Stem cells are cells that renew themselves by cell division and are capable of maturing into many different cell types. They could therefore be used for cell and tissue replacement. The use of human stem cells for research purposes has been going on for some time now. It is important to state that there is nothing intrinsically wrong with stem cell research as such.
New opportunities in transplanting tissue that is histocompatible and not subject to rejection is an exciting field which can lead to substantially reducing much suffering and avoid immuno-suppressive treatment that is currently sustained by patients needing a transplant.
In this regard adult stem cell research, which uses totipotent stem cells (immature cells which are capable of transformation into any specific cells of the body under the right chemical and physical conditions of growth) which are derived from adult human sources of so-called haemopoetic tissue (bone marrow, spleen, lymph nodes - tissue which produces blood cells) and blood itself, does not offer any ethical difficulties. Research in this area is developing at a fast pace.
Depending on their origin, a distinction is drawn between
1. Embryonic stem cells (ES) from embryos derived from in vitro fertilisation (IVF) or cloning of human embryos,
2. Embryonic germ cells (EG) cells from natural or medically assisted terminations of pregnancy (natural or induced abortion),
3. Neonatal stem cells from blood taken from the umbilical cord immediately after birth,
4. Adult or somatic stem cells that can be derived from many tissues of born human beings throughout their whole life (AS cells).
The ethical problems with stem cell research are reserved for so-called embryonic stem cell research. There are sources of 'embryonic' stem cells that are available from cord blood (collected from a cut umbilical cord just after delivery) which do not present any problems (neonatal stem cells). Neither is there an ethical problem with EG cells as long as the termination of pregnancy is natural.
Of course, if the abortion is induced, that is another matter completely. The problem arises because stem cells are also available as tissue found in the embryo in the first few days of development (ES). Certain researchers are harvesting stem cells by the voluntary destruction of the human embryo. In fact these cells may only be obtained by the destruction of the embryo itself.
Some justify this as a necessary price to pay for research to proceed, others argue that spare embryos left over from in vitro fertilisation would die anyway, so it would be better to get some positive benefit out of them, before they become worthless.
Whichever way one looks at this, two facts are indisputable. The first is, that human life is being used for research purposes and destroyed in the process. The second is, that human beings are being commodified on an increased scale and being rendered an object of financial and economic gain, the demand will increase the supply!
The ethical problems associated with the destruction of human embryos, are not the only ones. Some countries have started the procedure of cloning human embryos first, so that iso-immune cells can be obtained which can be used in transplantation. That is, an individual's cells are first cloned by nuclear transfer (transferring the cell nucleus as happens in reproductive cloning), and the resulting embryo is then destroyed to obtain cells that are histologically compatible with the cells of the donor, thereby obtaining good tissue for transplantation.
Here the ethical and legal problems mentioned in the first protocol on Human Cloning of the Bioethics Convention of the Council of Europe are still inherent. That is, there is a breach of the principles of liberty, individuality and equality mentioned in the European Convention of Human Rights. Both reproductive and therapeutic cloning breach these principles, and the Bioethics Convention considers both in the same light, with out even referring to the word cloning, but to the voluntary reproduction of an individual with the same genetic material.
Other ethical problems that are encountered in human stem cell research are surely those of patenting and ownership. Do the harvested cells belong to the donors or to the researchers? Should they be patented at all? What about the rights of the sacrificed embryo, which is the human being from which the cells originally emanated? These considerations require profound and deep analysis.
It is also important to add, at this juncture, that it has been found scientifically impossible to actually use embryonic stem cells in adult tissue, since the absence of tissue markers renders growth containment to be impossible and therefore favours the development of malignant tumours.
Like all subjects in biotechnology, this field is extremely promising for medicine, but the ethical and legal considerations must also be put in place.
In Malta we have no such legislation, which is why we should accede to the Bioethics (Oviedo) Convention of the Council of Europe as soon as is reasonably possible and augment it in the ratification process with local legislation to control any abuses in the future!
Dr Asciak is chairman of the Bioethics Consultative Committee and lecturer in Bioethics at the University of Malta.
michael.asciak@gov.mt