Posted on behalf of David Cyranoski.
UPDATE: The first sentence of the final paragraph of this story was changed on 5 June to clarify a source.
The retraction of two controversial papers that promised a simple way to create embryonic-like stem cells seems to be imminent today after the lead author unexpectedly gave her full consent. Haruko Obokata, of the RIKEN Center for Developmental Biology in Kobe, Japan, had been the last obstacle to the retraction of both papers.
She agreed to retract the second of the two studies last week, but her agreement yesterday to retract the first one, which detailed the fundamental mechanism behind her claims, paves the way for the unravelling of what was heralded as one of the biggest scientific discoveries of the year.
All co-authors of the papers, which claimed to have created a new type of stem cell, known as stimulus-triggered activation of pluripotency (STAP) cells, now appear to have consented to the retraction. This leaves the papers’ fate in the hands of Nature, the journal that published the two studies in January. Requests for retractions with the unanimous support of the co-authors are usually authorized by the publisher. (Note: Nature’s news and comment team is editorially independent of its research editorial team.)
In the STAP studies, Obokata claimed that when she stressed cells by exposing them to acid or putting pressure on their membranes, they underwent a transformation to an embryonic-like cell. The STAP cells therefore shared the ability of embryonic stem cells and induced pluripotent stem (iPS) cells to convert into any of the body’s cell types, promising a huge advance to biomedical research and clinical applications.
But Obokata’s papers quickly came under fire after various manipulated and duplicated images were found in them. After an investigation into the allegations, RIKEN found Obokata guilty of misconduct on 1 April. Earlier this month, it rejected her appeal of the judgement, and asked her to retract both papers. In the meantime, at least a dozen other research groups reported that they were unable to replicate her findings.
As the controversy escalated, several co-authors publicly stated their desire for a retraction. But Obokata and a senior co-author on the papers, Charles Vacanti, of the Brigham and Women’s Hospital in Boston, Massachusetts, stood by the papers.
However, in an unexpected move on 28 May, Obokata consented to the retraction of the second paper, which describes how STAP cells can form placental cells as well as embryonic-like and iPS cells. But she remained resolutely behind the main paper, considering the second “just an extension”, her lawyer Hideo Miki said.
Then, out of the blue on 30 May, Vacanti sent a letter to Nature asking for a retraction of the first paper, according to a source in Japan who is close to the story and has seen Vacanti’s letter. This move may have broken Obokata’s resistance. On 3 June she signed an agreement to retract the first paper and handed it to RIKEN, a spokesperson confirmed. The spokesperson says that the authors are now in discussion with Nature with regard to retraction of both papers. Nature does not discuss retractions until final decisions are made.