|Scientists have discovered a way to make stem cells from skin cells
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Scientists have reprogrammed human skin cells to become cells that look and act just like embryonic stem cells. Stem cells are a special type of versatile cell that scientists think may be able to cure many human heath problems in the future.
These special reprogrammed cells, called induced pluripotent stem (iPS) cells, have the potential to become any one of 220 types of cell found in the human body.
The race to make the cells started in June 2006, when iPS cells were first created from mouse tail skin cells. The competition has ended in a tie, with two different groups publishing their results this month.
The two groups have used slightly different genes to achieve the same outcome.
Dr Shinya Yamanaka and his team inserted four genes into facial skin cells from a 34 year old woman and also into connective tissue cells from a 69 year old man. This reprogrammed them as iPS cells. The genes they used were called Oct3/4, Sox2, Klf4 and c-Myc.
Shinya’s team made cells that are not completely identical to embryonic stem cells, but they can still use them to make brain and heart tissue. The heart tissue started beating after just 12 days in the laboratory.
Professor James Thomson and his colleagues used four genes too. They chose two of the same genes – Oct3 and Sox2, and two different genes – Nanog and Lin28. The cells they transformed were from the foreskin of a newborn boy and the skin of a foetus.
“The induced cells do all the things embryonic stem cells do – it’s going to completely change the field,” says James.
Both techniques use special viruses called retroviruses to insert the genes. These have the potential to cause tumours in tissues grown from iPS cells, which prevents their use in patient trials.
The next step for researchers is to learn how to reprogram the cells without the use of a potentially dangerous retrovirus. They will attempt to turn existing copies of the genes on, rather than inserting new copies.
“These cells should be extremely useful in understanding disease mechanisms and screening effective and safe drugs,” says Shinya.
Many stem cell techniques have involved the destruction of an embryo to personalise treatments. Some people think this is the destruction of a potential human, a belief in conflict with some religious and moral views held in society.
This breakthrough means researchers may no longer be dependent on cells from human embryos. This will help address some of these ethical and political issues.
Let’s hope this new research allows medical researchers to be able to put stem cells to good use. Stem cells have the potential to treat a wide range of diseases including cancer, Parkinson’s disease, spinal cord injuries, and muscle damage.