WASP and Mst1 coregulate B-cell development and B-cell receptor signaling
Authors: Wenyan Li
Xin Dai
Yongjie Zhang
Chaohong Liu
Jinzhi Wang
Xiaodong Zhao
Lu Huang
Bebhinn Treanor
Xiaoming Bai
Di Yang
Panpan Jiang
Wenxia Song
Xiaoyu Sun
Heather Miller
Journal: Blood advances (2020)
Discipline: CLINICAL MEDICINE
Keywords: Mst1; WASP; B-cell development; BCR signaling; actin dynamics
Affiliations: Chongqing Key Laboratory of Child Infection and Immunity., Department of Pediatric Research Institute, and., Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China., Department of Pathogen Biology, School of Basic Medicine, Huazhong University of Science and Technology, Wuhan, China., Department of Dermatology and., Department of Hematology and Oncology, Children's Hospital of Chongqing Medical University, Chongqing, China., Department of Intracellular Pathogens, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT., Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD; and., Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada.

Abstract:  Mst1 is a serine/threonine kinase involved in cell survival, proliferation, apoptosis, and tumorigenesis. In mice, Mst1 regulates actin dynamics required for T-cell adhesion and migration, which correlate with thymic egress and entry into lymphatic tissue. The role of Mst1 in B cells and how it may control actin-dependent processes has not been well characterized. Wiskott-Aldrich syndrome protein (WASP) deficiency only moderately affects development and B-cell receptor (BCR) signaling, suggesting WASP likely associates with other molecules. We investigated whether Mst1 associates with WASP to regulate B-cell development and activation. Experimenting on Mst1/WASP double knockout (DKO) mice, we found a severe defect in the bone marrow B-cell development, and BCR signaling in the DKO mice was severely reduced. Even though WASP or Mst1 could influence the early B-cell activation, we found that the early activation events such as B-cell spreading, BCR clustering, and BCR signaling were much more impaired in the B cells from DKO mice. Furthermore, reciprocal regulation between Mst1 and WASP was observed in WASP and Mst1 KO mice, whereby the localization and function of phosphorylated WASP were affected in Mst1 KO mice. Most importantly, Mst1 inhibits the expression of WASP by decreasing the expression of WASP-interacting protein. Interestingly, we also found that WASP deficiency in patients and mice interferes with phosphorylated Mst1 localization and therefore function in B cells. Overall, our study provides a partner for WASP to regulate B-cell development and BCR signaling, as well as the reciprocal regulating molecular mechanism of one another. 

Retracted: No

PubPeer comments:
 This paper is part of a set of 5 papers. According to the authors, all papers are related to the same protocol approved under the number 12-016 by from the Ethics committee of the IHU Mu00e9diterranu00e9e infection (see article 1). Some of the authors are mentioned in the 5 papers. **One protocol, different studies ?** Among the 5 papers, Objectives are different, participants and cohorts are different and dates of recruitment are different. Depending on the papers, the study recruited -tpatients with Q fever (articles 1, 2 and 3) -tpatients with infective endocarditis (article 4) -tor patients with Q fever, patients with Whippleu2019s disease and Healthy volunteers (article 5) **Participants enrolled and data collected prospectively** All papers mention a prospective recruitment of participants and interventions are done to collect data (blood samples, hair samplesu2026). I could be considered that the protocol 12-016 is a prospective study. Except for one paper which do not mention the participant recruitment dates, all papers have recruited participants starting before and ending after the Year 2012. **Did the protocol get a retrospective ethics approval ?** According to the protocol approval number (12-016), we can assume with a good confidence that the ethics approval has been obtained in 2012. 4 papers describe a recruitment of participant starting before and ending after the Year 2012. As a consequence, Considering the data provided by the authors and the unique protocol number (nu00b012-016), readers may consider that the protocol: -tis not a retrospective study: authors mentioned a prospective recruitment in several papers and data have been collected after the ethical approval year. -thas started to prospectively recruit participants before to be approved by an ethics committee. As a reminder, retrospective ethics committee approval for a prospective interventional study is a serious breach of the Helsinki Declaration. In accordance with Editors guidances and Helsinki Declaration, if a prospective study has not been granted ethics committee approval prior to commencing, retrospective ethics approval cannot be obtained and it may not be possible to consider the manuscript for peer review. Could the authors and the Editors clarify asap the ethical approval process, the date of the participants recruitment ? If necessary, can the Editor explain why papers with retrospective ethical approval has been considered for peer-reviewing. **Did the protocol get the approval from the certified IRB?** In the article 1, authors mention that this ethics approval comes from the Ethics committee of the IHU Mu00e9diterranu00e9e infection. This ethics committee is affiliated to the same institution of some of the authors. In France, interventional prospective study MUST get an approval from certified IRB (aka Comitu00e9 de Protection des Personnes) before to start. The Ethics committee of the IHU Mu00e9diterranu00e9e infection is not on the list of the certified IRB and has not the ability to validate a prospective observational or interventional study. It would be in the public interest if the authors could -tdisclose the ethical approval form nu00b012-016. -tdetail the scope of the protocol approved by the ethics committee. **Different objectives** -t**Article 1:** to detect acute Q fever valvular injury to improve therapeutic management. -t**Article 2:** to describe persistent Coxiella burnetii cardiovascular infection on Bentall-De Bono prosthesis. -t**Article 3:** to assess the effectiveness of the current prevention strategy of endocartitis in Q fever patients by using a prolonged Antibiotic Treatment -t**Article 4:** to evaluate aPL, tested as anticardiolipin antibodies (IgG aCL) in infective endocarditis (IE) diagnosis -t**Article 5:** to create an assay for determining doxycycline levels and to use hair samples for monitoring the compliance over a longer period of time Could the author detail or disclose a copy of the protocol 12-016 in order to explain how a protocol can cover: -tDifferent objectives -tDifferent types of design -tDifferent types of samples -tDifferent period of recruitment with different type of participants. **Article 1: [Acute Q Fever Endocarditis: A Paradigm Shift Following the Systematic Use of Transthoracic Echocardiography During Acute Q Fever] ** The objective of the study is to detect acute Q fever valvular injury to improve therapeutic management. The authors mention that *sex, age, past medical history, underlying valvulopathy and echocardiographic data were prospectively collected by phone from 1991 to 2016* **Article 2: [Persistent Coxiella burnetii cardiovascular infection on Bentall-De Bono prosthesis] ** The aim of this study is to describe persistent Coxiella burnetii cardiovascular infection on Bentall-De Bono prosthesis. Participants were enrolled *between 1991 and February 2019*. Authors also mention a prospective collect of the data: *Samples were collected from international medical centers. Gender, age, past medical history, underlying valvulopathy, and echocardiographic data were collected prospectively by phone interview.* **Article 3: [Evolution From Acute Q Fever to Endocarditis Is Associated With Underlying Valvulopathy and Age and Can Be Prevented by Prolonged Antibiotic Treatment] ** The aim of this study is to assess the effectiveness of the current prevention strategy of endocartitis in Q fever patients by using a prolonged Antibiotic Treatment As described by the authors, the study has recruited *Acute Q fever patients followed by one of the authors (D.R.)* Participants *were included in a cohort study from January 2007 to December 2011 with the follow-up ending in May 2012.* This selection provide to the authors *access to a prospective collection of clinical, laboratory, and echocardiographic data using a standardized questionnaire.* As mentioned by the author the data has been prospectively collected. As a consequence, -tdata has been collected prospectively before and after the ethics committee approval in 2012. -tIt is not a retrospective study: authors mentioned a prospective recruitment and data have been collected after the ethical approval year. -tThe study started to prospectively recruit participants before to be approved by an ethics committee. For this article, the ethics approval in 2012 could be considered as a retrospective ethics approval. **Article 4: [Antiphospholipid antibodies proposed in the diagnosis of infective endocarditis] ** The aim of this study is to evaluate aPL, tested as anticardiolipin antibodies (IgG aCL) in infective endocarditis (IE) diagnosis As described by the authors, the participants have been enrolled *between November 2011 and February 2013*. The authors also describe a prospective recruitment: *all patients with a high suspicion of IE, hospitalized in the departments of cardiology, cardiac surgery, or internal medicine (University Hospital of Marseille), for whom an endocarditis kit was performed upon admission, were prospectively included in our study.* As a consequence, -tdata has been collected prospectively before and after the ethics committee approval in 2012. -tIt is not a retrospective study: authors mentioned a prospective recruitment and data have been collected after the ethical approval year. -tThe study started to prospectively recruit participants before to be approved by an ethics committee. For this article, the ethics approval in 2012 could be considered as a retrospective ethics approval. **Article 5: [Doxycycline assay hair samples for testing long-term compliance treatment](http: dx.doi.org 10.1016 j.jinf.2015.08.003)** The objective of the study is to create an assay for determining doxycycline levels and to use hair samples for monitoring the compliance over a longer period of time. The author mention that *the study was performed after ethical approval by the local ethics committee (number 12-016).* Author mention they * tested 14 patients treated with doxycycline* and they *u201ctested hair samples obtained from 20 control individualsu201d* This is an prospective study with patients and healthy participants. Can author confirm the date of the ethics approval of the protocol 12-016 and the date of recruitment of participants ? Authors have mentioned they have collected blood and hair samples only for the purpose of this study. In France, this type of study usually requires an approval from a certified IRB (Comitu00e9 de Protection des Personnes) Could the author confirm they obtained the approval from a Comitu00e9 de Protection des Personnes before to start the recruitment? In this case, could they provide the approval number and the date of approval. If not, could they explain the reasons? ,