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Ethical Issues in Human
Embryonic Stem Cell Research
November 24, 2004
Robert Streiffer, Ph. D.
Department of Philosophy
Department of Medical History and Bioethics
Department of Medical Sciences, School of Veterinary Medicine
University of Wisconsin, Madison
rstreiffer@wisc.edu
http://philosophy.wisc.edu/streiffer/

Outline
1. Introduction to hES cells and their potential uses
2. The Benefit Argument for hES cell research
3. The Pro-Life Argument against hES cell research
4. The question of the fetus’s moral status
5. Bypassing the abortion debate: other options
6. Bypassing the abortion debate: research on those who are
already going to die
7. Bypassing the abortion debate: issues of complicity
8. Bypassing the abortion debate: religion and politics
9. Exploitation and Commodification Concerns

What Are Stem Cells?
Stem cells (embryonic, fetal, or adult) are self-renewing cells that are also
capable of differentiating into more specialized cells.
Source: NIH “Stem Cells: Scientific Progress and Future Research Directions”

In late 1998, James
Thompson at UW-
Madison
discovered how to
isolate and culture
hES cells.

What Are Human Embryonic
Stem Cells (hES cells)?
A human embryonic stem cell (hES cell) is a stem cell that is derived
from the inner cell mass of the blastocyst stage of a human embryo.

Properties of hES Cells
hES cells are immortal.
hES cells are pluripotent. That is, they can differentiate
into any kind of tissue in the human body.
Unlike an embryo, they are not totipotent. That is, they
are not (at the present time) capable of being implanted
in a uterus and giving rise to a human being.

Bioluminescent Mice
These nice had a gene from a jellyfish which
expresses green fluorescent protein. This
technique is widely used to tag a cell in such a
way that all of its offspring are also easily
identifiable. This can be used to prove that a
cell is a pluripotent stem cell.

How to Demonstrate Pluripotency
Source: Catherine Varfaillie

hES Cell Colony
(Source: University of Wisconsin-Madison.)
Microscopic 20x
view of a colony of
undifferentiated
human embryonic
stems cells. The
embryonic stem cell
colonies are the
rounded, dense
masses of cells. The
flat, elongated cells
in between the
embryonic stem cell
colonies are
fibroblasts that are
used as a "feeder
layer" on which the
embryonic stem
cells are grown.

Source: “Stem Cells: A Primer”

Drug Development and Testing
http://www.news.wisc.edu/9064.html
hES Cell-derived cardiac cells spontaneously organize
themselves and begin to beat.

90% of what we know about early human development is inferred
by studies on mouse embryos.
hES cells provide a window into early human development that
researchers have never before had.
Developmental Research

Stage 6 Human Embryo Day 7.5 Mouse Embryo
Trophoblast
Trophoblast
Extraembryonic
Endoderm
Extraembryonic
Endoderm
Extraembryonic
Mesoderm
Extraembryonic
Mesoderm
Ectoderm
Ectoderm
Human vs. Mouse Embryology

Tissue/Cells for Therapy
• Multiple Sclerosis results from a
degradation of myelin, resulting in
the interruption of electrical
signals traveling down nerve
fibers.
• Shiverer mice have an MS-like
condition, and so are used as a
model to study potential MS
treatments.
• Researchers injected stem cells
from a healthy mouse into the
brains of shiverer mice. The stem
cells multiplied, migrated
throughout the brain, and became
myelin-producing cells. Injected
mice stopped shivering.
• If injected young enough, shiverer
mice never start shivering.

The Benefit Argument for hES Cell Research
“We believe that not to develop the technology would do great
harm to over 100 million patients in the United States alone who
are affected by diseases potentially treatable by the many medical
applications of hES cells.”
Thomas B. Okarma
Geron President and Chief Executive Officer
“Human Embryonic Stem Cells: A Primer on the Technology
and Its Medical Applications”

A More Rigorous Reconstruction
1. hES cell research is reasonably expected to provide
substantial benefits.
2. If an activity is reasonably expected to provide substantial
benefits, then society is morally required to support it.
(Implicitly presupposed moral premise)
3. Hence, society is morally required to support hES cell
research.

Two Problems
The Benefit Argument begs the question of whether or not the
opportunity costs of funding hES cell research are excessive in
comparison to its benefits. If they are, then society is not morally
required to fund it.
The Benefit Argument begs the question of whether or not hES cell
research violates anyone’s rights. If it does, then society is not
morally required to fund it (even if the opportunity costs of doing so
are not excessive).

The Opportunity Costs Objection
Even if HES cell therapy is beneficial, there are
other more cost-effective uses to which the money
could be put.

We Spend Too Much
• U. S. health care costs are about 15% of our
GNP, whereas other first world countries costs
are around 7% of their GNP
• U. S. health care costs are expected to exceed
30% by the year 2030
• The use of new technology and the overuse of
existing technology is estimated to account for
up to 50% of the rise in health care costs.

And Receive Too Little
• 44.3 million Americans are chronically
underinsured (about 16% of the U. S.
population)
• The U. S. ranks 16th in terms of male life
expectancy
• 13th in terms of female life expectancy
• 6th among industrialized countries in terms of
the infant mortality rate

The Pro-Life Argument against hES Cell
Research
First Stage: It is unethical to derive hES cells because doing so
involves the destruction of a human being with a right to life.
Second Stage: It is unethical to perform any downstream research
on hES cell lines or to use products developed with hES cell lines
because anyone doing so is complicit in the wrongful death of the
embryo from which the cell line was derived.
Third Stage: The government is morally required to prohibit those
unethical activities because activities that are wrong in the way those
are, are legitimate objects of government action.

Can We Bypass the Moral Status Question?
Perhaps there are other sources of
human pluripotent stem cells.
Perhaps some kinds of fatal
research on people are
permissible.
Perhaps researchers who do
downstream research on cell lines
are not complicit in the allegedly
wrongful death of the embryos.
Perhaps views about the moral
status of the fetus are really
religious views, and are therefore
inappropriate as a basis for public
policy.

The First Stage
First Stage: It is unethical to derive hES cells because doing so
involves the destruction of a human being with a right to life.

Other Options: Parthenogenesis
A team led by fertility specialist
David Wininger at biotech firm
Stemron of Maryland has grown
parthenogenetic human embryos to
the blastocyst stage, at which stem
cells can be obtained. Cells taken
from one of the embryos survived
for a few days ( Stem Cells , vol 21,
p 152).
To the right are primate
parthenogenetic embryos.

Mouse Parthenogenesis
Reported in Nature, April 21, 2004. Researchers led by
Tomohiro Kono of the Tokyo University of Agriculture in
Japan managed to bring two parthenogenetic mice to term
(a, b) with one (a) surviving into adult and capable of
reproduction, out of 457 attempts.

Other Options
1. Removal without destruction
2. Adult stem cells
3. Chimeras
4. Genetically engineered embryos

Research on Those Who Are Already
Going to Die
1. Even granting that embryos have a right to life, if they were
going to be destroyed anyway, then it is permissible to
destroy them in the process of deriving hES cells.
2. Given current IVF practices, surplus embryos are inevitable.
(Currently, there about 400,000 frozen human embryos in
the U.S.) Couples have four options:
A. Implant
B. Donate
C. Freeze
D. Discard

Overly Simple
The mere fact that a person is going to die does not permit
research which is certain to cause that person’s death.
1. IVF is permissible.
2. IVF routinely results in the destruction of excess embryos
(600,000 in the past 10 years).
3. Hence, it is also permissible to destruction excess embryos.
4. And if that is permissible, then surely it is permissible to
destroy them in the name of research that has the kind of
potential benefit that hES cell research has.
A Better Argument?

The Second Stage
Second Stage: It is unethical to perform any downstream research
on hES cell lines or to use products developed with hES cell lines
because anyone so doing is complicit in the wrongful death of the
embryo from which the cell line was derived.
This is clearly problematic: not all who benefit from or do research
on someone who was wrongly killed are complicit in that person’s
death.

Bush’s Proposal
Bush’s August 9th proposal:
“As a result of private research, more than 60 genetically diverse
stem cell lines already exist. They were created from embryos that
have already been destroyed, and they have the ability to
regenerate themselves indefinitely, creating ongoing opportunities
for research. I have concluded that we should allow federal funds
to be used for research on these existing stem cell lines, where the
life and death decision has already been made. Leading scientists
tell me research on these 60 lines has great promise that could
lead to breakthrough therapies and cures. This allows us to explore
the promise and potential of stem cell research without crossing a
fundamental moral line, by providing taxpayer funding that would
sanction or encourage further destruction of human embryos that
have at least the potential for life.”

The Third Stage
Third Stage: The government is morally required to prohibit those
unethical activities because activities that are wrong in the way
those are, are legitimate objects of government action.

Are Views about Early Human Life Religious?
Some claim that views about whether or not early forms of human
life have moral status or intrinsic value are controversial religious
views, which do not provide a legitimate basis for state action.

Ronald Dworkin, Life’s Dominion
“The connection between [religious people’s] faith and their
opinions about abortion is not contingent but constitutive—the latter
are shadows of religious beliefs about why human life itself is
important…. We may describe most people’s beliefs about the
inherent value of human life—beliefs deployed in their opinions
about abortion—as essentially religious beliefs.”
“States have no power to impose on their citizens a particular view
of how and why life is sacred.”

Research vs. Surplus
Embryos
1. Many who are in favor of deriving HES cells from surplus
IVF embryos are against the creation of embryos solely for
the purpose of using them as a source of HES cells.
2. Separates fertilization from reproductive intent

Concerns about Exploitation
of Egg Donors
1. Some believe that the increasing medicalization of
reproduction gives men even more power over women’s
lives and will lead to increasing exploitation of women’s
reproductive capacities by men.

Concerns about
Commodification
1. For-profit companies involvement in egg donation and HES
cell research will result in or itself typically constitutes a
problematic commodification of persons.
2. Many committees have agreed that eggs and fetal tissue,
like solid organs, should not be bought and sold.

The Fetal Tissue Debate vs.
the hES Cell Debate
1. Issues of the moral status of the fetus weigh heavily in each, but
on some views, the ex utero/in utero distinction is relevant to the
status of the fetus
2. Issues of complicity are more prominent in the hES cell debate; but
they are also prominent in the debate about the use of fetal tissue
from elective abortions. It is important to note, though, that the
death of the embryo is directly brought about by the harvesting of
the hES cells.
3. HES cell research is motivated by a goal which all agree is
important, human health; abortion is viewed by some as being
motivated by an impermissible desire to abdicate one’s parental
responsibilities.
4. The strongest argument for a right to abort is a right to bodily
integrity, which does not apply in the case of ex utero embryos.

Avenues for Resolution
1. Alternate source of equally useful stem cells
2. Removal of stem cells without destroying the embryo
3. Effective separation of later research from original derivation
4. Consensus on the moral status of the embryo
5. Willful complacency of opponents in the face of successful
therapies
6. Failure of hES cell research to fulfill its potential

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