Problems with Embryonic Stem-Cell Research

Recently in the scientific world, the field of embryonic stem cell research has become a popular topic and has been the subject for many heated debates. Experts in the field of stem cell research promise that this will be the future of medicine; that stem cells will be the cure to all the debilitating diseases and afflictions of today, such as Alzheimer’s disease, heart disease, cancer and nerve damage. The truth about embryonic stem cell research is that it is not as hopeful and as revolutionary as it seems. Many problems that will negate the use of stem cells will and have already begun to arise, especially in areas concerning health risks to the patient, opportunity costs and human rights (Condic 803). Taking into account all the problems and risks that research on embryonic stem cells will bring about, the only solution is to terminate all research it before it causes permanent consequences that will affect all of society.
The central concept of stem cell research is the stem cell’s unique ability to reproduce for an indefinite amount of time and its ability to differentiate into any type of cell in the body, such as a muscle cell or a liver cell. This is unlike normal cells in the body, which can divide for only specific amounts of time and remain a single cell type, for example, a muscle cell remains a muscle cell and a liver cell remains a liver cell (Kumar 1-2). Although this concept sounds promising, the idea of applying embryonic stem cells in an attempt to cure major diseases has many flaws and there are many hurdles that science must overcome before embryonic stem cells could be of any use in medicine.
Scientists obtain embryonic stem cells by harvesting them from human embryos. The procedure after harvesting consists of cultivating the harvested stem cells in a laboratory, inducing them to divide, and later differentiating into the required cells. With the hopes of curing the patient’s afflictions, these newly grown cells would then be transplanted into the patient. With this approach come major problems such as the formation of tumours, which is caused by the distinguishing trait of stem cells. Because stem cells are able to divide for an unlimited amount of time, it has been found that the cells will not know when to stop dividing and they will continue to divide even after being transplanted into the patient (Herold 48). This form of treatment is counterproductive, as uncontrollable cell division will produce tumours and potentially cause cancer, which is one of the ailments that stem cell research promises to cure.
Another health problem that treatment with embryonic stem cells can cause is tissue rejection. As is the case with current organ transplantation procedures, embryonic stem cells are harvested from many people all who possess a unique set of genes; therefore, the stem cells are not genetically matched for each patient (Herold 48-49). The difference in genetics causes the body to reject the tissue and the immune system begins to attack the transplanted tissue like it would a virus or bacteria in an attempt to remove the perceived threat. To avoid the implanted tissues being rejected by the body, doctors must prescribe immune suppression drugs that must be taken for the remainder of the patient’s life, even with these drugs the tissue may still be rejected and will cease functioning (Bhimji).
A suggested solution to the problem of tissue rejection in embryonic stem cell transplant patients is therapeutic cloning. The procedure to therapeutically cloning a stem cell involves removing the nucleus of an embryonic stem cell, after this step the cell will no longer have any genetic information. Then the cell is fused with a non-embryonic cell from the patient. Afterwards, when the cells are induced to divide it produces a line of cells that are suitable for transplant. Since these cells have the same DNA as the patient there is no chance for rejection (Herold 49).
While this may be a solution to the problem of stem cell rejection, it causes a whole new range of problems and obstacles. As therapeutic cloning and reproductive cloning only differ in the final use of the embryo it is a very real possibility that therapeutic cloning could be abused to produce reproductive cloning, which most experts agree should be avoided at all costs. To avoid reproductive cloning extremely strict rules would have to be established, and even then there would be no guarantee that therapeutic cloning would not be taken advantage of in other parts of the world (Antoniou 398).
Along with the risks that are associated with therapeutic cloning there is a large opportunity cost associated with it as well. Cloning is a very ineffective process that involves the use of, and the waste of many eggs. This makes the process of therapeutic cloning very time consuming, and costs of therapeutic cloning very high. Considering the risks and complications of embryonic stem cells these resources could be spent elsewhere on other more promising treatment areas (Antoniou 398).
A major problem with embryonic stem cell research concerns the ethics of using human embryos for stem cells and then discarding them afterwards. It is widely believed that it is immoral to kill a person even though it could save another person’s life (Cohen 59-64), but even so eighty-four percent of clinics discard embryos, and there are millions of embryos that are discarded in the United States (Herold 36). As it is stated in various laws in numerous countries, people are protected from being forced into dangerous scientific studies; this applies especially to vulnerable members of society. The definition of a vulnerable person is having no power, having inadequate intelligence, having inadequate education or having an inability to protect themselves. Using these criteria it is clear that vulnerable members of society will include children, pregnant women and fetuses, but it also should be obvious that it must include embryos as well. Because embryos are easy to obtain and are unable to consent they should be especially protected (Napier 497-499). This protection should assure that embryos are not used in stem cell research, which would consequently abolish the studies.
Supporters of embryonic stem cell research argue that the embryo cannot be considered a vulnerable person, or even a person at all; therefore, it should not benefit from protection and should be used in research. Embryos and fetuses are very similar, they only differ in one aspect; fetuses are attached to the uterus whereas embryos are not. Being attached to the uterus does not make the fetus more vulnerable; it can actually make the foetus less vulnerable than the embryo, and in more need of protection (Napier 502-506).
Excluding embryos in the classification of vulnerable human beings while including fetuses is illogical. Every embryo has the potential to become a human being, and many people believe that life starts with the embryo, or even sooner such as fertilization when the genetic code is established (Cohen 62). It is also logical to assume that people remain the same person all throughout their lives, and proceed directly from one stage to the other, never changing identity. Adults are the same person as when they were infants, and logically this can be expanded to say they are the same as when they were fetuses, and in the beginning as embryos. Using this logic it is clear that embryos are people and need protection.
In conclusion further research into uses of embryonic stem cells is a fruitless pursuit, in which the harm and problems caused to society will outweigh any benefits that it could have. The arguments for embryonic stem cell research contain distorted and unethical views, which John Wyatt from the Royal Free Hospital in London, England sums up in these few words, “The redefinition of human embryos as mere biological material, and ‘totipotent stem cells’ in order to allay public concerns, smacks of semantic trickery rather than responsible debate (Antoniou 397).”
Embryonic stem cell research poses a severe threat to the health of patients receiving these treatments, whether it is from tumours or tissue rejection. It also is a menace to society in general, by potentially introducing a means for reproductive cloning, or by discarding human embryos like they are worthless. The field medical research should be heading in a more favourable direction, one that focuses more on safe and ethical procedures to achieve its goals.

Works Cited

Antoniou, Michael. “Embryonic Stem Cell Research – the Case Against..” Nature medicine 7.4 (2001): 397. Web. 25 Nov. 2011.
Bhimji, Shabir. “Transplant rejection.” U.S. National Library of Medicine. 14 June 2011. Web. 26 Nov. 2011.
Cohen, Cynthia B. Renewing the Stuff of Life. Oxford ;New York: Oxford University Press, 2007. Print. 26 Nov. 2011.
Condic, Maureen. “Unlikely Stem Cell Therapies.” Nature neuroscience 10.7 (2007): 803-. Web. 25 Nov. 2011.
Herold, Eve. Stem Cell Wars. New York: Palgrave Macmillan, 2006. Print. 26 Nov. 2011.
Kumar, Sachin, and N. P. Singh. “Stem Cells: A New Paradigm.” Indian Journal of Human Genetics 12.1 (2006): 4-10. Web. 12 Nov. 2011.
Napier, Stephen. “A Regulatory Argument Against Human Embryonic Stem Cell Research.” Journal of Medicine & Philosophy 34.5 (2009): 496-508. Web. 26 Nov. 2011.

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The Legal History and Ethics of Stem Cell Research

An interesting aspect of stem cell research is how politically charged it was from its very beginning. Originally born into a conservative playing field, the bounds on stem cell research were never as open as they are now, having been suppressed by political opinion for several decades. Numerous accounts of voting to support stem cell research were blocked by individual opinions of people with the influence to do so. Today, stem cell research is more open and accepted, due to technological advancements, but I think more importantly, a changing political mood. But this freedom allows for more ambitious trials and research to take place, so it is important to allow the field to progress scientifically, without befalling to scandals or fraud like other breakthrough medical applications have in the past.
My primary source is an overview of the current state of stem cell research written by Roger Barker, Professor of Clinical Neuroscience and Honorary Consultant in Neurology at the University of Cambridge and at Addenbrooke’s Hospital (Roger Barker pg.1). Barker has been in his current position for more than ten years with his main interest being neurodegenerative disorders, one of the main proposed applications for stem cell research. He wrote this article in 2013, so the opinions he brings up are very current and relevant to the current status of stem cell research.
Barker gives a brief introduction reciprocating the optimistic potential of stem cell research often seen today. However, he quickly makes a point that stem cell research is highly subject to unchecked optimism and claims that go beyond the evidence given by clinical trials. He says this because there are many “desperate patients and … families [who] will often seek to try any new therapeutic intervention” (Barker pg.1). Barker notes that stem cell transplants have been effective in the field of hematology, namely, using transplants to replenish bone marrow of patients who were treated for cancerous blood disorders (Barker pg.1). However in the case of neural cells, stem cells need to meet a higher standard to be effective, which Barker says none have fully met yet.
In the end of his discussion, Barker says that the field of stem cell research is consistently moving forward every year, as many well-designed trials are being planned and undertaken. Despite this, no trials have shown a level of effectiveness suitable for “mainline” therapies (Barker pg.3). He also warns that the rush to get from the laboratory to the clinic for advancement of therapies could derail the whole field “by a disastrous result of an ill thought out treatment” (Barker pg.3). If that were to happen, then the therapies currently being developed by sound scientific procedures would be ruined by the confusion caused by “the unproven, commercially driven cells of today” (Barker pg.3).
From this article, it seems that stem cell research is a good area to see the difference between therapeutic optimism and therapeutic nihilism. Therapeutic optimism is the notion that modern therapeutic research has the ability to treat even some of the most complex illnesses. Patients with incurable illnesses tend to look at these “promising” therapies with the hope that they will offer a solution. Contrary to that, therapeutic nihilism is the belief that while no better therapeutic solutions currently exist, the current developing therapies hold little to no promise either. For example, if stem cell research suffered some infamously bad treatment making its way into the spotlight, then the general population may feel that stem cells are not the best way to tackle issues such as neurodegenerative disorders, even though it seems there aren’t any significantly more effective treatments to date.
The article also talk about the issue of medical ethics and the standards that we should impose on clinical trials before a new therapy is deemed acceptable. One of the biggest issues scientific medicine has dealt with is clinical ethics. After the French Revolution, the focus of medicine fundamentally shifted from being patient-centered to research-centered. Such a focus has led to times where the interests of the researcher take precedence over the well-being of the patient. During World War II, the experiments done by Nazi medicine displayed one of the most horrific instances of this, but since then, bioethics has become an increasingly important topic for the global scientific community.
One of the main goals of my paper is to describe the political context of stem cell research throughout its development. Modern stem cell research was born right around the same time as pro-life vs. pro-choice debates arose. Since one of the main sources for stem cell research was embryonic tissue (whether it be donated by patients or created in the lab), the research met heavy resistance from conservative political forces, up until the early 21st century. The issue raised by Robert Barker about commercialized stem cells might not be entirely due to the forces of capitalism, but perhaps due to the fact that publicly funded stem cell research was suppressed for several decades. Secondly, I will discuss the implications of the issue of commercialization. I will look at some events that display how ulterior motives can influence the science of medical research, and how the response is handled by the scientific community and the public.
The history of stem cell research is fairly recent. In the early 1900’s European researchers realized the various types of blood cells originated from the same “stem” cell and the idea of these cells was postulated for some time. But it was not until 1963 when researchers Ernest McCulloch and James Till quantitatively described the self-renewing nature of cells in the bone marrow of mice (History of Stem Cell Research pg.1). This concrete evidence helped kick start the research movement. However, the research would find itself gaining steam in a linear fashion. Recall that in 1973, the famous Roe v Wade court case rules that abortions are fully legal during the first two trimesters of pregnancy. This highly political issue was counteracted by members of Congress, who feared that medical research would exploit the increase of aborted embryos and fetuses for experiments (Embryo and Stem Cell Research pg.1). In response to Roe v Wade, the Department of Health and Human Services (DHHS) placed a temporary moratorium on living embryo research. Congress itself placed a temporary restriction on federally funded clinical research on embryonic tissues, which by nature also extended to the practice of in-vitro fertilization (Embryo and Stem Cell Research pg.1). in 1975, the DHHS lifted the ban on research, but continued to restrict funding. With this political blockade in place, early stem cell research had limited options. Research was not killed however, as the ban was only on embryo research for therapeutic purposes. And so, basic research with living embryos continued, but it was restricted to a manner in which direct and more effective therapies could not be exercised.
Throughout the rest of the 20th century, government institutions continued to stifle embryonic research. In 1987, the National Institute of Health requested using transplants of fetal neural cells for Parkinson’s disease. The DHHS withheld their approval, with the Assistant Secretary of the Health claiming that the research would induce women ambivalent about abortion to have one (Embryo and Stem Cell Research pg.1). In response, the NIH created the Human Fetal Tissue Transplantation Research Panel, which voted 18-3 for approval of using fetal tissue. They argued that the use of the tissue to treat disease was morally distinguishable from the act of abortion. However, the DHHS Secretary decided to ignore this vote and honor the opinion of three conservative panel members who voted against fetal tissue use. The moratorium on embryonic tissue was extended indefinably at this point.
Numerous attempts were made to have the ban lifted, but it took the influence of President Clinton in 1993 to have it done. The NIH Human Embryo Research Panel determined (by an even narrower margin than before) that the creation of embryos specifically for research would not encourage abortions, and therefore was permissible. However, immense public outcry moved Clinton to override the panel’s decision. In 1996, Congress again banned federal funding for embryo research with The Dickey-Wicker Amendment. But because they didn’t specify if that applied to cells already derived from embryos, the NIH legal department ruled that it was okay to fund research with existing stem cells, but not fund the process of deriving stem cells themselves. That ability was still only allocated to the private sector. President Bush issued an executive order in 2001 that prohibited the funding of stem cell research using any cell lines derived after August 9, 2001, citing that there were already more than 60 cell lines available to do research on (Timeline of Major Events in Stem Cell Research Policy pg.1). This statistic was based off the NIH registry, and in reality, only 21 lines were available for research and very few of those were suitable for human use (Legal and Political History of Stem Cell Science pg.1). In 2005, both the House and the Senate passed the Stem Cell Research Enhancement Act, which would allow for stem cells to be derived from embryos that were created for, but not used for, in-vitro fertilization. But yet again, President Bush opposed this by vetoing the bill, and with a 235-193 vote by the House, the vote needed to override the veto was not passed. The exact same thing happened again with a revision of the bill in 2007.
Up to his point in time, embryonic research was stifled again and again by largely conservative opinions about human tissue. This opinion was felt by both political bodies and the public. The ability for the government to regulate medical research was exercised very strongly in the late 20th century and early 21st century. However, with the inauguration of President Obama, embryonic tissue research saw a major shift in support.
Within two of months of inauguration, President Obama issued an executive order in opposition to that of President’s Bushes, declaring that the NIH “may support and conduct responsible, scientifically worthy human stem cell research, including human embryonic stem cell research, to the extent permitted by law” (President Obama in Legal and Political History of Stem Cell Science pg.1). This was meant to allow the NIH to develop the guidelines for stem cell research, which they did several months later in July, 2009. A month later, a group of plaintiffs led by somatic (different from embryonic) stem cell scientists James Sherley and Theresha Deisher filed a suit against the NIH, claiming the new federal funding for embryonic research was violating the Dickney-Wicker Amendment. Chief Judge Royce Lamberth of the Washington D.C. District Court initially dismissed the case (Sherley v. Sebelius), claiming the plaintiffs were not affected by the new laws. However, the plaintiffs appealed to the District Court of Colombia and Judge Lambert granted their initial request to stop funding embryonic research, after the case was sent back to him in 2010. But then, the District Court of Appeals blocked Lamberth’s injunction to stop the funding, allowing it to continue while the case remained unsettled. In 2011, Lamberth ruled that the government could continue to fund embryonic stem cell research, even though the restriction was lifted a year ago by the Court of Appeals (Legal and Political History of Stem Cell Science pg.1). Bringing us the near present day, Sherley v. Sebelius was declined to be heard by the Supreme Court in 2013, and Stem Cell Action Coalition spokesperson Bernard Siegel noted that “this [was] a major victory for scientifically and ethically responsible innovative research” (Siegel in Legal and Political History of Stem Cell Science pg.1).
Although now enjoying a more politically liberal embrace, political suppression was not the only key issue of stem cell research. As with many medical treatments that move toward the limelight of mainstream therapy and applications, there is the concern over commercialization and how the presence of an “industry” can change the way a medical innovation is viewed. As Robert Barker said in his article, a trial with largely ill consequences could significantly harm the research field. This has happened before in the medical/pharmaceutical industry. In the 1950’s/1960’s, a German company developed an experimental drug named Thalidomide and quickly realized it was a powerful but non-lethal sedative. After a very rudimentary and non-systematic trial of efficacy, the drug was released to the public. A few years later, people began connecting Thalidomide to a number of symptoms, including birth defects, but its use continued. At this point in time, the Food and Drug Administration was very weak, and in fact, before Thalidomide was approved in the United States, 20,000 people had already been given samples of the drug by physicians (Lecture 9.1). However, in 1961 the news came out that Thalidomide was being withdrawn in Europe, and this had a deep impact on the trust that the public put into modern medicine. This is the kind of scenario that Barker fears, where a hasty implementation of stem cell therapy could have significant backlash, and destroy support for the research. Even more worrisome is the fact that there are many people who are willing to try ‘promising’ therapies to help aid them. This is the core component of therapeutic optimism, wherein people who don’t know anything technical about medicine still assume that whatever it produces is to benefit the patient regardless. However, that notion has been questionable ever since the French Revolution and the shift of medicine from being patient-centered to research-centered.
One of the most noteworthy ethical breaches in stem cell research was committed by Professor Hwang Woo-Suk. Woo-Suk was a researcher at Seoul National University in South Korea. During 2004-2005, he garnered international fame among the community of stem cell research for creating 11 new stem cell lines via somatic cell nuclear transfer. In 2009, Woo-Suk was convicted for illegally using research funding to buy human eggs, although there were no legal restrictions in South Korea for how eggs had to be acquired. However, majority of the women he procured eggs from had not given valid, informed consent. In addition to that, some of his patients were infertile and agreed to donate any excess eggs leftover from their fertility treatment. Woo-Suk and his team assigned quality ratings to these eggs, keeping the higher-quality ones for research and using the lower-quality eggs for the patient’s own treatment. These actions were in clear breach of the Korean Bioethics and Safety Act, and led to Woo-Suk’s work being revoked and discredited. (The Cloning Scandal of Hwang Woo-Suk pg.1). Fortunately for the scientific community, Woo-Suk’s fraud was shrugged off, in part because six months later, a new method was shown to effectively manipulate skin cells into what very closely resembled embryonic cells, which shifted focus away from nuclear-transfer research altogether. Another saving grace of this incident was that Woo-Suk was exposed by a member of his own team, showing the ability of the scientific community to self-regulate. However, this is still an example and reminder of how medical ethics is not a problem of the past.
Today, opinions on stem cell research can be divided into three main groups. There are those that think stem cell research is morally okay, as it focuses mainly on finding therapeutic treatments for people with incurable disorders. There are those that see any rudimentary form of life as still being life, and therefore it must be respected by the standards we place on sentient human beings. However, due to constantly evolving technology and techniques, there are those who might argue that somatic stem cells are permissible to use while embryonic cells are not. Recall that somatic cells are cells that can be taken from adult cell structures and undergo a process of induced pluripotency, meaning that scientists can take these cells and reprogram them to resemble stem cells. However, also remember what Barker said about the current state of stem cell research. That is, there is yet to be a form of stem cells that can be produced and fully function as neural cells. I think that is one of the most interesting topics of stem cell research though, as it aims to solve a problem that we have yet to find a solution.
I believe that the recent support toward stem cell research is a positive turn of events. Science does need to have limits and regulation; otherwise in cases like Woo-Suk and Thalidomide, scientific medicine can lose sight of what is fair and acceptable for the patient in pursuit of other prospects. But even with the case of embryonic cells aside, stem cell technology is consistently advancing, with induced pluripotency making major leaps and bounds. Another good idea for the efficacy of clinical trials that is also mentioned by Barker is that trials should not be performed a population of patients who paid for the treatment. This raises serious ethical issues as to whether or not scientific medicine intends to benefit itself through financial gain, or the public as a whole. Certainly I would like to believe the latter as would many others, and that is why publicly supported studies and trials are important to development of stem cell therapy. Furthermore, to avoid the pitfalls of therapeutic optimism that have happened before, it is important for the scientific community to remain systematic and rigorous so that in the future, any mainstream stem cell therapy can be trusted, reliable, and effective.
Works Cited
Barker, Robert. “Stem Cell Therapies and Neurological Disorders of the Brain: What Is the Truth? | Europe’s Stem Cell Hub | EuroStemCell.” EuroStemCell. N.p., 24 Apr. 2013. Web. 20 Mar. 2014. .
“Brief History of Stem Cell Research.” Science Progress Timeline A Brief History of Stem Cell Research Comments. N.p., 16 Jan. 2009. Web. 20 Mar. 2014. .
“The Cloning Scandal of Hwang Woo-Suk.” Stem Cell Bioethics. N.p., n.d. Web. 20 Mar. 2014. .
“The Commercialization of Stem Cells: Promises and Public Concerns.” Stem Cell Bioethics. N.p., n.d. Web. 20 Mar. 2014. .
Hadenfield, Manal. “Reprogramming: How to Turn Any Cell of the Body into a Pluripotent Stem Cell | Europe’s Stem Cell Hub | EuroStemCell.” EuroStemCell. N.p., 24 Dec. 2012. Web. 20 Mar. 2014. .
“HISTORY OF STEM CELL RESEARCH.” Boston Childrens Hospital. N.p., n.d. Web. 18 Mar. 2014. .
“Legal and Political History of Stem Cell Science.” Stem Cell Bioethics. N.p., n.d. Web. 20 Mar. 2014. .
“Timeline of Major Events in Stem Cell Research Policy.” Timeline of Major Events in Stem Cell Research Policy:. N.p., n.d. Web. 19 Mar. 2014. .
Wertz, D. C. “Embryo and Stem Cell Research in the United States: History and Politics.” Nature.com. Nature Publishing Group, June 2002. Web. 19 Mar. 2014. .

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The Government Should Fund Embryonic Stem Cell Res

Millions of people die every year from diseases and accidents; the nightly news is filled with reports about the devastating effects of cancer, horrific accidents, and disasters that leave people disfigured or paralyzed. Embryonic stem cell research is a part of biomedical science and has the potential to ease the suffering of sick people by curing diseases and defects, creating organs and tissue for patients needing transplants or skin grafts, regenerating axons in spinal cord injuries, and creating new treatments, drugs, and immunizations. However, America’s government does not support this research to an extent that would make a difference in medicine; only a few stem cell lines are authorized, and federal funding is minimal. The government should support embryonic stem cell research by educating the public, increasing federal funds, and easing restrictions.
Public Education
Stem cell research began in 1956 when Dr. E Donnall Thomas performed the first bone marrow transplant (“Adult stem cells are not more promising,” 2007). Since that time, research has evolved into obtaining cells from a variety of tissues. According to stem cell research professors, Ariff Bongso and Eng Hin Lee (2005), “Stem cells are unspecialized cells in the human body that are capable of becoming cells, each with new specialized functions” (p. 2). Stem cells are in various adult tissues, such as bone marrow, the liver, the epidermis layer of skin, the central nervous system, and eyes. They are also in other sources, such as fetuses, umbilical cords, placentas, embryos, and induced pluripotent stem cells (iPSCs), which are cells from adult tissues that have been reprogrammed to pluripotency. Most stem cells offer multipotent cells, which are sparse and can only produce a limited number of other tissues. Pluripotent cells, on the other hand, offer large amounts of cells, and each one of these cells can potentially form over 200 cell types (Deem, 2009). Human embryonic stem cells (hESCs) are pluripotent and are obtained from the inner mass of a 4-5 day old human blastocyst that consists of approximately 100 cells (“Stem cell research,” 2009).
Stem cells are grown on Petri dishes in a laboratory and are never implanted in a woman’s uterus. These cells can be used to create stem cell lines that can grow indefinitely under optimal conditions (“Stem cells and diseases,” 2011). Embryonic stem cells can be obtained from existing stem cell lines (any group of cells that came from the same original embryo), aborted or miscarried embryos, unused in vitro fertilized embryos, and cloned embryos created from somatic cell nuclear transfer (the nucleus from an unfertilized egg is removed and replaced with a nucleus from an adult stem cell). This technique would be used for therapeutic cloning, which could grow organs or skin grafts for patients. However, the only research that is federally funded are a few embryonic stem cell lines created from unused embryos at in vitro fertilization (IVF) clinics before 2001 (Dunn, 2005; “Embryonic & fetal research laws,” 2008; Therapeutic cloning, 2009). These lines are not enough to allow scientists to fully explore and take advantage of potential findings.
Limited government support may have also contributed to increased political and religious controversy, which has left prospective socio-economic benefits unrealized. Educating the public could dispel misconceptions and may lead to the opening of more labs and discovery of new medications and immunizations, which in turn could create jobs.
Another misconception is that the scientific community is divided over the issue of stem cell research. William Neaves, president and CEO of Stowers Institute for Medical Research in Kansas City, Missouri noted that support for all types of stem cell research to include somatic cell nuclear transfer is overwhelming. He also stated, “The fact that a handful of scientists may oppose research with early stem cells does not reflect a division of scientific opinion on this issue.” Current organizations that support embryonic stem cell research include the American Medical Association, the National Medical Association, the Association of American Medical Schools, the Institute of Medicine of the National Academy of Sciences, and the National Academy of Sciences (“Adult stem cells are not,” 2007).
Opponents also argue that life begins at the moment of fertilization and to use embryos in research is inhumane (Ham, 2001, para. 3). According to the University of Michigan, the blastocysts used for stem cell research are so young that they have not begun to differentiate into various organs and tissues; none of the seven organ systems required for life are present. Even more compelling is the fact that there are more than 400,000 frozen embryos in IVF clinics and thousands are discarded as medical waste every year. These embryos could potentially be given to couples seeking fertility treatment, but few parents choose to do this; less than 200 cases of children born from donated embryos has been documented since 1997 (“Stem cell research,” 2009). There are also numerous people who are unsure as to what state of development constitutes life, so they believe that since these embryos would be destroyed eventually and because they have the potential to save millions of lives, embryonic stem cell research should be supported by the government (Ham, 2001, para. 3).
Another argument made by opponents of hESC research is that human adult stem cell (hASC) research is superior to hESC research, because it has been conducted far longer and has produced results unlike the latter, which has caused cells to migrate through the body and produce tumors (Deem, 2009). Supporters, such as, Dr. Zach Hall, head of the National Institute for Neurological Disorders and Stroke and president of the California Institute of Regenerative Medicine, argues that adult stem cells may be politically advantageous but they do not grow well in cultures, their properties have changed somewhat so their ability to make specialized cells is restricted and they are rare so cures are restricted (“The difference between,” 2010, para. 10, 11).
Still others are convinced that research in all areas must be done in order to progress. According to the Genetic Science Learning Center (2011), a number of experts believe that studying embryonic, adult, and induced stem cells is the only way to advance, and Bongso and Lee (2005) similarly stated, “Both embryonic/fetal and adult stem cells are equally important and research into both types must be enthusiastically pursued…” (para 10; p. 1). Studying blastocysts with as much fever as other areas of stem cell research could provide scientists with insight into how these cells transform into a vast array of specialized cells, the origins of birth defects could be discovered and/or corrected through drug discoveries, and tissues and organs could be replaced. Prospective treatments and cures from pluripotent cells are numerous and could include Parkinson’s disease, ALS, spinal cord injuries, burns, heart disease, diabetes, and arthritis (“Stem cells and diseases,” 2011). However, these medical breakthroughs may never become reality without educational or monetary support from the Federal Government.
Increasing Federal Funds
In 2010, the National Institutes of Health (NIH), an agency of the United States Department of Health, allocated 414.4 million for non-embryonic stem cell research and only 165.2 million for embryonic stem cell research (“NIH stem cell research,” 2011). The fact that adult stem cell research has made more progress could be attributed to the 250 million more in funding it receives every year. Appropriate funding in all areas of stem cell research could increase resources available and make way for advancements.
Opponents state that increasing federal funding for hESCs would be a waste of taxpayer money because no results have been produced, and it would slow research in other areas that have made progress (May, 2006). Currently, the NIH does not allow any research to be conducted in a laboratory where federally funded stem cells are located. This has resulted in the creation and maintenance of separate laboratories when private or state funds are used. This restriction is wasteful and time-consuming. Loosening restrictions could unite moneys from all sectors ensuring continuity and standards are upheld, easing minds of opponents and eliminating the bureaucracy associated with complex rules and regulations, which hinders progress on all levels (“Center for American Progress,” 2009, para. 8-9).
Easing Restrictions
Finally, the government should ease restrictions on embryonic stem cell research because most of the initial authorized stem cell lines from President Bush’s executive order do not contain the genetic material needed to conduct research that could find cures for “disease-causing genetic defects” [race-specific diseases carry certain genetic markers] or they have been contaminated with mouse feeder cells, which make them unusable for studies involving human patients. (“Stem cell research,” 2009; Webb, 2009). Mouse feeder cells are mouse skin cells that have been treated so they will not divide. These cells are placed in the bottom of Petri dishes and provide both nutrients and a surface for the embryonic stem cells to adhere to. These lines cannot be used in human trials because there is a risk of transmitting diseases (Dunn, 2005; “What are embryonic stem cells,” 2010).
President Barack Obama attempted to fix this issue in 2009 when he signed an executive order to loosen some of the restriction and increase funding. During his speech, he appealed to both sides of the issue by ensuring that the government would pursue this through strict guidelines to guarantee there would be no misuse or abuse. He also stated:
“When governments fail to make these investments, opportunities are missed. Promising avenues go unexplored. Some of our best scientists leave for other countries that will sponsor their work. And those countries may surge ahead of ours in the advances that transform our lives” (para. 3, 9).

This decision might have opened the doors for advancements that would have eased the suffering and made life better for so many. However, Obama’s decision was short-lived when District Judge Royce Lamberth granted a preliminary injunction on hESC funding on the grounds that it violated the 1996 Dickey-Wicker Amendment prohibiting the use of federal funds to destroy embryos (Fuller, 2010).
This has brought scientist back to square one, diminishing progress and stalling potential scientific discoveries. Currently, only 16 states allow some form of hESC research to be conducted and each state allows various degrees of research on fetuses and/or embryos (“Embryonic & fetal research laws,” 2008). Inconsistencies between state and federal laws coupled with “continued legal wrangling” may lead many scientists to pursue other fields or to look at possible prospects in other countries, which might take jobs and money away from the economy and keep new breakthroughs out of scientific, technical, or medical journals (Fuller, 2010). Without peer-reviewed literature, the United States could lose its competitive edge in medical technology and developments, such as iPSCs. Richard Deem, an evangelical Christian who works as a molecular biologist in Crohn’s disease, argued that the use of iPSCs eliminates the need for embryonic stem cells and avoids the high cost associated with it. Conversely, Neaves suggested that scientists have learned how to stimulate a patient’s own cells to behave like embryonic stem cells, and if research into the mechanism of differentiation of cells is not pursued, advancements in the field of iPSCs would be slowed. Neaves continued his argument by making several analogies in other areas of science. He stated that adult stem cell research has been conducted far longer than embryonic stem cell research, but it does not make it a better option, and if research with bone marrow transplantation had been outlawed 50 years ago, there would have been no list of adult stem cell cures to show people (Deem, 2009; “Adult stem cells are not,” 2007). The key to success is not to outlaw or dispel potential advancements but to use one area of research to further progress in another in a sensible and responsible manner.
The possible benefits from increased federal funding, public education, and loosening restrictions should not be ignored. This could change the quality of life for people of all political, religious, and socio-economic backgrounds. How could providing jobs, lowering costs, and easing the suffering of millions be a bad thing?
Christopher Reeve, who suffered a spinal cord injury as a result of a horseback riding accident, believed that all areas of stem cell therapy should be pursued. He had faith that one day he would be able to function normally because of stem cell therapy (Mader, 2010, p. 584). He did not live to see the government fully support embryonic stem cell research, but he and several other influential people, such as, Michael J. Fox [who is afflicted with Parkinson’s disease], and Brad Pitt, became the driving force behind convincing the voters in California to accept Proposition 71, which allocated state money for embryonic stem cell research (Dunn, 2005). Although this was a step in the right direction, it was not enough to make a serious impact.
Arguments regarding reasons why embryonic stem cell research should not be federally funded or why restrictions should not be eased will continue to be a controversial issue; however, these arguments will also bring to light all the possibilities that hESC research has to offer. Without support from the Federal Government, negative attitudes may continue to thwart legislation, funding may dry up, and restrictions may affect all areas of stem cell research. Obama said it best when he stated, “… the potential it offers is great, and with proper guidelines and strict oversight, the perils can be avoided” (2009, para. 6).

References
Adult stem cells are not more promising than embryonic stem cells. (2007). In J.
Langwith (Ed.), Opposing Viewpoints. Stem Cells. Detroit: Greenhaven Press. Retrieved from http://padme.cochise.edu:2067/ic/ovic/ViewpointsDetailsPage/ViewpointsDetailsWindow?displayGroupName=Viewpoints&prodId=OVIC&action=2&catId=&documentId=GALE%7CEJ3010453228&userGroupName=sier28590&jsid=4dd17d7c10103c97cfdac92c13186ac8
Bongso, A., & Lee, E. H. (2005). Stem Cells: Their definition, classification and sources. Stem
cells: From bench to bedside. (pp. 1-13). Singapore: World Scientific.
Center for American Progress. (2009, March 9). Eight reasons to applaud action on stem cells. Center for American Progress. Retrieved March 17, 2011, from http://www.americanprogress.org/issues/2009/03/stem_cell_action.html
Deem, R. (2009, March 31). What is wrong with embryonic stem cell research? In Evidence for
God. Retrieved March 19, 2011, from http://www.godandscience.org/doctrine/stem_cell_research.html
Dunn, K. (2005, April 1). NOVA | The politics of stem cells. PBS: Public Broadcasting Service. Retrieved April 20, 2011, from http://www.pbs.org/wgbh/nova/body/stem-cells-politics.html
Embryonic and fetal research laws. (n.d.). NCSL Home. Retrieved April 15, 2011, from
http://www.ncsl.org/default.aspx?tabid=14413
Fuller, E. (2010, October 12). Stem cell exodus? The Christian Science Monitor. Business
section. Retrieved March 14, 2011, from ProQuest (2178980461).
Genetic Science Learning Center (2011, January 24). The stem cell debate: Is it over? Learn
Genetics. Retrieved March 14, 2011, from http://learn.genetics.utah.edu/content/tech/stemcells/scissues/
Ham, R. D., & Ph.D. (2001, June 19). PPI: Stem cell research: The case for federal funding by Rebecca Dudzik Ham, Ph.D. Progressive Policy Institute: Defining the Third Way. Retrieved April 20, 2011, from http://www.ppionline.org/ppi_ci.cfm?knlgAreaID=111&subsecID=140&contentID=3475
Mader, S. (2010). Selected material from Biology (tenth ed., pp. 159-584). New York, NY:
McGraw-Hill Companies, Inc. (Original work published 2001)
May, D. R. (2006). Governments should reduce support for embryonic stem cell research. In
J. D. Torr (Ed.), Current Controversies. Genetic Engineering. Detroit: Greenhaven Press. (2006). (Reprinted from, n.d.) (Reprinted from, 2005) Retrieved from http://padme.cochise.edu:2067/ic/ovic/ViewpointsDetailsPage/ViewpointsDetailsWindow?displayGroupName=Viewpoints&prodId=OVIC&action=2&catId=&documentId=GALE%7CEJ3010212255&userGroupName=sier28590&jsid=8dc67ab5291ffe37eae2cd312e12b925
NIH stem cell research funding, FY 2002-2010 [Stem Cell Information]. (2011, February 14).
NIH Stem Cell Information Home Page. Retrieved April 18, 2011, from http://stemcells.nih.gov/research

Obama, B., discoveries, w. w., prosperity, t. b., & humanity., b. f. (2009, March 9). Remarks of
the President-As Prepared for Delivery-Signing of Stem Cell Executive Order and Scientific Integrity Presidential Memorandum | The White House. The White House. Retrieved April 14, 2011, from http://www.whitehouse.gov/the_press_office/Remarks-of-the-President-As-Prepared-for-Delivery-Signing-of-Stem-Cell-Executive-Order-and-Scientific-Integrity-Presidential-Memorandum/
Stem cells and diseases. (2011, January 7). In Stem cell information, the National Institutes of
Health resource for stem cell research. Retrieved March 14, 2011, from http://stemcells.nih.gov/info/health.asp
Stem cell research. (2009). University of Michigan. Retrieved April 7, 2011, from
http://www.umich.edu/stemcell/
“The difference between embryonic, adult stem cells.” Host Robert Siegel. All Things
Considered. National Public Radio. 24 Aug.2010. Retrieved March 16, 2011, from http://www.npr.org/templates/story/story.php?storyId=129406274.
Therapeutic cloning. (2009). Collins English Dictionary – Complete & Unabridged 10th Edition.
Retrieved April 28, 2011, from Dictionary.com website: http://dictionary.reference.com/browse/therapeutic cloning

Webb, S. (2009). Stem cell research is suffering due to the lack of federal funding. In A.
Francis (Ed.), At Issue. Should the Government Fund Embryonic Stem Cell Research?. Detroit: Greenhaven Press. (2009). (Reprinted from, n.d.) (Reprinted from Science Magazine, 22 September 2006) Retrieved from http://padme.cochise.edu:2067/ic/ovic/ViewpointsDetailsPage/ViewpointsDetailsWindow?displayGroupName=Viewpoints&prodId=OVIC&action=2&catId=&documentId=GALE%7CEJ3010587207&userGroupName=sier28590&jsid=67271fc8c381f89007dff41cfd3813e6
What are embryonic stem cells? [Stem Cell Information]. (2010, September 13). NIH Stem
Cell Information Home Page. Retrieved April 14, 2011, from http://stemcells.nih.gov/info/basics

 

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Stem Cell Research: Should we legalize it?

Stem Cell Research: Should we legalize it?
I. Introduction and History
Is going against certain religious morals worth finding cures using experimental science? Many scientists are constantly trying to push the boundaries of science to find new things. This is especially true in the medical partition of experimental science. There are a great deal of scientists working everyday to find cures to today’s diseases and illnesses such as Aids, cancer, Parkinson’s, and Alzheimer’s disease. People live with these illnesses everyday of their lives, and the number of people with diseases rises day after day. Naturally people want to help others so they turn to science. Religious people don’t have a problem with trying to help people, but rather the method used for finding the treatments is what sparks the controversy.
Scientists have been doing research using plants from the time when medicine was invented. Many vaccines and other medicines have been created using plants, but nothing too big in the world of medical science. In the 60s two Canadian scientists discovered stem cells. A stem cell has “two important characteristics that distinguish them from other types of cells… they are unspecialized cells that renew themselves for long periods through cell division [and] they can be induced to become cells with special functions such as the beating cells of the heart muscle or the insulin-producing cells of the pancreas” (Stem Cell Basics 1). Since the discovery of stem cells, interest in them has grown exponentially. Many of the top scientists in the world believe that stem cells have the potential to cure many of today’s illnesses.
Research using embryonic stem cells is currently legal in the United States but “research can be conducted… [only] with private money” (Stolberg 2), it cannot be federally funded. A bill was also passed that stated human embryos cannot be created for the sole purpose of destroying them during stem cell research. President Bush vetoed bills trying to pass federal funding for stem cell research. Eventually President Bush made an address on television stating that he will not allow federal funding for new stem cells, but will fund research for previously obtained embryos from the past and he would allow private companies to fund the research themselves. President Bush compared “the decision about federal funding of embryonic stem-cell research to a decision to commit troops to battle” (Gibbs 1).
Stem cells have great potential but at the cost of going against the morals of many people. Research on stem cells has brought up a lot of questions. How wrong is the research if it is for finding cures to widespread diseases? Are embryos growing inside a lab the same as one inside a mother’s womb? “Is it O.K. to experiment on [them] if [they are] going to be destroyed anyway” (Gibbs 1)? Should scientists be able to play the role of God by changing the way a living organism was supposed to be? Even though some believe that stem cell research is morally wrong, and should be considered murder because scientists are destroying the beginning of a human being, the truth of the matter is stem cell research is beneficial for our society because it will help people cure diseases, and may in the future be able to create organs from scratch, helping all of the people waiting for organ transplants.
II. Argument against Stem Cell Research
One of the main arguments against stem cell research is that embryonic stem cell research kills growing humans during the research process. Embryonic stem cells are taken from aborted fetuses, which in turn generate conflicts between scientists and pro-life activists. Pro-life activists often mention the fact that “there are other, slightly less controversial means of culling the precious cell” (Reaves 2), but those cells don’t have the same liveliness and usefulness as those received from embryos. Many pro-life people also argue the point that “an embryo is a human life, not a piece of research material, [and] [from] a moral standpoint, it is unacceptable for people to destroy innocent human life for their own benefit” (Saltzman 1). When they bring up the fact that an embryo is a human life and it’s growing, people tend to side with them, even though scientists are doing it to potentially save lives.
Although embryonic stem cell research looks very promising there are alternatives to getting stem cells from embryos, for example adult stem cells. Pro-life activists are praising this new type of research. They believe that “federalizing fetal stem cell research will solve nothing morally because… it requires the destruction of human embryos and it feeds on abortion” (Saltzman 3). If we “find another source of stem cells …the moral problem goes away” (Saltzman 4), and everyone will be happy. But the problem with adult stem cells is that they are “marginally helpful to scientists, and do not show the same promise as those culled from embryos. Adult cells are fairly set in their ways, and don’t seem to grow or replicate themselves as quickly as [embryonic stem cells]” (Reaves 3). This creates a problem for scientists, since research using adult stem cells is far behind that of embryonic stem cells, scientists don’t want to spend years of research and experimenting just to get where they are with embryonic stem cells right now.
The final case against stem cell research is the fact that someday as a result of research people will use the technology just for personal gain. One example of this would be private cloning. If we find out how to manipulate cells to grow into what we want, people will offer services of cloning pets or even people just so they can get money. Genetic engineering will also be possible. If a family wanted to have children that possess certain attributes such as blue eyes or brown hair, they would be able to go to a private company and have their child’s cells be manipulated to produce the desired result. Some say that this will happen if society “carelessly [slides] down the slippery slope of destroying human life in order to advance our scientific curiosity” (Reaves 3).
III. Argument in Favor of Stem Cell Research
Even though there are some in society who believe stem cell research is morally unacceptable and should be banned, many people believe that stem cell research should be allowed. One of the primary arguments supporting stem cell research is that they have a really good probability for “dramatic cures for cancer, heart failure, Parkinson’s disease, muscular dystrophy, diabetes, kidney disease, multiple sclerosis and a host of other diseases” (Stem Cell Research 4). If scientists do figure out a cure for any of those listed, the interest in stem cells would grow exponentially and would get attention from all over the world. Then people would help raise money for research and the government could possibly legalize federal funding, but because federal funding is not legal in the US “new treatments will be delayed by years, and many who might otherwise have been saved will surely die or endure needless suffering” (Goldstein 2).
Anther reason why stem cell research should be legal is that it may be able to produce organs or replace bad cell tissue. If scientist can grow organs in a lab it will decrease the waiting time for organ transplants greatly. Today the many people waiting on an organ transplant list will either not get an organ or not get it in time. Stem cell research offers the “possibility of a renewable source of replacement cells and tissue” (Center for Bioethics 3). Doctors would be able to take cells, such as heart muscle cells, and transplant them to a heart “in order to augment the function of the failing heart” (Center for Bioethics 4). That process would save tens of thousands of people. This is what could cure diabetes for many people. Doctors would inject new pancreatic cells that would fix your pancreas and cure you of diabetes.
The final reason why stem cell research should be allowed is that it will help us more understand how the human body and cells work. If we knew how genes and cells make decisions on what to do we would be able to control them. That would possible if we could “[identify] the factors involved in the cellular decision-making process that results in cell specialization” (NIH 3). Because we know that diseases such as cancer are caused by abnormal cell division we could stop the cells from dividing if we knew how they communicate that message by changing the message outputted by the cancerous cells. This would allow us to cure all types of cancer and save millions of lives. Birth defects would also be able to be stopped as a result of this discovery.
IV. Conclusion
Even though some believe that doing stem cell research is morally wrong and should be completely banned, the truth is stem cell research is a vital asset in finding cures to the many illnesses and diseases people live with daily. Although embryonic stem cell research does destroy the embryo, it is done on embryos from abortions and from fertility clinics, which allows the embryos to be put to good use instead of wasting them by not using them. They also have the ability to grow into organs that can be used for organ transplants, saving many peoples lives by shortening the waiting period. Stem cells have the “potential to revolutionize the practice of medicine and improve the quality and length of life” (Center for Bioethics 6). Stem cells also will help us find out how the body’s cells work and further our knowledge on the human body, which could lead to new developments in drugs. Because of the disagreement between allowing stem cell research and not allowing it, Americans and all other people in the world are being denied possible cures. Eventually there will be cures found, but if stem cell research is not federally funded that process will take a lot longer. Sooner or later people will realize that stem cell research should be taken advantage of because of its potential. A president will most likely pass a bill allowing federal funding and then within a year or two a major breakthrough will be found.

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Different Sides of Embryonic Stem Cell Research

The field of stem cell research remains highly controversial because of its ethical and moral values. “Despite the news in 2006 that researchers had found a way to harvest human embryonic stem cells without having to destroy embryos, controversy still surrounds potentially life-saving stem cell research.” (Gruen, 2007). Due to the strong emotional responses to some of the subject matter by the pro-lifers and certain religions and politics in general, I will attempt to explain different sides of embryonic stem cell research (ESC). This study describes what viable embryos are and the issues connected with them. Are stem cells viable embryos? Can they ever be a human being? Stem cells are no more than a precursor for some type of cell. They are not tiny embryos nor can they ever become embryos. Are human embryonic stem cells embryos? Although stem cells of themselves are not embryos, they are pluripotent; they can develop into any cell or tissue of the body. They are not capable of forming a new individual, as a fertilized egg or single cell taken from a four-cell embryo might if cultured in vitro and placed in a uterus. Stem cell research has become a subject of political discussion in recent years because of its social and ethical implications, but what is the big controversy with stem cell research? Most diseases are caused by the death of healthy cells in a particular organ. Parkinson’s disease is caused by the death of brain cells that produce a chemical call dopamine and diabetes is caused by the death of insulin-producing cells in the pancreas. None of these organs can replace the cells that die. With stem cell therapy, these cells can be replaced. Researchers and scientists study stem cells to get a basic understanding of the process in cell development and disease. “The opposition of research on human embryos usually start and finish their argument with the claim that the human embryo is, from the moment of conception,a living, innocent human being. But the morality of using a being for research should depend on what the being is like, not on the species to which it belongs.” (Singer, 2001) This being of 64 cells has no brain and has never been conscious and can feel no pain. Take for instance researchers who do research on rats, the rats are not capable of preferring not to be in situations that are painful and frightening to them. There are two types of stem cells that are found in humans and animals: embryonic stem cells and adult stem cells. Embryonic stem cells have the potential to develop into any organ or type of tissue in the body. This property is called pluripotency. According to the MSN Encarta, “Embryonic stem cells exist in fully developing embryos for a limited period of time (about three weeks). However, embryonic stem cells produced in laboratory conditions continue to divide and can be sustained almost indefinitely in nutrient cultures.” (MSN Encarta, 2000) Since these stem cells can divide and copy themselves indefinitely, it is not necessary for researchers to take continually stem cells from human embryos because they can maintain a stock of them. They call this stock a cell line, which is similar to our family lineage. Below is a picture of pluripotent stem cells. {draw:frame} (www.csa.com/discoveryguides/stemcell/overview.php) Researchers and scientists use two major venues in researching diseases in regenerative medicine: differentiating stem cells into certain types of replacement tissues and using the stem cells to observe how diseases develop in them, which also leads to the development of effective drug treatments (Mitchell, 2008). During those eight years, I believe many Americans have changed their minds about stem cell research because they do not want to see their family or friends, or even themselves, suffer from Alzheimer’s, Parkinson’s, or any other disease that has a chance of being reversed or cured. When President Ronald Reagan died from Alzheimer’s disease, Nancy Reagan then hoped that one day there may be a cure for Alzheimer’s disease. Again with the death of the actor Christopher Reeve’s, who was paralyzed by spinal cord injuries and was a vocal campaigner for stem cell research, the hope for stem cell therapy was highlighted. With a new President in the House, these issues may be changed because President Obama has long favored stem cell research. In 2007, he said, “I am frustrated…that we are preventing the advancement of important science that could potentially impact millions of suffering Americans…” Furthermore, this brings up the controversial issue whether it is morally right or not. Some people might argue that this is not morally right. The Catholic Church believes that nothing should be done to an unborn fetus. “There seems to be no middle ground for the Catholic Church when it comes to the sanctity of life for the unborn.” (Ruse & Pynes, 2006). So just how much influence should religion have on any aspect of what the government does with respect to stem cell research? Are human embryonic stem cells embryos? Should religion have reign over whether someone is willing to give up her aborted fetus for science or should it be the right of the person? The Fourteenth Amendment gives us the right of privacy and the right for a mother to abort a fetus. Because of the pro-lifers beliefs, should adult stem cells be used instead of embryonic stem cells? Are they more beneficial than embryonic stem cells? Adult stems cells greatest advantage is that it can usually use a person’s own stem cells. Adult stem cells disadvantages are that these cells cannot multiply indefinitely. Adult stem cells in animals have been proven to be extremely impressive. Adult stem cells given to a person with Parkinson’s had results that were very similar to embryonic stem cells, where a patient had almost a full recovery for several years after the transplant. Embryonic stems cells have advantages too. They have exceptional promise for the finding of cures for many diseases. They have the potential to form every cell type and have rapid proliferation. Embryonic stems cells have a lack of rejection and an extremely important usefulness in drug testing and disease models. These embryonic stem cells make up a larger proportion of a developing embryo than do adult stem cells. {draw:frame} Accordingly, with stem cell research funded by private companies or the government, research should not be stopped. The benefits of stem cell research outweigh the cost in terms of embryonic life because this means that they have the capacity to be used for cellular therapies to treat a wide range of diseases. The embryonic stem cells potential to treat diseases is much greater than the costs associated with the destruction of embryos. “As controversy, objections, doubt, and debate still surround stem cell treatment in the United States , many U.S. patients have opted to make the trip to China where stem cell treatment for spinal cord injuries, multiple sclerosis, cerebral palsy, and ataxia are being practiced in more than 100 Chinese hospitals.” (2007) Adult stem cells cannot reproduce themselves indefinitely. They do not divide fast enough to offer immediate treatment. If there is DNA abnormalities in the adult stem cells that will make them unusable for treatment. Nevertheless, the value of life is a fine line where the embryo becomes a human being. Embryos first heart beat is not usually until their fifth week in the womb. Embryonic stem cells are only used up until the third week of a pregnancy and brain activity does not begin developing until the 54th day after conception. The embryo does not attach to the uterus until 14 days after fertilization. These embryos are a cluster of cells or blastocysts for the first three weeks after conception. They have no differentiation into any distinct organ tissue and the viability of a fetus living outside the mother’s womb has been set at 22 weeks due to artificial aid. There was a recent article on January 23, 2009 from the Geron Corporation press release that Geron Corporation has been given FDA clearance to begin the world’s first human clinical trial of embryonic stem cell-based therapy. This trial will be used on patients with “complete” American Spinal Injury Association (ASIA) grade A subacute thoracic spinal cord injuries. To be able to help people who are quadriplegics by injecting stem cells into their body to cure them, would be the greatest gift of all. There is no telling how far stem cell research can go. Every day there is something new on this subject, what will be next?

Albrecht, S. M. (2001). Forging new directions in science and environmental politics and Policy: How can co-operation, deliberation and decision be brought together? Gruen, L. (2007). Stem cell research: the ethical issues. Blackwell Publishing Retrieved: February 4, 2009, from Axia College, Apollo Library. Gale Document Number: A179652146

Mitchell, H. (2008). The growth of stem cell research. The Cornellian, January, 2008. Retrieved February 4, 2009, from www.thecornellian.com. Patients seeking stem cell research overseas. Physician’s Money Digest (July 2007): 18(1) Academic One File. Gale. Apollo Library. 4 Feb. 2009. Reprogramming the debate: Stem-cell finding alters ethical controversy. (2007). Space Daily (Nov 21, 2007): NA. General One File. Gale. Apopllo Library. 4 Feb. 2009. Gale document number: A171618409. Ruse, M. & Pynes, C.A. (2003). The stem cell controversy: Debating the issues_._ Amherst, NY: Prometheus Books. Schull, D. (2009, January 23). Geron receives FDA clearance to begin world’s first human clinical trial of embryonic stem cell-based therapy. Retrieved from http://www.geron.com/media/pressview. Singer, P. (2001). Using human embryos is morally acceptable. San Diego: Greenhaven Press. Retrieved February 4, 2009, from Axia College, Apollo Library, Opposing Viewpoints Resource Center. The Stem Cell Controversy. (2006). Debating the issues. New York: Prometheus Books. Viegas, J. (2003). Stem cell research. New York: The Rosen Publishing Group, Inc. Roe vs. Wade. (2009) Retrieved March 6, 2009, from http://www.thepetitioncite.com Peer Review Checklist*

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6 CRITICAL ISSUES11 ADVANCED ISSUESSCORE: 92

Characteristics, Sources and Function of the Mesen

MSC are initially recognized in the late 1960s by Friendenstein and colleagues, as an adherent, non-phagocytic, fibroblast-like population that could regenerate rudiments of normal bone in vitro and in vivo (Friedenstein et al. 1970; Friedenstein et al. 1974a; Friedenstein et al. 1974b). The group identified a homogenous spindle-shaped adherent cell population when they cultured whole bone marrow (BM) in vitro. Then, this assay was developed into colony forming unit-fibroblast (CFU-F) assay which is the standard method to identify MSC. Later, Pittenger et al showed that MSC differentiate into lineages of mesenchymal tissue, including bone, cartilage, fat, tendon, muscle, and marrow stromal (Pittenger et al. 1999). This multilineage differentiation ability has been further exploited in tissue engineering. MSC attract much interest of scientists when their immunomodulatory functions were described (Bartholomew et al. 2002; Di Nicola et al. 2002; Tse et al. 2003).

2.2.1 Sources of MSC

MSC can be isolated from various sources and wide range of species. Among, the most extensively defined and investigated sources are human (Pittenger et al. 1999) and murine MSC (Nadri and Soleimani 2007; Anjos-Afonso and Bonnet 2008). In addition, MSC also have been derived from various animal including non-human primates (Ke et al. 2009), dogs (Neupane et al. 2008), pigs (Bosch et al. 2006), cows (Bosnakovski et al. 2005), chicken (Khatri et al. 2009) and horses (Arnhold et al. 2007). This provides a large animal model to test MSC therapeutic potential in both human and veterinary medicine. In humans, MSC have been identified and described in variety of tissues. Among, adult bone marrow (BM) is the most common source of MSC and extensively studied. The frequency of MSC in BM is low and estimated to constitute about 0.01-0.001% of the nucleated cells. This instigates the efforts to explore the alternative sources of MSC. In line with, MSC have been isolated from foetal tissues (Campagnoli et al. 2001) and other adult tissues including granulocyte colony stimulating factor (G-CSF) mobilized peripheral blood stem cells (Kassis et al. 2006), adipose tissue (Locke et al. 2009), appendices (De Coppi et al. 2006), scalp tissue (Shih et al. 2005), cardiac tissue (Tateishi et al. 2007) and placenta (Barlow et al. 2008). Besides, MSC also have been isolated from umbilical cord blood (Lee et al. 2004b) and normal adult peripheral blood despite the low yield (Zvaifler et al. 2000). Surprisingly, MSC also present in human endometrium and menstrual blood recently (Hida et al. 2008; Gargett et al. 2009). The findings confirm MSC stromal support and mobilisation properties. Of all the sources, the frequency of MSC is higher in the tissues of the early life/newly formed (foetal tissues, cord blood, placenta) than adult tissues suggesting that they may play an important role in early tissue formation.
2.2.2 Isolation of MSC

In general, MSC can be isolated by standard cell culture method by exploiting the plastic adherence property of MSC. Though, it is not sufficient to achieve high purity as the adherent cells fraction may contain other cell types. Various approaches have been tested to enrich MSC population in vitro. Several groups employed positive selection in isolation of MSC using monoclonal antibodies labelling such as Stro-1 (Simmons and Torok-Storb 1991), CD133 (Tondreau et al. 2005), CD271(Poloni et al. 2009) and CD105 (Roura et al. 2006). On the other hand, instead of positive selection, MSC can be purified by depleting other cells in the samples (Lee et al. 2004b; Tondreau et al. 2005). Besides, modification of culture media formulation including serum pre-selection, conditioned media, and addition of growth supplement may also selectively promote MSC growth in culture.

2.2.3 In vitro Characteristic of MSC

MSC colonies can be isolated by plastic adherence after collection/extraction of nucleated cells from the primary source. At early phase of culture, the colonies are usually heterogeneous given the fact that other cell types presence in the sample. Over the time, about 2-3 passage, non-MSC will be washed away, leaving exclusively adherent, fibroblast-like cells due to the high rate of clonally expansion of MSC. Although purity of MSC is definite at later passage of culture, these single-cell-derived colonies are morphologically heterogeneous (Mets and Verdonk 1981; Colter et al. 2000). Collectively, the studies identified two different MSC with inimitable appearance and unique properties. These subpopulations are: (1). small, spindl-shaped and rapidly renewing cell; (2). larger flatter slow-growing cell.

Due to their self-renewal ability, MSC can be maintained for 50-100 passages. Nevertheless, this is depending on the origin of the species (Bianchi et al. 2003; Meirelles Lda and Nardi 2003; Yanada et al. 2006). Throughout the cultivation, in vitro senescence of MSC is noticeble. Senescent MSC reduce their proliferation ability; show accumulation of cells with large and mature character as well as decline in multipotentiality of differentiation (D’Ippolito et al. 1999). Telomere shortening in human cells can induce replicative senescence which blocks the cell division. The mechanism is controlled by activity of telomerase which is highly expressed in tumour cells and embryonic stem cells. Telomerase enables indefinite proliferation of these cells. However, most somatic cells lack of telomerase activity or have a low level of this enzyme. Several studies showed there is no or low telomerase activity in MSC using highly sensitive assay (Banfi et al. 2002; Yanada et al. 2006). This denoted that MSC senescence is associated with shortening of telomere length. In addition, the origin of MSC also play role in determining their senescence rate. MSC from old donor may encounter difficulties in initial cultivation and accelerated senescence in vitro (Stenderup et al. 2003; Shamsul et al. 2004).

The Heated Debate Concerning Stem Cell Research

Inside an embryo there are dozens of stem cells. They are basically empty shells, but the special thing about them is that they are pluripotent, meaning that they can develop in to any cell or organ in human body. That makes stem cell research a gigantic part of today’s medical research. With enough research, stem cells can be a big help to the human kind. Their extraordinary abilities could help scientists return memory to Alzheimer’s patients, or grow a man’s limb that had to be amputated due to some tragedy. But, they also have some flaws. As the name suggests, Embryonic stem cells can only be found in embryos and acquiring them destroys the embryo. Embryos are considered by many people to be alive; this creates a rather difficult question. Is it alright to take one life in order to save the other?
Stem Cell research can give the answer to many of the complicated events that come about during human development. According to the National Institutes of Health, “A primary goal of this work is to identify how undifferentiated stem cells become differentiated.” And since some of today’s worst medical condition, for example cancer, are the result of defective cell differentiation, this research could help better determine the cause of it and perhaps suggest a better cure. Another use of embryonic stem cells includes testing new drugs. Although stem cells are already in use for drug testing, they can only be used on specific differentiated cells that have the same properties as the disease of the drug they are being tested for. Due to embryonic stem cells’ pluripotent property, they can be used for any disease imaginable. But perhaps the most significant use of these stem cells is generation of cells or tissues to be used for cell-based therapy. For example, replacement of the cells or tissues can give scientists the ability to treat diseases like Parkinson’s disease, strokes, heart disease, and wide variety of other diseases.
Even though embryonic stem cells can be a great use to human kind, the fact is that this help comes at a terrible price. Embryonic stem cells can only be found in blastocyst of an embryo. There are those who believe that life begins at conception, so the blastocyst is a human life and to destroy it is unacceptable. Stem Cells can also be found in the umbilical cord of a baby just born. According to DO NO HARM, the coalition of Americans for research ethics, these stem cells are currently the only ones being used to treat humans, and have had positive results. Thanks to these cells, a number of drugs have been successfully tested and are now available. If less money is spent on the research of embryonic stem cells, the adult stem cell research could provide even greater advances. Another reason for abandoning this research is that all the promises made by scientists have not been proven. According to the Institute for Creation Research, they are all theories at best.
Embryonic stem cell research could be a great help to society, but it can also take it on a downward spiral. This research can give answers to questions that have been asked since the beginning of time. With it humans can, in a sense, be made better, not have to deal with Alzheimer’s or Parkinson’s disease, and would make a lot of lives better. But in order to cure these diseases, we have to take the lives of those not even born yet. These cells could also make testing drugs better, but instead of using these cells if more research is done into other stem cells they could be more useful.
The research on embryonic stem cells has been a controversial topic ever since it was first suggested. Recently, U.S. President Barack Obama issued an executive order removing barriers to scientific research involving human stem cells. But still there are those who are opposed to the president’s decision.

Works Cited
The National Institutes of Health. “Stem Cell Basics what are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?” Stem Cell Information. 20 Feb. 2008. Resource for stem cell research 20 Mar. 2009
.
Watson, Stephanie. “How Stem Cells Work.” How Stuff Works. 11 Nov. 2004. How Stuff Works. 21 Mar. 2009
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DO NO HARM. “Stem Cell Report.” 2002. The Coalition of Americans for Research Ethics. 22
Mar. 2009.
< stemcellresearch.org/stemcellreport/scr-2002-fall.htm>.
“What are embryonic cells and why are they important?” The Guardian. 9 Mar. 2009. 11 Aug. w 2009 .
W < http://www.guardian.co.uk/science/2009/mar/09/embryonic-stem-cells>.

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Stem Cell Therapy

In order to discover the ways for the remedy of diseases, studies in therapeutic approaches have been doing widely and kept increasing at accelerated pace. A lot of research areas had emerged for that purpose including one of the most fascinating and highly active areas at present, stem cells therapies. Due to self-renewal property and differentiation capability of stem cell, it becomes a new hope in modern treatment.
The first successful case of stem cell therapy in human was reported in 1959. Bone marrow restorations were observed in leukemia patients who received total body irradiation subsequent by intravenous injection of their twins’ bone marrow (Thomas et al, 1957). Nevertheless, that effect was transient and the following bone marrow transplantation attempts in non-twin patients and donors can eventually lead to patient’s death from graft-versus-host disease (Mathé et al, 1965). During that time, the safety of hematopoietic cells transplantation was not guaranteed because of the limited knowledge in human histocompatibility and immunosuppression. However, the turning point came after the discovery of human leucocyte antigen (HLA) groups (Dausset, 1958; van Rood et al, 1958), HLA typing and compatibility testing were performed prior to the transplantation. In addition, the improvement of immunosuppressive protocol also helps bringing the bone marrow transplantation to become more and more successful (Donnall and Hutchinson, 1999).
Although the success rate of hematopoietic stem cell therapy was great, patients’ mortality still happened as a result of some factors. Besides from graft-versus-host disease which have previously mentioned, infection contributes for most cases of patient death (Kernan et al, 1993). In allogeneic transplantation, patient’s immunity needs to be suppressed to avoid graft rejection. During such immunoincompetence period, there is a high risk that patient might get infected either from viral reactivation, hepatitis B (Hammond et al, 2009) and herpes simplex virus (Pillay et al, 1992) for instance, or other opportunistic infections such as Candida species (Wingard et al, 1991) and cytomegalovirus (Leung et al, 1999). However, this problem could be minimized in nonmalignant patients by using autologous transplantation.
Cell contamination is another risk factor in stem cell therapies that should be concerned. Since stem cells are human-derived products, contamination could occur at any steps in process. Start from stem cell sources or donors, they might carry viruses, parasites or diseases that can infect patients after transplantation. So, donor screening tests and assessment need to be performed (Sacchi et al, 2008). Medical and familial histories of donors are also essential and should be scrutinized in order to avoid getting stem cells from someone that might transmit congenital defect, autoimmunity or malignant disease to the patient (Niederwieser et al, 2004). Harvesting and culturing of stem cells are the processes that might have caused the microbial contamination as well, thus, sterile technique must be cautiously conducted during those steps.
Up till now, bone marrow or hematopoietic stem cells transplantation has been proofed to cure many diseases such as aplastic anemia, acute and chronic leukemia, and severe thalassemia with low complications in patients (Thomas et al, 1975; Lucarelli et al, 1984). As a result from the prosperous in hematopoietic stem cell transplantation, researchers and physicians are trying to extend this aspect to other diseases and different types of stem cell. Mesenchymal stem cell and embryonic stem cell are two of those that have been broadly used in studies of stem cell therapies. Immense potential in in vitro and animal treatments of stem cells were observed in many diseases including breast cancer (Li et al, 2010), muscular dystrophy (Sampaolesi et al, 2003), acute renal failure (Morigi et al, 2004) and diabetes mellitus type 1 (Kofman et al, 2004) as reported in previous literatures. When it comes to clinical trials in human, however, the controversial exist. Stem cell did not show impressive effects as they did in bone marrow transplantation or preclinical models. Furthermore, some cases that showed dangerous complication of stem cell therapy were reported recently. A teenage boy who repeatedly received fetal neural stem cell injection for ataxia telangiectasia therapy, four years later, had found to develop nonself-origin brain tumor derived from more than one donor transplanted stem cells (Amariglio et al, 2009). This case provides the first solid evidence to proof that transplanted stem cells could give rise to malignant transformation. Another interesting case was reported in lupus nephritis patient who undergone autologous hematopoietic stem cell transplantation by direct renal injection. Angiomyeloproliferative lesions which believed to be derived or induced by stem cells were developed at the injection sites, moreover, hemodialysis and hematuria were noticed. Patient’s symptoms gradually deteriorated and finally died of sepsis after 2 years have passed (Thirabanjasak et al, 2010). These cases raise even more questions in stem cell therapy.
Although there are some risk factors in using stem cell for therapeutic approaches, hematopoietic stem cell therapy by bone marrow transplantation has already been proofed to be safe if donors’ background and screening, cell contamination, HLA matching and opportunistic or nosocomial infections during immunocompromised period were carefully monitored and controlled. Still, other types of stem cell therapies, despite of their good therapeutic efficacy, are remain in experimental stage and need more data to support and demonstrate the safety in clinical trials. More understanding of stem cell biology is also required in order to keep stem cell under controlled and avoid some complications that they might cause. So, to pave the way for successful stem cell therapy, research in this extent is needed to pursue to maximized therapeutic efficiency with highest safety in patients.

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Embryonic Stem Cell Research Provides Revolutionary and Life-saving Breakthroughs

“Stem cell research is the key to developing cures for degenerative conditions like Parkinson’s and motor neuron disease from which I and many others suffer. The fact that the cells may come from embryos is not an objection, because the embryos are going to die anyway.”
— Stephen Hawking
The phrase “stem cell” calls to mind images of controversy: Pro-life picketers outside abortion and in-vitro fertilization clinics, patients with chronic disabilities waiting on a cure, scientists in a lab experimenting with a petri dish. These cells offer unimaginable opportunities for regenerative medicine because they can retain the ability to differentiate. Stem cells are classified as either adult or embryonic. Embryonic stem cells can reproduce any cell in the body, whereas adult stem cells can only produce somatic cells within their own tissue type. Somatic simply means a cell that is not directly involved in sexual reproduction. What makes research into stem cells exciting is that they can provide a means to regenerate cells in a way that humans cannot accomplish on their own. Spinal cord tissue can be regenerated in paraplegics, giving a new lease on life to war veterans. Mental diseases associated with age such as dementia, Alzheimer’s, and Parkinson’s, can be cured. Even entire organs can be reconstructed and implanted into patients that desperately need them, such as in the case of Claudia Castillo, who received a bronchus coated with her own cells.

Why then is such a cutting-edge and promising field subject to so much controversy? Because one of the primary sources for stem cells is blastocysts, undeveloped microscopic human offspring only 200 cells large. Generally the opponents of stem cell research are also pro-life, or opponents of abortion, as the process for isolating stem cells from blastocysts often destroys the blastocyst and any potential for life. In order for stem cell research to be considered morally justified by an individual, one would have to consider blastocysts to be cells that are ‘living and human’, rather than being a ‘living human’, or at least weigh the positive good that treatments derived from stem cells can provide against the negative drawbacks of destroying a potential life.

Studying cadavers was as equally a distasteful process in its own time, as stem cell research is to some people today. “[Dissection] was so reviled by the public that even in the nineteenth century, there was a near state of hysteria to prevent it.” However, most people today recognize that without it we would only have rudimentary knowledge of human anatomy, and a plethora of treatments and procedures would never have been discovered. Regardless, until 1719 the practice was heavily regulated in Great Britain, and “any physicians known to perform human dissections were excommunicated by the Church.”2 “Stem cell research…today is in many ways analogous to the treatment of dissections.” Stem cell research will contribute to modern medicine in ways we can only imagine, but it needs federal funding and guidelines to get there as soon as possible. Many Americans who have fallen victim to Multiple Sclerosis or Lou Gehrig’s Disease no longer have the luxury of time, a commodity currently being wasted by political posturing to satiate a vocal and misleading minority.
Stem cells have been in use since the first successful bone marrow transplant over 40 years ago. Human bone marrow contains adult stem cells, specifically hematopoietic, or blood-generating, stem cells. The controversial flavor is embryonic stem cells, which have captivated imaginations and headlines since James Thomson first developed a method to obtain them in November 1998. Beginning with the Supreme Court decision in Roe v. Wade, fears of human cloning and the creation of chimeras, animal-human hybrids, as well as protests from Pro-life groups, pressured politicians to enact stringent restrictions on the procedures of stem cell labs that receive government aid.

The Department of Health and Human Services maintained a moratorium on federal funding for research on embryos and fetuses, as well as in vitro fertilization, until President Clinton issued an executive order lifting it in 1993. However, Congress banned federal funding for human embryo research by adding legislation known as the Dickey-Wicker Amendment to every appropriations bill for the National Institutes of Health since 1995, making it impossible for the President to overturn the ban without also cutting the cash flow to the NIH. This restriction remains in place today. On August 9, 2001, President Bush “clarifies which human embryonic stem cells can be used under federal funding rules” by stating that any lines derived from excess IVF blastocysts before his announcement are eligible for grants. Then in 2009, President Obama lifted the ‘made-before’ restriction for stem cell lines but maintained the ban on creation and destruction of embryos for research purposes.

With all these restrictions and complications, many scientists started to consider moving their research to countries with more liberal stem cell policies, such as Australia, Japan, and the United Kingdom. To combat this potential brain drain and create jobs within their own borders, states began to enact laws promoting stem cell research. Most notable is California, who in 2004 pledged to spend $3 billion on stem cell research, and gave it constitutional protection. Still, states vary on what practices they allow, and the lack of universal standards makes collaboration difficult. And a great deal of appropriations go to duplicating lab technology so as to make sure not to upset the confusing regulatory laws. If the federal government funded all forms of stem cell research, it could implement policies that were consistent across state lines, thereby promoting collaboration and eliminating waste from having twice the necessary amount of lab infrastructure.

Terms such as adult and embryonic may not mean much to lay people in terms of stem cells. As you may have guessed, adult stem cells are found in adults. But, they are also found in the umbilical cord. What makes adult stem cells different from their embryonic counterparts is that they may only create cells within their own tissue group, whereas embryonic stem cells are pluripotent, meaning they can “generate any kind of cell in the adult body”. Embryonic stem cells come from the inner cell of a blastocyst, which is the last stage of a zygote in in-vitro fertilization before it is implanted in a woman’s uterus and becomes a fetus. It is these cells that are controversial because most lab practices destroy the blastocyst to isolate the stem cells. Fortunately, a Massachusetts biotech company was able to remove one cell from an 8-cell embryo without destroying it as part of a process called pre-implantation genetic diagnosis(PGD). In this process, the removed cell is tested for genetic diseases that it may have inherited from the parents. The same process could be used to culture embryonic stem cells and allow the embryo to “grow into a normal baby” at the same time.

One common misconception is that stem cells only come from aborted fetuses, and that as a result women will be more likely to choose an abortion if she knows it will contribute to scientific research. In reality, only fetal germ cells, a certain type of stem cell found in four- to six-week-old fetuses, are developed from fetal tissue, and most groups against embryonic stem cell research do not protest this type of research. These germ cells do not even possess much therapeutic potential in the eyes of many researchers. Most embryonic stem cells come from frozen blastocysts left over from IVF procedures. In-vitro fertilization entails the production of 8-10 blastocysts so that they can be tested for viability and give the prospective parents the best chance possible at conception. Not all blastocysts are used of course, and these surplus frozen blastocysts would otherwise be discarded as biomedical waste.
Another myth is that stem cell research will inevitably lead to human cloning. The truth is that most people in the scientific community agree that human cloning is not only impossible with current technology, but that even if it were possible it would be unfavorable and immoral. Most animal clones have very short life spans and many health defects, so even if a human clone was somehow produced, the mistake would in all likelihood be short-lived.

Even though embryonic stem cell research is in its infancy, most scientists agree that it is a highly promising field for the treatment and curing of many chronic degenerative illnesses. Amyotropic lateral sclerosis(ALS), also known as Lou Gehrig’s Disease, destroys motor neurons which are responsible for muscle movement. Stem cells could be used to replace these neurons, as well as damaged nervous tissue present in Alzheimer’s, Huntington’s, and Parkinson’s. Even if the stem cells themselves are not used in treatments until much later in the future, they can be used to grow diseased tissue for study and for testing potential drugs on.

Stem cells also have the potential to cure Type 1 Diabetes. In this disease the immune system attacks and destroys the body’s own pancreatic beta cells, crippling the patient’s ability to produce insulin. Stem cells can be used to repair the damage by replacing the lost beta cells, and the patient can take immune-suppressing drugs to prevent new damage.
Adult stem cells have been used for over 40 years in bone marrow transplants to treat leukemia. In this procedure, the patient is subjected to radiation to destroy his existing immune system, and is then injected with bone marrow from a compatible donor to replace it. This works because bone marrow contains hematopoietic stem cells, which can produce over 20 types of red and white blood cells.

Another potential utilization of embryonic stem cells is the creation of replacement limbs and organs that cannot be rejected by the body. In 2008, a Colombian woman received a new bronchus grown from her own stem cells. The process took a cadaver’s bronchus, a branch of the trachea, and stripped it of its cells with enzymes and detergent. The resulting ‘scaffold’ was then coated with the patient’s stem cells from her bone marrow and left to grow in a ‘bio-reactor’. Once it was complete, it was cut to fit the tuberculosis-damaged tissue of the patient and transplanted. “Just four days after transplantation, the graft was almost indistinguishable from adjacent, normal bronchi”, says Prof. Macchiarini. The best part about this breakthrough: the patient, Claudia Castillo, has exhibited “no sign of her immune system rejecting the transplanted organ”14, which is usually a problem for transplant patients and requires them to take immune-suppressing drugs for the rest of their lives. Doctors are optimistic that this type of procedure can be expanded to all sorts of organs, and that it will revolutionize transplantations.

Despite all these exciting potential leaps in health technology, many oppose embryonic stem cell research on moral and religious grounds. Generally, pro-lifers, or people opposed to abortion, also tend to oppose experimenting with embryonic stem cells. One reason is the perception that allowing such experiments would legitimize abortion as an appropriate decision, since the abortion would provide a resource for the experiments and thereby contribute to human knowledge. But in reality only the first stem cells came from fetal tissue and most, if not all, embryonic stem cells come from leftover IVF blastocysts, not aborted fetuses. And in the last 30 years, no evidence has been found that a woman’s choice to abort was influenced by its ability to contribute to stem cell research.

Another reason that the right-to-life crowd is against embryonic stem cell research is because they believe that life begins with the zygote, and that destroying it any point after that stage constitutes murder. In the Vatican’s official statement, they state that person-hood begins at conception when the zygote is infused with a soul, and as a result, said zygote is entitled to the protection of the law. Many Christian Americans of various denominations share this conviction. Some call for methods to extract stem cells without destroying the blastocyst, like in pre-implantation genetic diagnosis. Others, including former President George W. Bush, argue that rather than use the surplus IVF blastocysts for research, they should be frozen indefinitely until they are ‘adopted’ by other infertile couples. This option has been available for years, but since 1980, only a hundred or so ‘snowflake babies’ have been born. These results make sense: after all, “those who are not able to become genetic parents can adopt live children without going through the risk and trouble of pregnancy”. This very low rate means that embryo adoption is not a viable solution to the growing amount of frozen embryos. Even if it were, the federal government has no jurisdiction over the “dispensation of embryos”. That is still the prerogative of the genetic parents. Finally, some call for the end of current IVF practices responsible for the surplus. This is unreasonable, however, as each cycle of in-vitro fertilization costs about $10,000. Infertile mothers want this money to lead to a successful pregnancy, and as only 30% of embryos actually implant to the uterine wall, the creation, storage, and use of multiple embryos is necessary, especially if the first attempt fails. Over 400,000 frozen blastocysts exist in IVF clinics throughout the Unites States of America, of which many will have to be discarded as biological waste. For James Thomson, who grew the first embryonic stem cells, “'[the morality of stem cell research is] a very complex issue, but to me it boils down to [using embryos to help people rather than throwing them out]’”. On a side note, Christianity is the only major religion in the United States to formally express concern and distaste for stem cell research.

The last popular argument against working with embryonic stem cells is that it may lead to human cloning, and possibly the creation of fully developed, half-man, half-animal creatures known as cybrids and chimeras. Clones have terrified people since their debut on Hollywood, but in actuality, creating human clone armies is impossible with current technologies, and the animal clones that have been successfully created tend to age rapidly or have crippling birth defects. Still, cloning has had a significant impact on our culture, evidenced by the science-fiction book The House of the Scorpion. In this book, Mateo, the 10-year-old clone of a wealthy drug lord, is first treated like the son of a cleaning woman, until he discovers a stamp on his foot that reads ‘property of El Patron’. When his quest to discover its meaning results in his first contact with the outside world, he is locked away from view and treated “like a dog.” Then El Patron, the opiate kingpin, comes to his aid and treats him like a son until El Patron suffers from a heart attack. At this point in the story, Mateo discovers that he is the latest in a line of clones that were created and raised for the singular purpose of harvesting replacement organs for El Patron. It is this fate that right-to-life groups claim is the future of the United States if therapeutic cloning is sanctioned by law. Mainstream scientists agree that making human clones is undesirable because of the potential harm to both the clone and the mother, and that it will remain the stuff of fiction for the foreseeable future. However, therapeutic cloning holds a great deal of legitimate promise for suffering patients. In this procedure, a somatic, or adult, stem cell is taken from the patient and placed inside an egg cell that has its genetic material removed. This is called Somatic Cell Nuclear Transfer(SCNT). It is the same process that led to the creation of Dolly the cloned sheep. The resulting zygote is activated by electricity and chemicals, and in theory should divide until it becomes a microscopic blastocyst, which can be harvested to obtain embryonic stem cells genetically identical to the patient. This process is completely removed from the concept presented in The House of the Scorpion, as the embryo is harvested before it has developed a consciousness, the capacity to feel pain or love, or developed any organs whatsoever. However, currently every attempt has failed before the zygote grew enough to provide stem cell lines.

Cybrids and chimeras, on the other hand, have been created for research purposes for about 40 years. A cybrid, in technical terms, is a cell “whose nucleus is from one source and whose cytoplasm is from another source.” They have been used to gain knowledge on cell division control and the locations and duties of certain human genes. In the future they may even be used to create blastocysts for research. Human female eggs are painful and dangerous to harvest, so scientists may begin to use rabbit or cow eggs to house human genetic material. There is no need to worry, though, as the eggs are stripped of nearly all genetic material and therefore cannot create minotaurs nor bunny-people. Chimeras are organisms whose bodies house cells with different sets of DNA. They get their name from the creature in Greek mythology, “a fire-breathing lion whose tail was a serpent and who had a goat’s head protruding from its back”. In research, mice are injected with human cancer cells to study cancer and test possible treatments. The presence of the human cells makes them technically chimeras, but they do not possess any human characteristics. Similarly, chimeras are utilized to study diseases like Parkinson’s and Lou Gehrig’s disease. Still, for some people, the combination of human and animal genetic material in these ways is unnatural and unethical, even if it does not yield a fully developed mythical creature.

Across the aisle from conservatives, many people believe that the current restrictions on embryonic stem cell research are hampering scientific efforts and delaying potentially life-changing discoveries. There are currently over 100 million people with chronic disabilities living in America; many of them could be saved by stem cell cures. Multiple sclerosis, cancer, spinal cord injuries, strokes, heart disease, and retinal degeneration, as well as diabetes and the neurodegenerative diseases previously discussed, could all be treated or better understood through embryonic stem cell research. Even if a blastocyst has a soul, opponents of stem cell research must also realize the hope that it represents for the sufferers of these terrible diseases. In the words of Barack Obama, “Those who speak out against stem cell research may be rooted in an admirable conviction about the sacredness of life, but so are the parents of a child with juvenile diabetes who are convinced that their son’s or daughter’s hardships can be relieved”.

If the ability to help those in need wasn’t enough, the more pragmatic concern of maintaining American supremacy in science and technology should be. Without federal funding and the resulting national policies and standards, the United States could well fall behind nations like Japan and the United Kingdom, where policies are more liberal towards embryonic stem cell research. The current lack of nationwide standards makes collaboration all but impossible, and leads to a waste of monetary resources. Intellectual resources are also at risk; scientists may feel that their research would be better off if they took it to a different country where at the very least there would not be restrictive and confusing guidelines. Without governmental intervention, discoveries of breakthrough procedures could be unnecessarily delayed by months or even years.
One secondary, but no less important, result of federal funding is the creation of jobs in the biomedical field. With unemployment rates on the rise due to the recession, states have begun to compete with each other for the potential bonanza that stem cell miracle cures represent. However, because of the conservative opposition to stem cell research, politicians from traditionally red states are stuck in a thorny “jobs-vs.-values dilemma”. In the meantime, blue states are widening the technological gap, with California owning “29% of U.S. biotech companies, including powerhouses Amgen and Genentech”. Regardless of politics, one thing is certain: Federal funding into embryonic stem cells will infallibly create jobs, something our economy needs desperately.

But all these benefits mean nothing if it means we are ideologically aligned with the Nazis, killing and torturing innocents in cruel experiments. In the 1980s, to develop some kind of benchmark for person-hood and avoid legalizing murder, Great Britain’s Warnock Commission decided that the development of the primitive streak makes an embryo an individual. The primitive streak is a thickening line that eventually becomes the central nervous system, signifying that the embryo can no longer divide into twins, thereby making it the beginnings of a person and no longer a collection of cells. This timeline is decidedly pro-research because most blastocysts are harvested for stem cells in 3-5 days, and the primitive streak takes 14 days to develop. Even the scientific community is divided on whether or not to recognize this cut-off point, but many countries make use of it in distinguishing between a ‘living human’ and cells that are ‘living and human’.

In conclusion, embryonic stem cell research has the potential to better the lives of millions of people, and the process can become streamlined if the federal government passes legislation allowing it to continue unfettered. With national funding comes policies and procedures that will be common across all states, enabling nationwide collaboration and eliminating the waste of appropriations due to the duplication of technological infrastructure. In addition, the removal of a ‘paperwork web’ will encourage scientists to stay in the country, and allow the private sector to feel safe about investing in the biotech industry. However, such legislation will be impossible to pass as long as an ill-informed conservative minority continues to protest against stem cell research on religious and flimsy scientific grounds. Of course, part of the blame lies with the mass media for incorrectly reporting on various practices in the field and causing many of the common misconceptions. But, if these obstacles can be overcome, revolutionary and life-saving breakthroughs can be discovered that much sooner.

Works Cited

“Advance stem-cell research.” Editorial. Wisconsin State Journal. madison.com, 11 Jan. 2009. Web. 3 Oct. 2014.
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Farmer, Nancy. The House of the Scorpion. New York: Scholastic, Inc, 2002. Print.

Gallagher, Kathleen. “Wisconsin stem cell patents to get review: No claim to fame.” Milwaukee Wisconsin Journal Sentinel. Journal Sentinel, Inc., 4 Oct. 2006. Web. 3 Oct. 2014.
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Goldstein, Lawrence S.B., PhD and Meg Schneider. Stem Cells for Dummies. Hoboken: Wiley Publishing, Inc., 2010. Print.

Herold, Eve. Stem Cell Wars. New York: Palgrave Macmillan, 2006. Print.

Hopkins, Jim. “Stem cells’ promise pits jobs vs. values.” USA Today n.d.:MAS Ultra – School Edition. EBSCO. Web. 4 Aug. 2014.
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Obama, Barack. “Finding a Middle Ground.” Vital Speeches of the Day 75.7 (2009): 316-319. Academic Search Complete. EBSCO. Web. 5 Aug. 2014.
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Scott, Christopher Thomas. Stem Cell Now: from the Experiment That Shook the World to the New Politics of Life. New York: Pi, 2006. Print.

Thompson, Tanya. “World first as woman gets organ made from stem cells.” news.scotsman.com. Johnston Press Digital Publishing, 18 Nov. 2008. Web. 3 Oct. 2014.
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Stephen Hawking Quote Web. 3 Oct. 2014.
http://www.brainyquote.com/quotes/keywords/stem_cell_research.html#iM2R1JXFolmB71yF.99

Hypoxia and Its Contributions to Regenerative Medicine

Stem cell technology is developing rapidly to bring tissue and organ regeneration from the foreground of current research to the hands of physicians for therapeutic interventions of injuries. Though this field is rapidly progressing, several limiting factors have reduced the efficacy and survival of many transplanted cells. To understand the limitations, a deeper understanding of the chemo–mechanical environment of an injury is needed. Tissue and organ development from specific progenitor cells is tightly controlled by the surrounding biochemical environment. Specifically, oxygen tension, otherwise known as the partial pressure of oxygen, is one of many critical factors playing into the differentiation process of cells into specific tissues. There is a delicate balance between hypoxia (a result of low oxygen tension) and normoxia through the cell life cycle, and this balance varies depending on the biological micro niche in which it resides. Tissue injuries are often accompanied by regions of ischaemia which have proved to negatively influence the survival of transplanted stem cells. This has brought about important adaptations in ex vivo tissue expansion protocol as well as in vivo injury therapies like transplantation of cardiac cells into the hypoxic environment of a recent myocardial infarction or other regions of ischaemic attacks. This review will present the progress of current knowledge on the role of oxygen tension in organogenesis and the significant clinical applications within stem cell therapies. Previously, it has been reported that stem cell fate differs with various oxygen tensions depending on lineage. Here, we first look into the initial uncertainty of the effects of hypoxia and stem cell fate as reported by Cicione et. al. (1) and the metabolic reasoning of the different cellular responses to hypoxia as reported by researcher Munoz et. al. from the Institute of Molecular Biophysics (2). We then look into the investigation by Tanya L. et al. on the effects of oxygen tension in iPS cells which reveals potential significance of hypoxia in cardiac development (3). Finally, we discuss the development and advances of hypoxic preconditioning of cells performed by Uksha S. et. al. (4) and the use of this approach for the ultimate therapy for in vivo application by Xiaofang Y. et. al. (5). Improving stem cell transplant efficiency is of great importance for the advancement of regenerative medicine and current research discussed in this review paves the way for this improvement.
Effects of Severe Hypoxia on Bone Marrow Mesenchymal Stem Cells Differentiation
The natural fate of stem cells can be influenced by the environmental oxygen tension. The goal of this study was to examine effects of hypoxia on differentiation for adipogenic, osteogenic, and chondrogenic lineages from mesenchymal stem cells (MSCs) derived from bone marrow and to see how each lineage differs. Bone marrow is one of the few organs maintained in the hypoxic state, which plays an important role during development and cell differentiation. This unique micro condition prompted researchers to probe into the effects of varying oxygen tension. It has already been demonstrated that in vivo hypoxic conditions for cellular expansion improved mesenchymal stem cell yield and time of expansion to through the chondrogenic lineage. In this particular study by Cicione et. al. (September 2013) (1), bone marrow mesenchymal cells were obtained and isolated from three hip replacement patients. These cells were cultured under standard conditions until the beginning of the differentiation process and characterized using flow cytometry via fluorescent antibody staining. Shortly after characterization, the cells were differentiated down three lineages: adipogenic, osteogenic, and chondrogenic under two oxygen tensions for 14-21 days. Normoxic conditions means that of normal atmospheric pressure with 21% oxygen, whereas hypoxic conditions refer to 1%. The differentiation for each lineage was done with standardized mediums. The results of the study were not uniform for all lineages. The adipogenic lineage under Normoxic condition resulted in a positive stain test for lipid formation whereas the hypoxic condition revealed no lipid formation. This histological outcome was confirmed with qPCR by investigating unique marker genes. The Osteogenic differentiation was initially histologically assessed with calcium deposit staining. Again, the normoxic lineage successfully differentiated as indicated by red staining whereas the hypoxic lineage experienced substantial reduction in differentiation. These results were also confirmed via qPCR for osteogenic markers. The same results followed for chondrogenic lineages. The major findings of this study reinforced the concept that oxygen is a stem cell regulator. Standard in vitro cultures are performed under standard 21% oxygen concentration but normal tissue experiences oxygen pressures between 1% and 13%. This experiment is in agreement with the niche model, which states that stem cells are characterized by a unique microenvironment of low oxygen tension that contributes to maintaining proliferation of stem cells without differentiation. The authors do address the contradicting results with past studies and identify many variable confounding factors between each study. For example, it is generally accepted that chondrogenesis is favored in hypoxia supported by the fact that devascularized nature and subsequent low oxygen tension within cartilage. Although this study clearly demonstrates an inhibitory effect of hypoxia on cell differentiation by observation of a reduction of down the three lineages studied, the fact that previous reports differ warrants further investigation into the mechanisms.
Analysis of Human Mesenchymal Stem Cell Metabolism During Proliferation and Osteogenic Differentiation Under Different Oxygen Tensions
Mesenchymal stem cells (MSC’s) are an important source in bone tissue engineering for grafting. Grafts from these differentiated cells are, at this time, inferior to those obtained from satellite bone within the same patient. This is due to failed survivability of the differentiated and transplanted cells. Munoz et. al. (November 2013), investigated the changes in metabolic phenotype that occur after differentiation from bone marrow mesenchymal stem cells to osteoblasts. The metabolism is significant as the cell metabolic requirements must be met by the resources of its environment. Because these cells are transplanted from a nutrient rich in vitro environment to a site of injury with a reduction nutrients and blood flow there is potential for a disruption in the cell needs. hMSC’s reside in a 2% hypoxic environment which as demonstrated by the previous research, maintains stem cell identity and proliferation in vitro (2). These cells exhibit metabolic production of lactate and are sensitive to to electron transport inhibitors indicating Glycolysis and oxidative phosphorylation as their primary metabolic phenotype. On the other hand, osteoblasts reside in an environment with 5-9% oxygen tension as they are highly vascularized. Osteoblasts respond to oxygen differently with high mitochondrial activity and moderate oxygen supply required. These researchers hypothesize that “osteogenic differentiation is associated with changes in metabolic phenotype, leading to differential responses to changes in oxygen tension”. They utilized gas chromatography–mass spectrometry to profile cells metabolism of 13C-labeled glucose in both hMSC and the hMSC-derived osteoblasts (hMSC-OS) at 2% and 20% oxygen tensions. Metabolites were profiled and allowed for a detailed schematic of cellular metabolism. The metabolic profile for hMSC at 2% reveals an abundance of glycolytic enzymes, increased glucose consumption, and associated lactate efflux. It was confirmed that the cellular metabolism does change after differentiation from MSC to osteoblasts. Hypoxia appears to inhibit glycolytic carbons into the TCA cycle in the osteoblast. The strong connection between glycolysis and TCA cycle in derived osteoblasts relative to hMSC suggests a greater reliance on oxygen availability for osteoblast survival. The results of this study show mesenchymal stem cells metabolism that allow for their own proliferation in a hypoxic environment. Probing into the reasoning behind MSC’s behavior in hypoxic environments aids in the development of and understanding their behavior in ischaemic sites of injury.
Effect of Oxygen on Cardiac Differentiation in Mouse iPS Cells
The ultimate application of stem cell therapies may undoubtedly be that of ex vivo organogenesis. However, just as previously discussed studies have shown, oxygen levels differing from that of a cells natural niche have inhibitory effects on differentiation. At this point, it is known that hypoxia can enhance pluripotency while the effect of hypoxia on differentiation of various cell types can be enhanced or repressed. (The most current literature has mostly focused on the repressive effects). Cardiac organogenesis is one of the areas of study, hindered by this factor. In this particular study, the researchers aimed to understand the effect of Hypoxia Inducible Factor alpha 1 modulated wnt signaling on the differentiation of iPS cells into beating cardiac cells. In the case of cardiac cells, hypoxia is known to cause a myriad of cardiac abnormalities. Hypoxia induced genes like HIF 1 are important in development of cardiac structure and vessel formation. HIF is active under hypoxic conditions and activates genes that respond to a hypoxic environment. Previous studies demonstrated the involvement of HIF in the Wnt pathway. Here, Tanya L et al. (November 2013) hypothesize that “Wnt path may be involved in modulating a cardiogenic response to hypoxia during differentiation”. They investigated role of hypoxia on the differentiation of cardiomyocytes from mouse iPS cells and the expression of genes within the Wnt pathway. iPS cells that were differentiated down cardiac lineages for 14 days of culture under normoxic conditions presented with spontaneous contractions. These embryoid bodies were further characterized to be functional cardiomyocytes. iPS cells were also sent down the same lineage but with short 24 hour bouts of hypoxic conditioning. After 13 days, no cells presented with spontaneous contractions. Hypoxia increased HIF 1 alpha and wnt target genes suggesting involvement of the wnt/beta-catenin pathway, which has a role in embryonic development of axis. The results indicated that hypoxia impairs cardiomyocyte differentiation and activates wnt signaling in undifferentiated iPS cells. This study further expresses the importance of oxygen tension in stem cell differentiation and suggests that hypoxia may play a role in early cardiogenesis.
Preconditioning Stem Cells With Caspase Inhibition and Hyperoxia Prior to Hypoxia Exposure Increases Cell Proliferation
Myocardial infarction is a result of arterial occlusion which results in downstream ischemia, necrosis, dysfunction, and failure. Stem cell therapy on infarct hearts can reduce the magnitude of these adverse outcomes and possible reverse the process of heart attack. With ischemia as the result of reduced delivery of oxygen (hypoxia) in the heart, survival of transplanted stem cells to the injured area is severely reduced. Specifically, the transplanted cells undergo apoptosis rather than self renewal as one may expect based on the previous studies discussed. This is likel;ey due to the fact that the ischaemic environment does not meet the metabolic needs of the differentiated cell. The previous studies described the effects of hypoxic environment on Mesenchymal stem cells resulting in restriction of differentiation. After transplantation however, the major observation is that of cellular apoptosis. Regardless, transplanted stem cell survival is still the main focus. With the ultimate goal of increasing transplant survival, Uksha S. et. al. (November 2013) investigated preconditioning of MSC cells. Here, preconditioning of hyperoxia was used as previous studies indicated positive outcomes by hyperoxygenating the organism during ischaemic attack. The effects of preconditioning of rat MSC’s with hyperoxia or Z-VAD-FMK pan caspase inhibitor or both were studied in a hypoxic environment to mimic the infarct heart. Both methods of preconditioning reduced MSC apoptosis and improved overall cell survival. These cells were not transplanted, rather exposed to an environment similar to that of where they would be transplanted. The following study provides application of preconditioning and real transplantation of cells to an ischaemic injury.
Hypoxic Preconditioning with Cobalt of Bone Marrow Mesenchymal Stem Cells Improves Cell Migration and Enhances Therapy for Treatment of Ischemic Acute Kidney Injury
Xiaofang Yu et. al 2013 demonstrated the improved efficacy of kidney MSC transplant therapy in vivo by means of hypoxic preconditioning of MSC. This type of preconditioning differs from the that of Ukshas’ therapy with hyperoxia and caspase inhibition in that it trains the cells for hypoxia prior to transplant. The particular therapy targeted acute kidney injury characterized by poor renal function. Currently, the only management of such injury is dialysis. The specific need now is renal tubular epithelial cell repair. Though stem cell therapy has shown progress, it has been met with reduced cell survival in ischaemic sites. They used cobalt as a hypoxic mimetic preconditioner by culturing MSC in cobalt for 24 hours. Relative to normoxic conditions the Cobalt hypoxic culture showed increased expression of Hypoxic Inducible Factor alpha and enhanced HMC migration and retention to site of ischemic injury. Additionally, the severity of acute injury was reduced with preconditioned MSC. Blood urea nitrogen and serum creatine, both indicators of acute kidney injury, were present in lower quantities in rats receiving the hypoxic preconditioned cells. This study supports hypoxic MSC conditioning prior to transplantation for increased cell survival in ischaemic regions whose oxygen tension is even lower that the standard tension of that tissue. This particular approach with cobalt induced hypoxia is not particularly useful as cobalt is toxic to mammals. There is need for further investigation into modes of hypoxic preconditioning that are not harmful to the organic system.
Discussion / Conclusion
The need for regenerative medicine is pushing the boundaries of current stem cell research. At the heart of the push is the realized benefits of regenerating tissues. Patients would no longer need to worry about donor match and availability, host-graft rejection, need for use of growth factors, or viral vectors. Physicians could reduce adverse outcomes of an anticipated myocardial infarction or other ischaemic attacks. Myocardial infarction is of particular interest due to such a high incidence worldwide. Though the research discussed has focus on in vivo stem cell therapy, the knowledge can be applied to ex vivo organ synthesis and other stem cell frontiers. The benefits are seemingly endless, but limitations exist that have reduced the survival of cells applied in transplant therapies. Specifically, Oxygen tension has been recognized as a major regulator of differentiation and its effects differ depending on the natural niche of the cell to be differentiated. Understanding how hypoxia plays a role in an stem cells natural environment as well as areas to where they migrate is of critical importance in understanding how such therapy works. In an effort to rationalize the behavior (self renewal) of stem cells in a naturally hypoxic environment, one may consider a reduced oxidative stress.The connection between hypoxia of the natural stem cell niche and the effects of an ischaemic injury on stem cells is not entirely clear. The apoptotic effects of ischaemic injuries on stem cells can be explained by the failure to provide cells with necessary oxygen and nutrient demands based on the changes in metabolic activity associated with differentiation (2). The development of preconditioning of stem cells prior to transplantation has since become a viable option for transplant survival. To date the best strategy promoting stem cell survival after transplant is hypoxic preconditioning. Specifically, intermittent bouts of hypoxic stress followed by normoxia as well as pharmacological induction of hypoxia have proved most effective (5). The mechanism behind such preconditioning brings Hypoxia Inducible Factor (HIF-alpha 1) into question (3). HIF leads to modulation of many genes involved in angiogenesis, mitochondrial respiration and biogenesis, glycolysis, cell proliferation, and cell apoptosis (6). Though hypoxic conditions have been shown to fairly effective at preventing apoptosis and ensuring cell survival after graft, the future of preconditioning lies in pharmaceutical approaches to mimic hypoxic conditions. though Cobalt has this effect, it is toxic to the organic body. This has prompted research into other pharmaceuticals to have a similar and safer effect. Perhaps genetic therapy to induce expression of factors relevant to hypoxic environment is a potential means of preconditioning. Investigation into every aspect which promotes stem cell transplant survival will contribute to the reality of regenerative medicine in clinical applications.

References

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