Introduction
Stem cells are immature cells which are mostly found in multi-cellular organism and they are mainly characterized by their ability to renew through mitotic cell division which later differentiates into ranges of various specialized cell types (James, 2004, p39). Stem cells in mammals are classified into two broad classed that is embryonic stem cells which are mainly found in blastocyst and adult stem cells and these are from adult tissues. Each category plays specialized role since for embryonic stem cell they usually differentiate to form various embryonic tissue whereas those of adult stem cells work together with progenitor cells to repair various systems in the body.
Discussion
Stem cell research is quite important in many issues which regards to human body. The research which has involved mainly the scientists want to make use of stem cell’s ability to differentiate into many cells in treating various diseases such as Parkinson disease, diabetes, Alzheimer or head condition. They also believe that the research can enable them test drugs sensitivity and they can also develop other types of drugs. Productive and cell biology knowledge can also be gained by vast research made on stem cells. Basically, stem cell research has great potential of improving human health by use of stem cell therapy.
It has been noted that most of diseases are mainly caused by premature deaths of cells or other malfunction within various cells in human body. For example, Parkinson’s disease and Alzheimer’s diseases occur when the brain cell dies, they cause type diabetes (Popular Issues, 2002). With research, most scientist have believed that therapy of the stem cells can result to revolutionary way of treating there deadly diseases by repairing those body tissues that are diseased and damaged and generating healthy ones for replacing them. A lot of research is needed to evaluate how various stem cells work so that a way can be invented on how to treat their conditions.
There are quite a number of pros and cons of stem cell research in human. Despite the fact that they are quite useful when they are developed, there are often negative aspects that they bring which endangers the lives of human that undergo therapy of stem cells. Also, in ethical grounds stem cell research is not much valued which has led to many grounds both governmental and non-governmental to object the issue of research.
One major pro of stem cells is that it can be contrasted with differentiated cells whereby there is much hope offered for the advancement of various medical fields. They have high ability to differentiate and grow into any kind of cell in human body. For instance, when neural cells which are mainly found in spinal cord and in the brains, they can be replaced by cells generated from stem cells. More also, diseases such as cancer when they are treated by chemotherapy or radiation it leads to huge damage of those cells and they are destroyed and eliminated from the body. Through stem cell research new cells can be generated which are used to replace the destroyed ones and they can easily adapt to the affected area which brings back the normal functioning of the body. Dead cells which occur as a result of injury or disease, they can be replaced into new healthy cells in any part of the body which is taken to the normal functioning of the body. Therefore stem cells are found to be quite flexible.
In another instance, to have clear understanding of various pros and cons of stem cell, one should have clear knowledge on the sources of these cells. Stem cells can either be obtained from adult, embryonic or cord cells. For adult cells, they are mainly obtained from the bone marrow. The procedure of extracting these cells is quite painful which results to a lot of objection by many individuals. Within the peripheral, the procedure is not quite painful but a lot of time is taken in extracting these cells. They are quite difficult to extract since their cells are taken from patient’s own body. Adult’s stem cells are very plentiful and quite superior to embryonic and umbilical cord cells. They have an exact DNA match which increases their compatibility rate in the body and thus they cannot be rejected by the immune system.
Those stem cells which are extracted from the umbilical cord are also very rich in stem cells. They have showed a high degree of offering a perfect match where family has been earlier planned. These cells are extracted during pregnancy and they can be stored for insurance purposes of the newborn in cryogenic cell bank. These cells can be used by either the mother or the father or any person (relative)
Compatibility of these cells is mainly determined by the distance of relationship between newborn and other relatives. The further the relationship, the ore likely the cells are going to be rejected by the immune system antibodies of the person who has used these cells. However, there are other cord cells which are quite common to individuals and can be compatible to anyone just like blood group. Volunteer donors donate their cells which can be used by recipients when they are found compatible. Umbilical cells donation is encouraged greatly since it is the richest source of stem cells which can be donated and stored by pregnant mothers and they are always available when they are needed. When these cells DNA cannot match that of donor and recipient, scientists have developed a way to increase compatibility by increasing transferability and reducing risks.
Embryonic stem cells are extracted before the embryo’s cells begin to differentiate from the blastocyst. There are quite a number of cells in blastocyst whereby the largest percentage of these cells are stem cells. These cells are kept alive indefinitely and they are grown into culture and have the cell differentiate actively doubling their number every 2-3 days (James, 2004, 40). When cells replicates from a single blastocyst, they are called stem cell line since their genetic materials are same and they come from a same egg that has been earlier fertilized.
Therefore, on ethical grounds it is believed that human life begin from the time an egg became fertilized and so those who value human life have greatly opposed the idea of embryonic stem cell research. Since when stem cells are extracted from the embryo, it means that the embryo needs to be destroyed in order to facilitate research and obtain the cells. This has been valued as taking away of human life which has been seen as murder (Popular Issues, 2002). Embryonic research has revealed that the tiny blastocyst have no elements of human features and further studies shows that there are new stem cell lines, which have existed as a result of in vitro fertilization (IVF). According to research, it has been noted that there are many fertilized human cells that are already banked today but they are not being used for research and for ethical purpose. Many have advocated that new human life should not be claimed at the expense of experimentation.
Some research have revealed that when mice were used for experimenting embryonic stem cells in treatment of Parkinson diseases, it revealed that some mice which were treated with the embryonic stem cells eventually died as a result of tumor which developed on the brain (David P. 2005). It has also been noted that when embryonic stem cells are stored for a long time, they develop chromosomal abnormalities which eventually result to cancer cells. Therefore, for quite good reasons, funds that are used for research in embryonic stem cells can otherwise be used in better ways by funding the adult and the umbilical cord research which have been proved to be very useful in the lives of many.
When these cells are classified as mature and early human cells where mature cell comprises of both adult and umbilical cord stem cells and early human stem cells as embryonic cells, there are a number of advantages and disadvantages which each category has.
In the case of mature cells, there is no likelihood of immune response occurring since there one’s own cells which are made to replicate in order to perform the function of those which have been destroyed. In the case of early stem cells, immune rejection is highly experienced whereby the stem cells, immune rejection is highly experienced whereby the stem cells are not compatible to the recipient. This happens because the stem cells are derived from the blastocyst and they are created through IVF.
Mature stem cells are very available for use at the time that they are needed as compared to early stem cells which mean that life has to be taken in order to make these cells available. The mature stem cells are mainly obtained from the patient.
The mature stem cells are very specialized which makes them to require little coaxing so that they can be developed to specialized stem cells that are desired. Whereas in the case of early stem cells, there are so many steps which are required to coax the cell so that if it can be desired cell type and this may be difficult to control in most cases.
The mature stem cells have limited longitivity which results to failure to maintain the cell cultures in their active state for a long time. In the case of young cells, they are immortal since their cell lines remain intact long enough and this allows them to produce endless number of cells. It is quite difficult to find stem cells extract from the mature cell in the case of mature stem cells while it is quite easy to extract these cells in the young stem cells.
The young stem cells are pluri-pontent which gives it ability to differentiate and making any cell in the body whereas those of mature stem cells they are multi potent and they have limited flexibility and this hinders it ability to become any body cell type. The mature stem cells are quite uncommon and as one ages, their cells become scarcer in the body. For the young stem cells, they are readily available since many blastocysts for research are readily available today which have been acquired through IVF while other new methods such as somatic cell nuclear transfer (SCNT) are coming up to help with the research. With the invention of this technology there is no high risk of immune rejection because this will enable patients to use their own cells (Cowan, 2004, 1354).
The human pluripotent stem cells which are mainly found from the embryonic and fetal tissue. The embryonic stem cells can divide indefinitely which forms cells of the three major tissues, endoderm, mesoderm and ectoderm. The endoderm forms the lining of the gut, pancreatic and liver cells, whereas the mesoderm is responsible for formation of muscle bones and blood and the ectoderm gives rise to nervous system and the epidermal tissue. The adult stem cells are multi potent and therefore they end up developing into tissues of their own origin.
Both pluripotent and multipotent stem cells can be used for either clinical or research work. The cells can be stimulated to enable them develop into specialized stem cells which can have renewable sources which can generate cells and tissues which can be used for transplant (Probhaka 2008). The act of using stem cells to replace the damaged cells, the therapy is very practical to injuries and other genetic and degenerative conditions. Some conditions such as muscular dystrophies and retinal degeneration can be treated by the use of stem cells therapy. This condition requires the use of stem cells in areas where destruction of the original cells has taken place which picks up the functioning of these cells.
Stem cells research can enable one to come up with an ideal way of identifying various factors that results to differentiation of stem cells to become more specialized cell type. The factors which are identified can be used to drive tissue regeneration and repair of various damaged tissue if they are given therapeutically. More also, valuable biological information can be acquired which relates to development of human being, genomic imprinting and also somatic cell aging are valuable information that can be acquired when research is carried on the study of the human pluripotent stem cell.
The research can also advance various ways of development and testing drugs for safety. Researches can base their research on toxic and non-toxic effect of various drugs on pluripotent stem cells which have already been developed and this can reduce various disease processes. Drugs that proves to be safe in cell line are the ones that can be tested further in laboratory animals and finally to human.
Therefore to summarize it all there are a number of advantages and disadvantages which are summarized as follows:
Advantages of stem cell research
- It is of medical benefit since it provides therapeutic cloning and plays a vital role in regenerative medicine
- Many diseases and injuries can be treated using stem cells
- Limbs and other organs that are used for transplant can be grown in laboratories
- Has helped scientist in learning about cell development and human growth
- Drugs and medicine sensitivity can be tested on cell lines before they are administered to patients
- It has also helped scientists to study stages of development in embryo which can not be studied in real life. They can also study clinical consequences such as various birth defects, miscarriage or source of infertility
- It can hold a key to reversing various effects of aging and prolonged lives. It has revealed that there are some treatments which are used to reverse the effects of aging.
- Advantage of using adult stem cell is that one can specifically use his or her own cells which are not likely to face rejection by immune system.
Disadvantages of stem cell research
- when embryonic stem cells are used it means that blastocyst have to be destroyed and this turns out to be immoral and unethical to those people who believes that life begins at conception
- since stem cell research is a new technology, the long term effect of this has not yet been known since it can result to interference with what is natural
- Use of embryonic stem cells may not be solution to many or all ailments.
- In a resent research it was found out that when stem cell is used to treat heart disease, the coronary artery can end up being narrower which increases the risk of heart failure
- For adult stem cells, they are pre-specialized which means that some cells are limited to creating cells of a specific origin example Brain cells create only stem cells of brain.
- For embryonic stem cells they can face rejection by the immune system since they are not derived from patients own cells.
Conclusion
Therefore stem cell research has both advantages and disadvantages. But since much research is underway it is believed that it will create solution for many diseases, injuries and disability with minimum negative effect on the immune system of the individual. It has been noted that stem cell research will bring about new changes in life which are necessary in our lives today.
References
David P, The Real Stem Cell Research, 2005, HealthNewsDigest.com
Cowan C. A., Stem-Cell Lines, 2004, New England Journal of Medicine, p.1355-1356.
Probhaka P., Advantages and Disadvantages of stem cell research, 2008, Web.
Popular Issues, Pros and Cons of stem cell research, 2002, Web.
James M., Stem cell research, 2004, Humana press New York, p 34-57.