(article by Jason Mick at DailyTech)
DailyTech has long
covered developments in stem cell research — everything from using the
stem cells in practical medical research to creation printable blood vessels to using the cells in more outlandish experiments such as the human-sheep “chimaera,” which sounds like something straight out of The Island of Dr. Moreau.
Most importantly new research allowed for the creation of pseudo-stem-cells from somatic (differentiated) cells,
via an induction process. The research was first pioneered by Japanese
scientists and later confirmed by American researchers at Whitehead
Medical Center in Massachusetts. This new non-embryonic technique has
the reluctant blessing of traditional stem cell opponents, including
U.S. President George W. Bush and the Catholic Church.
The cells are dubbed induced Pluripotent Stem cells, iPS cells for
short. Last month it was shown that the cells could be created as
easily from human skin tissue as mouse skin tissue. Further, the
research showed that the iPS cells behaved like true stem cells and
could differentiate into the more than 200 types of cells in the human
Now scientists have completed groundbreaking research
which gives an exciting glimpse into the tremendous potential the
synthetic creation of stem cells can hold. Researchers at Whitehead
have used the artificially created stem cells, created from mouse skin
tissue, to cure mice of sickle cell anemia, a potentially fatal
inherited disease. The research is published in the journal Science and is titled “Treatment of Sickle Cell Anemia Mouse Model with iPS Cells Generated from Autologous Skin.”
The research sounds so good that many might wonder why the
scientists at Whitehead are not rushing to put the process to work
curing human disease. The reason for Whitehead’s reluctance is that
they are trying to change aspects of their creation approach in order
to make it human safe. Researchers currently utilize genetically
modified viruses in the induction process. The viruses have the
potential to trigger tumor growth in healthy mammalian tissues.
“The big issue is how to replace these viruses”, commented Rudolf Jaenisch co-leader of the research at Whitehead, in an interview with the Washington Post.
The current treatment method uses multiple rounds of viruses to modify
genetic behavior of the cells. The first round of gene-modified
viruses induces the cells to behave like stem cells. Next the
scientists used a gene splicing technique to snip out the undesirable
sickle-cell gene and replace it with a healthy gene. Finally the
scientists used an additional round of viruses which induced the cell
to develop into a bone marrow cell.
The marrow cells were injected into the mice with sickle-cell and
anchored in the bone marrow and began to release healthy red blood
“All the parameters we can measure are now normal,” Jaenisch enthused. “The mice are cured.”
Hopefully the researchers can modify the technique to avoid tumor
induction as the potential of curing sickle-cell disease would help
save many human lives. In humans sometimes sickle cell is treated by a
bone marrow transplant, but only 20% of humans have a donor close
enough to them to allow for a safe transplant. And over 20% of those
who do receive transplants experience failure, often resulting in
death. However, bone marrow created from a modified version of this
process would be completely safe as the cells are genetically identical
to the donor.
In the mice radiation was used to kill the bone marrow of the mice, but
in humans chemotherapy drugs such as Idarubicin and Cytarabin can be
used to kill the bone marrow in a less caustic manner. In mice 80
percent of the marrow cells now are the genetically healthy cells and
they have experienced no tumor growth.
George Q. Daley, a stem cell researcher at Children’s Hospital in
Boston, said the test was proof that human clinical applications of iPS
cells were feasible. He said, “There will be lots of unanticipated
setbacks before we end up in the
clinic, but this work suggests that we will ultimately get there.”
Jaenisch surprised some by emphasizing that despite his group’s
success, research on embryonic stem cells should be pushed ahead, not
“All the progress in this field was only possible because we had
embryonic stem cells to work with first. We need to
make more ES cells and really define which are going to be the best
ones for different applications,” he said.
Regardless, for stem cell proponents and opponents alike, this new
research demonstrates a exciting process that may someday hold the cure
for human diseases such as sickle-cell anemia, Parkinson’s Disease and
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