SCIENTIFIC MISCONDUCT: Falsification Charge Highlights Image-Manipulation Standards  By: Gretchen Vogel

Controversy continues to plague work from the lab of prominent stem cell researcher Catherine Verfaillie. The University of Minnesota (UM) announced last week that an academic misconduct committee had concluded that Morayma Reyes, while a graduate student in Verfaillie's lab there, "falsified" four data images in figures in a 2001 stem cell article. The committee found that misconduct allegations against Verfaillie were unsubstantiated, but it did criticize her oversight and mentoring of lab personnel. The new charges come a year after questions were raised about the misuse of images in another key stem cell publication from the group (Science, 2 March 2007, p. 1207).

Reyes, now an assistant professor of pathology at the University of Washington (UW), Seattle, and Verfaillie, who now heads the Stem Cell Institute at the Catholic University of Leuven in Belgium, both acknowledge that errors were made in the preparation of the 2001 paper. But Verfaillie defends her supervision, and Reyes says that for several of the disputed images she merely globally adjusted the brightness and contrast in data images without any intent to deceive. "These errors were unintentional and were common and accepted practices at the time," Reyes wrote in an e-mail to Science.

The paper, published in Blood, claims that stem cells purified from human blood can form precursors of bone, fat, cartilage and muscle cells, as well as the endothelial cells that line blood vessels. At the time, blood stem cells weren't thought to be that versatile. Verfaillie and Reyes say the figure errors do not alter the Blood paper's conclusions, but Verfaillie has asked the journal to retract the paper, calling it "the proper course in this situation."

The Blood paper relates to work that the group later published in Nature, reporting that cells from mouse bone marrow could become a wide variety of cell types. Several groups have reported trouble reproducing that paper's results (Science, 9 February 2007, p. 760). Then last year, Nature conducted a re-review of the paper when a journalist at New Scientist questioned whether some data shown were identical to those in another paper. A UM investigation concluded that any duplication was the result of honest error. Nature published several corrections but said that the paper's conclusions were still valid and that Verfaillie continues to stand by the work.
READ ENTIRE ARTICLE AT SCIENCE          Science 17 October 2008: Vol. 322. no. 5900, p. 356 DOI: 10.1126/science.322.5900.356