Magazine, website & books written by teens since 1989

Adult Stem Cells vs. Embryonic Stem Cells

Custom User Avatar
More by this author
Cancer, Alzheimer's, diabetes, sickle-cell anemia, Parkinson’s: these are just a few of the things that stem cell therapy can solve. Many governments also view ASC and ESC research as a way to bolster the economy through biotech-industry development. Stem cell therapy is an experimental procedure with endless possibilities due to the singular ability of stem cells to change into other cells. However, since only the embryonic stem cells are pluripotent, meaning they can change into any cell, scientists generally favor research on embryonic stem cells (ESCs). This leads many people to wonder whether it is morally acceptable. What they don’t know is that there an alternative to ESCs exists: adult stem cells (ASCs). These stem cells provide a solution to the medical and moral problems associated with ESCs. The question, therefore, is not “Should stem cell research be allowed?” but rather; how exactly could ASC research be more beneficial than ESC research?

It is first essential to realize that ASC therapy is a viable alternative to ESC therapy. Adult stem cells “’have important advantages for regenerative medicine over embryonic stem cells and induced pluripotent stem cells in that they are easily accessible from any patient and don’t cause immunological problems, they don’t cause tumors and they don’t have ethical problems,’ said Charlene M. Cooper, Vice President and Chief Operating Officer of AntiCancer.” (Health & Beauty Close-Up). This quote about sums up the benefits of ASC research and simplifies the matter immensely by solving so many of the problems that ESCs caused. The recipient’s immune system could reject the ESCs because of the different DNA, and many religions don’t support ESC research because it involves destroying the embryos, which they equate to murder. With ASCs, the stem cells would be taken straight from the patient’s body and therefore would not be rejected by the immune system, and it does not bring up questions of morality. Many conservative Christians believe that the embryos "have the same moral standing as adult humans and must not be used in researh to which they, obviously, cannot consent" (Clemmitt). This belief has been the basis of many laws which protect embryos from experimentation. Because the research destroys the embryos, they are protected by at least 36 state laws which "criminalize fetal homicide," 15 of which "apply to the earliest stages of pregnancy--immediately after fertilization" (Clemmitt). It should be kept in mind, however, that lawmakers are not scientists, and may be unable or unwilling to take into consideration the full medical benefits. However, these laws are backed up by the so-called snowflake children who were born from unused in vitro fertilization (IVF) embryos that had been given up for adoption by the couples who created them. The snowflake kids are widely seen as proof that the embryos which scientists want to use for research do have the potential to grow up into normal human beings. Despite the reality that most frozen IVF embryos will most certainly die anyways, a significant number of people still believe that this is no excuse to experiment on them. According to Gushee, "People on death row are going to die anyway. So why not experiment on them, even if those experiments involve killing them? After all, we might as well get some good use out of them. The same thing could be said for, say, millions of people with terminal illnesses, or in nursing homes in their very last days." Most opposers of ESC research, however, have no qualms with ASC research. In fact, the FDA has approved of nine ASC treatments, though supporters of ASC research claim that more than sixty possible treatments have proven effective. Another problem with ESC research is gaining funding, for some people say that it's "inappropriate to use tax dollars to fund research that a significant number of taxpayers oppose" (Clemmitt). Also, scientists say that since the normal function of ASCs is repair, they are more useful than ESCs in helping patients with diseases and injuries. Furthermore, as of 2006 there are "72 clinical human trials... where ESC researh has not yet reached the clinical trial stage" (Clemmitt). Recent research into ASCs have also come up with fascinating possibilities for ASCs. For example, ASCs in bone marrow, which for a long time were believed only to be able to create new blood cells, may actually be able to create different types of tissue. They also could play a major role in curing cancer; it has been discovered that some cancer cells pump out a protein that fights off chemotherapy, and that this same pump exists in stem cells. This suggests that cancer "is a disease of tissue specific stem cells," says Emerson. ESC research is still in it's early infancy and scientists as yet cannot produce specific types of tissue with the ESCs, but only make several different cells, perhaps with one predominating. ASC research is not inhibited by moral viewpoints or by a limited knowledge as ESC research is. Therefore, presently ASC research is favored by more religious denominations and lawmakers.

However, the current shortcomings of ESC research could be attributed to its relative infancy in comparison with ASC research. Scientists have been researching ASCs for more than 20 years, while ESCs only entered the science in 1998. Many biologists insist that ESC research could play a vital role in understanding how humans develop and in curing or treating several degenerative illnesses. Gaining the embryos for the research would present no challenge seeing as how more than 400,000 have been frozen and stored since the late 1970s, while the couples who created them are unlikely to use them. Supporters of ESC research say that it is justified because the potential medical benefits could save the lives of thousands of people in the future. Pluripotent cells are cells with the ability to change into the more than 200 different types of cells in the human body, making them especially valuable to possible therapies. Unfortunately, as far as we know today, these cells are found only in the center of the blastocyst, in ESCs. This is a main reason why many people are opposed to ESC research. However, some people believe that ESC research might not have raised the opposition that it did if scientists had not been researching cloning at the same time. Most religious denominations have the same problem with ESC research as they do with cloning: they believe it to be morally wrong. Despite their opposition, ESCs could provide real benefits to medicine. For instance, ESC cultures could provide a new way to test experimental drugs on the exact cells that those drugs are intended to effect, which today is not possible. This could eliminate altogether the need for animal testing. ASCs are extremely difficult to work with due to several problems, one of which includes the difficulty in keeping them alive in the lab. Also, after the ASCs are removed from the patient's body, "they often must be propagated in tissue culture for long periods of time before transplantation back into the patient. That's impractical from a clinical standpoint and can lead to potentially damaging changes in the cells" (Clemmitt). Also, most treatments including ASCs remain unproven and still need validation. Scientists are very limited in their ability to use ASCs. While they do hold great potential, there is not much data supporting ASCs. Most of the data comes from small trials which have yet to be verified by other labs. Furthermore, "adult stem cells don't provide researchers the kind of flexibility that embryonic stem cells do, since they are already formed" (The America's Intelligence Wire). And if this weren't enough, ASCs are also extremely difficult to find in th body because they are scattered all over among the other cells. There aren't very many of them in any one place. Even though scientists have been studying ASCs longer than they have ESCs, still very little is actually known about ASCs. In fact, when it comes to ASC therapies, the bone marrow therapy is the only one that has really worked with any amount of consistency so far. Based on these facts, ESC research is, medically speaking, the better and more beneficial way to go.

Unfortunately, no matter what the medical benefits, the moral dilemma is still a very real problem. Ideally, shifting the scientific focus to ASC research would solve all of the moral problems associated with ESC research, but we do not live in an ideal world. To disclude ESC research simply because of religious qualms would disturb the scientists, as they believe that "research on all kinds of stem cells is required" (Clemmitt). Even if ESC research in the US was suspended, it would continue uninhibited in other countries. ESC research cannot be allowed to continue, but at the same time it must not be stopped. As a result of this stalemate, several compromises have arose. One of these compromises includes cloning. If a patient was in need of some sort of ESC therapy, a clone would be created but left as an embryo from which ESCs could be extracted. In this way, scientists would still have embryonic stem cells to work with, but the original would have already grown up and would not have to be destroyed. However, "implementing such cures would require cloning embryos for the sole purpose of destroying them" (Clemmitt), which is something that those opposed to ESC research cannot abide by. Another possibility involves "deriving cells from blastocysts that are found to be 'organismically dead,' because they've lost the capacity for the integrated, continued cell division and differentiation needed to produce a viable fetus." This would be a viable compromise except that it severely limits the number of ESCs with which scientists could work. Also, scientists hope to gain more insight into the development of humans by the study of ESCs, and organismically dead blastocysts would not be able to privide the data required to meet these ends. Still another compromise, called altered nuclear transfer or ANT, would be a twist on cloning. "An unfertilized egg cell would be implanted with DNA that lacks few of the elements needed to develop into a full organism" (Clemmitt). Unfortunately this still does not solve the moral dilemma because researchers would be purposefully taking away the ability of the zygote to develop into a human life, which is unacceptable in the eyes of many religions. Also, it leads many to fear that women would be coerced into donating millions of their eggs to the research. A final compromise is to create human ESCs by inserting the nuclei from human skin cells into rabit eggs. This, by far, is the best compromise of them all. It raises no questions of morality because the embryos which scientists would be working with would be artificially created clones, the life and development of which is not morally acceptable. Furthermore, no human eggs would be involved in the creation of these embryos. This compromise would seem to placate both sides. However, it raises the fear in many of creating chimera, human-animal hybrids. As such, this research program has been banned in many countries, including the United States.

Thus the question arises, is there any way to satisfy both sides of the argument? The answer: no. Not presently, anyway. However, there is hope for the future to eliminate the need for ESCs. Scientists hope to learn enough about how ESCs turn into ASCs to be able to turn ASCs back into ESCs, or at least to return to them the potential that they once had to produce any kind of tissue. Once we can do this, there will be no more need of ESCs. As a matter of fact, scientists at Japan's Kyoto University claim to have accomplished this already with mouse ASCs. But one test with mice is a far cry from a viable alternative for humans. As of yet there is still much knowledge to be obtained from ESC research. Those opposed to ESC research will say that any research on ESCs is unacceptable because it will still be destroying human lives. But without that knowledge, we will never be able to find the right genetic pathways that will trigger an ASC-to-ESC conversion. Therefore, if we ever hope to reach the point where we no longer need ESCs, then research on them must be allowed to continue, if only for the time being.



Post a Comment

Be the first to comment on this article!




Site Feedback