Thursday, June 11, 2009

Stem Cell like human cloning (including the cloning of embryos) has stirred controversy in our world. On March 9th 2009, contrary to recent and dramatic scientific evidence, President Obama signed an executive order authorizing tax dollars to fund embryonic stem cell research. It is highly controversial because human embryos are killed in order to obtain stem cells.People think that President Obama’s decision appears particularly political when made in the immediate wake of two scientific announcements. The Bentham Open Stem Cell Journal just published documentation of the first successful adult stem cell treatment to reverse the effects of Parkinson’s disease.
According to Dr Irving’s (a former career-appointed research biochemist/biologist (NIH), as well as a Ph.D. philosopher specializing in the history of philosophy, and medical ethics) article on stem cell, “science is moving at warp speed these days -- cloning, gene therapy, miracle drugs, and exotic therapies. One of the most significant breakthroughs came in November 1998, when two separate researchers successfully isolated stem cells from human embryos and aborted fetuses. The impassioned hopes are that these stem cells can be used to great advantage. The cautious fears are that innocent and vulnerable human beings are destroyed, and needlessly so, in the process. The debates are raging. Many people are confused about what stem cell research really is, and wonder why all the fuss. There are several well documented and well-articulated sources of information available on this issue already. The purpose of this essay is to explain what stem cells are and whether or not it should be legalised.
Stem cells are essentially primordial cells of a human organism (i.e., a human being) which are capable of becoming all or many of the 210 different kinds of tissues in the human body. Stem cells have been traditionally defined as not fully differentiated yet (or, not fully determined yet) to be any particular type of cell or tissue. They range from "totipotent", i.e., almost totally undifferentiated and capable of becoming any tissue in the body (as in the early human embryo up to about the 4-day morula stage), to "pluripotent", that is, more differentiated and therefore only capable of becoming some cells or tissues in the body (as in the 5-7-day blastocyst stage of the early human embryo, with decreasing capacity in later stages of fetal development, and in adult human beings). Studying stem cells will help us understand how they transform into the dazzling array of specialized cells that make us what we are. Some of the most serious medical conditions, such as cancer and birth defects, are due to problems that occur somewhere in this process. A better understanding of normal cell development will allow us to understand and perhaps correct the errors that cause these medical conditions. There are two types of stem cells — unlimited stem cells (also known as embryonic stem cells) and limited stem cells (also known as adult stem cells).Unlimited stem cells are currently obtained with patients' permission from leftover three-day old embryos that would otherwise be discarded from fertility clinics. These embryos are created and exist entirely outside the body. Unlimited stem cells can develop into any kind of cell type or tissue in the body. Limited stem cells are rare cells that can be found in only some developed organs or tissues. Limited stem cells have been successfully used for some time now in bone marrow transplants (either with bone marrow stem cells or umbilical cord blood stem cells) and skin and hair transplants.
Stem Cells are also source of all body tissues. Stem cells can replicate themselves or make any type of cell required to build an organism. Our growth and development from single cell to mature adult arises from and is maintained by stem cells. Moreover, stem cells may provide powerful tools for biological research and medicine. Stem cells are cells found in most, if not all, multi-cellular organisms. They are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types. Research in the stem cell field grew out of findings by Canadian scientists Ernest A. McCulloch and James E. Till in the 1960s. The two broad types of mammalian stem cells are: embryonic stem cells that are isolated from the inner cell mass of blastocysts, and adult stem cells that are found in adult tissues. In a developing embryo, stem cells can differentiate into all of the specialized embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such as blood, skin or intestinal tissues.
When a sperm cell fertilizes an egg, the process creates a stem cell. Some scientists consider the zygote, or fertilized egg, itself to be a stem cell, whereas others believe that the zygote must divide a few times to form stem cells. The unspecialized stem cell can make all other cells, from additional stem cells to bone cells, blood cells, muscle cells, skin cells, and all the specialized cells that make up body tissues. As a human develops and matures a stockpile of stem cells remains in every organ of the body. Although all cells can divide to make copies of themselves, only stem cells can create other cell types.
To explore potential medical uses of these cells, scientists need stem cell lines. These lines are colonies of stem cells that grow and replicate themselves in culture—that is, in a special nutrient substance in a laboratory dish. A stem cell line provides a scientist with a virtually endless supply of material to explore and test. Stem cells, however, seem to lose some of their ability to make a wide range of cells as they age. In other words, an older stem cell may not be as versatile as a younger one. The exception seems to be adult stem cells derived from bone marrow, which retain their ability to transform into any cell type. As a result, adult stem cells from bone marrow and the earliest stem cells, those found in an embryo may provide the most powerful tools for use in medical treatment.
Stem cells, which create a human from its beginning, also participate in repairing later damage to the body. Our bodies appear to use stored stem cells to repair tissues throughout our lives. Eventually, these stem cells falter or encounter more damage than they can repair, and a person’s health fails. Because of their ability to repair tissue damage, stem cells could serve as starting points in therapy for a wide variety of medical conditions, including Alzheimer’s disease, which damages brain cells, especially those related to memory, and Parkinson disease, which damages nerves that control the muscles.
Scientists are investigating two primary approaches to using stem cells in medicine. The first approach involves developing stem cells that could be transplanted to combat a specific disease. For instance, someone with a liver disease might receive a dose of liver stem cells. Someday, a regular medical regimen might even include an occasional dose of stem cells, much like a booster shot, to keep the body tuned up to fight off diseases and tissue damage. The second approach involves learning to use the body’s own supply of stem cells. Perhaps these stores of cells could be turned on or off as needed to help the body defend itself against health problems.
Despite the promise of stem cells, they have stirred considerable controversy. In large part, the controversy surrounds the source of stem cells used in research. Most of these stem cells come from embryos, in particular embryos left over from infertility treatments. Therefore the argument against the legalisation of stem cells should be understood in the context of embryonic stem cells which threatens the sanctity of human life. Pope Benedict XVI said “History has condemned such science in the past, and will condemn it in the future, not only because it is devoid of the light of God, but also because it is devoid of humanity."
"In the face of the direct suppression of human beings," he continued, "there can be no compromise or prevarication; it is inconceivable for a society to fight crime effectively when it itself legalises crime in the field of nascent life."
“A good end" of medical breakthroughs by using embryonic stem cells, he said, "can never justify intrinsically illicit means." Again, during a treatment known as in vitro fertilization, eggs that have been surgically removed from a female ovary are placed in a laboratory dish with male sperm. In some cases more than one egg becomes fertilized, creating extra embryos. Embryonic stem cells come from embryos at a very early stage, about the time the embryo would have attached to the wall of a uterus.
Although a patient may need only a few embryos, in the process of creating them, several more are made. The ones which are not implanted in the uterus are eventually discarded. Each year it is estimated that couples undergo 120,000 cycles of fertility treatment using in vitro (outside the body) fertilization (IVF), and from these cycles 7,500 embryos are discarded. Each of these embryos can be used to create a large number of unlimited stem cells.
Again, the use of embryonic stem cells in medical research raises a fundamental question: Do these cells come from human tissue or from humans? Some people oppose the use of anything, including stem cells, from an embryo that is viable (able to grow). For people who take this philosophical position, stem cell research involves the destruction of a human life. Considering the above argument against the legalisation of Stem Cells, it is obvious that the proponents think that it should not be encouraged because it destroys the sanctity of human life.
An opposing viewpoint states that these embryos would never develop into humans, because they would be either discarded or kept frozen in laboratories for future research. Consequently, some people argue that this material should be used in any way that could possibly improve human life. Any argument for the legalisation of stem cells should focus on adult stem cells. Pope Benedict XVI recently declared the churches stand in support of adult stem cell. The Pope endorsed adult stem-cell research, urging Catholic scientific institutions to increase their efforts and establish closer working relationships with others in the field to promote breakthroughs that can relieve needless human suffering.”( He stressed that the church draws a distinct ethical line against research that fails to respect the dignity of the human person and does not heed the “church's constant call for full respect for human beings from the moment of conception.” “If there has been and there still is resistance, it was and is against those forms of research that involve the planned suppression of human beings who are already alive, though they may not yet have been born," he said. Promising horizons are being opened through the use of adult stem cell in the cure of illnesses involving "the degeneration of tissues with consequent risks of invalidity and death for those affected," the pope said. “Research into somatic stem cell merits approval and encouragement when it brings together scientific knowledge, the most advanced technology in the field of biology, and the ethic that postulates respect for human beings at every stage of their existence," he said. Adult stem cells are more accurately called somatic stem cells, as they need not come from adults but can also come from children or umbilical cords, and do not require the destruction of embryonic human life. The pope encouraged those working in Catholic scientific institutions to increase somatic stem cell research and "to establish closer contact among themselves and with others who seek, using appropriate methods, to relieve human suffering.”
He praised the congress participants’ commitment to and hope of "achieving new therapeutic results by using cells from the adult body without having to suppress newly-conceived human beings.”
Furthermore, speaking at the conference, an official of the U.S. Conference of Catholic Bishops said that embryonic stem cell research continues to pose the ethical problem of destroying human embryos, but increasingly poses the ethical problem of deceiving the public as well. More so, Richard M. Doerflinger, interim executive director of the U.S. bishops’ Secretariat for Pro-Life Activities, said the recent scandal involving Dr. Robert Lanza of Advanced Cell Technology, who claimed he had obtained stem cells from human embryos without harming them, is “the latest in a series of deceptions” by those promoting embryonic stem cells. For Doerflinger, “we do not need a fairy tale. We need the truth. But a fairy tale is what we are sometimes getting – not only from politicians and entrepreneurs but from respected scientific journals. This must change, or science itself will lose credibility.”

The fundamental criterion of medical science must be the defence and promotion of the integral good of the human person, in keeping with the dignity which is ours by virtue of our humanity. Consequently, it is evident that every medical procedure performed on the human person is subject to limits: not just the limits of what is technically possible, but also the limits determined by respect for human nature itself, understood in its fullness: “What is technically possible is not for that reason alone morally admissible” (Congregation for the Doctrine of Faith, Donum Vitae, 4). Therefore in my ardent opinion and from the foregone discussion, it is obvious that embryonic stem cell threatens the sanctity of human life and so does not stand a fair chance of being legalised. However, adult stem cell should be legalised because it does not threaten the sanctity of human life.
Some people who oppose the use of embryonic stem cells point out that the scientific investigator could rely on other sources. A variety of body tissues including bone marrow and blood from an umbilical cord can also provide stem cells. However, no one knows if these tissues produce stem cells that equal embryonic cells in their versatility and thus in their potential for treating human disease.
Adult stem cells, such as blood-forming stem cells in bone marrow (called hematopoietic stem cells, or HSCs), are currently the only type of stem cell commonly used to treat human diseases. Doctors have been transferring HSCs in bone marrow transplants for over 40 years. More advanced techniques of collecting, or "harvesting," HSCs are now used in order to treat leukemia, lymphoma and several inherited blood disorders. The clinical potential of adult stem cells has also been demonstrated in the treatment of other human diseases that include diabetes and advanced kidney cancer. However, these newer uses have involved studies with a very limited number of patients.

Written on request of Fr. Thomas King, S.J., Ph.D., Department of Theology, Georgetown University; President, University Faculty For Life, for their newsletter, "UFL Pro-Vita". .org.
Becker AJ, McCulloch EA, Till JE (1963). "Cytological demonstration of the clonal nature of spleen colonies derived from transplanted mouse marrow cells". Nature 197: 452–4. doi:10.1038/197452a0.
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