Human stem cells
What about using adult stem cells?
Sponsored link.
What are stem cells?
As stated elsewhere on this web site:
"The human body contains 220
different types of cells. Stem cells are a type of primitive cell. Scientists have found ways of developing stem cells derived
from embryos into most types of human cells, such as blood,
brain, heart tissue, nerve cells, bones, etc. Researchers are
confident that they will lead to treatments to many diseases....The 'Coalition for the Advancement of Medical
Research' estimates stem cell research shows promise to develop cures
and/or new treatments for 100 million Americans who currently suffer from a
wide variety of diseases and disorders."
The harvesting of stem cells from embryos has become a very hot
political, religious, and ethical topic. As in the debate over abortion
access, the pro-life and pro-choice movements take opposite
positions about the ethics of embryo stem cells research. There
is general agreement that an ovum, spermatozoon, pre-embryo, embryo,
fetus and newborn contain human DNA and are clearly alive. Thus, they
are all forms of human life. The key difference between the pro-life and
pro-choice movements is the point when they believe human life
(as in an ovum or spermatozoon) becomes a human person and is thus
worthy of legal protection:
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The pro-life movement generally believes that this happens at, or
shortly after, conception. Thus, they consider the removal of stem cells
from an embryo -- a procedure which kills the stem cells -- to be a form of
murder of a human being. They argue that no potential health benefits to
even hundreds of millions of people can justify the murder of other
humans. |
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The pro-choice movement generally believes that personhood is
attained much later in pregnancy, perhaps when the fetal brain develops
consciousness during the third trimester. Thus, extracting stem cells from an
five or ten-day old pre-embryo is not murder. Killing a pre-embryo,
which is only a potential human being, is justified if it has the
potential to cure diseases and extend the lives of people. |
Stem cells can also be obtained from sources other than embryos. They are
called "adult stem cells." Their use is relatively free of ethical
conflicts. Both the pro-life and pro-choice movements favor further research
on stem cells from these sources.
Researchers began using adult stem cells from bone marrow back in 1960.
It was only in 1998 that other researchers were able to isolate and
cultivate embryo stem cells. 12
Adult stem cell research thus has an almost four decade head start compared
to embryo-derived stem cells. As of 2004-Fall, promising trials were underway
using adult stem cells. By mid-2007, there are many experimental treatments
available using adult stem cells. Meanwhile stem cells from embryos are still being
experimented upon in the laboratory.
In late 2007, a method was made public of
reprogramming adult stem cells to have many of the properties of embryonic
stem cells. This has the potential to combine the potential range of treatments
and cures of embryonic stem cells with the lack of ethical concerns over the use
of adult stem cells.
Sponsored link:
Where do adult stem cells come from?
Some sources:
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One supply is from human fetal tissue. The first human stem cells
were extracted from "primordial gonadal tissue which was taken
from a non-living fetus." 1 Fetal tissue research can be legally funded
from government sources. |
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Advanced Cell Technology claims that they have been able to extract human stem
cells by fusing human fetal tissue with parts of a cow's egg. 2 |
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Stem cells can be extracted from brains of cadavers, from bone marrow
of living patients, from umbilical cords, and from human placentas.
Unfortunately, such extraction is more difficult, and gives smaller yields.
Also, it has been generally believed that the cells produced have limited potential.
They can only produce a few of the 220 types of cells in the human
body. |
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Canadian researchers at the Montreal Neurological Institute
have studied the second layer of skin, the dermis. It contains "skin-derived
precursors" or SKP's. These stem cells have been coaxed into
producing four different cell types. They also grow well in the
laboratory. Of particular importance is that the cells contain the
same DNA as the subject; thus there is no danger of rejection. They
can be transplanted without the necessity of the patient taking immuno-suppressant
drugs. |
Promotion of adult stem cell research by the pro-life community:
The pro-life community promotes the use of stem cells from these
sources, because they do not require the killing of an embryo. Most
spokespersons promote adult stem cells as superior to those extracted from
embryos. They rarely, if ever, mention that:
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Adult stem sells may lack the potential to generate all the
tissue types needed. |
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Adult stem cell research is more advanced, at least in part, because
of its four decade head start over embryo stem cell studies. |
Some statements supporting adult stem cell research:
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James Dobson: Undated: |
"Focus on the Family encourages scientists
to continue to explore stem cells found in adult tissues, bone marrow
and umbilical cord blood. Initial research using these sources are
considered to be very promising, even more promising in some instances
than embryonic stem cell sources." 2
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Jakki Jeffs of Alliance for Life Ontario: 2001-JUL: |
"Adult stem cell research provides a legitimate, moral and
ethical alternative area of research. Adult stem cell research has
already been used successfully for therapeutic benefit in human beings..."
3
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Canadian Physicians for Life: 2001-APR: |
"The scientific literature overwhelmingly demonstrates that
adult stem cells are already fulfilling the goals only hoped for with
embryonic stem cells, making the destruction of human embryos
unjustifiable." 4
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Bioethicist Dr. Nigel Cameron: 2002-SEP: |
"We know that adult stem cells, which have no ethical problem,
can do the job, as well." 5
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Massachusetts Family Institute:
2004-OCT: |
"Adult stem cells are regenerative cells of the human body
that can be coaxed to become a whole host of tissues, including heart
tissue and neural matter. With these adult stem cells, physicians have
successfully treated autoimmune diseases such as lupus, multiple
sclerosis, Crohn’s disease, and rheumatoid arthritis. They have also
restored proper cardiac function to heart attack victims, and improved
movement in spinal cord injury patients. Embryonic stem cells have yet
to yield one single success in the treatment of any ailment."
6
Original assumption: adult stem cells have limited potential:
Research prior to 2002 caused researchers to conclude that adult stem cells are very limited in potential.
They are difficult to obtain, grow slower, and are less robust when compared to cells extracted from embryos.
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National Institutes of Health stated that: "...there is
evidence that adult stem cells may have more limited potential than
hPSCs [human pluripotent stem cells]. First, stem cells for all cell and
tissue types have not yet been found in the adult human. Significantly,
cardiac stem cells or pancreatic islet stem cells have not been
identified in adult humans. Second, stem cells in adults are often
present in only minute quantities, are difficult to isolate and purify,
and their numbers may decrease with age." 7 |
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Newsroom.com reported that: Cells from
adults "are available in far smaller quantities and could treat
only a limited range of body parts, researchers contend. No adult stem
cell has yet been found that could treat heart disease, for example, so
scientists would rather cultivate embryos to harvest their stem cells."
8 |
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The National Bioethics Advisory Commission stated:
"In our judgment, the derivation of stem cells from embryos remaining
following infertility treatments is justifiable only if no less morally
problematic alternatives are available for advancing the research … The
claim that there are alternatives to using stem cells derived from
embryos is not, at the present time, supported scientifically.
We recognize, however, that this is a matter that must be revisited
continually as the demonstration of science advances."
9
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Adult stem cells may offer greater potential
than originally believed:
In early 2002, New Scientist
magazine reported that Catherine Verfaillie's team at the
University of Minnesota had found stem cells in the bone marrow of
adults that may be capable of becoming almost any of the 220 tissue types in
the human body. These "multipotent adult progenitor cells" or (MAPCs)
might match the flexibility and potential of stem cells derived from
embryos. Verfaillie's team, was able to isolated MAPCs from about 70 of the
approximately 100 people who donated samples of their bone marrow. 10
Meanwhile, Osiris
Therapeutics has produced "mesenchymal stem cells" (MSCs) which
has been shown capable of producing a few tissue types, such as bone,
cartilage, fat and muscle. They have one unusual property: when
transplanted, they appear to trigger little or no immune reaction. 11
The jury is still out on the
relative potential of adult and embryo stem cells:
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Steve Brozak, a New York biotechnology investment
banker who is running for Congress in New Jersey as a Democrat said: "This
is voodoo science. This is only a political sidestep. Adult-stem-cell
research holds no real promise that I can see. It's not usable."
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Jay P. Lefkowitz, a former adviser to Bush on
stem-cell policy said: "Adult stem cells are really where the real
progress is being made."
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A new technique was announced in 2007-NOV that may be able
to reprogram adult stem cells to behave as if they
had many of the properties of embryonic stem cells. This may allow adult stem
cells to have the same potential as embryonic stem cells without significant
ethical concerns.
References used:
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Anon, "Human Embryo research/fetal experimentation," Focus on
the Family, Policy statement dated 1997-DEC-15. See: http://www.family.org/
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"Focus on the Family statement on human embryo stem cell research,"
at:
http://www.family.org/d
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Jakki Jeffs, "An alternative exists to embryonic stem cell research,"
Toronto Star, 2001-JUL-6
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"Stem Cell Research," Canadian Physicians for Life, at:
http://www.physiciansforlife.ca/
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Steve Jordahl, "Calif. Governor Signs Stem Cell Bill," at:
http://www.family.org/
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"Stem Cell Research," Massachusetts Family Institute,
E-Alert, 2004-OCT-14.
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National Institutes of Health guidelines for research using human
pluriopent stem cells," at:
http://www.nih.gov/
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"Britain debates cloning embryos to treat disease,"
Maranatha Christian Journal, at: http://www.mcjonline.com/
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"Ethical Issues in Human Stem Cell Research," , National
Bioethics Advisory Commission September, 1999. Quoted in: The Coalition of
Americans for Research Ethics at:
http://www.stemcellresearch.org/
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Sylvia Pagan Westphal, "Is this the cell that could revolutionise
medicine?," 2002-JAN-26, New Scientist (http://www.newscientist.com)
Online at:
http://www.eurekalert.org/
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Sylvia Pagan Westphal, "Greater potential of adult stem cells
revealed," New Scientist, 2004-MAY-17, at:
http://www.newscientist.com/
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Michael S. Rosenwald, "Researchers Turn To Adult Stem Cells.
Biotech Firms See Potential for Medical Use," Washington Post,
2004-AUG-220, Page E01. Online at:
http://www.washingtonpost.com/
Copyright © 2004 to 2007 by Ontario Consultants on Religious Tolerance
Latest update: 2007-NOV-21
Author: B.A. Robinson
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