Cells, Mouse (Embryonic)

STEM CELLS ARE a special variety of cells that have been identified in some multicellular organisms. Most of the cells in the body transform into and reproduce only the parent cell type; stem cells, in contrast, have the capacity to transform into multiple cell types throughout their life spans. We also know that stem cells are of two types—adult and embryonic. As the name indicates, adult stem cells are found in adults and serve to replenish cells in certain parts of the body where they are lost because of a continuous turnover for a variety of reasons.

Examples of such tissues include skin, bone marrow, and the lining of gastrointestinal tract, and so [Page 82]forth. Embryonic stem cells, in contrast, are found in the body at a very early stage of its development and play an important role by forming different tissues of the body.

Since the 1960s, when the presence of stem cells was first elucidated in some cancers, these cells have been the center of attention for scientists. However, it was only in 1981 that researchers were able to isolate these cells in tissues derived from mice; since then, murine models have been a major source of our understanding regarding the functioning of these fascinating cells. Mouse stem cells have provided invaluable information regarding how stem cells proliferate and are affected by different external, as well as internal, growth factors during the process of differentiation. These growth factors, which are mainly proteins in nature, affect stem cells' behavior at different stages. Because there is a lot of similarity between the DNA of mice and that of humans, the two species make excellent candidates for research and help us appreciate the ways they might work in human beings. Furthermore, mice offer the advantage of being raised at a lower cost with relative ease and do not need any special environment when compared with other animal models. They also have a short generation time, thus enabling researchers to study successive generations with respect to a particular trait or disease without having to wait for long periods of time.

The photo shows a human embryonic stem cell colony on a mouse embryonic fibroblast feeder layer

There has been a lot of debate regarding ethical issues surrounding human stem cell research, especially when it involves embryonic stem cells, because embryos need to be killed at a very early stage of their development to extract them. This approach raises the question of taking a human life and at the same time offers the prospect of providing researchers with the material that might one day be used as a treatment for many diseases. The gray area between the two doctrines has been the source of a big dilemma for the scientific world. Under the present legislation, the National Institutes of Health does not fund studies that involve human embryonic stem cell lines derived after August 2001, and that is where mouse stem cells come in.

They have played a pivotal role by being free of such controversies. Mouse stem cells have not only provided insight into some of the core principles regarding human development but have also shed light on novel ways to scrutinize the pathology of various medical disorders. They also offer hope for innovative modalities of treatment for diseases with significant morbidity and mortality despite currently available therapies.

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