Cord Blood Stem Cells Information

What are embryonic stem cells & why not derive stem cells from adults?

Public Comments

1. Embryonic stem cells have the capacity to form into any type of organ or other cell. Adult cells are already formed and can't be changed - you can't make a heart cell suddenly become a liver cell.
2. the stem cells are the simplest building blocks of humans. but adults dont have them because they have already converted the stem cells into organs etc. the stem cell can turn into anything the body is made of. embryos have the only viable source. morality aside.
3. With some of the newer technology that reprograms adult skin cells into viable "general" stem cells there's really no need to derive stem cells from embryos anymore: http://www.nytimes.com/2007/11/21/washington/21bush.html?hp
4. The issue is the "totipotency" of the ES cells. ES cells can become *any* cell type found in the adult body: they are "totipotent". Adult stem cells, OTOH, are "multipotent": they can become several different cell types. For example, bone marrow mesenchymal stem cells can become muscle, bone, cartilage, and fat cells. But not nerves, or intestine epithelia, etc. It is possible, with advancing technology, that we will be able to "de-differentiate" some adult stem cells, and increase the number of cell types that have the potential to become. But currently, true totipotency can only be acheived with ES cells.