On the perils of scientific collaboration from thousands of miles away

Collaborations can be fraught. Ask David Ojcius. 

Ojcius, an emeritus professor of molecular and cell biology at the University of California, Merced, and a department chair at the University of the Pacific, is up to four retractions, five corrections and an expression of concern in papers he wrote with collaborators in China and elsewhere. 

Ojcius is the editor-in-chief of Microbes and Infection, which has retracted one of his papers and corrected another. 

However, Ojcius’ name generally appears as a middle author on the papers, suggesting his contribution wasn’t central to the preparation of the articles. Indeed, in at least one of the articles — a 2014 paper in PLOS ONE that has received an expression of concern — Ojcius was listed as having been responsible for reviewing the data but not collecting it or preparing any of the figures. 

Ojcius told us in an email that he edited the papers “for grammar and scientific clarity” and that he has 

not seen any evidence to suggest that the first authors [whom he says were in charge of preparing the figures] had duplicated images intentionally. 

The retracted papers were published between 2011 and 2019. The most recent removal involves a 2017 article in Emerging Microbes & Infections (EM&I)– a Taylor & Francis journal — titled “A leptospiral AAA+ chaperone–Ntn peptidase complex, HslUV, contributes to the intracellular survival of Leptospira interrogans in hosts and the transmission of leptospirosis.” 

Elisabeth Bik flagged the article on PubPeer last year, noting her suspicions about the figures. In a comment on her post, a person claiming to be Jie Yan, the last author on the paper, wrote: 

We thank the readers for the comment. We are very sorry that the manuscript had these issues. I am contacting the other co-authors to check the data. We are repeating the experiment and will contact the journal for advice.

Another 30 entries on PubPeer link to papers by Ojcius dating back to this 2003 article in the Journal of Experimental Medicine.

According to the notice for the 2017 paper in EM&I: 

This article is being retracted due to reuse of images from other articles by the same authors, representing different results.

This includes a histopathology panel from Figure 7A (Wild-type 3d/Kidney), which can be found in the following article, where it is presented as Figure 5 (ΔMPI/Kidney 7d), with slightly altered rotation and staining:

Yu-Mei Ge, Ai-Hua Sun, David M Ojcius, Shi-Jun Li, Wei-Lin Hu, Xu’ai Lin, Jie Yan, M16-Type Metallopeptidases Are Involved in Virulence for Invasiveness and Diffusion of Leptospira interrogans and Transmission of Leptospirosis, The Journal of Infectious Diseases, Volume 222, Issue 6, 15 September 2020, Pages 1008–1020, DOI: 10.1093/infdis/jiaa176

In addition, a Leptospira cell staining panel from Figure 7E (7 d/ΔhsIUB) was found to have been presented as a result from an earlier experiment, within urine of a different strain of hamsters, within Figure 5D (7(100x)/ Wild-type strain) of the following article:

Kokouvi Kassegne, Weilin Hu, David M. Ojcius, Dexter Sun, Yumei Ge, Jinfang Zhao, X. Frank Yang, Lanjuan Li, Jie Yan, Identification of Collagenase as a Critical Virulence Factor for Invasiveness and Transmission of Pathogenic Leptospira Species, The Journal of Infectious Diseases, Volume 209, Issue 7, 1 April 2014, Pages 1105–1115, DOI: 10.1093/infdis/jit659

When approached for an explanation, the authors were unable to provide an explanation or verify their original data. The authors wish to apologize for their errors and the resulting inconvenience. The authors agree with the decision to retract this article.

Neither of those papers is among the retracted or flagged articles we mentioned above. 

Another paper in EM&I by Ojcius and Yan, from 2018, received a correction earlier this year. According to the statement: 

The authors state that there was a duplication of panels in Figure 4A, which mistakenly took place when they assembled the composite Figure 4A, which contained 18 small panels, during the resubmission process.

In the original Figure 4A, the Wild type/2 h panel is identical to the Scramble siRNA/1 h panel and the Wild type/24 h panel is identical to the Scramble siRNA/24 h panel.

In this corrected version of Figure 4, Scramble siRNA/1 h panel and the Scramble siRNA/24 h panel of the Figure 4A are replaced with the corresponding representative image, respectively.

The Figure 4A in the study aimed to show that siRNA significantly decreased the NLRP3 expression but the scramble siRNA (control siRNA) did not significantly decrease the NLRP3 expression in THP-1 cells. Scramble siRNA control was used to verify the effectiveness of NLRP3 siRNA in the NLRP3 expression. The authors are convinced that the mistake in the placement of the panel does not affect the interpretation of this experiment nor the conclusion of the study.

The authors would like to note that the only changes are to the panels of Fig 4A scramble siRNA 1 h and Fig 4A scramble siRNA 24 h, and the rest of the figures are identical to the original published version.

The authors apologize to the Editors of journal Microbe and Infection and to the readership for any inconvenience caused.

The expression of concern for the PLOS ONE paper, titled “Identification of CD24 as a Cancer Stem Cell Marker in Human Nasopharyngeal Carcinoma,” indicates that at least one institution has conducted an investigation into the work. The notice states that: 

Chang Gung University looked into this matter and clarified that, while the authors retained the lab notebooks as well as some raw materials and data for this experiment (i.e., paraffin-embedded tissues and images of mice), the information found in the lab notebooks was incomplete and some images of mice for Fig 7B are no longer available. Hence, we have been unable to fully clarify the issues about the published figure [1].

Ojcius told us: 

The first author of each article was primarily responsible for preparing figures for the articles. Several authors in the lab of my colleague, Jie Yan, participated in experiments and also contributed figures to some of the articles.

Based on the figures that were presented to me, I helped to revise text for grammar and scientific clarity. Without the help of image analysis tools, it would have been nearly impossible to detect image duplications before the manuscripts were submitted. As these image analysis tools become available to journals and authors, I hope that other journals and authors will avoid these problems in the future.

All the experiments were performed in the lab of the corresponding author, Jie Yan. Nobody else from my group in the US was involved in these projects.

Ojcius added that: 

I have known Jie Yan for a long time, and I have no reason to suspect that he was aware of the image duplications. The emails between the first authors that I saw suggest that the authors stored image files on the same lab computer, which was shared with other students and researchers in the lab. I have not seen any evidence to suggest that the first authors had duplicated images intentionally.

The only exception that is difficult for me to understand is the article in Microbes and Infection, which was retracted by the journal.

I have not been in contact with the first author, who had published one article in China before returning to his home country.

It may be difficult to ever determine why so many images were duplicated. I doubt that the university in China will conduct an investigation to analyze lab notebooks or the lab computer, since Jie Yan had serious health issues at the beginning of 2020 and was already scheduled to retire at the end of 2020.

Ojcius said one lesson from the ill-fated collaborations was this: 

I would recommend that researchers use an image-analysis tool like Proofig.  This and similar tools are now becoming widely available. I would recommend this type of image-analysis tool to all labs that publish complicated multi-panel figures, whether or not they collaborate with other groups.

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