Even as the U.S. senate debates on expanding federal funding for embryonic stem cell research, it may be remembered that the claims professed in many papers of adult stem cells becoming any specialised cells should be taken with a pinch of salt. That is even when the claims are published in reputed peer-reviewed journals.
The Bush administration lays much emphasis on the results of such results to buttress its claim that adult stem cells are indeed as versatile as embryonic stem cells.
The research done by Catherine Verfaillie, of the University of Minnesota in Minneapolis is the kind of work that the Bush administration eagerly awaits using adult stem cells that possess the ability to become many kinds of body tissues.
A great setback
Unfortunately for the administration, the researcher’s findings are proving to be controversial. She is doing them more harm than good. Much like some of the other studies that had unsuccessfully tried to prove the pluripotency of adult stem cells, this study has gone to prove that banking solely on adult stem cell research, at the cost of embryonic stem cell research, may not be right after all.
And in many ways the modus operandi of the researcher is similar to those used by the now “famous” South Korean researcher Hwang Woo Suk.
The researcher, who first published her results in Nature in 2002, had used adult stem cells from bone marrow to grow into many specialised tissues. The only give away was that Verfaillie claimed to have used stem cells from bone marrow. And this led New Scientist to investigate the veracity of her claims.
“This was a surprise, because adult stem cells can generally form only a narrow range of tissue types,” noted New Scientist (March 21, 2007). And the first proof of a fake research shows up when other researchers are unable to replicate the work. Worse, Verfaillie and her team were themselves unable to isolate the cells multipotent adult progenitor cells (MAPS) for six months after publishing the paper in Nature.
Much like what Hwang did, Verfaillie had used the same images more than once in a paper published in the journal Blood in 2001 to represent different body tissues being obtained from the stem cells.All that was required to dodge the `eagle’ eyes of the peer-reviewers of the journal was to flip the images and make small changes to them to make them appear as different images.
The magnitude of the problem and the difficulty in identifying this by the peer-reviewers were brought out when the Hwang episode was in the news. But if it is indeed that difficult to identify image manipulation and duplication, then New Scientist and the experts that the magazine got in touch with were able to prove that it was not as difficult as the journals claimed to be.
Image manipulation and duplication could have still been discounted as yet another fraud by an `over-enthusiastic’ researcher. But unlike the Hwang episode, the isolation and use of MAPS have been patented. Verfaillie is one of names mentioned in the patent.
New Scientist found the three images used in the patent were nothing but those used in the Blood paper. But what literally sealed all her fire exits was that the duplicated images in the patent, unlike in the Blood journal, represented different body tissues!
And it is not just the images that Verfaillie duplicated while publishing in other journals. Six plots that described the distinctive “marker” molecules carried on the surface of the cells and published in the Nature journal were also used in the Experimental Hematology journal the same year. The Experimental Hematology paper was supposed to have been based on experiments performed on different mice and representing different cells.
The credibility of Verfaillie took a beating in February this year when she was compelled to get in touch with Nature and Experimental Hematology to inform them that the plots in both the papers “should not be relied upon as accurate representations of MAPC marker plots.” Surely, Verfaillie has failed Mr. Bush on more than one count. And what a time to do it.