Q&A - Stem cells could offer treatment for a myriad of diseases

Q.What are stem cells?

A. There are 220 cell types in the body and all of these have a particular function such as nerve cells or pancreatic cells.

Stem cells are different however as they are at an earlier stage in cell development and this means they can make more cells and transform into different cell types such as a skin stem cell can make all the different types of skin cells.

Q. And there are two types?

A.Yes. There are two types of stem cells: embryonic stem cells and adult stem cells. Embryonic stem cells can generate all cells of the human body. Adult stem calls generate a more limited number of human cell types.

Q.Why are stem cells so important?

A.For many years, adult stem cells have been used to treat rare blood and certain cancers.

However, adult stem cells can’t generate all cell types. For example, scientists say there doesn’t appear to be an adult stem cell that can make insulin- secreting cells of the pancreas. Embryonic stem cells can, however, as they can generate all cell types and the aim of scientists is to use these embryonic cells to generate healthy tissue to replace cells compromised by disease. This means that embryonic cells are more scientifically useful.

Q. And it’s also embryonic cells that are the more controversial, right?

A.The use of embryonic stem cells is controversial here and in other countries as certain groups believe it is morally wrong to experiment on an embryo that could become a human. Embryonic stem cells are taken from embryos left over after assisted fertility treatments. According to the Irish Stem Cell Foundation, if they weren’t used for research into human disease, they would be discarded as medical waste. Embryos are not created purely for research purposes they say.

Q. Why are they so useful?

A. Among the conditions which scientists believe may eventually be treated by stem cell therapy are Parkinson’s disease, Alzheimer’s disease, heart disease, stroke, arthritis, diabetes, burns and spinal cord damage. Early trials are under way for treating forms of blindness. It is also hoped we can learn from embryonic stem cells how early body tissues develops and more about the pathway of diseases. This will enable us to make better and more effective drugs.