SAN DIEGO - San Diego's large stem cell research community has
been fixated on Tuesday's startling announcements that human
embryonic stem cells have apparently been grown from skin
Researchers say their work will get easier as a result of the
findings, which were made by two separate teams of scientists, in
Japan and Wisconsin. They also expect fewer troubles with patents,
which have plagued the new science. But years of work remains to
benefit the sick. And the thorny ethical debate over embryonic stem
cell research won't go away, they say.
"Excitement" is the most common reaction, said Larry Goldstein,
head of UC San Diego's stem cell research program. "Walking through
the labs and bumping into people - they're all reading the
(scientific) paper," Goldstein said.
Embryonic stem cells are the "ancestral" cells that give rise to
nearly all the cell types in the body. Researchers are trying to
turn cells into replacement cells to treat diseases or
Both the Japanese and Wisconsin teams transformed the skin cells
by inserting genes that "reprogrammed" skin cells to act like
embryonic stem cells. The research teams delivered the genes
through "retroviruses" that insert their genes into the cell
nucleus and are passed down to future generations of cells. The
Japanese team used facial cells; the Wisconsin team used foreskin
cells from a newborn baby.
Producing stem cells from skin cells already has been performed
in other mammals, said Fred "Rusty" Gage, a noted researcher at the
Salk Institute, who is also studying stem cells.
"We were waiting for this to come through," Gage said. He and
Goldstein are interested in turning skin cells from Alzheimer's
patients into brain cells, and study whether (and how) they develop
signs of the disease.
"It's very important that it was demonstrated in two separate
laboratories using slightly different techniques. It gives you a
lot of confidence in its validity," Gage said.
"The major caution is that these cells are harboring
retroviruses now, so their use for transplantation is off the
table" because the retroviruses could cause diseases, Gage said. He
is working on a different approach, by activating the transforming
genes, which are present in skin cells, but turned off.
Lowering patent barriers
Gage and Goldstein said there should be fewer patent barriers to
using the new approach than the original method of growing
embryonic stem cells directly from human embryos. Patents for that
method are held by the Wisconsin Alumni Research Foundation, which
has repeatedly asserted its right to enforce the patents.
Gage said he didn't think the genes used by the two research
teams were covered by the Wisconsin patents. Goldstein said any
patents on the new methods would probably be less intrusive than
the old ones. To get cells grown by the Wisconsin methods,
researchers generally have to sign restrictive licenses, he said.
The new method allows researchers to grow their own cells.
"If you have more control over the materials themselves, it
really simplifies things," Goldstein said. "I'm hoping that
everybody learned from the patent mess with the original embryonic
stem cells. Intellectual property is very important for getting
private investment and for commercializing."