What are embryonic stem cells?
Stem cells have the remarkable potential to develop into many different cell types in the body. Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the person or animal is still alive. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell.
The definition in English...
Embryonic stem cells are found in infants, and “are blank cells that have the potential to develop into any type of cell in the body – nerve cells, heart cells, and kidney cells” (Berger). For instance, if Johnny happened to get into a car crash and ruptured some of the muscles in his spine, the chances of Johnny someday being able to walk or run would be minimal. However, stem cell evidence suggests that one day in the future, Johnny would be given back the life taken from him. Stem cells would form new spinal muscles, and replace the torn or damaged muscles in Johnny’s spine. In the future, situations like car crashes and the diagnosis of mental diseases will not end a person’s life, because stem cells are showing much
promise in “becoming certain types [of cells]” (Berger). This idea of saving helpless lives is what makes stem cell research a worthwhile endeavor. Now, people are forced to settle into the idea of paralyzation, but the use of stem cells gives them an alternative. It gives them a second chance.
What are adult stem cells?
An adult stem cell is an undifferentiated cell that has not yet generated structures or manufactured proteins of a specialized cell type and is found among differentiated cells. Differentiated cells are the process whereby an undifferentiated embryonic cell acquires the features of a specialized cell such as a heart, liver, or muscle cell in a tissue or organ, can renew itself, and can differentiate to yield the major specialized cell types of the tissue or organ. The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found. Some scientists now use the term somatic stem cell instead of adult stem cell. Unlike embryonic stem cells, which are defined by their origin (the inner cell mass of the blastocyst), the origin of adult stem cells in mature tissues is unknown.
Research on adult stem cells has recently generated a great deal of excitement. Scientists have found adult stem cells in many more tissues than they once thought possible. This finding has led scientists to ask whether adult stem cells could be used for transplants. In fact, adult blood forming stem cells from bone marrow have been used in transplants for 30 years. Certain kinds of adult stem cells seem to have the ability to differentiate into a number of different cell types, given the right conditions. If this differentiation of adult stem cells can be controlled in the laboratory, these cells may become the basis of therapies for many serious common diseases.
What are the cells differences and similarities?
Human embryonic and adult stem cells each have advantages and disadvantages regarding potential use for cell-based regenerative therapies. Of course, adult and embryonic stem cells differ in the number and type of differentiated cells types they can become. Embryonic stem cells can become all cell types of the body because they are pluripotent. Pluripotent cells are when a single stem cell is able to become all of the various cell types that make up the body. Adult stem cells are generally limited to differentiating into different cell types of their tissue of origin. However, some evidence suggests that adult stem cell plasticity may exist, increasing the number of cell types a given adult stem cell can become.
Large numbers of embryonic stem cells can be relatively easily grown in culture, while adult stem cells are rare in mature tissues and methods for expanding 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.
A potential advantage of using stem cells from an adult is that the patient's own cells could be expanded in culture and then reintroduced into the patient. The use of the patient's own adult stem cells would mean that the cells would not be rejected by the immune system. This represents a significant advantage as immune rejection is a difficult problem that can only be circumvented with immunosuppressive drugs.
What I hope we all understand now after reading the above definitions is that there is a huge advantage in using embryonic stem cells over adult stem cells, because they are more adaptable. The problem is though, scientists have a limited supply of embryonic stem cells, because of people like President Bush, and organizations like the Catholic Church and some Christian groups who believe this promising science is inhumane.
Why do they believe this science is inhumane, and as a consequence have severely slowed research?
One of the reasons is that the religious sect believes human/fetal farms will be the cause of the legalization of stem cell research. Human farms, also called "fetal farms" are where human embryos are gestated in a non-human uterus or from human pregnancies and are created specifically for the purpose of research.
What's probably surprising is that I believe the religious sect are right for showing concern towards growing human farms, but their argument using the Bible is weak (What Happened to Separation of Church and State.) Can't we all just agree fetuses, babies--whatever you want to call them--should not be grown to benefit others. There's no need to involve religion. But regardless, just because the government is scared this will be the outcome of the legalization of stem cell research does not justify slowing research and progress. To me, it seems more practical to legalize stem cell research and closely examine the scientists. It's not like these people are incapable of following rules. They are what I would assume to be people of integrity, intelligence, and extreme care considering how many people and organizations have fought to legalize the science. Does the government really think scientists would handle the unrestricted legalization with a disregarding mind and jeopardize the entire fields public image? If so, that's pretty sad.
Berger, Eleni "Research Avenue Adds Fuel to Stem Sell Controversy." 18 July 2001. CNN.com. CNN. 25 Oct 2004
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