STEM CELL RESEARCH MEDICAL REVOLUTION OR ETHICAL DILEMMA? BY LAURA HOBBS NATALIE KSEIB. Word count: Approx 2100

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1 STEM CELL RESEARCH MEDICAL REVOLUTION OR ETHICAL DILEMMA? BY LAURA HOBBS NATALIE KSEIB Word count: Approx 2100 Grade awarded June 2006: PASS WITH MERIT RESEARCH PAPER BASED ON PATHOLOGY LECTURES AT MEDLINK 2005 PAGE 1

2 ABSTRACT Whether one views the use of medical genetics as advantageous and non-maleficent or a completely unjust abomination against human dignity, it is clear that ethical issues are of major importance in stem cell research. The next major new medical breakthrough could be found as a result of research and full understanding of the properties and potential of stem cells. In the discussion of this paper, we put forward ideas for the potential of stem cell manipulation in the future, and focus on methods of manipulating and researching stem cells with minimised ethical implications through morally acceptable techniques. Exactly how stem cells should be dealt with however, is of huge importance and it is this that we are basing our research project on. INTRODUCTION Since the cloning of Dolly the sheep in 1997, increased understanding in cell nuclear replacement technology the means of cloning has been the forefront of medical research on the basis of cell differentiation. The focus for today s scientists has shifted to therapeutic cloning using stem cells: more specifically the prospect that these cells hold in human disease for modern day medicine. The unique properties and potential for stem cell manipulation are still in the early phases of research. The principle area of interest is the stem cells unique ability to replicate and grow into any tissue. Therefore there is the possibility that they can be used for organ replacement. Stem cells are found in the body of animals due to the need for constant replacement of terminally differentiated cells. Replacements are generated from a stock of proliferating precursor cells derived from small numbers of stem cells which cells are not terminally differentiated so can divide limitlessly. Stem cells and precursor cells work together, to produce cells with specialised functions of the differentiated cell, but to produce cells that will. The daughter cells produced from stem cell division can take two paths. There is the option of remaining a stem cell, leading to self renewal; alternatively, the cell can mature and develop into a terminally differentiated cell and be used directly in the body. See Figure 1. FIGURE 1 Although stem cells are difficult to identify, there are two types that scientists have been able to extract and research. Embryonic stem cells are obtained from the undifferentiated inner mass cells of human embryo at the blastocyst stage. It is possible to obtain stem cells from an embryo after miscarriage, early abortion or from embryos created by in vitro fertilization. When cultured (in vitro) and provided with the nutrients and growth factors, these stem cells divide to form a constantly growing stem cell line; containing only cells in an undifferentiated euploid state. Scientists are trying to discover a way of making the stem cells differentiate and develop into specific organs so that failing body parts, can be replaced. Signal proteins or chemical signals would be needed to treat the stem cell in order to initiate this process of pluripotency. Alternatively, stem cells have been detected throughout the adult body (e.g. bone marrow) but are in shorter supply than in embryos, and so harder to extract and are only activated when they need to create new cells to replace damaged cells. Currently there is no evidence that they possess the potential to transform into any cell and this is their major limitation. The stimulus to trigger these stem cells to begin division needs to be found before they could be used as easily as PAGE 2

3 embryonic stem cells. The major positive factor of using adult stem cells is that there is no risk of the organ being rejected once replaced into the same adult. This seems a safer and less wasteful use of stem cells and new tissues. Stem cell research has already caused massive ethical debates and controversy world wide. The main concerns arise from the methods of obtaining the stem cell lines using embryos. People are against the deliberate destruction of embryos that may be a possible means of obtaining more stem cells: similar concerns are linked to abortion. Furthermore, the issue of cloning and using a donor to provide stem cells to produce an organ for another person is a sensitive issue. Already researchers have been put under huge restraints and limitations with all studies being closely monitored. For example, it is illegal to carry out stem cell research in Germany, or indeed to provide advice to scientists overseas. There is a lack of funding for research, as people are unwilling to help researchers deal with embryos and stem cells in an unethical way. For example, the US prohibited the use of federal money to work with any embryonic cell lines created after Aug. 9, 2001, because of moral concerns over the destruction of embryos. The US created only 19 usable stem cell lines before that date, and that number is never likely to rise above 23, according to the National Institutes of Health. It is clear that the sensitivity of the nature of the research is causing it to progress slowly. DISCUSSION The focus of our discussion will be firstly on the suggestions of future possibilities of stem cells, and in light of the ethical implications of these procedures, other ways of manipulating or researching stem cell potential in a morally acceptable way. Stem Cell transplant in the Human Brain CNS neural stem cells capable of giving rise to both neurons and glial cells do persist in the ref 8. adult mammalian brain. Adult neural stem cells have been harvested from the brain, grown in culture and then implanted back into the brain of a host animal where they produce differentiated progeny. Results have shown that the grafted cells adjust their behaviour to match their new location. This hints that it may be possible to use neural stem cells to repair at least some types of damage and disease in the central nervous system. Researchers in Doebecher Childrens Hospital at Oregon Health and Science University are running a safety trial involving purified neural stem cell transplantation to see whether injecting stem cells directly into the brain can treat neurodegenerative disorders. This project is aimed at regenerating genes responsible for teaching the body how to make essential enzymes for preventing mutations resulting in neurnal ceroid lipofuscinosis (NCL), a fatal disease in children. If successful, consider the possibility of using stem cells as a means to regenerate damaged areas of the human brain. For example, if the area responsible for sight in the brain was to be damaged by natural causes or by external means, so that they could no longer function, is it so impossible that stem cells already present in the brain, could be stimulated to produce daughter cells to replace the damaged area: thus restoring sight? Perhaps this would be possible by injecting cultured stem cells obtained from an adult brain of the required area directly into the affected area to stimulate regeneration. If the research mentioned above, concerning NCL, were to prove safe and practical, is it really ethically wrong to use this process to save lives and use stem cells in research to these possibilities? PAGE 3

4 Through considering stem cells major ethical concerns, it is necessary to consider alternative methods by which these ideas can be accomplished. If the above proves to be a success, the next step into using adult stem cells in the brain, would be to use the stem cells that are already present from the damaged area or those in close proximity to it. Once a suitable stimulus can be found, there is no need for stem cells to be cultured outside of the patient. Instead, the stimulus could be injected if it is in a suitable form into the brain and cause the stem cells to regenerate on their own. This would reduce the ethical concerns that are connected with culturing stem cells and using a third party to help provide the original stem cells. Embryo destruction In order to extract embryonic stem cells, the embryos are destroyed. Political and religious organizations are concerned about the treatment of these embryos as they are created, destroyed and then discarded. The Catholic Church teaches that the moment a zygote is formed it is owed the unconditional respect morally due to a human person as it has the potential to become a human. In the view of the Catholic Church, it is therefore unacceptable to create and deliberately destroy embryos. Either from IVF or naturally from the mother, the concern for future research is that embryos will be created in mass numbers, probably by IVF using artificial means of conception (this is also a big concern), and all of these will be destroyed. To obtain stem cell lines in the numbers required, alternative methods must developed to avoid both issues. Cord blood is a concentrated source of stem cells obtained from the umbilical cord and placenta immediately after birth. Ethically, it would be the lesser of two evils to use cells from this source for research purposes, as they do not have the potential out of the womb to become a human being and would usually be discarded. It seems a more ethically acceptable source of stem cell lines. Medically this seems logical. Researchers continue to use embryos, arguing that at the early blastocyst stage, even if produced by natural conception, the embryo has no guarantee of survival and may never become a human being. Therefore, we believe the stem cells present in the cord blood from these tissues shouldn t be thrown away but used at least for research, which could in the long run, help to find cures and save lives. A further problem arises, as to the issue of creating stem cell lines from embryos involves chemicals that are obtained from animal cells and products not humans. This is seen as an impure manipulation of the cells which are then placed back into people. Researchers at the university of Wisconsin-Madison, have found a reliable method of growing human stem cells without exposure to animal cells or products. They replaced the animal based components of a culture medium (such as bovine blood serum) with purified human proteins. Successful cells were created. In the UK a stem cell bank has been established to deposit stem cell lines created in the UK for other researchers use. This ensures that stem cells are used responsibly and the fewest number of embryos are destroyed as fewer lines are needed. Social Ethics In all areas of medicine, the cost of treatments for individuals connects to ethical correctness. If this area of medicine stem cells - were to work, the issue of whether one person can be treated while another person can t, just because of the expense of the treatment, would raise massive debates. The church teaches that all people are equal and so everyone should be treated, whatever PAGE 4

5 their financial status. As the process is expensive, it wouldn t be affordable for everyone. To make the treatment available to all people, it could potentially be funded by the government. Whether or not they would agree to this is highly questionable due to the ethics of the medicine. Moreover, this area of medicine (i.e. organ replacement using stem cells from the patient to create a new organ for them, thus no third party is involved) would only work on malfunctioning organs which do not carry genetic mutations. Often the malfunction in organs is caused by someone s choice of lifestyle i.e. drinking affects the liver. Is it fair that great effort and expense is spent on people who have effectively made themselves ill? Using organs produced from embryonic stem cells raises questions about whether it is correct to save someone s life by putting another s at risk (if one views the embryo as a person). Despite the possibility that one embryo could provide organs to help multiple patients, who is in the position to judge who should live and if an embryo should die as a result? A radical objective to this research is the opinion that it is wrong for human intervention to save lives. The belief that the patient s life is in the hands of God suggests it is wrong to treat them in the first place. This corroborates the Christian view of the Sanctity of Life: God created life and only God can destroy life. CONCLUSION Stem cell research definitely appears to hold the potential for significant medical advancements. Once stimuli have been detected and the stem cells are able to be manipulated more easily, the limit to curing disease is inconceivable. Possibilities of using stem cells in the brain, moreover, implies major damage to humans could be reversed and future medical cures could extend to help people far more effectively than current treatments can. Unlike adult stem cells, embryonic stem cells possess the ability to regenerate into other tissues, however the major hindrance concerning these, is the ethical concerns related to obtaining the stem cells destroying embryos. We have suggested possible methods of researching with embryonic stem cells that would alleviate moral concerns; however, a completely safe and socially acceptable method is not yet possible. Once science finds a way of minimising moral concerns, the future of stem cells is a really exciting and potentially life saving area of study. PAGE 5

6 REFERENCES 1. Alberts etal. (4 th edition) Molecular Biology of the Cell, Garland Science. Page Aldhous P. (2006) Miracle Postponed. In New Scientist, 2542, Gross M. (2006) New Cells for Old. Biological Sciences, 18, Nussban etal. (6 th edition) Genetics in Medicine, Thompson and Thompson. Page 345 and Turnpenny P etal. (12 th edition) Emery s Elements of Medical Genetics, Elsevier. Page 357 and US Stem cell research lagging, report by the Boston Globe Animal free stem cells created, report by BBC News Researchers To Study Effectiveness Of Stem Cell Transplant In Human Brain PAGE 6