MONDAY, Feb. 11 (HealthDay News) -- U.S. scientists say they've
reprogrammed human skin cells into ones with the same blank-slate
properties as embryonic stem cells, a breakthrough that could aid
in treating many diseases while sidestepping controversy.
Human embryonic stem cells have the ability to become every cell
type found in the human body. Being able to create these cells en
masse and without using human eggs or embryos could generate a
potentially limitless source of immune-compatible cells for tissue
engineering and transplantation medicine, said the scientists, from
the University of California, Los Angeles.
The researchers genetically altered human skin cells using four
regulator genes, according to findings published online in the Feb.
11 edition of the journal
Proceedings of the National Academy of the Sciences.
The result produced cells called induced pluripotent stem cells,
or iPS cells, that are almost identical to human embryonic stem
cells in function and biological structure. The reprogrammed cells
also expressed the same genes and could be coaxed into giving rise
to the same cell types as human embryonic stem cells, the
researchers said.
"Our reprogrammed human skin cells were virtually
indistinguishable from human embryonic stem cells," lead author
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, said in a prepared statement. "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 findings confirm similar work first reported in late
November by researcher Shinya Yamanaka at Kyoto University and
James Thompson at the University of Wisconsin. Together, the
studies demonstrate that human iPS cells can be easily created by
different laboratories and are likely to mark a milestone in stem
cell-based regenerative medicine, Plath said.
Reprogramming adult stem cells into embryonic stem cells has
significant implications for disease treatment. A patient's skin
cells, for example, could be reprogrammed into embryonic stem cells
that could be prodded into becoming beta islet cells to treat
diabetes, hematopoetic cells to create a new blood supply for a
leukemia patient, or motor neuron cells to treat Parkinson's
disease, the researchers said.
These new techniques to develop stem cells could potentially
replace a controversial method to reprogram cells called somatic
cell nuclear transfer (SCNT), sometimes referred to as therapeutic
cloning. To date, therapeutic cloning has not been successful in
humans.
"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," study first
author William Lowry, an assistant professor of molecular, cell and
developmental biology, said in a prepared statement. "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."
However, top stem cell scientists worldwide stress further
research comparing reprogrammed cells with stem cells derived from
embryos -- considered the gold standard -- is necessary.
More information
The U.S. National Institutes of Health has more about
stem cells.
