Norfolk,
VA (7/11/01)- Stem cell researchers find themselves in the media
klieg lights once again, following the release of a new study on harvesting
stem cells from embryonic human cells created specifically for that purpose.
This represents the latest phase in the growing debate between those favoring
stem cell research for the medical benefits it might bring versus those who
are strongly opposed on religious or moral grounds.
Right:
Culturing Human Embyronic Stem Cells click
to enlarge
The current uproar followed the release of a study in the journal Fertility
& Sterility by scientists at the Jones Institute for Reproductive
Medicine. The researchers reported success in creating new embryonic stem
cell lines using sperm and eggs donated for that purpose. This was accomplished
with private funding, since this practice is currently prohibited by federal
guidelines. Current guidelines proposed by the National Institutes for Health
would allow research involving human stem cells derived from human embryos,
but only when the cells are derived from frozen embryos that were created
for the purposes of fertility treatment, were in excess of clinical need,
and were obtained after the consent of the donating couple. The NIH Guidelines
also would prohibit the use of monetary inducements for the donation of the
embryo.
In the case of the present, privately supported, research, eggs and sperm
were provided by donors who were paid modest sums of money. Twelve donors
provided 162 eggs. One hundred and ten of these were fertilized successfully,
of which 50 matured to the blastocyst stage. The blastocysts yielded three
viable embryonic stem cell lines. (see illustration above)
"This research demonstrates the urgent need for federal oversight of stem
cell research, but federal oversight will only come hand-in-hand with federal
funding," said Lawrence Soler, Chairman of the Coalition for the Advancement
of Medical Research, a pro-research group.
|
"The job of the natural scientist is to make the
discoveries; that of the technologist to develop applications; and that
of the humanist is to suggest whether, how, and under what conditions
the work of the other two ought to be applied. "
Werner Heim, Biologist.
|
This is not the first time embryos have been created specifically for research
purposes. This goes back to early days of in-vitro fertilization research,
long before stem cells were part of the research picture. Moreover, the practice
is ongoing in other nations, notably the United Kingdom. UK researchers are
entitled to funding for research of this sort provided they follow clearly
established guidelines. Rather, the story is in the spotlight because it focuses
the bioethical issues now being debated in Washington, DC. President GW Bush
and Congress are coming come to terms with the regulation of stem cell research.
On the one hand, there is considerable support for research that could lead
to treatments and cures for everything from AIDS and diabetes to heart failure
and Parkinson's disease. On the other hand, elements of the religious community
raise moral objections to this sort of research. The current consensus seems
to parallel the proposed NIH guidelines- research with stem cells left over
from IVF procedures and terminated pregnancies are OK, but research with stem
cells derived from embryos created specifically for that purpose crosses the
ethical line. A recent ABC news poll indicated that Americans support federal
funding of stem-cell research by a 2-1 margin despite controversy over its
use of human embryos.
The
Amazing Stem Cell
The stem cell is a remarkable type of precursor cell that carries within
it the potential to differentiate into virtually any type of cell- e.g. muscle,
nerve, heart - in the body. It has only been a couple of years since researchers
were able to isolate and culture these cells. Stem cell research is already
revealing remarkable new findings about the nature of how cells grow and differentiate
to become an organism. But it is the potential for developing treatments for
specific medical problems that fires the imagination of the public and the
efforts of researchers. For example, a ready supply of insulin producing cells
could provide a new approach to the treatment of diabetes. Similarly, stem-celled
derived heart muscle cells could be a useful treatment for those with failing
hearts, and a ready supply of stem-cell derived nerve-cells could offer a
new hope to patients with spinal injuries.
Since pluripotent stem-cells are most plentiful in embryos, it is not surprising
that many researchers are interested in that source. However, it is worth
noting that stem cells of different types have also been isolated successfully
from umbilical cord tissue, adult bone marrow and muscle cells. Moreover,
researchers at Rockefeller University and Sloan-Kettering Institute recently
announced ( in the April 27 issue of Science) that they had been able to isolate
pluripotent stem cells from the tails of mice that were then induced to differentiate
into viable nerve tissue. The stem cells grafted in the spinal cord, restoring
movements in paralyzed mice. While the this research is in the early stages,
this new direction in stem cell research could offer a way around ethical
concerns (and federal regulations) on the use of stem cells derived from embryos.
Clouds
on the Research Horizon
It is becoming clear that researchers have a long way to go before stem
cell based therapies are available. A recent study in the journal Science
(July 6, 2001) indicated that that embryonic stem cells used in cloning mice
often result in severe abnormalities.This would appear to bolster the case
of researchers working on tissue-specific stem cells harvested from adult
sources.
'The emerging truth in the lab is that pluripotent stem cells are hard to
rein in. 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," noted University of Pennsylvania bioethicist Glenn McGeewas Technology
Review.
|
Related information on the Internet
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
What's News Index
