New Success in Making Stem Cells
Scientists Turn Ordinary Cells From Mice Into Stem Cells
June 6, 2007 -- Scientists today announced that they have coaxed normal
cells from mice into embryonic-like stem cells.
If the strategy works in human cells, doctors may one day be able to tweak a
patient's cells as part of stem cell therapy.
Stem cells can develop into different types of cells. Embryonic stem cells
have a wider range of possibilities than adult stem cells.
Most cells in the adult body aren't stem cells. They ordinarily can't become
stem cells or any other type of cell. For instance, a skin cell stays a skin
cell for its entire life cycle; it can't become a stem cell, a heart cell, or
any other type of cell.
But a new stem cell study shows that it's possible to break that rule -- at
least, in mice.
New Stem Cell Study
The researchers included Kathrin Plath, PhD, and Konrad Hochedlinger, PhD.
Plath works at the University of California, Los Angeles (UCLA). Hochedlinger
works at the Massachusetts General Hospital Cancer Center and Harvard Stem Cell
Institute in Boston.
They conducted a series of lab tests on normal mouse tissue cells called
fibroblasts. The scientists exposed the fibroblasts to four chemicals called
Oct4, Sox2, c-Myc, and Klf4.
Those four chemicals turned the fibroblasts into stem cells that were
"remarkably similar" to embryonic stem cells, write the
The stem cells made from the fibroblasts were "virtually
indistinguishable from embryonic stem cells," Plath says in a UCLA news
release. "We could find no evidence that they were different in any way. We
were rather surprised at how well this reprogramming worked."
Plath and colleagues are trying the same strategy on human cells; that work
may take years, says the UCLA news release.
Shinya Yamanaka, MD, PhD, of the stem cell biology department at Japan's
Kyoto University, reviewed the new study.
Yamanaka was one of the Japanese experts who first reported that the four
chemicals might turn ordinary cells into stem cells.
Yamanaka notes the potential shown in the new study. He also points out that
other methods are also being tested and that all of those methods have possible
risks, including promoting tumors.
The study and Yamanaka's review appear in the inaugural edition of the
journal Cell Stem Cell.