Advantages and Disadvantages of Stem Cell Research

Human stem cell research still remains one of the widely debated topics in the clinical and political circles. The proponents and opponents of stem cell research have strong arguments defending their stance, and there is still a lot of ambiguity on this issue. Let us take a look at some advantages and disadvantages of human stem cell research.

Most of us may have a general understanding of the controversy surrounding stem cell research but we may be ignorant about the specific issues that have made this one of the most sensitive topics of our time. There are many advantages and disadvantages of stem cell research but before studying them, it is important that we get a primer on what exactly is stem cell research. Stem cell research focuses on stem cells, which have a capacity to regenerate. A stem cell is capable of developing into other types of cells, like kidney cells, liver cells, heart cells, etc. Stem cells circulate and function to replace dysfunctional cells, naturally maintaining optimal health. Current medical research is focused on two particular types of stem cells - adult and embryonic. Out of the three types of stem cells, two are able to develop into any type of cell within the human body. These two are called totipotent and pluripotent respectively. Stem cells that are pluripotent have the capability of forming virtually all the possible tissue types found in human beings. These stem cells can only be found in a particular stage (a blastocyst) in human embryos. Multipotent stem cells are partially differentiated, so that they can form a restricted number of tissue types. Multipotent stem cells can be found in the fetus, in numerous adult tissues and umbilical cord blood. The third type of stem cells have less regeneration potential and can only develop into a limited number of other types of cells. Advantages of Stem Cell Research

It provides medical benefits in the fields of therapeutic cloning and regenerative medicine. It provides great potential for discovering treatments and cures to a plethora of diseases including Parkinson's disease, schizophrenia, Alzheimer's disease, cancer, spinal cord injuries, diabetes and many more. Limbs and organs could be grown in a lab from stem cells and then used in transplants or to help treat illnesses. It will help scientists to learn about human growth and cell development. Scientists and doctors will be able to test millions of potential drugs and medicine, without the use of animals or human testers. This necessitates a process of simulating the effect the drug has on a specific population of cells. This would tell if the drug is useful or has any problems. Stem cell research also benefits the study of development stages that cannot be studied directly in a human embryo, which sometimes are linked with major clinical consequences such as birth defects, pregnancy-loss and infertility. A more comprehensive understanding of normal development will ultimately allow the prevention or treatment of abnormal human development.

Another advantage of stem cell research is that it holds the key to reversing the effects of aging and prolonging our lives. Stem cell research has already found many treatments that help in slowing the aging process, and a bonus of further stem cell research is a possible 'cure' for aging altogether. An advantage of the usage of adult stem cells to treat disease is that a patient's own cells could be used to treat a patient. Risks would be quite reduced because patients' bodies would not reject their own cells. Embryonic stem cells can develop into any cell types of the body, and may then be more versatile than adult stem cells.

Disadvantages of Stem Cell Research

The use of embryonic stem cells for research involves the destruction of blastocysts formed from laboratory-fertilized human eggs. For those people who believe that life begins at conception, the blastocyst is a human life and to destroy it is immoral and unacceptable. Like any other new technology, it is also completely unknown what the long-term effects of such an interference with nature could materialize. Embryonic stem cells may not be the solution for all ailments. According to a new research, stem cell therapy was used on heart disease patients. It was found that it can make their coronary arteries narrower. A disadvantage of most adult stem cells is that they are pre-specialized, for instance, blood stem cells make only blood, and brain stem cells make only brain cells. These are derived from embryos that are not a patient's own and the patient's body may reject them.

Truly, the controversy over human stem cell research will continue to rage furiously. We hope there is some novel scientific innovation in the future, which will have the advantages of stem cells without compromising the right of human life to exist. One should realize that man should control technology and certainly not the other way round.

By Prabhakar Pillai Last Updated: 12/22/2011

http://stemcells.nih.gov/info/basics/

Stem cell research is a relatively new technology that takes primitive human cells and develops them into most any of the 220 varieties of cells in the human body, including blood cells and brain cells. Some scientists and researchers have great hope for this research and its ability to uncover treatments and possibly even cures for some of the worst diseases including heart disease, diabetes, and neurodegenerative diseases like Alzheimer's and Parkinson's. Along with these hopeful possibilities, stem cell research also gives rise to fear of human cloning and serious concerns over the ethics of conducting scientific research on, which includes the destruction of, human embryos.

Types of Stem Cells

Human stem cells primarily come from embryos or adult tissue. Embryonic stem cells can be created solely for the purpose of stem cell research or they can be the leftover from other processes, such as from in-vitro fertilization (IVF). Fertility treatments usually result in the creation of multiple embryos, and since only the most viable are selected for implantation, some embryos are not used. These extra embryos can be discarded, donated to others seeking fertility assistance, preserved, or donated to research; most commonly, leftover embryos are discarded. Adult stem cells can be harvested from adult tissue with minor, if any, harm to the adult. Embryonic stem cells, however, are said to be generally easier to extract than the adult stem

cells, and embryonic stem cells are said to have more uses than their adult counterparts. Much of the stem cell research debate centers on embryonic stem cells because of their potential uses, and because of questions about when life begins.

Ethical Issues

The overall debate over the ethics of stem cell research involve two major ethical concerns: (1) the potential for human cloning, and (2) whether these embryos, or pre-embryos as some refer to them, are human life. Perhaps the initial controversy is related to the possibility of human cloning. Especially when it first gained popularity, researchers were concerned with the potential for using stem cells to clone humans. Proponents make many arguments in support of human cloning including the possibility of creating another you should body parts or tissues be needed later in life as one may develop illnesses and diseases. Opponents primarily argue that it is not within mans judgement to manufacture, manipulate, or destroy human life. The other major ethical issue related to stem cell research involves the ongoing debate over when life begins. Some say that life begins at conception and that the use of humans, even immature ones, for research purposes is unethical. Others claim that the embryos are only tiny amounts of undifferentiated tissue and since they are already scheduled for destruction, and have great potential benefit, they should be used to potentially help others.

Legal Differences
It is legal to conduct stem cell research in the United States, even for the purposes of human cloning. In 2001, President Bush authorized the issuing of federal funds for the research of over 60 existing stem cells lines. The funding was restricted to these cell lines because the issue of life and death was already decided; that is, the stem cell lines at that point were capable of independent and infinite regeneration. In 2009, President Obama reversed the policy and allowed federal funding to be used towards additional stem cell lines. Other countries permit stem cell research to varying degrees. Countries such as Japan, Sweden, and the United Kingdom have made it legal, even for purposes of human cloning. Countries including Australia, Canada, and France allow adult and leftover embryonic research but not human cloning. Austria, Ireland, and Poland have some of the most restrictive laws on this type of research.

What are the similarities and differences between embryonic and adult stem cells?
Human embryonic and adult stem cells each have advantages and disadvantages regarding potential use for cell-based regenerative therapies. One major difference between adult and embryonic stem cells is their different abilities in the number and type of differentiated cell types they can become. Embryonic stem cells can become all cell types of the body because they are pluripotent. Adult stem cells are thought to be limited to differentiating into different cell types of their tissue of origin.

Embryonic stem cells can be grown relatively easily in culture. Adult stem cells are rare in mature tissues, so isolating these cells from an adult tissue is challenging, and methods to expand their numbers in cell culture have not yet been worked out. This is an important distinction, as large numbers of cells are needed for stem cell replacement therapies. Scientists believe that tissues derived from embryonic and adult stem cells may differ in the likelihood of being rejected after transplantation. We don't yet know whether tissues derived from embryonic stem cells would cause transplant rejection, since the first phase 1 clinical trials testing the safety of cells derived from hESCS have only recently been approved by the United States Food and Drug Administration (FDA). Adult stem cells, and tissues derived from them, are currently believed less likely to initiate rejection after transplantation. This is because a patient's own cells could be expanded in culture, coaxed into assuming a specific cell type (differentiation), and then reintroduced into the patient. The use of adult stem cells and tissues derived from the patient's own adult stem cells would mean that the cells are less likely to be rejected by the immune system. This represents a significant advantage, as immune rejection can be circumvented only by continuous administration of immunosuppressive drugs, and the drugs themselves may cause deleterious side effects

An unborn human baby, esp. in the first eight weeks from conception, after implantation but before all the organs are developed.