Will stem cell funding decisions be based on the scientific evidence or
on what the media chooses to cover?
If this upsets you --- please call your Representative's and Senator's
office tomorrow and ask for them to co-sponsor H.CON.RES.17 (in the
House)
and S. 723 (in the Senate) in support of stem cell research funding.
Linda
Advances in Stem Cells, Cloning Renew Controversy
--- Scientists Say Embryo Research
Is Needed Despite Fat Finding
By Antonio Regalado
04/27/2001
The Wall Street Journal
Page B1
Grass-roots organizer Molly Naylor supports research into embryonic
stem cells, hoping that it may lead to a cure for the juvenile
diabetes that afflicts her son. But when she called the White House to
support stem-cell studies, she was surprised to hear that the
embryonic research might not be necessary.
She says the White House told her about a widely publicized study
showing that human fat may also contain stem cells.
From the beginning, science has collided with politics over stem-cell
research, which uses tissues derived from human embryos. But
supporters of stem-cell research are now concerned that science is
being bent for political ends. In missives being circulated on Capitol
Hill, anti-abortion activists are touting the fat report as evidence
that embryo research isn't needed. To scientists who support embryonic
research, the study, published in an obscure journal, seems largely
inconclusive.
Embryonic stem cells are capable of forming any type of human tissue,
a characteristic that has led the medical community to hail their
discovery as a once-in-a-century boon to transplant medicine. But to
obtain them, they must be harvested from embryos left over from
fertility treatments or early-stage aborted fetuses. Now, the need for
embryonic stem cells is being challenged by arguments -- including the
fat study -- that certain cells present in adults may possess similar
properties.
For opponents of embryonic stem-cell research, so-called adult stem
cells have become "the keystone in our public relations battle,"
according to Scott Weinberg, a spokesman for the American Life League.
The anti-abortion group has vigorously opposed research on embryonic
stem cells since they were first isolated in 1998, calling the work
illegal, immoral and unnecessary. With adult stem-cell studies winning
national media coverage, those talking points have gotten a major
boost. "It's really helping out," says a cheerful Mr. Weinberg.
For advocates of embryonic stem-cell research -- who include dozens of
Nobel Laureates and university presidents -- the play given to the fat
story is a worrisome sign that their cause could be losing momentum at
a critical juncture. Plans by the National Institutes of Health to
begin funding studies of embryonic stem cells are on hold. The Bush
administration is reviewing a decision reached last August by the
Department of Health and Human Services that the cells weren't covered
by a pre-existing ban on federal support for embryo research.
Critics allege that the fat study, which was published in the journal
Tissue Engineering, is being given far more weight than it deserves.
The authors of the paper, led by plastic surgeon Marc H. Hedrick of
the University of California, Los Angeles, showed that human fat
contained cells capable of giving rise to a variety of tissue types,
including bone and muscle. But because they started with a mixture of
cells, it remains unclear whether the effect was actually the work of
a fat stem cell or perhaps was due to contamination by bone-marrow
stem cells, which have been closely studied for more than a decade.
"If I said, `Point to the stem cell,' they wouldn't know what it is.
So they are not even close," says Harvard University embryologist Doug
Melton.
Although definitions vary, most scientists agree that a stem cell has
to meet two basic criteria: It must be able to reproduce itself, and
it must be able to make more than one type of specialized daughter
cell. Jeff Gimble, a research executive at Artecel Sciences Inc., a
biotechnology company based in Durham, N.C., says his company's work
on fat supports Dr. Hedrick's findings, but he doesn't believe that
fat tissue can meet the strictest scientific criteria for a stem cell.
But the story of getting useful cells from hated love handles quickly
took on a life of its own. "I knew it had the potential of being a
blockbuster story, but the press that we got went even beyond our
expectations," says Dan Page, the UCLA media-relations officer who
coordinated coverage that included segments on all three TV nightly
network newscasts.
Mr. Page says he and Dr. Hedrick were unaware that Albert Carnesale,
UCLA's chancellor, had just weeks earlier joined 111 other top
university officials in sending a letter to the Bush administration
cautioning that evidence for adult stem cells was in most cases
incomplete. The officials wrote that the evidence was far too
uncertain to be the basis for a sound policy decision.
Yet even as some research has come under fire, evidence is mounting
that certain adult cells are indeed able to turn into other types of
tissue. Studies have shown bone-marrow cells turning into liver, and
brain cells becoming blood. "The basic result, never mind the
politics, is that there is an astonishing plasticity in these cells,"
says Ron McKay, a biologist at the National Institutes of Health who
recently helped show that bone-marrow cells could repair the hearts of
mice. "Bone marrow is not supposed to regenerate heart, but here it is
doing it in a few days." And because a patient could be treated with
his or her own cells, in many cases adult stem cells may offer a
quicker route to practical treatment.
But Dr. McKay also notes that only the embryonic cell has been shown
to form all tissue types, and it is more easily grown in the lab,
another critical factor for developing cell-based treatments. Most
scientists believe both types of research hold promise, and both ought
to continue.
Advocates for embryonic stem-cell research hope that President Bush
will adopt that view. Writing today in the journal Science, California
Institute of Technology President David Baltimore and Stanford
University immunologist Irving Weissman again argue that adult stem
cells are largely unproven. According to Dr. Baltimore, "there is
tremendous pressure being put on those in power to adopt a narrow
religious view of when life begins. I don't think that is how we
should be making policy in the U.S."
It won't be an easy decision, and no one is more familiar with the
trade-offs than Dr. Hedrick, the author of the fat study. A practicing
Presbyterian, Dr. Hedrick describes himself as "very pro-life. I
believe abortion is wrong." Yet as a surgical fellow at the University
of California, San Francisco, he performed life-saving fetal surgeries
that in some cases used tissues from abortions. "It's a `greater good'
argument," says Dr. Hedrick. "I am uncomfortable using human fetal
tissue, but I have used it in the past to save a life."
---
Tissue Building Blocks
Stem cells have been indentified in a variety of human tissues,
including:
-- Embryo: Stem cells found here have the potential to form any
tissue in the human body
-- Bone marrow: `Hematopoetic' stem cells sustain the blood and
immune systems of adults
-- Nerves: Stem cells isolated from fetal and adult brains may one
day treat Parkinson's disease
-- Connective tissue: Scientists are studying cells capable of
forming bone, cartilage and muscle
-- Liver: Scientists are looking for the cell which accounts for the
liver's power of regeneration; could help those waiting for a
transplant
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