Research on stem cells has provided valuable knowledge and information about an organism develops from a distinct cell and how healthy cells can substitute damaged cells in adult organism. Stem cells are one of the most intriguing areas of biology today. But like many expanding fields of scientific inquiry, researches on stem cells have raised many scientific questions as fast as they generate new discoveries. Stem cells possess two important characteristics that helps differentiate them from other types of cells. First they are unspecialized cells that have the ability to renew themselves for long periods through cell division. The second is that under certain physiologic or investigational conditions they are induced to become cells (Malcolm Alison et al, pp-599-603). There are two kinds of stem cells used by scientist and are from humans and animals, they include; embryonic stem cells and adult stem cells.
Stem cells in developing tissues give rise to the multiple specialized cells types that make up body organs. In some adult tissues such as bone marrow muscle and brain generate replacements for cells that are lost through normal wear and tear, injury or diseases. Scientist belief that these stem cells will at some point in future become the basis for treating diseases such as Parkinson’s disease, diabetes and heart diseases. Scientists want to study stem cells in the laboratory so as to get more insight about their essential properties and what makes them different from the specialized cell types (Washington D.C national academy press 2002/3). As scientists learn more about stem cells they are optimistic that it may become possible to use the cells not only in cell-based therapies but also for screening new drugs and toxins and understanding birth defects
Stem cell research should be encouraged and supported by all means.
Studies of human embryonic stem cells may yield information about the complex events that occur during human development (James A. Thomson et al, pp. 1145-11) Stem cells research aims at identifying how undifferentiated stem cells become differentiated bearing in mind that it is the genes that are solely responsible for these processes. Scientists also belief that most serious medical conditions, such as cancer and birth defects, are as a result of unusual cell division and differentiation better understanding of the genetic and molecular controls of these processes may reveal more information about how such disease come about as well as suggesting new strategies for therapy. A significant hurdle to this one and most other uses of stem cells is that scientists have not yet understood the signals that turn specific genes on and off to influence the differentiation that occurs in these stem cells.
The opponents of stem cell research say that the bone of contention is not the intended use of these stem cells but the source of stem cells themselves. This is because stems are developed from the developing embryo’s which are destroyed before they could develop fully into an infant. The Catholic Church who is the major opponents feels that it is immoral and unethical to destroy life of one inorder to safe that of another. However the researcher’s usage of embryos is justified since most of them which are produced through In-vitro fertilization (IVF) are never taken up by their owners, but are otherwise thrown away. Researchers feel that using them for research is better than being thrown away.
Studies on stem cells should further be supported since human stem cells could also be used to test new drugs for example. Newly constituted medications could be tested for safety on differentiated cells generated from the stem cells. Currently the cancer cell lines for examples are used to screen potential anti-tumor drugs but the availability of pluripotent stem cells would enable drug testing in a wider range of cell types: however to screen drugs effectively, the conditions must be identical when comparing different drugs. Therefore scientist will have to be able to precisely control the differentiation of stem cells into the specific cell type of which drugs will be tested. However much research needs to be done to understand the signals controlling differentiation since presently they are not fully understood. This will help to clearly and accurately identify the conditions and to consistently have identical differentiated cells for each drug being tested.
Those opposing this research propose that there are other animals that are closer to human beings like mice and primates which can be used to test the drugs instead of the use of human stem cells. However, Animal experimentation has always been used but its usage has only focused on artificially created pathology that does not consider other confounding variables. Animal experimentation studies are thus undermined by differences between human and non human anatomy physiology and pathology. These researchers argue that using animals to test on drugs to be used by humans is an inherently unsafe method to investigate human disease processes. Much resource has been wasted in the past in animal experimentation since these animals are so different from human and react differently to these drugs. Some drugs have been recalled /with drawn from the market since they have been found to have adverse effects to humans although they tested safe to animals during testing. Therefore the only sure way to test the efficacy of a drug/ medication to be used by humans is by testing with human stem cells.
In addition, human stem cells can be used in the generation of cells and tissues that could be used for cell-based therapies. For this to be achieved more stem cell research should be carried out. Currently donated organs and tissues are often used to replace ailing as well as destroyed tissues but the need for these transplantable tissues and organs is very high compared to the available supply.therefore, unless another alternative source of these organs is obtained, many lives of people could be lost who may otherwise be saved. Stem cell offers a viable alternative and thus should be supported and encouraged by all stakeholders, the church inclusive. Stem cells directed to differentiate into specific cell types offer the possibility of a renewable source of replacements cells and tissues to treat diseases including Parkinson’s and Alzheimer’s diseases, spinal cord injury stroke, burns, heart diseases, diabetes, osteoarthritis and rheumatoid arthritis. For example it may become possible to generate a health heart muscle cells in the laboratory and then transplant those cells into patients with chronic heart diseases. A preliminary research in mice and other animals has indicated that bone marrow stem cells transplanted into a damaged heart can generate heart muscle cells and successfully repopulate the heart tissue (Natalie C. Direkze et al. 21:514-520) Other recent studies in cell culture systems indicate that it may be possible to direct the differentiation of embryonic stem cells or adult bone marrow cells into heart muscle cells. However to realize all these cell- based therapies for such persistent and incapacitating diseases, scientist must be able to easily and reproducibly manipulate stem cells so that they posses the necessary characteristics for successful differentiation transplantation and engraftment (Hogen Brigid, http://www.hhml.org)
.However the opponents argues that if this research is supported it will lead to increased case of assisted reproduction such as In-vitro fertilization (IVF). Led by the Catholic Church faithful they feel that this will lead to human cloning. Cloning is defined as “the process by which one produces another being virtually genetic replies if an existing human being” they feel that these procedures are morally impermissible and should never be practiced. The church argues the conception of a child should be from a loving interpersonal sexual intercourse between a man and a woman. However the major objective of ‘stem research is not assisted reproduction or cloning but to assist scientist in identifying how undifferentiated stem cells become differentiated and generation of cells and tissues to be used for cell-based therapies.
James A. Thomson et al, Embryonic stem cell lines derived from human blastocysts
Science (1998) pp. 1145-11
Natalie C. Direkze et al multiple organ engraftments by bone marrow- derived
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Malcolm Alison et al, plastic adult stem cells. Will they graduate from the school
Of hard knocks. Journal of cell science, (2003) pp-599-603
National research council stem cells and the future regenerative medicine (Washington
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