Reports in Japan suggest Haruko Obokata, of the RIKEN Center for Developmental Biology in Kobe, has agreed to retract one of two controversial papers in which she claimed to have created a new type of stem cell, known as stimulus-triggered activation of pluripotency (STAP) cells. The development means that the path may now be clear for the full retraction of one of the biggest science papers of the year.
The studies, published in Nature in January, promised a surprisingly straightforward path to creating pluripotent stem cells, which can turn into any cell in the body, by stressing bodily cells with acid or physical pressure. Such an easy process for creating pluripotent stem cells would be a huge boon for biomedical research and potentially useful for clinical transplants. (Note: Nature’s news and comment team is editorially independent of its research editorial team.)
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 judgment, 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.
Several of Obokata’s co-authors have stated their desire to retract the papers. But Obokata has adamantly stood by her research, insisting that the STAP phenomenon is real and defying RIKEN’s request to retract.
Today, however, all of Japan’s major newspapers reported that Obokata had finally agreed to retract the second of the two papers. The Asahi Shimbun quotes Obokata’s lawyer as saying Obokata contacted Yoshiki Sasai, a co-author and colleague at the Center for Developmental Biology who has expressed his willingness to retract, and said, “I will not oppose the retraction.” The Mainichi Shimbun quotes lawyer Hideo Miki as calling it a “passive agreement“.
Ironically, the paper that Obokata has agreed to retract was not the one found by RIKEN to contain manipulation. Obokata still stands by that paper, which establishes the basic technology for creating STAP cells.
In the paper that Obokata has agreed to retract, she and her team claimed that STAP cells cannot only form pluripotent stem cells but can also form placental cell lines – something other forms of pluripotent stem cells, like induced pluripotent stem cells and embryonic stem cells, cannot do.
“To Obokata, the paper that made clear the existence of STAP is the important one. The other [which she has agreed to retract] is nothing more than an extension,” says Miki.
Customarily, all authors of a paper must agree to a request for its retraction, although retractions without the assent of all authors are possible. A source at RIKEN told Nature‘s news team that a retraction request was sent on 26 May, and that all the co-authors either stated that they agreed to it or did not oppose it. The other senior co-author who has steadfastly refused to retract the papers, Charles Vacanti of Brigham and Women’s Hospital in Boston, Massachusetts, would not comment on the reports of a retraction request. “There is no updated statement from Dr Vacanti,” a media relations officer wrote in an e-mail.
A spokesperson for Nature could not verify the status of the request. “Nature does not comment on corrections or retractions that may or may not be under consideration, nor does it comment on correspondence with authors, which is confidential,” she said. “We are currently conducting our own evaluation and we hope that we are close to reaching a conclusion and taking action. We take all issues related to any Nature paper very seriously and look into them in detail. We cannot comment further at this time.”