STAP cells or Stimulus-Triggered Acquisition of Pluripotency cells were allegedly derived from adult mouse cells by subjecting those adult cells to a variety of environmental stresses. Even though the derivation of STAP cells was not terribly efficient, the ability to make pluripotent stem cells without viruses or the introduction of new genes seemed to be a godsend for stem cell scientists. Unfortunately, further testing and inquiries into STAP cells has revealed multiple problems and several labs have been completely unable to recapitulate the results of the researchers who reported the derivation of STAP cells. These problems have led many scientists to question the factuality of STAP cell derivation.
STAP cells took another hit this week when genetic tests of STAP cells indicated that those cells do not match the mice from which they were allegedly derived, according to a report from Nature News Blog.
The derivation of STAP cells were initially reported by Haruko Obokata from the RIKEN center and her colleagues. Given the remarkable nature of the claims in those papers, many scientists were skeptical and moved to test the protocols utilized by Obokata and others in those paper to make STAP cells from adult mouse cells. Unfortunately, these independent tests universally flopped, and an internal investigation by the Riken Center came to the conclusion that Dr. Obokata was guilty of research misconduct, which she has denied.
Teruhiko Wakayama, a scientist from Yamanashi University and one of the co-authors on the STAP papers, subjected some of the cell lines that he derived using the STAP approach back in March to a battery of genetic tests. He was dismayed to discover that some of these cell lines did not match the adult mice from which they were supposed to have been generated. This raises the possibility that the STAP cells are the result of contamination, which is a perennial problem in cell culture laboratories. Wakayama did not observe any anomalies with the lines reported in the Nature papers, but, just to be safe, he sent those and other lines to an independent, and unnamed, lab for further examination and corroboration.
These independent tests, according to reports from Japanese media sources, have found that none of the STAP cell lines match the mouse strains they were supposed to be from. This calls “into question whether the STAP phenomenon has ever been demonstrated.”
Last week, the Nature News Blog reported that Dr. Obokata had agreed to retract one of the two STAP papers, even though the retraction has yet to appear in print. Now, according to the ScienceInsider, Obokata has consented to retracting both Nature papers. The ScienceInsider added this will not end the STAP story, since Riken is doggedly trying to determine whether the STAP phenomenon exists and as some critics are asking how these flawed papers were published in the first place.
“The science of the two papers was rigorously, robustly peer-reviewed as part of our usual editorial procedures. Any inaccuracies in the presentation of data that may have come to light since the peer review are being investigated,” a spokesperson from Nature told ScienceInsider.