OSAKA - Embattled cell biologist Haruko Obokata can neither confirm nor reject a recent claim by the government-backed Riken institute that there are further inaccuracies in images in one of the research papers she co-wrote on stem cell development, her lawyer said Thursday.
Hideo Miki quoted her saying that she “was not in charge of the image” in question and thus could not identify whether it is accurate.
Miki told reporters in Osaka that Obokata only learned about the latest allegation through news reports, and he criticized the institute for releasing information that was not included in its final report on previous allegations leveled at the papers.
Obokata is accused of falsifying parts of purportedly trailblazing work on what she called stimulus-triggered acquisition of pluripotency cells, or STAP cells.
She was reacting to remarks made by officials of her institute on Wednesday.
The officials said images of two mice, presented as each showing the outcome of a different experiment related to STAP cells, were in fact photographs of the same mouse.
They said at least one of Obokata’s fellow authors has confirmed this. Riken learned of the inaccurate images through a tip, the officials said.
The images in question purported to show two types of “chimeric” mice — one grown from STAP cell origins and the other from embryonic stem cells — and the difference between the two types of cells regarding their versatility, or ability to develop into any type of tissue.
An image purportedly showing an embryonic mouse created with STAP cells also shows a placenta, giving some credence to the researchers’ claim that their STAP cells are more versatile, because embryonic stem cells are known to lack the ability to develop into certain parts of a placenta.
Some of the authors plan to consult with the British journal Nature, which published the papers in its late January edition, over what to do about the inaccurate images.
In the Nature papers, Obokata and her co-authors claimed that STAP cells can be produced simply by subjecting somatic cells from a mouse to stress — in this case, a weak acid.