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Uses - Medicine

Stem Cells

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Stem cells are young cells found in embryos that have the capacity to develop into various types of

Stem Cells
tissue, such as brain, heart, stomach, etc. These cells can be used to develop organs that can repair or replace damaged human organs. Using tissue created by this method is safer, not to mention much more plentiful, than using donated tissue. This is useful to replace cells that do not grow back, such as brain cells. Why is there such a hype about this? In the process of initially taking a stem cell from a human embryo, the embryo is destroyed. Some people contend this amounts to murder. Furthermore, this technology could be abused to clone a human. To see what the current policy on stem cells is, click here.

There are several ways stem cells can be obtained. Different stem cells are easier to develop into certain tissues.

  Embryonic From the Adult Body
 

In vitro fertilization - After eggs are fertilized in a laboratory and allowed to grow in a blastocyst of a few hundred cells, the inner mass is removed, which are the stem cells. This is what people most commonly refer to, and has had the most success, especially in mice.

 

 

Adult Stem Cells - These are naturally present in the body as a part of its repair process. They may only turn into limited types of cells, and so far no one has succeeded in using them to treat diseases

Fetal cells - During a woman's pregnancy, a small number of cells from the fetus enter the bloodstream. These cells remain in the bloodstream after pregnancy and travel to damaged tissues or organs, where they divide into the appropriate cell. This is still a relatively new development.

Controversy
Controversy occurs in the heated stem cell research debate. In the process of harvesting stem cells, the embryo is destroyed. Some say it amounts to murder; others claim the embryo is merely a collection of cells, not a human
No widespread objections have been made to using adult cells, as no embryos are destroyed. The problem is that these are more limited in function than embryonic stem cells.

Currently, scientists are trying to find a way to effectively make the stem cells transform into the desired type of cell. They are still conducting experiments on animals, and have not entirely cured a disease yet.

Sources

  • Kolata, Gina. "Promise, in Search of Results." New York Times 24 Aug. 2004: F1+. An update on stem      cell research.

Images

  • http://www.news.wisc.edu/packages/stemcells/3327.html