Spring is the season of renewal—from the Christian belief in the resurrection of Christ to the more secular appreciation of the earth’s rebirth from the winter months. Renewal is a driving force in medical research as well, particularly in the fields of tissue rejuvenation,regrowth and transplantation. Yet, can renewal as a medical therapy be a bad thing?
On
the subject of the biomedical use of human fetal tissue, this is an important
question to ponder. For alongside the promise of fetal-tissueresearch there are uncomfortable realities. As recent ghoulish news
reports have revealed, medical researchers at universities in British Columbia,
Nebraska, Colorado and likely other institutions do not simply order “fetal
tissue” from providers—they order leg bones, livers, spleens, whole eyes and
other organs.
And
despite admonishment from the Canadian Royal Commission on New Reproductive
Technologies and a U.S. congressional prohibition against a money-making
marketplace for fetal tissue, there are clear indications that just such a
marketplace has developed; human fetal parts are being sold for a profit. “In
a civilized society there are things that should not be for sale,” Andrew
Kimbrell, author of The Human Body Shop, said recently. “But right now we are
in an ethical free fall.”
The
most direct clinical application of human fetal tissue has been the decade-long
experience in transplanting fetal brain tissue into the brains of patients with
Parkinson’s disease. Herein lies a tale of desperate hope, moral anguish,
initial scientific and public enthusiasm and ultimate though still strongly
denied—failure. Parkinson’s disease is a progressive, degenerative brain
disorder characterized chiefly by a loss of motor control, involuntary tremor,
muscle rigidity, slowness of movement and problems with balance and walking. The
exact cause of Parkinson’s disease is unknown, but we do know it is associated
with a decline in the production of the brain chemical dopamine. In the early to
moderate stages of the disease, neurologists have a fair degree of success
treating patients with a variety of medications that either boost dopamine
synthesis, or directly stimulate dopamine receptors in key deep brain
structures. After a number of years, however, the effectiveness of these drugs
wears off, or is accompanied by troubling side effects.
A search for
novel therapies has led to a variety of experimental brain surgery procedures.
The theory behind fetal transplantation is that dopamine-producing cells
extracted from the brains of several aborted
fetuses can be injected deep into critical brain regions of the recipient
Parkinson’s disease patient, hopefully to take root and begin to produce the
needed dopamine. However, a series of limited, uncontrolled case reports
provided little evidence of real success, despite tremendous hype that continued
to capture the public imagination.
Finally,
a well-designed study funded by the U.S. National Institutes of Health revealed
that the use of fetal tissue was essentially worthless.
This was an immense disappointment to workers in the field but the public
was shielded from the full force of this result, with headlines such as“Parkinson’s progress” and “Hints of success in fetal
transplants.”
From
an ethical perspective, even for those who do not recognize an individual human
life as beginning at conception, the fetal transplant issue draws attention to
certain scientific facts about early fetal development that should be more than
a little unsettling. Most abortions take place in the latter part of the first
trimester of pregnancy, from eight to 12 weeks. This is exactly the stage at
which fetal brains are removed for potential transplant. Far from being an
undifferentiated “blob” of tissue, the first trimester fetus not only has a
brain but has also developed a fantastic level of specialization.
The
scientist who uses fetal tissue in either pure laboratory research or clinical
experimentation cannot avoid the abortion controversy. Any attempt to do so
risks being seen as a somewhat disingenuous form of denial. Hans Jonas, who
rejects the concept of the moral immunity of discovery, has observed the widely
held view among scientists that “freedom in inquiry is claimed, granted and
cherished as unqualified on the premise that inquiry as such raises no moral
problems.”
Defenders of
the use of fetal tissue often advance two lines of argument.
One, that fetal tissue transplantation is merely an extension of organ
donation, a long and honored form medical altruism. Opponents of the use of
fetal tissue, however, would counter that organ donation arises from tragedies
we try to prevent: fatal accidents, or murder. Abortion, on the other hand, is
an elective choice in our society and many affirm it as an absolute right.
A
second point to be made in support of the use of fetal tissue is the “let’s
not let it go to waste” sentiment, in which even those who profess to be
troubled by elective abortion see the benefit of salvage in making a
contribution to science with material that would otherwise be discarded.
It is probably not unfair to characterize this position as Pontius
Pilate-like in its hand washing of any concern about the troubling source of
this tissue. And what of the limits of this justification of the use of
potentially expedient data, however obtained? Although Professor Michael Marrus
has, recently in this space, wisely cautioned us against the overly
promiscuous invocation of Nazism in bioethical debates, one simply cannot
address the subject of ill-gotten medical data without referring to the
searing examples of human experimentation under the Third Reich or the Japanese
cold-exposure data extracted from murderous experiments on Asian prisoners of
war.
Since the 1988 Supreme Court of Canada Morgentaler decision struck down the old hospital abortion committee law, there has been a legal vacuum on the subject of fetal rights. Moreover, the current unrestrained practice of abortion supersedes a number of recommendations contained in the 1989 report from the Law Reform Commission of Canada, Crimes Against the Fetus. Another Law Reform Commission report, on human biomedical experimentation, goes to the heart of the matter: “At what moment in the development of the product of conception are we dealing with a human being or a human person?”
There
is a troublesome aspect to the unwarranted aura of success that surrounds the
practice of fetal tissue transplantation. A 1995 survey by the Joint Centre for
Bioethics at the University of Toronto found that, among women who would
consider having an abortion, 17 percent would be
more likely to undergo an abortion if fetal tissue could be donated for
medical use. When one considers the current abortion rate of over 100,000 per
year in Canada, and 1.4 million per year in the U.S., the extra number of
abortions that may occur, based on a false premise, becomes a real public health
issue.
The
world of medical research may be passing by fetal tissue transplantation. It is
now over a decade since the experiments began and precious few advances have
occurred. On the other hand, new medications continue to be added to the armamentarium
in treating Parkinson’s disease and there are now two brain surgery
procedures, which do not require fetal tissue, that have been proven effective
at extending the functional longevity of patients with advanced Parkinson’s
disease. University of Toronto neurosurgeon Andres Lozano, in collaboration with
neurologist Anthony Lang, is recognized as a pioneer in the surgical techniques
of pallidotomy and deep brain stimulation.
Recently,
new hope and controversy has arisen with the potential use of implanted stem
cells. These primitive “pluripotent” cells, normally present in the human
embryo, are capable of being coaxed into developing along one of several cell
lines, including brain cells. The controversy has been over the need to use
aborted human embryos to retrieve these versatile cells. Yet even this ethical
dilemma may be averted, following the stunning recent reports that such stem
cells can be found, albeit in small numbers, within the tissues of adult humans.
Although much work needs to be done, some scientists now suspect that each
person may harbor all the cells he or she will ever need to re-grow or
rejuvenate ailing body parts.
Which goes to show that, given time, science will often find a way to advance, without the need to compromise human dignity in the interim.