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As far as dramas go, the stem cell saga contains all the
elements of a juicy prime-time soap opera. The excitement, the promises, the
characters, the politics, the lies, the scandal, the money—the only thing
missing is sex, but that’s the point, isn’t it?
On November 20, 2007, the journals Science and Cell
announced a truly major discovery. It was a way to convert human skin cells
taken from a simple skin biopsy into stem cells that behave like an embryonic
stem cell—but the byproduct is not an embryo and can in no way become one.{1} This
has the effect, say many, of sidestepping the ethically troublesome practice of
creating then destroying human embryos in order to treat diseases.
This new method is efficient. One biopsy can produce 20 stem
cell lines, and can be taken from the patient himself, eliminating the risks
associated with tissue rejection. We hear about stem cell “breakthroughs” all
the time; how is this one different? Is this method ethical? Will it save as
many lives as embryonic stem cells promise to? Is this the end of the stem cell
controversy?
The Saga
Stem cells are simply cells that make other cells. Their job
is to be a cell factory. By analogy, think of a rose. From the stem of the rose
grows leaves, the flower, and thorns. The thorns don’t produce flowers, the
leaves don’t produce thorns, and the flower doesn’t produce leaves, but the
stem does. The stem is versatile; it can make many parts of the plant. Stem
cells operate the same way. Some stem cells are more versatile than others. In
other words, some stem cells can make many types of cells and others can only
make one type of cell.
The history of embryonic stem cells dates back to the 1950’s
when two scientists isolated a teratoma from a mouse. A teratoma is a tumor that
is composed of various types of cells from hair cells to eye cells to teeth to
nails, so the scientists aptly named it a teratoma, or “monster.” When
investigating this tumor, the scientists found that the stem cells that
produced this array of cell types had very similar properties of embryonic
cells. Thus began the investigation into embryonic stem cells.{2}
Before the term “stem cells” had become popular, bone marrow
transplants had been used to treat patients with leukemia. Whenever a patient
receives a bone marrow transplant from a donor, they are really receiving a
type of stem cell therapy. At this point, scientists could only use bone marrow
stem cells for very specific cell replacement. These stem cells were not very
versatile—at least that was the theory at the time. Since then, bone marrow
stem cells have been found to be quite versatile, and can be coaxed into
becoming a variety of cells. Scientists have now found a variety of adult stem
cells throughout the body and have been using them in humans to cure or
alleviate a number of diseases or conditions (see www.stemcellresearch.org for a
complete list).
Another breakthrough with stem cells arose from tissues such
as umbilical cord blood, placental tissue, amniotic fluid and even menstrual
blood—all obtained without harming the life of the baby at any stage of
development. Each of these stem cells are a little more versatile than the
adult stem cells, meaning that they can become two or three different types of
cells, and in many cases the donor/recipient need not be an exact match. The
National Cord Blood Program is just one group that allows parents to put their
baby’s umbilical cord blood in a “bank” so that he or she could use it for
therapy sometime in the future, or they can donate the umbilical cord for
others to use. See www.nationalcordbloodprogram.org
for a list of patient success stories.{3}
If these are adult stem cells, then what are embryonic
stem cells? These are cells removed from the eight-day-old embryo. When these
cells are removed, the embryo dies. These cells produce almost all of the cells
in the human body, and therefore are the most versatile stem cells. You may
have heard of these cells as being “pluripotent.” That simply means that they
are very versatile. Some scientists believed that embryonic stem cells (ESC)
research was where time, money and resources should go since we know that these
cells have the potential to become any cell type.
Numerous success stories of treatments with adult stem cells
have been under-reported by the media, while the supposedly cure-all ESC were
hyped—even though they have shown no actual success in humans. Ironically,
adult stem cells have been saving patients lives for years (bone marrow
transplants), while ESC scientists have yet to control the growth rate of the
ESC. In what shouldn’t be a surprise to anyone, ESC tended to form grotesque
tumors (teratomas) composed of various cells found in the body.
Debate over the ethics of using embryos became heated within
the political arena. The individuality and dignity of the embryo came into
question. Scientists wanted “unfettered” research{4} so that all
options can be explored to cure diseases, while others considered the embryo a
very vulnerable life that has the right to be protected from experimentation. Both
sides claimed to be arguing for the good of humanity.
These debates, however, have taken a slightly different turn
with the recent discovery of converting skin cells into pluripotent stem cells
mentioned above.
Skin Cells
As mentioned, now scientists have isolated human stem cells
that are as versatile as embryonic stem cells, but no embryos were used to obtain
these stem cells. While more studies are needed to confirm that these cells act
like ESCs in the human body, they behave just like ESCs in the lab.
There are a few concerns with this procedure. One of the
biggest concerns is the way these stem cells are made. Both research groups had
to use a type of virus to insert the right code into the skin cells to tell it
to become a stem cell. This virus may be harmful to humans. However, both
scientists are researching safer methods for coaxing the skin cells into stem
cells.{5}
So is this method ethical? I strongly believe the answer is
yes. As Leon Kass, former head of the President’s Council on Bioethics, stated
in a National Review Online symposium, “Reprogramming of human somatic
cells to pluripotency is an enormously significant achievement, one that
boosters of medical progress and defenders of human dignity can celebrate
without qualification.”{6} Sanctity of life advocates can celebrate because no
embryos are created or destroyed for research.
Both scientists who first published on this new discovery, Dr.
James A. Thomson from the U.S. and Dr. Shinya Yamanaka from Japan, said that
this research could not have been done without the knowledge that we already
had from embryonic stem cells. And Thomson, who was one of the first scientists
to remove a stem cell from a human embryo,{7} has specifically stated that
embryonic stem cell research should continue.{8} We must keep this point in mind,
but we must also remember that, contrary to what some in the scientific
community are saying, both scientists had more than just economic reservations
about using embryos in their research:
Thomson: If human embryonic stem
cell research does not make you at least a little bit uncomfortable, you have
not thought about it enough…I thought long and hard about whether I would do it.{9}
Yamanaka: When I saw the embryos, I
suddenly realized there was such a small difference between it and my
daughters…I thought, we can’t keep destroying embryos for our research. There
must be another way.{10}
Is This “Match Point”?
Most people agree that this changes the political and
scientific culture of the stem cell debate. Surprisingly, some major players
have come around.
Jose Cibelli, research scientist whose successful primate
cloning was overshadowed by the skin cell announcement states, “If their method
is as good as the oocyte (the cell that forms a human egg)…we will be no longer
in need of the oocytes, and the whole field is going to completely change.
People working on ethics will have to find something new to worry about.”{11}
Even Ian Wilmut, the scientist famous for creating Dolly the Sheep [see Probe
article], decided to abandon cloning and work with reprogramming cells
instead. As the Britain’s Telegraph reports, “The scientist who created
Dolly the sheep, a breakthrough that provoked headlines around the world a
decade ago, is to abandon the cloning technique he pioneered to create her…. ‘I
decided a few weeks ago not to pursue nuclear transfer,’ Prof Wilmut said.”{12}
Several of the participants of National Review Online Symposium
agree that this removes the ethical concerns from researching pluripotent cells,
and, pragmatically, this seems to be significantly more efficient than cloning
embryos to remove stem cells. Case closed? Not quite.
Not all agree that this is the end of using embryos to
extract stem cells. As Wesley Smith, bioethicist, vocal ESC critic and
Discovery Institute fellow, points out on his blog, www.bioethics.com:
If anyone thought that the pro-human cloners would fold up their tents and steal away after the news was
released that patient-specific, pluripotent stem cells had been derived from
normal skin cells, they just don’t understand how fervently some scientists and
their camp followers want to clone human life—and how hopeful some are that the
stem cell issue can be the vehicle that wins the culture war.{13}
Recall that we are dealing with scientists’ careers and, for
the most part, scientists with a utilitarian worldview. A scientist whose
worldview is dictated by “whatever is for the greater good” and has built his
entire career and reputation around embryonic stem cell research is not going
to readily abandon it. To see the interplay of both career and worldview
choices, Dr. Hans Keirstead, neurobiologist and stem cell researcher at the
University of California-Irvine, had this to say in an interview for the Arizona
Daily Star:
I do think a great deal of this
work could be done with the skin-cell derived stem cells. But we’d have to
start completely over, from scratch, and we are not going to slow down to do
that, not at this point….
“It is my personal feeling it’s a very ethical decision to
use this tissue [Embryonic Stem Cells] to end human suffering, to better human
life, than to destroy it.”{14}
Conclusion:
As Christians, we operate within an ethical framework
dictated by God’s word. Although the Bible does not mention stem cells, it does
make clear that we are made in God’s image (Genesis 1:26, 27), that God knew us
and knit us together within our mother’s womb (Psalm 139: 13-16), and how God
called prophets before they were even born (Isaiah 49:1; Jeremiah 1:4-5). God
values the life of the unborn. We do not always have the privilege of seeing
ethical decisions vindicated in our lifetime, but we can be confident that God
is sovereign over all things.
Notes:
1. Takahashi, Kazutoshi, et al, Cell 131, 861-872, November 30, 2007; Yu, Junying, et al Sciencexpress, www.sciencexpress.org, (fee/registration to access full article) November 20, 2007.
2. “From teratocarcinomas to embryonic stem cells and beyond: a history of embryonic stem cell research” Solter, Davor Nature Reviews 326, vol. 7, April 2006.
3. See list of references from Family Research Council, www.frc.org/get.cfm?i=IS06H01. See also www.stemcellresearch.org/facts/asc-refs.pdf for a sampling of peer reviewed research articles.
4. “This case history [of ESC research] again reinforces the old truism that unfettered basic research driven only by scientific curiosity is usually the best way to discover things of enormous practical value” Solter, Davor Nature Reviews 326, vol. 7, April 2006.
5. “Two Major Studies Show: Human Pluripotent Stem Cells without Cloning or Destroying Embryo” analysis by Maureen Condic, Ph.D. from www.stemcellresearch.org/statement/pptalkingpointsweb.pdf.
6. National Review Online NRO Symposium, nationalreview.com, “Brave New Future.”
7. Thompson, James A. et al, Science 282, 1998.
8. “Standing in the Way of Stem Cell Research” by Alan I. Leshner and James A. Thomson Washington Post, 12-0-07, pg. A17.
9. “Man Who Helped Start the Stem Cell War May End It” by Gina Kolata, New York Times, Nov. 22, 2007.
10. “Risk Taking Is in His Genes” by Martin Fackler, New York Times, 12-11-07.
11. Vogel, Gretchen, and Holden, Constance , “Field Leaps Forward with New Stem Cell Advances” Science 318, 23 November 2007, p. 1224.
12. “Dolly creator Prof Ian Wilmut shuns cloning” by Roger Highfield, Telegraph 11/16/07, www.telegraph.co.uk.
13. “'Lead Into Gold:' Stem Cell Counter-Attack” by Wesley Smith. Posting for November 27, 2007 www.bioethics.com.
14. “Human embryonic stem-cell work must go on, says researcher” by Carla McClain, Arizona Daily Star, 11-28-2007.
© 2007 Probe Ministries
About the Author
Heather Zeiger graduated magna cum laude from the University of Texas at Dallas with a B.S. in chemistry and a minor in political science. She received her M.S. in chemistry, also from UTD; her research was in organic synthesis and materials. She interned at Probe Ministries prior to graduate school and now serves with Probe as a Research Associate and Program Coordinator. She is married to David, another former Probe intern, and is the mother of one cat.
What is Probe? Probe Ministries is a non-profit ministry whose mission is to assist the church in renewing the minds of believers with a Christian worldview and to equip the church to engage the world for Christ. Probe fulfills this mission through our Mind Games conferences for youth and adults, our 3-minute daily radio program, and our extensive Web site at www.probe.org. Further information about Probe's materials and ministry may be obtained by contacting us at: Probe Ministries 1900 Firman Drive, Suite 100 Richardson, TX 75081 (972) 480-0240 FAX (972) 644-9664
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