Usually people think that people mature cells in their natural environment did not go the ability to differentiate into stem cells, but Jayara Rajagopal professor at Harvard University, recently found a surprise: in the case under pressure or injury mammals ordinary mature cells can go differentiate into totipotent stem cells.
Three strong research published in this weeks issue of Nature above. From Japan Riken Institute and Harvard scholars reported that newborn mouse spleen cells in the "acid bath" (coffee weak acid is added in a dish) pressure dedifferentiation, forming stem cells.
But "acid bath" experiment recently suffered an unprecedented crisis of confidence. Japan is no way to duplicate this experiment out. Riken Institute, the investigation team found that the proposed method of the authors, there are two Haruko Obokata fraud, there is a completely fabricated data in the test. This greatly damage the effectiveness of the article, may even result in the article being recalled.
But the other three similar experiments in mammalian stomach, bronchus, kidney cells, carried out by different research teams, respectively - and not much criticism. Two of these are still Faculty of 1000 is widely discussed.
These three studies are of great significance and it is full of imagination, development immunologist at the University of Pennsylvania Avinash Bhandoola commented. University of Pittsburgh Cancer researcher Michael Lotze said in an interview: "The potential of these three studies are extraordinary, they reveal the plasticity of the cells in the face of pressure from a deeper level, while providing a great inspiration for the human understanding cancer. "
Although long ago mature cells have been shown to have formed iPSCs differentiation potential of stem cells in vitro engineered by the way. But never test can confirm, mature mammalian cells in their natural environment can go differentiate into stem cells. At least three experiments have demonstrated above, under certain circumstances, all of this is possible.
The three experiments and "acid bath" experiments are in fact many critical differences. First, pressure-derived cells are different: these experiments did not use acidic substances. Secondly, the "acid bath" experiments in vitro (in vitro) to complete, in the implanted cells while the damage to the reporter gene GFP cells, as long as the purpose of the cell is a symbolic expression of the differentiation potential of Oct4 gene, GFP will light cells. While the other three experiments in vivo (in vivo) carried out, scientists damaged cells after lineage tracking through (Lineage tracing techniques) to observe to the differentiation of mature cells. (Of which two are to observe the differentiation of mature cells damage the surrounding cells, as well as an already damaged cells tracked and traced the circumstances surrounding the cells).
Third, the other three experiments just reported to the epithelial cell differentiation. The "acid bath" experiment claiming different organizations have found the phenomenon of dedifferentiation.
Finally, in the other three experiments, the cells did not like the "acid bath" experiment claims to be the embryo of. Become a mature cell reversal intermediate form similar malleable stem cells that looks like the face of a natural response to epithelial tissue stem cell damage made.
There are also a number of other differences, but the four most critical point of difference.
Two experimental groups study: Stem cell damage caused by epithelial dedifferentiation
Dedifferentiation of committed epithelial cells into stem cells in vivo
Nature 503, 218–223 (14 November 2013) doi:10.1038/nature12777
Differentiated Troy+ chief cells act as reserve stem cells to generate all lineages of the stomach epithelium.
Cell. 2013 Oct 10;155(2):357-68. doi: 10.1016/j.cell.2013.09.008.
A third study of experimental groups: Responding kidney epithelial cell injury dedifferentiation
Differentiated kidney epithelial cells repair injured proximal tubule.
Proc Natl Acad Sci U S A. 2014 Jan 28;111(4):1527-32. doi: 10.1073/pnas.1310653110. Epub 2013 Oct 14.Original Paper