Stem Cell Research Parish Education Program
The text for the parish education version is given below, and may be read by those wishing to learn about stem cell research and therapeutic cloning from a Catholic perspective.
For further information about the complete "program in a box" or to obtain a copy, contact the Office of the Health Care Consultant by e-mail at DBQCHEAL@arch.pvt.k12.ia.us or by telephone at 563 556-2580 ext. 228.
Termed a scientific "breakthrough," announcements of this event were carried in the media not only in the United States but in other countries as well -- by the Washington Post, the Chicago Tribune, the New York Times, the BBC, and the German Der Speigel.
This development was described as having "profound implications for transplant medicine, drug discovery and basic developmental biology." It was described as "opening the door to growing from scratch everything from heart muscle to bone marrow and brain tissue."
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Cells such as heart cells and skin cells are committed to perform a specific function. A stem cell, on the other hand, is "uncommitted," and it remains this way until it receives a signal to developed into a specialized cell.
There are three sources of stem cells.
First, some stem cells are found in adults. An adult stem cell is an unspecialized cell that occurs in a specialized tissue, renews itself, and becomes specialized to yield all of the cell types of the tissue in which it is found. In other words, adult stem cells serve as a natural replacement mechanism for specialized cells in an adult.
Stem cells can also be obtained from umbilical cord blood and the placenta. These have been placed in the category of "adult" stem cells.
Second, stem cells have been obtained from fetal tissue coming from aborted pregnancies. Technically called embryonic germ cells, these stem cells are derived from the region of the fetus destined to develop into the testes or ovaries.
Third, stem cells have been isolated from early stage human embryos.
The process of obtaining embryonic stem cells typically begins with embryos produced through in vitro fertilization (IVF). Often what are called "spare frozen embryos" are used. In the process of in vitro fertilization, a large number of ova are retrieved and fertilized to create embryos. However, only about three embryos are transferred back to a woman at any given time in the attempt to achieve a pregnancy. This is to try to avoid multifetal pregnancies (that is, twins, triplets or more). The remaining embryos are frozen for later use should a pregnancy not be achieved. However, frozen embryos can become "spare" if a couple achieves the number of children they want through IVF. Embryos can also become "spare" if a couple becomes discouraged with a lack of success in achieving a pregnancy and gives up trying to have a child by this means. Such "spare frozen embryos" may be donated by couples for research purposes. In addition, embryos may be deliberately created through IVF to be a source of stem cells. These have been called "research embryos."
Scientists at the University of Wisconsin - Madison have succeeded in growing red blood cell colonies derived from human embryonic stem cells. They have also succeeded in producing neural cells from human embryonic stem cells. However, transplantation of such tissues faces the well-known problem of immune rejection that we have seen with organ transplants. This is because the stem cells derived from embryos (or, for that matter, from fetuses) would be genetically different from the recipient.
One method for overcoming this problem which researchers are exploring is cloning.
In a procedure known as "somatic cell nuclear transfer," an ovum has the DNA in its nucleus removed. It is then combined with a non-reproductive body cell from the intended recipient. In this way the recipient's set of genes is programmed into the embryo, which will begin to develop.
When the appropriate stage of embryonic development is reached, the procedure described above for obtaining stem cells would be used.
This procedure is known as therapeutic cloning to distinguish it from the potential use of cloning to produce a child for a couple with infertility problems.
Researchers are looking to stem cells as a way to replace cells and tissues in the body that are damaged or diseased in order to restore bodily functions.
Stem cells could potentially be used as a therapy for a variety of diseases and conditions. Stem cells might be used to grow nerve cells to repair spinal cord injuries and restore function to paralyzed limbs. They might be used to grow heart muscle cells to replace useless scar tissue after a heart attack. Stem cells might also be used to make brain cells that would secrete dopamine for the treatment and control of Parkinson's disease, or to grow cells that make insulin to create a lifelong treatment for diabetes. Stem cells might be used to grow bone marrow to replace blood-forming organs damaged by radiation or disease, or to make blood cells which are genetically altered to resist a specific disease (such as HIV) to replace diseased blood cells.
Alzheimer's disease, end-stage kidney disease, liver failure, cancer, and multiple sclerosis are also among the medical conditions for which stem cells might provide a therapy.
One important question being debated is whether stem cells from embryos, fetuses, and adults are equally useful for research and therapeutic purposes.
A report from the National Institutes of Health released in July 2001 proposes that human embryonic stem cells are easier to grow in a laboratory than adult stem cells. According to this report, millions of cells can be generated from one embryonic stem cell, and these cells will remain in an undifferentiated state. On the other hand, when adult stem cells multiply, they tend to become specialized.
Embryonic stem cells and embryonic germ cells from fetuses also have the property of being pluripotent. In other words, they have the ability to give rise to any type of specialized body cell.
Adult stem cells are not pluripotent. However, adult stem cells may exhibit plasticity. In other words, an adult stem cell from one tissue may have the ability to generate the specialized cell type of another tissue. For example, adult stem cells from bone marrow can generate cells that resemble neurons and other cell types commonly found in the brain.
Some researchers point to various limitations of adult stem cells. For one thing, stem cells from adults have not been isolated for all tissues of the body. In addition, adult stem cells are often present in only minute quantities and are difficult to isolate and purify. Morover, the number of adult stem cells present in a person's body decreases with age, and adult stem cells may contain genetic disorders and abnormalities.
But others point to success stories with the use of adult stem cells which have already taken place.
For example, heart attacks are a leading cause of death in the United States. Scientists at the National Institutes of Health and the New York Medical College have done experimental work with mice which has shown that adult stem cells isolated from mouse bone marrow can become functioning heart muscle cells when injected into a damaged mouse heart. Further , the new cells can restore (at least partially) the heart's ability to pump blood. This fact is important for future clinical application in humans.
One of the researchers commented: "Our results indicate the great potential of adult stem cells to differentiate into other cell types and repair a damaged organ, a property commonly attributed to embryonic stem cells...This may allow us to utilize a patient's own stem cells as a new therapeutic option."
The use of adult stem cells has not been questioned from a moral point of view. However, it should not be forgotten that even this research must follow ethical norms for legitimate research and experimentation on human beings.
The ethical controversy surrounds the use of stem cells derived from embryos --which are destroyed in the process of obtaining the stem cells -- and those derived from fetuses which have been electively aborted.
This is clearly stated in the Ethical and Religious Directives for Catholic Health Care Services, a document from the United States Conference of Catholic Bishops: "Catholic health care institutions should not make use of human tissue obtained by direct abortions even for research and therapeutic purposes." (No. 66)
Why has the Church taken this moral stance? After all, if a fetus has been aborted, there is nothing that can be done to restore the fetus's life. So why not allow some good to come out of this tragic situation by allowing the fetus's tissues to be used to benefit other people?
A reason for the Church's opposition lies in the moral concept of complicity with wrongdoing -- that is, in some way becoming an accomplice to the wrong act or a participant in it.
Another form of complicity in abortion would consist in knowingly benefitting from abortions.
It is true that not all cases of benefitting from the immoral acts of other people make one complicitous with their evil acts. For example, heirs of a murdered relative may benefit financially from the murder, and owners who claim insurance on an abandoned building set on fire may benefit financially from the act of arson. Nevertheless, they are not considered complicitous with the murderer or arsonist just because they benefit from their immoral acts.
Moreover, even persons who benefit repeatedly from immoral acts are not necessarily complicitous in these acts. For example, transplant surgeons and others may benefit from the results of drunken driving, assaults, and murders, but they do not directly intend to benefit from these immoral acts. Rather, it is the premeditated, intentional seeking of benefit from the wrongdoing of others that constitutes complicity in wrongdoing.
If one holds the belief that abortion is always immoral, then one cannot decide to use tissue from aborted fetuses without directly intending to benefit from the wrongdoing of others. Thus, the belief that abortion is immoral leads to the conclusion that using tissue from aborted fetuses (for example, to derive stem cells) involves an unacceptable complicity with abortion.
In defense of using tissue from aborted fetuses, an analogy is often drawn with the transplant of organs from homicide and accident victims. No one would claim that the surgeon who transplants the homicide or accident victim's kidneys, heart, liver or corneas, or the recipient of this tissue, become "accomplices" in the homicide or accident that made the organs available. Doesn't the same hold true of researchers who use tissue from aborted fetuses and of the patients who may be recipients of the products of their research?
However, it has been argued that this analogy does not hold true, because it ignores the dimension of an "institutional partnership...whereby the bodily remains of abortion victims become a regularly supplied medical commodity." A more accurate analogy would be a hypothetical case in which a surgeon contracted with a murderer to provide him organs for transplantation, to tell him when and where the organs would be made available, to arrange for the surgeon to be present to have the organs in "fresh" condition, and to reimburse the murderer for any expenses incured in making the organs available. In this case, the actions of the transplant surgeon would be considered morally wrong. Yet these are the types of arrangements that are routinely made to obtain tissue from aborted fetuses.
There are three possible sources
of embryonic stem cells: spare frozen embryos at reproductive clinics,
embryos which have been deliberately created for research purposes using
sperm and ova, and cloned embryos. The first two categories of embryos
depend for their existence on the process of in vitro fertilization (IVF).
Cloned embryos are likewise created "in vitro" in a laboratory
This document reiterated the idea that the conception of a child should take place as part of a loving, interpersonal act of sexual intercourse between a couple. Thus it judged technological methods of assisting reproduction to be impermissible which totally separate the beginning of a human life from that interpersonal act of intercourse. On this basis, the procedures which eventually yield embryonic stem cells, namely, in vitro fertilization and cloning, are themselves morally impermissible and should not be practiced.
However, the main line of controversy about embryonic stem cell research revolves around the status of the early embryo, which is destroyed in the process of obtaining stem cells. Is this early embryo a human being with a right to life? Newsweek magazine captured the essence of this controversey in a subtitle below a picture of the early embryo: "What is the value of this clump of cells? Another human or a new hope for the diseased and dying?"
Three views have emerged on
the standing of the early embryo from an ethical point of view:
The third position has been taken by the Ethics Advisory Board for Geron, a biopharmaceutical company working with embryonic stem cells.
This Ethics Advisory Board
has adopted a developmental view of human personhood and of moral
status: as the conceptus develops from blastocyst to fetus and beyond,
so too does its moral status grow. The Board has affirmed the principle
of respect for human life. However, their developmental view means that
the principle of respect for life entails different obligations at different
developmental stages. As interpreted by this Board, "early embyronic
tissue is respected by ensuring that it is used with care only in research
that incorporates substantive values such as reduction of human suffering."
And, according to this Board, the potential of human embryonic stem cell
research "to contribute to fundamental knowledge of human development
and to medical and pharmaceutical interventions to alleviate suffering"
does "provide such substantive values...".
The Catholic tradition views a human being as a composite of body and soul, with the soul being a direct creation of God. Thus we have a complete human person when the bodily matter provided by the parents becomes "ensouled." And hence we have the question, "When does ensoulment take place?"
In this regard, Donum Vitae states: "Certainly no experimental datum can be in itself sufficient to bring us to the recognition of a spiritual soul; nevertheless, the conclusions of science regarding the human embryo provide a valuable indication for discerning by the use of reason a personal presence at the moment of this first appearance of a human life: how could a human individual not be a human person?"
Donum Vitae relies on three arguments in reaching this conclusion. First, fertilization represents the beginning of a new human life distinct from that of the parents. Second, the genetic material for this new being -- technically, its "genome" -- is put together at fertilization. This set of genes will determine that it develops as a human being (rather than another sort of plant or animal) and will influence at least some of its individual traits. Third, the biological identity of a new human individual is already constituted in the zygote resulting from fertilization.
Some have challenged the position taken in Donum Vitae on biological grounds.
First, the early embryo can split to form identical twins (or triplets or more). This allegedly provides evidence that the early embryo is not yet one human being, but in effect a community of possibly different individuals.
This apparent absence of individuality in the early embryo is seen as raising problems for a belief in immediate ensoulment at the time of fertilization. This is because a soul is an individual reality and every distinct human person can have only one soul. Can a collection of cells that can become more than one person be considered an ensouled human being?
In dealing with the phenomenon
of twinning, some Catholic theologians have pointed out that the embryological
evidence suggests not that the original organism splits, but that it remains
itself but loses one or more cells that become the twin. Further, they
argue that the fact that a group of cells is able after separation to
develop independently into a second individuated organism in no way refutes
the prior existence of an individuated organism. Moreover, they point
out that God can ensoul the twin when it separates just as God ensouled
the original organism when it came into existence.
However, this is a biological phenomenon which is statistically abnormal. Thus it is reasonable not to generalize from these cases to what holds true for most human embryos in terms of ensoulment. Moreover, when we come to know more about why this biological complication occurs, it may become apparent why these embryos were not immediately ready for ensoulment.
Another biological phenomenon brought forward against ensoulment at the time of fertilization is natural wastage. This refers to the failure of early embryos to implant in a woman's uterus in order to continue their development. Such embryos are simply discharged from the woman's body. Although estimates of the rate of natural wastage vary, some claim that between two-thirds and three-quarters of all fertilized ova do not go on to implant in the womb. Hence the question is raised: "In view of this high rate of embryonic loss, do we truly want to bestow much moral significance on an entity with which nature is so wasteful?"
In reply, some theologians have pointed out that, historically, at least 50% of all infants died in infancy, yet this mortality rate does not make us think that these infants were not ensouled. Further, there are cases in which the process of syngamy--the fusion of the nuclei of the ovum and sperm into the single nucleus of the zygote-- can fail to complete. Thus it has been speculated that many of these imperfectly fertilized ova were never prepared for ensoulment and were never truly human organisms.
Before concluding this discussion of the ethics of embryonic stem cell research, there is another issue in this debate which deserves attention.
Some argue that there is a difference between deliberately creating embryos to obtain stem cells and obtaining them from spare frozen embryos remaining at reproductive clinics. These spare frozen embryos may eventually be discarded or destroyed anyway. So the argument is made that it would be better to use them for the greater good of research that has the potential to save and improve other human lives.
At least two points can be brought forward in rebuttal of this line of argument.
The first point is by way of analogy. We do not kill terminally ill patients for their organs although they will die soon anyway. We do not harvest vital organs from death row prisoners although they will be put to death soon anyway. The same should hold true for spare frozen embryos.
The second rebuttal is from
a legal standpoint. Federal law prohibits federally funded researchers
from doing any harm to an unborn child slated for abortion, although that
child will soon be discarded anyway. Again, the same principle should
hold good for spare frozen embryos which are destined to be discarded.
On August 9, 2001 President George Bush announced his policy on federal funding of embryonic stem cell research. He decided that federal funds could be used only for research on some 60 stem cell lines then in existence "where the life-and-death decision has already been made." According to President Bush, "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."
More specifically, federal
funds may only be used for research on stem cell lines in existence on
August 9, 2001 that were derived
No federal funds may be used
It should be noted that this policy applies only to federally funded research. It does not impact the work of privately financed biopharmaceutical companies.
Speaking on behalf of the United States Conference of Catholic Bishops, Bishop Joseph Fiorenza called Bush's position "morally unacceptable." Why is this the case?
One reason was stated by Fr. Michael Place, President and CEO of the Catholic Health Association of the United States: "...what could appear as a carefully nuanced solution to a complex issue--utilizing the already existing cultured stem cell lines--itself raises significant moral concerns for our society. Because these cell lines resulted from the destruction of human embyronic life, their origin is morally reprehensible. The continued use of these cultured stem cell lines by scientists involves complicity in the destruction of embryonic human life."
In order to understand Fr. Place's statement, it is necessary to recall our earlier discussion of complicity with wrongdoing: the premeditated, intentional seeking of benefit from the wrongdoing of others makes one a participant in that wrongdoing. Certainly, researchers who choose to use the existing stem cell lines derived from destroyed embryos fall into this category.
There is an interest in stem cell research because of the potential of these cells to provide therapies for a wide range of diseases and disabling conditions. To obtain these medically valuable stem cells, there are three possible sources: adults, aborted fetuses, and early embryos.
On ethical grounds, it is not permissible to use aborted fetuses and early human embryos as sources of stem cells.
Often the impression is given that we are dealing with an all-or-nothing situation: either we allow the use of stem cells obtained from destroyed embryos, or we completely forgo life-saving therapies and condemn millions of people to continued suffering and to death. However, this is not a fair description of the situation.
As indicated in a report issued by the National Institutes of Health in July 2001, it is presently "impossible to predict which stem cells -- those derived from the embyro, the fetus, or the adult ...will best meet the needs of basic research and clinical applications." In other words, the therapeutic potential of adult stem cells cannot be ruled out. Indeed, some successes have already taken place using adult stem cells.
In his statement of August 9, 2001, President Bush also made a commitment to provide federal funding for research on adult stem cells. This is a part of his position which can and should be actively supported by Catholics.
Do No Harm - The Coalition of Americans for Research Ethics. http://www.stemcellresearch.org
Human Fetal Tissue Transplantation
Research Panel, National Institutes of Health. Report of the Human
Geron Ethics Advisory Board.
"Research with Human Embryonic Stem Cells: Ethical Considerations."
The Washington Post. "Bush
Announces Position on Stem Cell Research."
Embryonic Stem Cell Research at the University of Wisconsin - Madison http://www.news.wisc.edu/packages/stemcells/ [This web site is from one of the centers for embryonic stem cell research. It includes a basic explanation of embryonic stem cells, an illustrated explanation of how embryonic stem cells are obtained and cultivated, and a section giving news and updates on stem cell research. The section "For News Media" includes photographs illustrating embryonic stem cell research.]
Secretariat for Pro-Life Activities, United States Conference of Catholic Bishops, "Cloning and Embryo Research" http://www.nccbuscc.org/prolife/issues/bioethics/factsheets.htm [This web site contains various articles written from a pro-life perspective.]
Do No Harm The Coalition
of Americans for Research Ethics http://www.stemcellresearch.org/
Prepared by Janine Marie Idziak,
Ph.D. Health Care Consultant, Archdiocese of Dubuque, IA