Stem cells are a normal part of all tissues in the body. They are characterised by their ability to renew themselves and to convert into a range of specialized cell types able to perform specific functions. There are many types of stem cells in the adult body. Each of these are limited to the types of cells that they can create. For example, in bone marrow there are stem cells that can make all of the cells in blood including white blood cells, red blood cells and platelets.
Embryonic stem cells are the most potent of the stem cells. They can develop into any one of the over 200 cell types of the adult body.
Source: International MND research update -September 2009, Dr Justin Yerbury for MNDRIA