A criminal investigation now seems likely in the STAP stem-cell research debacle after a former Riken researcher filed a criminal complaint against disgraced scientist Haruko Obokata, alleging she stole samples of embryonic stem cells before reporting that she had created her version of stem cells with a novel technique.
Toshihisa Ishikawa, a former senior researcher at the government-affiliated scientific research organization, submitted the complaint to police in Hyogo Prefecture, where Obokata as a Riken researcher conducted her stem-cell research.
The work secured publication in the prestigious science journal Nature and was widely hailed as groundbreaking before allegations of fabrication emerged.
Ishikawa was not immediately available for comment Tuesday, but press reports have carried his account of what he believes happened.
“I am convinced the ES cells Ms. Haruko Obokata used to fabricate her STAP cells were those she stole from the research room of Mr. Teruhiko Wakayama,” the latest issue of the gossip weekly Friday quoted Ishikawa as saying. “I’m going to file a criminal complaint against her alleging that she stole the ES cells, because otherwise confidence in Japan’s science will be entirely lost.”
The prefectural police have yet to decide whether to accept Ishikawa’s complaint.
A Riken spokesman said Ishikawa was acting in his private capacity in submitting the complaint, but that the institute would cooperate if police ask it to.
Noting that the details of the complaint are still not known and that the police may ultimately reject it, a lawyer representing Obokata nevertheless denied that she stole samples of cells.
“Just to be sure, there is no fact that Ms. Obokata stole ES cells, nor was she motivated to do so,” lawyer Hideo Miki said in a statement Monday. “From what I learned through hearsay, the complaint is poorly put together, and it significantly contradicts the facts. . . . I hope to take appropriate action as necessary.”
Ishikawa, who retired from the famed institute last March, alleges the Obokata stole ES cells that were created and stored at the Riken laboratory of Teruhiko Wakayama, which she belonged to, some time after April 2011.
Wakayama, now a Yamanashi University professor, was a co-author of the discredited papers that claimed to have discovered a new and simpler way to produce pluripotent stem cells, which are capable of developing into any type of tissue. The cells’ reprogramming process is known as stimulus-triggered acquisition of pluripotency, or STAP.
Obokata was the lead author of both papers.
Initially hailed as ground-breaking research after it appeared in Nature in early 2014, the papers were eventually retracted amid allegations of fraud.
In late December, Riken’s investigative panel judged that Obokata’s STAP cells were in fact embryonic stem cells. Obokata did not appeal the ruling.
The panel reported that a container labeled “ES cells” was found in her research room but stopped short of determining whether its contents had been mixed into her samples, or if it had, whether by accident or intentionally.
Obokata has denied the possibility of either.