Sheila Mullet
November 25, 1996
Biology Senior Seminar
What is it that makes fetal tissue so valuable to research? Due to certain
properties of these young cells, they are perfect for a number of uses in
medicine and research. There are four main properties that give fetal cells
this potential for a successful transplantation. The first property is their
ability to grow and proliferate after transplantation. By growing, it is
more likely that the transplanted cells will become a functional part of
the recipient's existing tissue. In fact, researchers believe that at some
point in the future they will be able to grow a full functioning kidney
from a few fetal kidney cells.
Along with their ability to grow and divide rapidly is the fetal cells'
ability to produce trophic substances. These are the growth factors which
help the cells to proliferate quickly. They also promote the regeneration
of adjacent damaged tissue of the recipient. (Council...Affairs 566)
Another significant trait of these cells is the fact that they have no surface
markers which are what the immune system of the recipient identifies as
foreign and attacks. Therefore, the transplanted fetal cells are much less
likely to be rejected by the new body.
Probably the most important feature is the "plasticity" of the
cells. This refers to the fact that these young cells have not been differentiated
yet. They still have the potential to become just about any type of cell.
The young cell just has to be transplanted into the desired region and it
will mold its growth to become that type of specialized cell.
"In addition, it [fetal tissue] can be successfully cryopreserved and
reanimated." (Harris, 3) With this feature, the tissue can be frozen
and saved to be used at later time. If usable tissue can be saved until
when it is needed, shortages may be prevented.
The use of fetal cells for transplantation is a relative recent development.
In 1928, the first transplantation was done with fetal cells. Surgeons in
Italy transplanted fetal pancreatic cells to a patient with diabetes. Unluckily,
there was no lasting improvement in the patient. Fetal cells played an important
role in the development of vaccines. It wasn't until 1968 that a successful
transplantation took place. Fetal liver cells were grafted into patients
suffering DiGeorge syndrome, a rare and usually fatal genetic disorder.
(Begley 49) Fetal tissue transplantation became the accepted treatment for
this rare disease.
Since then, fetal cells have helped patients with many other ailments.
There are a wide range of afflictions which the use of fetal tissue can
treat and help reduce symptoms. Parkinson's disease, diabetes, blood and
immune system disorders are a few of the areas that are now being treated
with this type of procedure.
Probably the most promising is the treatment of Parkinson's. This is a common
disease, usually affecting at least 500,000 people in the United States
at one time. This disease results in lack of control of movement, and the
patients experience uncontrollable shaking, rigidity, and eventually paralysis.
It is due in part to the destruction of the area of the midbrain that is
responsible for motor movements. There is then a resulting imbalance of
dopamine, which is a neurotransmitter, that causes the shaking and the tremors.
There are drugs that stimulate the production of dopamine in the brain and
are effective treatments. But a very specific amount is needed or else psychosis
can result. Therefore, fetal neural cells that are injected into the damaged
area of the brain may provided a permanent source of dopamine.
Immune disorders are another area that fetal tissues are helping to combat.
Much research is being directed to this area and definite progress has been
made. Not only has immune function often been reestablished, but there is
a good rate of long term survival for patients. Fetal liver cells have been
found to be an important site of blood formation. This is important because
the fetal tissue cells have a low amount of immunocompetent T lymphocytes
compared to adult bone marrow. When bone marrow is used in transplants to
treat immune disorders, the immunocompetent T lymphocytes cause graft versus
host disease. So the fetal cells help to almost eliminate this problem in
transplants.
Diabetes is also being treated with fetal tissue. In this disease, insulin
is not produced by the pancreas, and the blood sugar level rises. Patients
suffering from diabetes have to inject themselves with insulin, usually
one to two times a day. Insulin cannot be given orally because it is a peptide
and will be broken down by digestive enzymes. At the University of Colorado,
fetal pancreatic cells have been transplanted into diabetics since 1987.
All transplants have been successful, meaning the fetal cells have fused
and have begun to produce insulin. This is not yet a cure, but all of those
that have received the treatment require less insulin than before the transplant.
The future of fetal tissue transplantation is filled with possibilities.
I will briefly mention a couple of these options. One option involves transplanting
fetal ovaries into an infertile woman. The fetal ovaries would contain potentially
a few million eggs, and would grow into normal functioning ovaries with
normal estrous cycles. In a case like this none of the children would have
the mother's genetic makeup. Also fetal tissue may become an important part
of the research into a cure or treatment for AIDS. By transplanting fetal
cells into mice without immune systems, human immune systems can be developed.
These mice are then used as models to test new treatments.
From all of the previous information, it is obvious that the use of fetal
tissue is beneficial. But many ethical and moral questions arise from those
who question its humanity. Pro-life groups, those who are opposed to abortion,
raise the most objections. There seem to be two extremes to this argument
involving fetal tissue.
It is important to note that researchers only use the tissues of non-living
fetuses. They are not intending to take tissue from the fetuses before they
are dead, or keep them alive solely to produce tissue. There are laws and
regulations to prohibit this type of activity. But this clarification raises
the question of the status of the fetus.
This dilemma has been pondered countless times. When does life begin? When
does the mass of living and growing cells in the womb acquire the rights
and privileges of a living being? "At one point a new human being is
but a single cell; nine months later that being has fully developed organ
systems and is ready for life, however tentative, on its on." (Kogan
94) There is no clear point in which the transition is made from ball of
cells into human. The term fetus is used from the eighth week until birth,
described as the developing human. Science seems to be unable to answer
this question for us, so we must decided it in another realm.
But this is not a discussion of the morality of abortion. Abortion is legal
in this country and about one and one-half million elective abortions are
performed each year. All these abortions provide an abundant source of fetal
tissue that could be used by researchers. As of now, women who receive abortions
are regularly asked to approve the use of fetal or other tissue from the
abortion to be used in research. Typical abortion consent forms used by
hospitals have clauses that state the tissue can be used for scientific
purposes. In 1993, President Clinton repealed a ban on the federal funding
of fetal tissue research.
Even though abortion is legal in this country, it is morally opposed by
many people. One of the big worries of pro-life groups is the possibility
that the number of abortions will increase due to the fact that the tissue
will be used in a positive way. They fear women will be influenced in their
decision making process by knowing their fetus could help someone who is
suffering. To combat this problem, woman
considering abortion should not be asked for their consent until after they
have decided to go through with the abortion. A safe guard to keep doctors
from influencing women to have abortions is that the doctors who perform
the abortion can't be the one using the tissue in research or therapy.
Even though some see abortion as immoral, it needs to be made clear that
the researcher and the patient who receives the tissue do not necessarily
condone the abortion. One situation that is used to illustrate this point
deals with the Nazis. This may seem like a rather odd connection, but there
are some similarities. The Nazis used the Jews in their concentration camps
for many medical experiments. These experiments were unethical and inhumane.
They caused incredible human suffering and pain. But yet, some valuable
information was collected. And just because medical professionals use this
information today does not mean that they support the Nazi system. So those
fetal tissue researchers and patients who receive fetal transplants should
not be condemned for using it. The tissue would be discarded anyway, so
shouldn't it be used to possible help someone.
Some worry that conception and abortion will start to occur for the sole
purpose of production of fetal tissue. It is feasible to imagine this in
the case of trying to help oneself or a relative. The question then arises
about soliciting an unrelated woman to donate tissue. Will fetal tissue
soon be sold to the highest bidder? Critics worry that this will turn woman
into fetal factories. But this charge could also be made against any living
donor, whether of kidney, bone marrow, blood, sperm, or egg." (Robertson
668)
Another worry of the adversaries of the use of fetal tissue is that there
is no legislation to stop fetal tissue from being used for cosmetic and
other nonmedical purposes. In Canada, researchers have found that injecting
fetal tissue into damaged tissue of animals promotes and speeds up healing.
Some even suggested that soon fetal tissue will be used in a way similar
to steroids, to raise the ability of athletes. Worries of private companies
taking over the sale of fetal tissue and turning it in to a million dollar
industry pervade ethical arguments. These scenarios make it obvious that
this procedure needs to be regulated well. One problem is that since it
is a surgical procedure, individual hospitals have the responsibility of
regulating themselves. This may lead to biased decision making, as the hospital
committees can be influenced by their own politics.
As of now, it is illegal to sell or buy fetal tissue. Many women are reassured
to think that by donating the fetal remains some good can come out of their
abortion. So they offer the tissue for altruistic motivation or to comfort
themselves. But there may be a time down the line when the demand is greater
than the supply. Will we then begin paying women to have abortions and donate
the tissue? This may seem to be a long way off, but its something we need
to think about.
Another issue that may come up in the future is one of maintaining the pregnancy
until the fetus is at a stage more conducive to retrieving the tissue. Is
it ethical to ask the woman to be burdened a little more in order to obtain
more desirable tissue? As long as the woman agrees and no harm is done,
there shouldn't be a problem.
One suggestion that has been made is that only fetal tissue from ectopic
pregnancies is used. There are around 75,000 ectopic pregnancies a year
in the United States. This occurs when the fertilized egg implants outside
of the uterus. The embryo must be removed or both the embryo and mother
will die. This type of abortion is differs from a spontaneous abortion in
that it is usually healthy tissue. When an abortion occurs spontaneously,
it is usually abnormal. For instance, it may be chromosomally abnormal or
be infested with microorganisms. Therefore it is not safe to transplant
this tissue into another patient. But an ectopic fetus would be safe. The
fetus will have to be killed anyway, so shouldn't some good come out of
this tragedy?
Our research and medical fields do not exist in a moral vacuum, so we often
have to deal with the ethical situations that they present. These types
of dilemmas often involve intense feelings. This arguments reach into our
hearts and our definition of ourselves as individuals. So these ethical
questions can not be taken lightly or viewed as unimportant. Each side of
the argument must be examined and treated fairly.
In the case of fetal tissue transplantation, the feelings are elevated because
of the controversial nature of abortion. Since this is an issue that is
dividing the country now, it seems impossible to reach a decision that will
satisfy the majority of people. This issue raise abstract questions which
are difficult to answer.
Some people suggests that the ethical concerns should not be considered
in the fetal tissue debate. President Clinton, in 1993 after removing the
ban of federal funding for transplanting aborted fetal tissue, said his
goal was "to free science and medicine from the grasp of [abortion]
politics." (Begley, 49) This is a commendable objective because during
this ban there wasn't much progress in this field. But we cannot disregard
the ethical aspect of the situations. For example, there are some types
of research that could be done that almost everyone would agree should be
avoided. We still need to have ethics in research, no one would argue that
fact. There is a fine line between ethics guiding the field and ethics prohibiting
its growth.
As you can see, the main issue is the question of the status of the fetus.
Does saving one life justify ending another? How does one weigh the value
of life? Until these questions can be answered in complete ways, we need
to do the best with the information we have. And even with
all the arguments, fetal tissue transplantation has so many benefits that
it needs to be researched and used to help all those who are suffering that
it can.
Begley, Sharon. "Cures From The Womb." Newsweek 22 Feb. 1993:
49-51. Council on Scientific Affairs and Council on Ethical and Judicial
Affairs. "Medical Applications of Fetal Tissue Transplantation."
JAMA 263 (1990): 565-570.
Harris, Rod, Ellen Mayo, Jim Tankersly. "An Introduction to Fetal Tissue
Transplantation." On-Line. Internet. Available: http://www.gene.com/AE/AE/AEPC/WWC/1992/fetaltissue_transplants.html.
Kogan, Barry S. A Time to Be Born and A Time to Die, the Ethics of Choice.
Aldine de Gruyter, New York. 1991.
Roberston, John A. "Rights, Symbolism, and Public Policy in Fetal Tissue
Transplants." Allocations, Social Justice, and Health Policy. 663-673.