Studies in a number of research institutes have discovered that reprogrammed skin cells which function similarly to stem cells derived from human embryos can be useful in easing the symptoms of Parkinson’s disease. The created cells were transplanted into the brains of rats which had been altered to resemble the neurodegenerative Parkinson’s disease, with positive results. The discovery avoids the controversial issue of using embryonic stem cells for cell transplants, because the human embryos they are sourced from are normally destroyed.
The reprogrammed skin cells, referred to as induced pluripotent stem cells or IPSCs, are synthesized by the transfection of the genes OCT4, SOX2, NANOG and LIN28 into human somatic cells, essentially transforming them into the highly malleable stem cells. The created cells have similar morphological and biochemical properties to naturally created embryonic stem cells. These cells are then integrated into the neural system of rats to replace the brain cells that produce dopamine, a chemical which carries neural messages. The preliminary results of these tests are positive, with 100% of the test subjects showing marked improvement after treatment with the IPSCs.
However there will need to be further studies and improvements on the technique before it can be tested on humans. Currently the required genes are transported into somatic cells using retroviruses, which have the potential to cause cancer. Also, the synthesized IPSCs can differentiate into tissues other than those under study. This setback has been combated though, with the use of fluorescent proteins to mark the brain cells which produce dopamine.
Fox, M 2008, ‘Stem cells from skin treat brain disease in rats’, Web Article, viewed 8 April 2008, http://www.reuters.com/article/topNews/idUSN0719560620080407?feedType=RSS&feedName=topNews.
Baker, M 2007, ‘Adult cells reprogrammed to pluripotency, without tumours’, Web Article, viewed 8 April 2008, http://www.nature.com/stemcells/2007/0712/071206/full/stemcells.2007.124.html