induced pluripotent cells, or IPS cells, that are almost identical to human embryonic stem cells in function and biological structure.
The lead author of the study was Kathrin Plath, an assistant professor of biological chemistry and a researcher with the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research. She described the research in a prepared statement.
"Our reprogrammed human skin cells were virtually indistinguishable from human embryonic stem cells," she said. "Our findings are an important step towards manipulating differentiated human cells to generate an unlimited supply of patient specific pluripotent stem cells. We are very excited about the potential implications."
The UCLA research confirms the similar work of researchers Shinya Yamakana at Kyoto University and James Thomson at the University of Wisconsin. Plath said the studies demonstrate human IPS cells can be easily created by different laboratories and could mark a milestone in stem cell-based regenerative medicine.
The new technique could replace a stem cell harvesting method called somatic cell nuclear transfer (SCNT), sometimes called therapeutic cloning. At present, therapeutic cloning has not been successful in humans.
The first study author William Lowry, assistant professor of molecular, cell, and developmental biology, also addressed the findings in a statement.
"Reprogramming normal human cells into cells with identical properties to those in embryonic stem cells without SCNT may have important therapeutic ramifications and provide us with another valuable method to develop human stem cell lines," he said.
Like other prominent stem cell researchers, Lowry claimed that embryonic stem cell research was still necessary.
"It is important to remember that our research does not eliminate the need for embryo-based human embryonic stem cell research, but rather provides another avenue of worthwhile investigation," he said.