Touching Lives - June 2006
Stem cells — what exactly are they?
You may have read on page 13 about a new Action Medical Research project that is looking at the potential of using stem cells to help brain damaged babies. Stem cell research is often making headlines, but not everyone understands the subject.
Stem cells begin when the sperm and the egg unite and form a single cell. This cell contains all the information required to build every part of an animal, or human in our case, from the root, from which an eyelash grows, to a kidney, to the whole nervous system, including the brain.
This first cell is called ‘totipotent’, because its potential is total. It gives rise to all the different types of cells in the body. It divides time and time again and after even quite a small number of divisions the cells are no longer all the same. Most will have started on the route to become specific parts, like organs, but a few remain versatile.
These versatile cells, which are called stem cells, come in different varieties, but they all share the ability to go on dividing, producing more of their own kind. What is more, they can be grown indefinitely outside the body as cell lines, where every cell has identical properties. The varieties differ in how versatile they remain.
^Even in adults there are some, but very very few, stem cells of limited versatility. In a foetus there are many more and they are plentiful in the blood stream^, from where they can be isolated and then grown in the laboratory so as to multiply to a substantial number. So, why are stem cells so exciting? Well, inside every one is the blue-print for many kinds of specialised cells. It is possible that they can be used to colonise damaged areas and make new tissue, which is just right for a particular location. And if the stem cells come from the individual who has to be “repaired”, the problem of rejecting foreign tissue does not arise. Some diseases that stem cells could be used to treat include stroke, heart disease, diabetes, cancer, Alzheimer’s and Parkinson’s.
The use of stem cells in medical treatment is a very new subject and Action Medical Research is considering in which areas we should support this very exciting prospect.