Peer 2
Agreed - some of this is a little unclear. The apparent gel splice has already been commented. I'm guessing that the commenter is also suspicious about the odd-looking pixels in the images with…
Agreed - some of this is a little unclear. The apparent gel splice has already been commented. I'm guessing that the commenter is also suspicious about the odd-looking pixels in the images with…
It's a little unclear to me what you're trying to show. Can you explain a bit more?
those do in fact look similar upon close inspection. demands a response from nature and the authors IMHO
http://i.imgur.com/pdxuKOp.png
This comment on a previous paper from the group seems relevant to add some context to the discussion here:https://pubpeer.com/publications/D02B9A8C8A6D5C99B95E4FB3E1E13C#fb6333
Here's the DOI of the paper mentioned above. 10.1073/pnas.1100816108 VERY interesting indeed!Would very much like to hear an expert (or the authors') opinion of this possibility...
interesting, but haven't labs made iPS cells from clonal cells ie derived from a single cell?I don't know for surethis would argue against the MUSE cell idea, at least with regard to…
You are right. I'm encouraging people to do this. - Paul
Agreed that the more detail that is available, the more useful these reports will be. The response from the authors (and implicitly from the journal) if these reports continue to build up will be…
It would be great if you encouraged people to post actual data of negative attempts. A "yes" it worked or "did not work", hardly seems rigorous.
They conclude that their data indicate that strong stress reprograms mature lymphocytes into multipotent stem cells. As discussed on this site I also think their data are still not very solid for…
New article features some evidence of endogenous dedifferentiation in response to low pH et al offered up by developmental biologists including Gurdon...
I'm doing a new poll 2nd week into the STAP situation (you can vote again in this one) to judge the dynamic ranging opinions on the STAP paper and methods...
There are not that many cells in the human body, not even close! Please tell me how I misinterpreted that data. How do you interpret it? Again please tell me how I should understand it...
Hi Paul,I think crowd-sourcing replication attempts is a great idea. I could easily imagine that even if nobody could reproduce the work that not much of that effort would appear in public...
The "ultimate" proof that "STAP" cells generate embryos would be the presence of the Y chromosome in organs generated after injection of male cells into blastulas...
Hi,I've set up a new page for people to crowdsource their results from attempts to replicate the STAP stem cell method here. I blogged about it here: http://www...
"If the linked image is indeed Figure 1i"It is. You only need to tweak brightness and contrast settings to verify for yourself.
If the linked image is indeed Figure 1i, it does certainly look as if lane 3 was spliced in. I am under the impression that the correct procedure where two or more images are shown side by side is…
Vacanti has made revolutionary claims in the past that have not been easy for most labs to reproduce. These have concerned "spore-like" cells (or VSELs - Very Small Embryonic Like stem-cells), which…
Knoepfler turns skeptic:http://www.ipscell.com/2014/02/in-a-pickle-over-stap-stem-cells-top-5-reasons-for-skepticism/
As a naive viewer, I agree with Unreg that it is rather difficult to discern anything in the image. But maybe the nuclear/cytosolic localisation of the staining is obvious to experienced viewers...
please compare "correct" nuclear staining of KLF4 and ESRRB with that of Nanog or Oct4. Same magnification, same clusters of cells. Oct4 and Nanog staining is almost exclusively cytoplasmic!!!!!!!!!!!!
I think Fig 5d looks at clusters of cells (as would indicate the scale bar), so it's not possible to really discriminate nucleus vs cytoplasm at this magnification...
I agree that lane 3 was clearly spliced in. It is difficult to imagine how one can splicing in a lane in the middle of a blot by accident.It is disconcerting that the only blot that the authors…
Here is a false-colour image of Fig. 1i:http://imgur.com/1nBfKTrIt does seem as if somebody did not like the original "positive control" (according to the legend).
Knoepfler keeps on blogging, although there's maybe not that much substance at this stage (he mentions not having read the sister paper yet)...
In Fig 5d, antibody staining for OCT4 and NANOG - signal is cytoplasmic and should be NUCLEAR!! As it is the case for KLF4 and Esrrbeta, in the same figure...
I guess CD45+ cells here are not all T cells. They probably include B cells, NK, monocytes etc, all of which are in germline configuration. Since the CD45+ fraction also contains T cells, there is a…
This representation is actually quite common in some fields. For example, see Maus et al, Nat Biotech 2002, where expansion of T lymphocytes is plotted cumulatively as it is here...
Figure 1i lane 3...At higher magnification the background of that lane 3 is darker than the rest of the gel.Also vertical straight change background on each side...
I believe that our demonstration of pluripotent (capable of giving rise to healthy animals) cells in normal adults is of tremendous theoretical interest ...
From Paul Knoepfler's blog:http://www.ipscell.com/2014/01/review-of-obokata-stress-reprogramming-nature-papers/"...something akin to hitting the cells over the head with a sledgehammer of a pH 5...
@ Unreg ( February 1st, 2014 9:39pm UTC )I guess you didn't understand my comment. Let me try a slightly longer version. Imagine they put 10 cells in a culture flask and let them grow for 2 days, at…
here is the figure legend: Robust growth of STAP stem cells in maintenance culture. Similar results were obtained with eight independent lines...
Regarding the 10E60 scale: How do you know it's a "stupid error"? Did you actually try to understand the experiment, or did you just make a snap judgement? Yes, 10E60 is a big number...
I think you are missing the point of the paper entirely. Its message is that you CAN do it, and with what appears to be relative ease. I won't even begin to open the discussion of mutli-potent HSC...
In my view the main concern is that is all done with a gfp-oct4 reporter transgenic line. if for whatever reason that reporter became responsive to pH you will have Oct4 expression , and this may be…
Perhaps I don't know enough, but I am struggling to understand the results presented in figure 1i and how they can come about - any clarification would be great, because internet searches have failed…
It's difficult to see what you mean. Can you upload the brightness-adjusted image somewhere?