Embryonic Stem Cell Research

Introduction

The employment of cloning and human embryonic stem cells is of the most significant innovations in medicine (Wobus 640). The discovery of the ability to manipulate embryonic stem cells has created the fields of regenerative medicine and cellular therapy, which aim to treat debilitating and/or fatal conditions that were earlier acknowledged to be incurable (Taupin 75). Unfortunately, this breakthrough has brought forth issues regarding the value of life. Technically, cloning of embryonic stem cells involves the collection of embryos that are ethically regarded at the earliest stages of human life (Brown 24). Ethical arguments have arisen, questioning whether it is right to improve life by destroying another human life in the form of an embryo. This paper will describe the technique of therapeutic cloning as well as enumerate ethical arguments that renounce the use of cloning technology and the use of spare embryos for biomedical research and therapeutics.

Main body

Stem cell technology involves the use of self-renewing cells that may be manipulated to differentiate into a cell type that is needed in order to replace any existing defective cells. There are potentially three major types of stem cells that may be differentiated based on their capacity to undergo the biological process of maturation. Progenitor stem cells are the biological units of an organization that have the capability of generating only one type of cell. Examples of progenitor stem cells include epidermal stem cells which are expected to differentiate into keratinocytes only. Another example of progenitor stem cells is the spermatogonial stem cell which can only further mature into a sperm cell. The second type of stem cell is the multipotent stem cell which has the capacity to evolve into different types of cells that comprise a particular tissue or even an entire organ. An example of a multipotent stem cell is the skin stem cells which have the capability to differentiate into several cell types that are characteristic of the skin tissue. These include the cells of the epidermis, the sebaceous or oil glands of the skin, and the follicles of the hair. The third type of stem cell is the pluripotent stem cell which has the ability to differentiate into any cell type. Pluripotent stem cells that are derived from the primordial germ cells of a fetus are technically called embryonic germ (EG) cells. On the other hand, the pluripotent stem cells that are collected from the inner cell mass of an embryo are known as embryonic stem (ES) cells.

Embryonic germ cells play an essential role in serving as cell resources for the tissues and organs of the developing fetus. In the case of an adult, embryonic germ cells replace any tissues that are known to have a restricted life span, such as red blood cells which are known to live and circulate through the bloodstream for only 90 days. Hence embryonic germ cells are important in providing a continuous source for new cells that are needed for the normal functioning of the body. Stem cell technology relies on the fact that a fetus carries more stem cells than an adult.

Stem cells are collected from three general sources. There are approximately 20 types of adult stem cells existing in an adult human body. These adult stems cells have the power to differentiate into specific organs such as bone, liver, and cartilage. Unfortunately, the process of find adult stem cells is quite intricate due to the fact that these specific stem cells are located in unique areas of the body. For example, nerve stem cells can only be found in the brain of an individual hence it is difficult to collect nerve stem cells unless the particular organ is available for laboratory use. Fetal stem cells are generally derived from the blood collected from the umbilical cord of a fetus. The collected is restricted to fetuses that have been terminated and similar to adult stem cells, fetal stem cells can only grow in culture for a limited duration. The isolated fetal stem cells have the capacity to generate embryonic germ cells. Embryonic stem cells are derived from the inner cell mass (ICM) of 5 to 7-day old human embryos or blastocysts right before their implantation along the walls of the uterus (Bongso et al., 1994). These stem cells are cultured in vitro over mouse embryonic fibroblast feeder cells supplied with growth serum. Embryonic stem cells have the ability to infinitely self-renew and sustain their capacity to differentiate into any form of mature cell. Depending on the kind of trigger stimuli introduced, these cultured cells may be controlled to differentiate into the cell type needed for research, experimentation, and therapeutics.

Embryonic stem cells are derived from the inner cell mass (ICM) of 5 to 7-day old human embryos or blastocysts right before their implantation along the walls of the uterus. These stem cells are cultured in vitro over mouse embryonic fibroblast feeder cells supplied with growth serum. Embryonic stem cells have the ability to infinitely self-renew and sustain their capacity to differentiate into any form of mature cell. Depending on the kind of trigger stimuli introduced, these cultured cells may be controlled to differentiate into the cell type needed for research, experimentation, and therapeutics.

Stem cells are collected from four different (4) sources— from surplus embryos or by-products of in vitro fertilization (IVF) laboratories, from “spare” embryos obtained from embryo donors at IVF clinics, from embryos created by somatic cell nuclear transfer (SCNT) or the removal of the nucleus from a body cell and reinsertion into an egg cell, and lastly, from aborted or terminated fetuses. No matter which route is used to collect stem cells, the use of embryos for stem cell research has been the center of ethical debate since its conception. The principle of ethics involves careful deliberation on the use of stem cells as related to human well-being and human freedom. Several issues regarding this new technology have raised uproar and disagreements between the scientific community and ethics groups.

One major ethical issue regarding the use of “spare” embryos is the lack of respect for the embryo. The concern is associated with the possible future demand for embryos once this cellular technology is determined to be successfully therapeutic. Embryos might later be treated as therapeutic materials or commodities instead of living beings at their initial stages. There is also a risk for a devaluation of embryos, wherein the loss of human life may later in time be tolerated instead of prevented (Bobrow 140). In addition, the acceptance of the destruction of embryos may serve as a precedent for the implementation of other controversial biomedical acts such as the creation of embryo “factories”, cloned babies, and mass production of “spare parts” from fetuses (Hug 1008). There is a claim for the scientific community that the employment of spare embryos may not automatically mean any disrespect towards embryos because the destruction of embryos in order to collect stem cells results in the provision of new therapeutics for specific medical disorders. Certain scientists have actually claimed that it is more immoral to destroy embryos during in vitro fertilization because those embryos are not implanted or donated for further use but are actually discarded, unlike embryos that are destroyed for stem cell research which are cautiously propagated and ultimately designed to replace defective tissues and cells for medical therapeutics. Such rebuttal from the scientific community is not good enough because they actually approach the issue of choosing between the lesser evil option.

Another major issue that is being publicly scrutinized is whether the creation of embryos for research purposes is morally worse than using “spare” embryos from IVF cases for experiments. Such issue reflects the intention of each act, and the idea of using leftover embryos from in vitro fertilization protocols is much more tolerable to society than the simple creation of research-oriented embryos because there is less guilt involved in using extra or spare embryos from IVF cases than creating embryos that could have been another human being but their chance to live has been taken away. The scientific community has tried to explain that the production and destruction of spare embryos is a normal physiological event during pregnancy, which enables a sibling embryo to complete the entire gestational range (Borge 60). They claim that this kind of sacrifice is also necessary to promote life for the sibling embryo.

Michael J. Fox, the celebrity-turned-advocate who has been strongly linked to the campaign for the legalization of stem cell research, has raised approximately $35 million for the duration of 4 years, in order to support research efforts on Parkinson’s disease. He established the Michael J. Fox Foundation which is currently the second-biggest funding agency in the United States. Mr. Fox has strongly campaigned for the application of stem cell technology as a promising new tool for the treatment of Parkinson’s disease and similar neurodegenerative diseases. Parkinson’s disease afflicts adults, which age of onset of 40 years, and is represented by persistent shaking of the extremities and rigidity of the muscular system, eventually resulting in difficulty in mobility. Co-morbidity analyses have shown that Parkinson’s disease occurs together with senile dementia. In Mr. Fox’s own words, he has expressed his regret over the restriction and prohibition of stem cell research. On the other side of the issue is the opposition, primarily spearheaded by the Catholic Church and related individuals campaigning against abortion. These individuals claim that stem cell research is immoral and is a modified version of cloning. United States President George W. Bush rejected the bill on stem cell research in August 2001 which stipulates prohibits funding of research programs on stem cell research. As all stem cell systems have been put on hold in the United States, laboratories around the world have continued with their research on stem cells, resulting in promising research results from the United Kingdom, Japan, and Spain, to name a few.

Newspapers have described how stem cell research is perceived by two sides of the issue. Both sides have aggressively used the media in helping them air out their concerns and excitement, respectively, over the use of embryonic stem cells. The newspaper article was written and published a few days before the Senate would meet to determine the fate of embryonic stem cell research in the United States. The stem cell research bill was initially reviewed in 2001 and indicated that research efforts on embryonic stem cells in the United States will not be funded due to ethical reasons. This new bill will thus take control of the 2001 restriction and will therefore allow funding of research programs on embryonic stem cells that have been created as of August 2001. The bill aims to preserve and protect human embryos from their destruction, yet several scientific groups have claimed that this restriction has hampered their research efforts on regenerative medicine, and has also resulted in the lag of research output. More importantly, other countries that are not restricted from performing embryonic stem cell research have gained a 5-years’ worth of research advantage over the United States.

The controversy regarding the ethical issues of embryonic stem cell research impacts the entire human population. Each individual in society has a susceptibility to contracting a disease that might possibly need the use of stem cells that can replace defective ones in the body. We have heard of a number of public figures that have suffered from diseases that could have been resolved through the use of embryonic stem cells. The late former President Ronald Reagan suffered from Alzheimer’s disease and the late actor Christopher Reeve experienced spinal cord injury. Both of these individuals are prime examples of people who could have benefited from the results of embryonic stem cell research. Stem cells may be cultured and manipulated to differentiate into specific types of cells such as astrocytes or brain cells for Alzheimer’s patients and neural cells for patients with spinal cord injury. However, nothing has been done since 2001 because the federal government has put a hold on any research activities that involve stem cell manipulation and experimentation.

The possible medical advantages of employing stem cells prevail over the claimed ethical issue of using “spare” embryos and the lack of respect for the embryo. This ethical concern is associated with the possible future demand for embryos once this cellular technology is determined to be successfully therapeutic. Embryos might later be treated as therapeutic materials or commodities instead of living beings at their initial stages. It should be understood that surplus embryos are generally kept in a deep freezer for storage until further use. A small portion of these embryos is currently being used for research purposes. As for the rest of the embryos that are left behind in the freezer, these are kept until another batch of embryos arrives and is scheduled for the same maintenance in cold storage. However, it should be noted that freezer space will never be unlimited for all times, and more than expected, there is usually a need to discard some of the older frozen embryos in order to give way to the fresher embryos that will be stored in the freezer.

From the scientific point of view, it is better to make use of these embryos than just keep them in the freezer because eventually, these embryos will be taken out of the freezer, thawed out and discarded, because there is a need for freezer space for the fresher embryos to stay in. These surplus embryos which are destined to be discarded have three possible routes for use. Surplus embryos may be given to an infertile couple who will more than likely appreciate the donation because they will have a chance of having their own baby. Surplus embryos may also be submitted to research laboratories so that these may be put to use for biomedical experimentation and breakthroughs. Another route wherein the surplus embryos may proceed is to submit these to research laboratories that aim to augment technologies and treatment regimens on assisted reproduction. Surplus stem cells may also be submitted to specific research laboratories that are focused on the production of more embryonic stem cells.

Conclusion

A significant number of researchers and scientists in several countries have shown their competence and proficiency in performing assisted reproduction technologies for the past few decades. The submission of spare embryos to these laboratories may therefore enhance their capabilities in improving current assisted reproduction treatments because they will have access to more embryos that may be treated as technical cases for fine-tuning of their techniques. It is actually better to test a new modification of assisted reproductive technology using spare embryos than to try this out in an actual pregnancy case in the hospital.

References

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Brown T. Gene Cloning And DNA Analysis: An Introduction. Los Angeles: Blackwell Publishing Limited, 386 pages, 2006.

Furch L and W Hoffman W. The Stem Cell Dilemma: Beacons Of Hope Or Harbingers Of Doom? New York: Arcade Publishing, 352 pages, 2008.

Hug K. “Sources Of Human Embryos For Stem Cell Research: Ethical Problems And Their Possible Solutions.” Medicina (Kaunas) 41(2005): 1002-1010.

Suzanne H, Lebacqz K and L Zoloth L. The Human Embryonic Stem Cell Debate: Science, Ethics, and Public Policy. Boston: The MIT Press, 288 pages, 2001.

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Wobus AM and KR Boheler. “Embryonic Stem Cells: Prospects For Developmental Biology And Cell Therapy.” Physiological Reviews 85(2005):635-678.