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Name: Gloria H.
Status: Other
Age: Old
Location: N/A
Country: N/A
Date: August 2004

Can you please explain (in very simple terms) what a stem cell is does?

Basically, stem cells are cells that are not assigned a functional job in an organism as yet. Stem cells can use them to repair or replace functional (working if you like) cells that are damaged or destroyed. Many tissues (groups of cells working together to get a job done) are too complex to reproduce if the need arises, so we find that in some cases, these tissues have stem cells for this purpose.

Fetal organisms have a great deal of these types of cells since this stage of an organism's development does not have many functional cells in this early stage of development.

Stems cells are extremely important since we now understand how to get them to change into any type of cell that is needed. This process is probably the most important discovery in medicine since vaccines. For stem cells will be able to used to cure many thought incurable diseases by making them become correctly functioning cells of any type to replace diseased or nonfunctional cells that cause disease, especially those that become more evident with old age.

I hope this helps.

Steve Sample

Stem cells are cells found in an early stage of embryonic development. These cells have the potential of developing into any or all types of cells which are eventually found in a fully formed human fetus. These cells are by definition undifferentiated and pluripotent, i.e. capable of developing into any type of diferentiated cell. There are stem cells found in bone marrow, for example, and they are capable of developing into a variety of blood cells (platelets, red blood cells, or white blood cells) but they are less capable of developing into other types of cells.

Regards. Ron Baker. Ph.D.

Our bodies must make millions of cells each day to replace the cells that die. We make millions of red blood cells and white blood cells each day. I will use blood cells for an example since most of what we know about stem cells comes from research on blood. Stem cells are in our bone marrow. They are very primitive cells in that they have not matured into any specific type of cell that functions in a specific way. Now there are many different kinds of white blood cells: macrophages, eosinophiles, basophiles etc., each of which performs a very specific job. All of these cells are derived from a common stem cell. If you transplant this sort of cell into a person who because of a disease or condition cannot produce these white blood cells, the person can regain the ability to produce the white blood cells again.

In a developing fetus and even some of the tissues associated with the fetus have numerous stem cells that can produce all the different tissues of an adult body. The hope is we can use some of the stem cells to replace tissues of any human in certain cases where new tissue is needed...a possible cure for numerous diseases from diabetes, and leukemia to Parkinson's. It is NOT necessary to derive stem cells directly from a human fetus and or kill a developing fetus to obtain stem cells.


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