Dr. Mamta Chawla-Sarkar, a senior scientist at ICMR’s NICED has 16 papers listed on PubPeer for image duplication and/or manipulation. Six of these papers were published when she was a Post-doc in Cleveland Clinic Foundation, Cleveland, Ohio. She is a Fellow of the National Academy of Science.

A senior scientist — Dr. Mamta Chawla-Sarkar — in Kolkata’s National Institute of Cholera and Enteric Diseases (ICMR-NICED) has 16 papers listed on PubPeer website for image duplication and/or manipulation. Besides the 16, a paper published in 2014 in PLOS ONE carries a correction for image duplication.

Ten papers listed on the website have been published when Dr. Chawla-Sarkar has been a scientist at NICED while the remaining papers were published when she was a Post-doc with Cleveland Clinic Foundation, Cleveland, Ohio, U.S.

Of the 10 papers published from NICED, she is a corresponding author in nine. She is only a co-author in all the six papers published from Cleveland.

All the papers with problematic images were verified by Dr. Elisabeth Bik, who is an expert in identifying duplication and manipulation in images. In addition, she had herself posted a few of Dr. Chawla-Sarkar’s papers with problematic images on PubPeer. In fact, on July 13, Dr. Bik did tweet one of Dr. Chawla-Sarkar’s manipulated images and asked if others could spot the manipulation.

Following the email interaction with her, the authors have responded on PubPeer for seven papers highlighted on the website. One of the responses is: “As authors, we have gone through the concern raised here. We would be communicating to the journal editor at the earliest with all the relevant data files.”

Though there is clear evidence of manipulation in many images, Dr. Chawla-Sarkar insists and vehemently denies image manipulation in any of her papers. Dr. Bik counters saying: “It is hard to imagine how duplicated bands within figures could have resulted by honest error.”

Dr. Chawla-Sarkar’s research focus

According to the NICED website, Dr. Chawla-Sarkar is “involved in studying two viruses namely influenza virus and rotavirus”. The focus of her research is “strain surveillance, host-virus interaction and identifying cellular proteins involved in viral pathogenesis for developing potential antiviral targets”. She oversees “influenza surveillance” in NICED and was “responsible for providing laboratory support for states in Eastern India during the A/H1N1 pandemic in 2009”.

In 2013, Dr. Chawla-Sarkar was elected Fellow of the National Academy of Science. She won the National Women Bioscientist Award given by the by Department of Biotechnology (DBT) in 2013. In recent years, she has won the ICMR Kshanika Oration Award 2017 and Fellowship of the West Bengal Academy of Science and Technology (FWAST) 2018.

Dr. Chawla-Sarkar’s defence

“As far as word image manipulation is concerned, I do not agree as we have not manipulated or fabricated any data. The blots are scanned predominantly by the scholars and assembled into final figure but why would they manipulate images when they have reproducible data. Repetitive background elements that are shown here might come from manual handling while developing and scanning and are completely unintentional. We were even unaware of these until pointed out by PubPeer,” she says in an email.

“… If I had doubts about data integrity, I would have made the student rerun the experiment and then communicate. It’s not difficult to rerun the experiments and get a cleaner blot once the protocol is set.”

“We all strive hard to establish our labs and thus I am not a fool to intentionally manipulate images/data to tarnish my image. In fact, for improving lab practices we have initiated uploading all raw data scans Figure/Panel wise for the reviewers/ Editor since 2014 so as the problems if any, are resolved in the beginning.”

“I am sure that the conclusions in the papers are valid because we repeat [the] experiment multiple times before conclusion [sic]; each conclusion in the figure is validated by at least two or three different assays. When a paper is submitted, reviewers are not satisfied until we prove the conclusion by multiple assays. Moreover, I check the raw data autorads when the data is presented in lab meetings,” she adds.

In response to a question whether junior authors would be responsible for image duplication and/or manipulations, she says: “The data is scanned and set into figures primarily by the first/second author as they perform the experiments. But as the draft of the manuscript is shared with all authors for comments and review before corresponding, we are all responsible for the manuscript and its criticism if any. As a corresponding author, I will definitely take the responsibility if the journal is not satisfied with the raw data we send to them.”

She then adds: “It is also impossible for me to check for repetitive background elements in the scanned images that we save. Still I would give benefits of doubt to the junior authors as I still cannot figure out why they would manipulate images when they have reproducible data. As I said earlier, I cannot and will not jeopardize the careers of junior authors by blaming them alone. If the journal finds us guilty, all the co-authors will take the blame.”

Correction to a 2014 paper

The 2014 paper in PLOS ONE carries a correction for the duplicated images. “For one of our paper in 2014 (prior to coming on PubPeer), there was an unintentional error on our side. We had sent the raw data to the journal editor. The editors agreed with the data reproducibility and issued a correction,” she says.

Besides listing out the corrections in the images, in the Correction notice, PLOS ONE notes: “At the journal’s request the authors provided copies of the original uncropped and unadjusted blots for all of the Western blots. Most of the blots represent the same image as the published article, but in some cases alternate blots from replicate experiments or different exposures of the same experiment have been provided… Upon evaluation of the raw blots provided by the authors, while the same overall trends in results were observed, the editors had concerns that they did not fully match the following published figures…”

The notice then adds: “The authors have conducted an internal replication study. Several experiments were repeated in conditions kept as similar as possible to those in the published study… The editors believe that these results from the published article are reproduced by this internal replication study.”

Problematic papers listed on PubPeer website

1) Nanotized PPARα Overexpression Targeted to Hypertrophied Myocardium Improves Cardiac Function by Attenuating the p53-GSK3β-Mediated Mitochondrial Death Pathway

Santanu Rana, Ritwik Datta, Ratul Datta Chaudhuri, Emeli Chatterjee, Mamta Chawla-Sarkar, Sagartirtha Sarkar

Antioxidants and Redox Signaling (2019)

2) Hsp90/Cdc37 assembly modulates TGFβ receptor-II to act as a profibrotic regulator of TGFβ signaling during cardiac hypertrophy

Ritwik Datta, Trisha Bansal, Santanu Rana, Kaberi Datta, Shiladitya Chattopadhyay, Mamta Chawla-Sarkar, Sagartirtha Sarkar

Cellular Signalling (2015) 

3) A spatio-temporal cardiomyocyte targeted vector system for efficient delivery of therapeutic payloads to regress cardiac hypertrophy abating bystander effect

Santanu Rana, Kaberi Datta, Teegala Lakshminarayan Reddy, Emeli Chatterjee, Preeta Sen, Manika Pal-Bhadra, Utpal Bhadra, Arindam Pramanik, Panchanan Pramanik, Mamta Chawla-Sarkar, Sagartirtha Sarkar

Journal of controlled release : official journal of the Controlled Release Society (2015)

4) Rotavirus-encoded nonstructural protein 1 modulates cellular apoptotic machinery by targeting tumor suppressor protein p53

Rahul Bhowmick, Umesh Chandra Halder, Shiladitya Chattopadhyay, Mukti Kant Nayak, Mamta Chawla-Sarkar

Journal of Virology (2013) 

5) Molecular mechanism behind rotavirus NSP1-mediated PI3 kinase activation: interaction between NSP1 and the p85 subunit of PI3 kinase

Parikshit Bagchi, Satabdi Nandi, Mukti Kant Nayak, Mamta Chawla-Sarkar

Journal of Virology (2013)

6) Rotaviral enterotoxin nonstructural protein 4 targets mitochondria for activation of apoptosis during infection

Rahul Bhowmick, Umesh Chandra Halder, Shiladitya Chattopadhyay, Shampa Chanda, Satabdi Nandi, Parikshit Bagchi, Mukti Kant Nayak, Oishee Chakrabarti, Nobumichi Kobayashi, Mamta Chawla-Sarkar

Journal of Biological Chemistry (2012)

7) Active participation of cellular chaperone Hsp90 in regulating the function of rotavirus nonstructural protein 3 (NSP3)

Dipanjan Dutta, Shiladitya Chattopadhyay, Parikshit Bagchi, Umesh Chandra Halder, Satabdi Nandi, Anupam Mukherjee, Nobumichi Kobayashi, Koki Taniguchi, Mamta Chawla-Sarkar

Journal of Biological Chemistry (2011)

8) Cell death regulation during influenza A virus infection by matrix (M1) protein: a model of viral control over the cellular survival pathway

U C Halder, P Bagchi, S Chattopadhyay, D Dutta, M Chawla-Sarkar

Cell Death and Disease (2011)

9) Rotavirus nonstructural protein 1 suppresses virus-induced cellular apoptosis to facilitate viral growth by activating the cell survival pathways during early stages of infection

Parikshit Bagchi, Dipanjan Dutta, Shiladitya Chattopadhyay, Anupam Mukherjee, Umesh Chandra Halder, Sagartirtha Sarkar, Nobumichi Kobayashi, Satoshi Komoto, Koki Taniguchi, Mamta Chawla-Sarkar

Journal of Virology (2010) 

10) The molecular chaperone heat shock protein-90 positively regulates rotavirus infectionx

Dipanjan Dutta, Parikshit Bagchi, Arunachal Chatterjee, Mukti Kant Nayak, Anupam Mukherjee, Shiladitya Chattopadhyay, Shigeo Nagashima, Nobumichi Kobayashi, Satoshi Komoto, Koki Taniguchi, Mamta Chawla-Sarkar

Virology (2009) 

11) Myocardial cell death and regeneration during progression of cardiac hypertrophy to heart failure

Sagartirtha Sarkar, Mamta Chawla-Sarkar, David Young, Kazutoshi Nishiyama, Mary E. Rayborn, Joe G. Hollyfield, Subha Sen

Journal of Biological Chemistry (2004)

12) Downregulation of Bcl-2, FLIP or IAPs (XIAP and survivin) by siRNAs sensitizes resistant melanoma cells to Apo2L/TRAIL-induced apoptosis

M Chawla-Sarkar, S I Bae, F J Reu, B S Jacobs, D J Lindner, E C Borden

Cell Death and Differentiation (2004)

13) Suppression of NF-kappa B survival signaling by nitrosylcobalamin sensitizes neoplasms to the anti-tumor effects of Apo2L/TRAIL

Mamta Chawla-Sarkar, Joseph A. Bauer, Joseph A. Lupica, Bei H. Morrison, Zhuo Tang, Rhonda K. Oates, Alex Almasan, Joseph A. DiDonato, Ernest C. Borden, Daniel J. Lindner

Journal of Biological Chemistry (2003)

14) IFN-beta pretreatment sensitizes human melanoma cells to TRAIL/Apo2 ligand-induced apoptosis

Mamta Chawla-Sarkar, Douglas W. Leaman, Barbara S. Jacobs, Ernest C. Borden

Journal of immunology (Baltimore, Md. : 1950) (2002)

15) Resistance to interferons in melanoma cells does not correlate with the expression or activation of signal transducer and activator of transcription 1 (Stat1)

Mamta Chawla-Sarkar, Douglas W. Leaman, Barbara S. Jacobs, Ralph J. Tuthill, Moitreyee Chatterjee-Kishore, George R. Stark, Ernest C. Borden

Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research (2002)

16) Preferential induction of apoptosis by interferon (IFN)-beta compared with IFN-alpha2: correlation with TRAIL/Apo2L induction in melanoma cell lines

M Chawla-Sarkar, D W Leaman, E C Borden

Clinical Cancer Research (2001)

Corrected Paper 

1) MAVS protein is attenuated by rotavirus nonstructural protein 1

Satabdi Nandi, Shampa Chanda, Parikshit Bagchi, Mukti Kant Nayak, Rahul Bhowmick, Mamta Chawla-Sarkar

PLOS ONE (2014)