Academic Publishing Research integrity

How David Ojcius and Jie Yan solved Leptospirosis

Beware of Chinese collaborators bearing gift authorships!

Biophysicist and human pathogen researcher David Ojcius, born in Brazil in 1957, is certainly not a child anymore but he still loves getting presents. And a kind and generous man from China, Jie Yan, is eager to give. Now Ojcius’ greed might become a liability, because the gift authorships he was given by Yan (and another kind friend) proved to be poisonous.

Ojcius used to be tenured researcher at the famous Institut Pasteur in Paris and professor at the Université Paris 7. In 2004, he moved to California, where he spent 11 years as professor at University of California, Merced, and since 2015, as professor at University of the Pacific in San Francisco, for some reason at the school of dentistry. In all those years, Ojcius has been publishing many studies where his name and affiliation are the only non-Chinese ones. The papers were exposed by Elisabeth Bik and other anonymous commenter(s) on PubPeer as hilariously fraudulent. There are presently almost 30 papers, not all of them were co-authored with Yan.

Infection disease researcher Jie Yan is a bigwig in China. He spent his entire career at the Zhejiang Medical University where he became full professor after a brief stint to get an MD degree in Germany, University of Lübeck (as aside, some of Lübeck’s infectious disease research here). Yan is also associate director of State Key Laboratory of Infectious Disease Prevention and Control and holder of 12 grants from National Natural Science Foundation of China. The papers Yan’s lab published with Ojcius are mostly about the therapies to treat leptospirosis, a dangerous bacterial infectious disease in China and other developing world nations. Together these gentlemen have allegedly been working hard to develop a working vaccine, because there is no good one for humans presently. Fake vaccine research is something particularly unpleasant, but here we are, others do it, too.

What did the polyglot Ojcius contribute to Yan’s research scientifically, except maybe his knowledge of English, one wonders? In any case, the Californian dental school professor is now under suspicion of research malfeasance, because in the very favourable version, Ojcius has been eagerly accepting gift authorships over many years.

It all started with one paper, in the journal Microbes and Infection, published by the Institut Pasteur, where Ojcius just happens to be Editor-in-Chief for already 10 years (and associate editor for 11 years before that). An anonymous PubPeer user started posting evidence, and Elisabeth Bik soon joined. Disaster unfolded.

Komi Koukoura Komi, Yu-Mei Ge, Xiao-Yang Xin, David M. Ojcius, Dexter Sun, Wei-Lin Hu, Xin Zhao, Xu’ai Lin, Jie Yan ChpK and MazF of the toxin–antitoxin modules are involved in the virulence of Leptospira interrogans during infection Microbes and Infection (2015) doi: 10.1016/j.micinf.2014.10.010

Figure 2: “While the bands highlighted in green are not identical, they share common features in contours and noise patterns.”
Bik: “I hope the Editor in Chief holds his own papers to the same high standards as he would with papers by others
Also, the red rectangled section comes from Figure 4 of Li et al Innate immunity 2010, also from Yan lab.
Very flawed cytometry
Figure 5A/B
Figure 2A

It is all very, very fake. The last author Jie Yan replied on PubPeer:

We thank the readers for identifying problems with the data. We are very sorry that the manuscript had these issues. I am contacting the other co-authors and we will also inform the journal.

The journal, aka its editor David Ojcius, was already aware, he even reacted by blocking me on Twitter (Ojcius used to follow me before). Now the Chief Editor of will decide what to do about his own paper. Unless Institut Pasteur politely asks him to resign?

As you already might have noticed, that Microbes and Infection paper reuses figures from two other papers from Yan lab, the aforementioned Li et al Innate Immunity 2010 (where Ojcius is second author), and this one:

Lei Zhang, Chenglin Zhang, David M. Ojcius, Dexter Sun, Jinfang Zhao, Xuai Lin, Liwei Li, Lanjuan Li, Jie Yan The mammalian cell entry (Mce) protein of pathogenic Leptospira species is responsible for RGD motif-dependent infection of cells and animals Molecular Microbiology (2012) doi: 10.1111/j.1365-2958.2012.07985.x

Compare Figure 1D to “Figure 4 from Haiyan Dong et al, 2008

All those Photoshop-fabricated microscopy images, tsk tsk. That paper in turn reuses data from Dong et al BMC Microbiology 2008, where of course Ojcius is again co-author.

Yan commented also here:

Thank you for bringing this issue to our attention. We are checking the data and will contact the journal for advice.

But of course there is much more, because Yan’s lab is very, ahem, ‘productive’ and Ojcius was always eager to be co-author. Here another case of data reuse between papers.

Liwei Li, David M. Ojcius, Jie Yan Comparison of invasion of fibroblasts and macrophages by high- and low-virulence Leptospira strains: colonization of the host-cell nucleus and induction of necrosis by the virulent strain Archives of Microbiology (2007) doi: 10.1007/s00203-007-0280-3

That paper shares image data with Liu et al Medical Microbiology and Immunology 2007, only recoloured, and even more revealing: the micrographs were digitally retouched to remove some small fragments. That other paper does not list Ojcius as co-author though, for reasons unknown. It features a regular co-author of Yan’s (and obviously another gift authorship grifter like Ojcius’), a certain Dexter Sun, neurologist and “voluntary faculty” at Weill Cornell Medicine. Now you might be rubbing your hands and saying hahaha, now the elite Cornell University in New York will be cracking down on those naughty rascals and their fake data: don’t hold your breath (pun intended), because do read about the Dean of Weill Cornell Medical School, Professor Augustine MK Choi here.

Now, let me show you a case of data reuse between three papers by Yan, Ojcius and Sun.

Shi-Lei Dong, Wei-Lin Hu, Yu-Mei Ge, David M Ojcius, Xu’ai Lin, Jie Yan A leptospiral AAA+ chaperone–Ntn peptidase complex, HslUV, contributes to the intracellular survival of Leptospira interrogans in hosts and the transmission of leptospirosis Emerging Microbes & Infections (2017) doi: 10.1038/emi.2017.93

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 (2014) doi: 10.1093/infdis/jit659

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 (2020) doi: 10.1093/infdis/jiaa176

Yan: “For Fig 1, we are repeating the experiment in order to answer your question.”

This is how Yan and colleagues plan to treat Leptospirosis infections, with research fraud. They even recently published such technology in eLife. Let’s see how this prestigious journal reacts, because its Editor-in-Chief is a big fan of my work.

Yang Li, Kai-Xuan Li, Wei-Lin Hu, David M Ojcius, Jia-Qi Fang, Shi-Jun Li, Xu’ai Lin, Jie Yan Endocytic recycling and vesicular transport systems mediate transcytosis of Leptospira interrogans across cell monolayer eLife (2019) doi: 10.7554/elife.44594 

That paper’s Figure 1C happens to share data (you are not surprised anymore, right?) with Figure 1B from yet another Yan lab production, of course with Ojcius as co-author. That paper has of course also problems of its own:

Peng Du, Shi-Jun Li, David M. Ojcius, Kai-Xuan Li, Wei-Lin Hu, Xu’ai Lin, Ai-Hua Sun, Jie Ya A novel Fas-binding outer membrane protein and lipopolysaccharide of Leptospira interrogans induce macrophage apoptosis through the Fas/FasL-caspase-8/-3 pathway Emerging Microbes & Infections (2018) doi: 10.1038/s41426-018-0135-9 

That is truly Flawed Cytometry, as Elisabeth Bik calls it. So far, Yan and Ojcius suffered only one retraction, for their common paper in Journal of Biological Chemistry. It happened already in March 2012 (see Bik’s “‘post-mortem’ analysis” here). Incidentally, Ojcius used to be “Member of Editorial Board” of this same journal, according to his CV between 2006 and 2011, go figure why he stopped being on-board just when the retraction was formalised.

Now a collage of various papers from Yan lab, all featuring Ojcius as co-author. But please continue reading after that because I have a small surprise.

Hu et al Cellular Microbiology 2013. Same picture of empty gel stands in also for p53 blot in Figure 5A, for completely different samples and experiment.
Luo et al Vaccine 2009. Yan replies: “We are repeating the experiment and will contact the journal for advice.”
Li et al J Medical Microbiology 2014. Also Figures 4C and Figure 5A contain cloned image elements.
Fang et al EBioMedicine 2018. In another flaw cytometry panel, the authors were swinging the digital eraser too broadly.
Hu et al Frontiers In Cell Infect Microbiol 2017. Yan writes: “Although this paper was published in 2017, this part of the figure was based on experiments done in 2008 by the second author. We no longer have the original data and are repeating the experiment.
Li et at Microbes & Infection 2018. Another one from the Pasteur Institut journal where Ojcius is Editor-in-Chief.
Zhao et al PLOS One 2013. Yan writes: “We will check the data and contact the journal for advice.
Wang et al PLOS One 2012. Yan writes: “The data is 10 years old, and we need to repeat the experiment.”
Chen et al PLOS One 2017.

Now, befroe the promised surprise, a paper from Ojcius own lab, from back in Paris:

Özlem Yilmaz, Thomas Jungas, Philippe Verbeke, David M. Ojcius Activation of the phosphatidylinositol 3-kinase/Akt pathway contributes to survival of primary epithelial cells infected with the periodontal pathogen Porphyromonas gingivalis Infection and Immunity (2004) doi: 10.1128/iai.72.7.3743-3751.2004

some unexpectedly similar features in different panels” in Figure 1B

Flawed cytometry again! And one can’t blame Yan now….

Now, we are almost there. Suspense is rising! These two papers were co-authored by Ojcus during and after his tenure at Institut Pasteur in Paris. They stem from a certain Parisian apoptosis research lab which my regular readers hopefully came to cherish:

Boya et al J Experimental Medicine 2003

Flawed cytometry and recycled western blot bands, who might it be?

This last author and collaborator of Ojcius is:


Basically, Ojcius is yet another friend and co-author of France’s star scientist, German Academy member and Italy’s quasi-Nobelist Guido Kroemer, who were caught with manipulated data in their other papers!

Which leads me to establish the Kroemer-rule of Biomedicine:

Everyone who ever published a paper with Guido Kroemer is worth having their science scrutinised by Elisabeth Bik, Clare Francis, Smut Clyde and other data integrity experts.


If you are interested to support my work, you can leave here a small tip of $5. Or several of small tips, just increase the amount as you like (2x=€10; 5x=€25). Your generous patronage of my journalism is needed now!


4 comments on “How David Ojcius and Jie Yan solved Leptospirosis

  1. Its funny how you make Guido appear dramatically at the end of the article to be the Darth Vader of science, orchestrating the (and all) evil in scientific research. Your dramatic flair is a credit to your upbringings (although, I don’t know in Ukranians have the dramatic writing reputation as the Russians do).

    Would you please go back to referring to your readers in your articles as “failed scientists?” I always get a chuckle from that, and I miss it. I guess its sort of analogous (perhaps) the immediately pleasant sting of a lash before I feel the real pain. Hurt me, hurt me (1980’s American popular slang)


  2. interesting read. Reminds me the math papermill case where many Chinese authors would make up a virtual non-Chinese co-author or corresponding, aiming (I guess) to boost their chance of getting manuscripts accepted. At least Ojcius does physically exist! Yan’s apparently smarter than the mathematicians.


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