Different kinds of stem cell
When body tissues are destroyed by age, disease or injury, stem cells generate fresh new cells. By learning to control how stem cells are transformed into other kinds of cell, scientists hope to be able to cultivate different tissues outside the body for transplantation into the body as a treatment for disease.
Three different kinds of stem cell
Embryonic stem cells
Embryonic stem cells can divide an unlimited number of times, and have the potential to develop into all the bodys tissue and cell types. They are only found in the early embryo.
Adult stem cells
These stem cells exist in the adult body and can generate only a limited number of cell types. For example, the bone marrow contains blood stem cells, which form red and white blood cells. Connective tissue stem cells, which are also found in the bone marrow, can form bone, cartilage, muscles and fat.
In recent years, scientists have learnt how to manipulate stem cells in the laboratory so that they take on the same properties as embryonic stem cells. It is now hoped that these so-called iPS cells (induced pluripotent stem cells) will open up new opportunities for stem cell therapy.
Text: Ola Danielsson. Published in Medical Science, no. 2/2009.