‘New stem cell source’ discovered

US scientists say they have discovered a new source of stem cells that could one day repair damaged human organs.

Researchers successfully extracted the cells from the fluid that fills the womb in pregnancy and then grew them in lab experiments. The types of potentially useful stem cells have so far been derived from specially grown human embryos.But this has created ethical concerns because the embryos are destroyed in the process.Opponents say this is tantamount to cannibalism.Supporters say stem cells offer real hope in treating illnesses like diabetes, Parkinson’s and Alzheimer’s.Writing in Nature Biotechnology, the scientists said it should be possible to harness the cells’ ability to grow into different tissue to treat disease.However, UK experts had doubts about the feasibility of the technique.They said gathering amniotic fluid from large numbers of women might be difficult.Amniotic fluid contains a large number of cells, many of which come from the developing foetus.The team from Wake Forest University School of Medicine, in North Carolina, extracted these from fluid samples taken as part of unrelated diagnostic tests during pregnancy, then encouraged them to grow in the laboratory.They found that they had the potential to turn into a wide variety of different cells – the hallmark of potentially useful stem cells.They then transplanted them into mice, and carried out further tests to look at how they performed in a living creature.Again, the results were encouraging, with the stem cells spreading and starting to produce key body chemicals in both brain and liver.Bone stem cells introduced onto an artificial ‘scaffold’ then implanted into mice also appeared to behave in a similar way to normal bone cells, forming bone even months later.The conclusion of the researchers was that the amniotic cells were ‘pluripotent’ – capable of becoming many different cell types, and that they held the potential for treatment – particularly on the child from whose mother they were taken, for whom they are an exact tissue match.Dr Paolo De Coppi, now of Great Ormond Street Hospital, who worked on the study, said the amniotic stem cells were similar to, but not identical to, embryonic stem cells.BBCThe types of potentially useful stem cells have so far been derived from specially grown human embryos.But this has created ethical concerns because the embryos are destroyed in the process.Opponents say this is tantamount to cannibalism.Supporters say stem cells offer real hope in treating illnesses like diabetes, Parkinson’s and Alzheimer’s.Writing in Nature Biotechnology, the scientists said it should be possible to harness the cells’ ability to grow into different tissue to treat disease.However, UK experts had doubts about the feasibility of the technique.They said gathering amniotic fluid from large numbers of women might be difficult.Amniotic fluid contains a large number of cells, many of which come from the developing foetus.The team from Wake Forest University School of Medicine, in North Carolina, extracted these from fluid samples taken as part of unrelated diagnostic tests during pregnancy, then encouraged them to grow in the laboratory.They found that they had the potential to turn into a wide variety of different cells – the hallmark of potentially useful stem cells.They then transplanted them into mice, and carried out further tests to look at how they performed in a living creature.Again, the results were encouraging, with the stem cells spreading and starting to produce key body chemicals in both brain and liver.Bone stem cells introduced onto an artificial ‘scaffold’ then implanted into mice also appeared to behave in a similar way to normal bone cells, forming bone even months later.The conclusion of the researchers was that the amniotic cells were ‘pluripotent’ – capable of becoming many different cell types, and that they held the potential for treatment – particularly on the child from whose mother they were taken, for whom they are an exact tissue match.Dr Paolo De Coppi, now of Great Ormond Street Hospital, who worked on the study, said the amniotic stem cells were similar to, but not identical to, embryonic stem cells.BBC