30 January 2014
Japanese researchers have created pluripotent stem cells (able to develop into multiple different specialised cell types) from blood cells by a new technique.
The stem cells were created by applying external stress – or as the researchers put it, ‘strong environmental cues’, in this instance exposure to low pH. STAP (stimulus-triggered acquisition of pluripotency) cells have only been created from mouse cells in this way, but efforts to replicate results in human cells are already underway. It is thought that the same mechanisms may operate in the body as a potential naturally regenerative response to physical stress and injury.
Induced pluripotent stem (iPS) cells were hailed as a scientific breakthrough – not least by offering a plausible and less ethically contentious alternative to human embryonic stem (ES) cells (derived directly or indirectly from foetal tissue) for stem cell research and applications in regenerative medicine. If human STAP cells can be successfully created they could offer an easier and more affordable alternative to iPS cells.
The STAP mouse cells have been reprogrammed and grown into multiple different cell types. Notably, they have already shown the capacity to give rise to placental tissue, which neither hES nor iPS cells have done, and the conversion rate from the initial blood cells to stem cells is apparently significantly higher than that for iPS cells, at 7-8% and 1% respectively.
Lead researcher Dr Haruko Obokata from the Riken Centre for Developmental Biology in Japan commented: "It's exciting to think about the new possibilities these findings offer us, not only in regenerative medicine, but cancer as well". Dr Obokata had to amass a large body of evidence that the STAP cells were genuinely reprogrammed adult cells before her work was accepted for publication.
Experts have hailed the new technique with enthusiasm, describing it as ‘revolutionary’, ‘remarkable’ and ‘a game-changer’.