Perspectives on high-profile stem cell retraction in the making from Kyoto University

IPS cell paper retraction requested
Screenshot from NHK video on IPS cell paper problems

A researcher working at Kyoto University has reportedly engaged in misconduct leading to an institutional request for retraction of a paper from the journal Stem Cell Reports.

The paper in question appears to have rather large-scale problems:

“Kohei Yamamizu, a specially appointed assistant professor at the university’s Center for iPS Cell Research and Application, falsified all six main figures in the paper that claimed he had succeeded in generating a brain structure in vitro using iPS cells, according to Kyoto University.”

The Center for iPS Cell Research and Application, also known as CiRA, is a flagship induced pluripotent stem (IPS) cell institute and is run by IPS cell discoverer and Nobel Laureate Shinya Yamanaka.

Yamanaka, not involved in the research in question, nonetheless was quoted about this stem cell retraction and understandably down about it. I would be too in that kind of situation. I don’t see that Yamanaka could have done anything to prevent this though so it’s clearly not his fault in any way:

“I am very regretful for not being able to prevent the dishonesty,” said Yamanaka, professor at Kyoto University who won the Nobel Prize in medicine in 2012 for discovering induced pluripotent stem cells, or iPS cells.

“I will take (the incident) seriously and provide education necessary to prevent similar misconduct from happening again,” Yamanaka told a press conference.”

The paper in question seems to be a 2017 article entitled, “In Vitro Modeling of Blood-Brain Barrier with Human iPSC-Derived Endothelial Cells, Pericytes, Neurons, and Astrocytes via Notch Signaling” and the alleged misconduct was from first author Kohei Yamamizu. The PI on the paper is Jun K. Yamashita. I noticed that another recent stem cell paper on which Yamamizu and Yamashita are authors has a correction.

It remains unclear how the alleged misconduct was detected. A newer NHK report (apparently this story also made the nightly news in Japan; see screenshot above from news video) also weighs in and indicates some data was fabricated:

“The university set up a panel to investigate the credibility of the paper after doubts were raised about it.

The investigation found 11 images were fabricated or altered to back up the paper’s findings.

The university determined that Yamamizu, who had analyzed the data and made the illustrations, was responsible for the wrongdoing.

He has reportedly admitted to the falsifications, saying that he wanted to make the paper more visually appealing.”

Even an ugly or relatively plain-looking paper is better than a flashy one if the ugly one is more accurate and the data rock solid. Sometimes I think certain reviewers unrealistically expect biology to be so simple as to produce perfect looking data and figures. Biology is most often not that straightforward. This is of course no excuse for misconduct.

The stem cell field has had quite a few retractions over the years, but I was thinking that in 2017 there hadn’t been many high-profile ones compared to past years. At one point I compared stem cell retractions to those in the cancer field (which do you think had more?) Perhaps the most well known stem cell retractions of all are those of the two Nature papers on STAP cells, which were critically reviewed early on here at The Niche.

We’ll see what fate awaits this paper and how this unfortunate situation plays out. I don’t see it as a setback for the IPS cell field at all, but still should be taken seriously for what it is.

4 thoughts on “Perspectives on high-profile stem cell retraction in the making from Kyoto University”

  1. That is amazing. What other academic institution requires submission of lab notes and data? Companies require bound notebooks and co-signatures for each page, but no academic group that I know of does.

  2. Malvin Leonardo Pardi

    According to Mainichi Shinbun (, apparently CiRA requires their researchers to submit lab notes periodically (once in three months) and made original data submission before publication compulsory. However, it seems that the data are not checked thoroughly enough and lab note submission does not reach 100 percent.

    Hopefully CiRA revamps their data verification system.

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