No not trying to make that point. As for embryonic stem cell research, I think it is a very short term problem. Science will quickly advance past the point where we will need it - that is if we aren't there already:
Hard Cell
Science doesn't need subsidized
embryo research.
BY RICHARD MINITER
Monday, July 23, 2001 12:01 a.m. EDT
When President Bush meets the pope today, one of the
issues they're sure to discuss is the controversy over
embryonic stem-cell research. Mr. Bush is reportedly
struggling with the decision of whether to accept a
last-minute Clinton decision that would effectively lift the
ban on federal funding of such research. During his campaign,
Mr. Bush promised to uphold the ban.
Proponents of such research, and the media, frame the issue
as one of religion vs. science, arguing that if the president
keeps his promise, he will set back new medical advances
and sacrifice potential cures for diseases like Parkinson's.
But science isn't on their side, and Mr. Bush doesn't have to
choose between convictions and cures. While federal funding
for embryo research is banned, the research itself is not. The
private sector lavishly funds research on stem cells drawn
from both embryos and adults. Yet research on embryonic
stem cells is no more developed than the embryos
themselves--while research on adult stem cells is close to
delivering miraculous treatments.
Consider these recent advances:
• Surgeons in Taiwan restored vision to patients with severe
eye damage by using stem cells from the patients' own eyes.
Their vision improved from 20/112 to 20/45, according to
results published in the New England Journal of Medicine.
• British scientists found that adult stem cells in bone marrow
can turn into liver tissue, a first step toward developing new
treatments for liver damage. Their work was reported in the
journal Nature.
• Two recent studies show that adult stem cells in bone
marrow transplanted into the brain of mice can develop into
neurons and have been reprogrammed into healthy brain cells
in lab rats. Previous research had shown this transformation
was possible in cultured cells, but these studies, one of
which was published in the journal Science, show it can
happen in living animals.
• Scientists found that adult stem cells in bone marrow
injected into a damaged mouse heart could become
functional heart muscle cells, and that these new cells
partially restored the heart's pumping ability. One of the
scientists predicted that after successful follow-up studies,
human clinical trials could start in three years. The results
were published in Nature.
These findings were all reported within the past year. And
they are only a few examples of the breathtaking medical
breakthroughs occurring after years of research on adult
stem cells--stroke victims' brains repaired with adult stem
cells becoming fully functional neurons connecting with
existing brain cells, new cartilage grown to repair damaged
knees.
We are on the verge of astounding human applications using
adult stem cells. Embryonic stem cells, by contrast, have yet
to save a single life.
Stem cells are unspecialized cells that have the ability to
transform themselves, in varying degrees, into many other
types of cells. Thus a single stem cell could become a skin
cell, a hair cell, a liver cell and so on. All of us were once
stem cells, and our bodies still hold many forms of these
cells.
It appears that every organ and tissue in the body has
undifferentiated stem cells. These cells may exist to repair
organs when they are traumatized or damaged, but scientists
are still puzzled by how they work and what exactly they are
supposed to do. If scientists can improve this natural repair
process with adult stem cells, people may be able to grow
new livers from stem cells extracted from their own liver.
Another source of adult stem cells is body fat. And umbilical
cords provide a large supply of stem cells--without political
or moral controversy.
A National Institutes of Health report, released just in time
for last week's congressional hearings, argues that stem cells
from embryos are better. But on closer examination, the
evidence is shaky and speculative, while the unique
drawbacks of embryo stem cells are becoming clearer.
The case for the superiority of embryo stem cells rests on
three pillars: They are easier to harvest, there are more stem
cells in embryos than in adults, and they can be more easily
changed into every organ and tissue in the body.
The first two claims are misleading. Harvesting is a
nonproblem. Scientists have been extracting some types of
human adult stem cells for almost a decade, while human
embryo stem cells weren't successfully isolated until 1998.
Several biotech companies have developed proprietary
methods to make adult-cell isolation and extraction even
easier. "We've been here in the background while all the
noise was going on, and there's been a pressure on us to
provide a solution," John Wong, CEO of MorphoGen
Pharmaceuticals, told BioWorld Today last August. "We
believe we've provided that solution. The technology has just
moved beyond stem cells from embryonic tissue."
While it's true that embryos have a higher ratio of stem to
nonstem cells, that doesn't mean much. Scientists have
discovered stem cells in adults in virtually every major organ,
including the brain and body, and researchers last year
identified conditions that would allow for the multiplication of
adult stem cells in culture by a billion-fold in a few weeks.
The real argument for using stem cells from embryos is they
are more "plastic"--that is, they are easier to change into
other types of cells. This is a hard claim to evaluate
because, as last week's NIH report notes, "the field of
stem-cell biology is advancing at an incredible pace with new
discoveries being reported in the scientific literature on a
weekly basis." Any distinguishing advantage from using
embryo stem cells today may already have been overtaken
by a lab that is waiting for its results to be published.
Indeed, scientists have already proved adept at turning adult
stem cells into a variety of seemingly unrelated cells. Jonas
Frisen, a scientist working at NeuroNova AB, a
Stockholm-based biotech firm, published some exciting work
in one of the world's leading scientific journals, Science, in
June 2000. "We have demonstrated that the potency of
these [adult stem] cells was far greater than expected and
what seemed to be a fairly restricted cell type can give rise
to many different types of cells. These recent findings may
turn some previous concepts upside down," Dr. Frisen said in
a press release. Already, human adult stem cells have been
transformed into cartilage, muscle, bone, cardiac tissues,
neural cells, liver tissues and blood vessels. Research with
animal adult stem cells indicate the ability to transform them
into kidney, heart, lung, intestine and nervous-system
tissues.
While adult stem cells may never be as completely "plastic"
as embryo stem cells they will almost certainly be plastic
enough for all practical applications. "These adult tissues
don't appear to be as restricted in their fate as we thought
they were," Dennis Steindler, a professor of neuroscience and
neurosurgery at the University of Tennessee-Memphis, told
Blood Weekly magazine in May. "In some ways they may not
have the same potential as embryonic cells, but once we
figure out their molecular genetics, we should be able to coax
them into becoming almost anything we want them to be."
Diane Krause of the Yale School of Medicine--a supporter of
embryonic stem-cell research--says she was "surprised" by
her own research on adult stem cells. "It went against our
dogma," Dr. Krause says. Stem cells found in the liver were
believed to be limited to making liver tissue, stem cells in the
skin more skin and so on. "But at least for stem cells found in
bone marrow, that is not true." Scientists, who previously
underestimated the potential of adult stem cells, are
"searching for a new paradigm," she adds.
What's more, new research suggests that embryonic stem
cells may be a little too plastic. "The emerging truth in the
lab is that pluripotent [embryonic] stem cells are hard to rein
in," University of Pennsylvania bioethicist Glenn McGee told
MIT's Technology Review. "The potential that they would
explode into a cancerous mass after a stem-cell transplant
might turn out to be the Pandora's box of stem-cell
research." In a recent Weekly Standard article, author
Wesley J. Smith, who opposes embryonic stem-cell research
on moral grounds, cites a chilling report from China in a study
in the May 1996 edition of Neurology, the official journal of
the American Academy of Neurology, in which implanted
embryonic and fetal stem cells became bone, skin and hair
cells--inside a test subject's brain. He died.
Then there is the problem of rejection. Transplant patients
know that they must take antirejection drugs for years and,
in some cases, for life. New tissues developed from
embryonic stem cells may require a long-term regimen of
drugs to suppress the body's immune system. These drugs
have side effects, and a suppressed immune systems can
increase the risk of infection. This is not a problem of adult
stem cells because they can be drawn from the patient's own
body.
Adult stem cells appear to be easier to control than
embryonic cells, are closer to commercial application, and
have a history of proven benefits--including bone-marrow
applications.
It's easier to transform, say, a pancreatic adult stem cell into
pancreatic tissue than to turn an embryonic stem cell into
pancreatic tissue. "It is inherently a shorter biological step to
make a beta cell from a duct [adult stem] cell than it is from
other possible cells, such as embryonic stem cells," according
to the British Medical Journal. Human adult pancreatic stem
cells have already been grown in culture and differentiated
into insulin-producing cells.
Adult stem cells are also being used in human clinical trials
and applications to treat multiple sclerosis, leukemia, liver
disease, cardiac damage, brain tumors, ovarian cancer,
breast cancer, arthritis, lupus and other conditions. French
physicians used a patient's own adult muscle stem cells to
treat heart disease, with promising results.
Little wonder, then, that the private sector is focusing
almost exclusively on adult stem-cell research. Of the 15
U.S. biotech companies solely devoted to developing cures
using stem cells, only two focus on embryos. "While the
embryonic cells are rumored to have broad potential, so far
only adult stem cells have demonstrated wide uses," writes
Scott Gottlieb, a physician and staff writer for the British
Medical Journal, in The American Spectator.
In the race to cure Parkinson's disease, cancer and other
age-old scourges, the private sector is more than a few laps
ahead. And perhaps a dozen private-sector projects are
within a few years of human trials. StemCells Inc. is using
adult stem-cell research to develop methods for regenerating
damaged central nervous systems and restoring function to
kidneys and livers. Baltimore-based Osiris Therapeutic Inc.
has already developed technology for isolating adult stem
cells, found adult stem cells in the body's connective tissues
and conducted a clinical trial of adult stem-cell infusion for
breast cancer patients who'd had chemotherapy. "The
practical use of adult stem cells is not 10- to 15 years away
but well along in the commercialization process," Osiris
president James Burns told Transplant News in March 1999.
"We believe that adult stem cells will become a routine
treatment for cancer, immune disorders, orthopedic injuries,
transplant medicine, congestive heart failure and
degenerative diseases."
By contrast embryo stem-cell research is at the
drawing-board stage--not for lack of funds but for lack of
promising research to finance. Venture capitalists have no
agenda beyond making money; if they see embryo projects
that are likely to bear fruit over the next five to seven
years--the usual VC time horizon--they will fund them.
That the market is speaking so loudly against embryo
stem-cell research probably explains why embryo researchers
are so eager to reverse the ban on government funding. But
medical science will continue to advance even if Mr. Bush
keeps his word.
Whatever the president decides, though, the NIH should put
more funds into adult stem-cell research. That would give
the most promising research a big push--and isn't that what's
most important?
Mr. Miniter is an editorial page writer for The Wall Street
Journal Europe. His column appears Fridays.
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