When we think of organ and tissue transplantation, we first might think of the donation of fully developed human body parts like kidneys, hearts, lungs, or skin. There are, however, some forms of transplantation that only involve the donation of human cells and other forms that involve material that is, in fact, not human at all.
In this reflection, we will consider these cellular and non-human kinds of organ and tissue transplantation, specifically, the transplantation of (non-human) animal organs, artificially produced organs, and human stem cells. Animal and artificial organs can be desirable for transplant due to a relatively low supply of donated human organs. Stem cells, sometimes harvested from a patient’s own body, can often be used to repair or replace damaged or diseased tissue. Many of these forms of transplantation are already practiced, and researchers continue to look for new possibilities and more advanced treatments in these areas. As is frequently the case, however, these new technological advances raise additional ethical questions.
Transplanting Animal Organs
The transplant of an animal organ to a human being (sometimes called “xenotransplantation”) is not necessarily unethical. If a human body can assimilate a healthy animal organ in place of a diseased human organ, it is, in principle, well and good. However, human bodies tend to reject animal organs because human immune systems recognize such transplants as foreign substances. For this reason, there have been attempts to introduce human genes into developing animal zygotes so that developed animal organs can be successfully assimilated into human bodies. The primary concern with this practice, from an ethical point of view, is that the distinction between human and animal begins to be blurred. If an animal zygote is given human genes that will in some ways determine its development, would the developed organism then be some sort of hybrid between animal and human? If so, producing such an organism would be a perverse manipulation of the reproductive capacity of the human person. Furthermore, the resulting animal/human hybrid would be of uncertain moral status. Even if such an organism were to display no features of human behavior or consciousness, that would not exclude the possibility of its being human. After all, we recognize that an organism has the status of a human person not by how an organism is able to function but by the kind of being it is. A human embryo is recognized as a human person because it is a biologically distinct member of the human species. When a animal/human hybrid is created, there is no way to be certain whether or not its biologically human characteristics are the expression of a biologically distinct human being.
Artificially Produced Organs
Artificial replacements for human organs have long been relied upon to treat kidney failure and perform heart surgeries. Hemodialysis and heart-lung machines are commonly employed in contemporary medicine. These treatments can obviously be of great value and possibilities for the development of further use of artificial organs or organ replacement are well worth pursuing. However, ethical questions do arise. There have been instances of failed experimentation with artificial hearts that have resulted in multiple human deaths. Great caution must be taken before replacing naturally developed organs with man-made substitutes. There are also potential problems relating to human identity. As with xenotransplantation, the combining of human and artificial tissue may someday result in blurring the distinction between what is human and what is not.
Stem cells are human cells that can reproduce themselves and develop into a variety of specialized cells. Stem cells can be harvested from many different parts of a developed human body (adult stem cells) or from human embryos (embryonic stem cells). Adult stem cells are currently being used for medical treatments, most especially for bone marrow transplants. The stem cells used in bone marrow transplants are sometimes taken from the patient’s own body. The use of adult stem cells in transplants is often effective in treating disease and does not raise particular ethical concerns. Embryonic stem cells, on the contrary, have not yet been used successfully to treat disease. They have been used in research with the hope of developing treatments. Furthermore, the harvesting of embryonic stem cells is morally evil because it involves the destruction of the human lives of the embryos from which the cells are harvested, who are conceived with the intention of being destroyed. Those who use already-harvested embryonic stem cells for research also act immorally because they cooperate with and encourage the destruction of human lives at the embryonic stage.