Amniotic fluid cells instead of embryonic
British researchers led by Dr. Pascal Guillot and Dr. Paolo De Coppi managed to turn amniotic fluid stem cells into cells similar in properties to embryonic stem cells without introducing additional genes into their DNA.
Amniotic fluid surrounds and protects the fetus developing in the uterus. A small amount of it can be obtained with the help of amniocentesis – a puncture of a pregnant woman's abdomen with a special needle. Amniotic fluid contains fetal cells, so amniocentesis is used in certain cases to diagnose genetic diseases. This procedure is quite safe: the risk of miscarriage induced by it is 1:100.
Scientists isolated cells from amniotic fluid obtained as a result of amniocentesis performed on women in the third trimester of pregnancy for medical reasons. The differentiation potential inherent in these cells is much lower than the ability to differentiate the cells of the embryo itself. However, as a result of cultivation on a gel-like mixture of proteins in a medium containing valproic acid, the cells returned to a more primitive state. The versatile testing confirmed their close similarity with pluripotent (capable of giving rise to all types of cells of the body) embryonic stem cells.
Even after cultivation for a certain time, the reprogrammed cells did not lose the ability to transform into functional cells of various types, including hepatocytes, osteocytes and neurons. They also demonstrated the ability to maintain pluripotency after cryofreezing and subsequent defrosting.
The data obtained indicate that amniotic fluid cells can be isolated, reprogrammed and stored in stem cell banks for subsequent use in cell therapy of a wide range of diseases. According to the results of earlier studies, a bank containing 150 donor cells is able to meet the need for compatible donors for 38% of the population.
The use of these cells also eliminates ethical problems associated with the clinical use of embryonic stem cells, the production of which requires the destruction of human embryos. Until now, the only alternative to embryonic cells has been induced pluripotent stem cells (iPSCs) derived from adult cells. However, in this case, the reprogramming process is ineffective and requires the use of foreign, including viral, genetic material. Therefore, amniotic fluid cells, which require only valproic acid for reprogramming, look like a very promising candidate for clinical use.
Article by Moschidou et al. Valproic Acid Confers Functional Pluripotency to Human Amniotic Fluid Stem Cells in a Transgene-free Approach published in the journal Molecular Therapy.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Imperial College London:
Amniotic fluid yields alternatives to embryonic stem cells.
06.07.2012