The Yomiuri Shimbun University of Yamanashi Prof. Teruhiko Wakayama, who coauthored two articles about stimulus-triggered acquisition of pluripotency (STAP) cells with RIKEN researcher Haruko Obokata and others, has called on all the researchers involved to withdraw the articles, saying there are many questionable points.
The two articles on STAP cells were carried in the Jan. 30 edition of the British journal Nature. While there are 14 coauthors for the articles, Wakayama is the first to officially urge the withdrawal of the articles.
In January, an international research team led by Obokata announced the creation of STAP cells, saying that by applying a strong stimulus to mice cells, such as dipping them in an acid solution, these cells could return to the undifferentiated state of a fertilized egg. STAP cells are described as a third kind of pluripotent cells, following two similar types—embryonic stem (ES) cells and induced pluripotent stem (iPS) cells.
However, critics have pointed out the STAP cell articles contain many problems, including the alleged reuse of identical images and suspected plagiarism.
At a press conference held at the university on Monday, Wakayama said images that show the pluripotency of STAP cells look almost identical to those used in Obokata’s doctoral thesis, which he saw on the Internet. Referring to that and other points, Wakayama said, “These raise suspicions over the credibility of important elements involving the foundation of STAP cells.”
Obokata’s doctoral thesis was about pluripotent stem cells that exist in the human body. Wakayama said he could not judge whether STAP cells used in experiments were real or not after he saw the images used in the doctoral thesis.
“I’m no longer sure that the articles are correct,” Wakayama said at the press conference.
He also expressed his intention to have a third-party research institute examine STAP cells kept at his laboratory.
Wakayama was in charge of experiments using mice to confirm the pluripotency of STAP cells created by Obokata.
Meanwhile, a RIKEN spokesperson said: “We’ve contacted other coauthors belonging to RIKEN. We’d like to consider how to deal with this issue.
“At present, we don’t think the credibility over the essential parts of STAP cells is shaken.”