Publications by authors named "Mart M Lamers"

20 Publications

  • Page 1 of 1

Human airway cells prevent SARS-CoV-2 multibasic cleavage site cell culture adaptation.

Elife 2021 Apr 9;10. Epub 2021 Apr 9.

Viroscience Department, Erasmus MC, Rotterdam, Netherlands.

Virus propagation methods generally use transformed cell lines to grow viruses from clinical specimens, which may force viruses to rapidly adapt to cell culture conditions, a process facilitated by high viral mutation rates. Upon propagation in VeroE6 cells, SARS-CoV-2 may mutate or delete the multibasic cleavage site (MBCS) in the spike protein. Previously, we showed that the MBCS facilitates serine protease-mediated entry into human airway cells (Mykytyn et al., 2021). Here, we report that propagating SARS-CoV-2 on the human airway cell line Calu-3 - that expresses serine proteases - prevents cell culture adaptations in the MBCS and directly adjacent to the MBCS (S686G). Similar results were obtained using a human airway organoid-based culture system for SARS-CoV-2 propagation. Thus, in-depth knowledge on the biology of a virus can be used to establish methods to prevent cell culture adaptation.
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http://dx.doi.org/10.7554/eLife.66815DOI Listing
April 2021

Duration and key determinants of infectious virus shedding in hospitalized patients with coronavirus disease-2019 (COVID-19).

Nat Commun 2021 01 11;12(1):267. Epub 2021 Jan 11.

Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.

Key questions in COVID-19 are the duration and determinants of infectious virus shedding. Here, we report that infectious virus shedding is detected by virus cultures in 23 of the 129 patients (17.8%) hospitalized with COVID-19. The median duration of shedding infectious virus is 8 days post onset of symptoms (IQR 5-11) and drops below 5% after 15.2 days post onset of symptoms (95% confidence interval (CI) 13.4-17.2). Multivariate analyses identify viral loads above 7 log RNA copies/mL (odds ratio [OR] of 14.7 (CI 3.57-58.1; p < 0.001) as independently associated with isolation of infectious SARS-CoV-2 from the respiratory tract. A serum neutralizing antibody titre of at least 1:20 (OR of 0.01 (CI 0.003-0.08; p < 0.001) is independently associated with non-infectious SARS-CoV-2. We conclude that quantitative viral RNA load assays and serological assays could be used in test-based strategies to discontinue or de-escalate infection prevention and control precautions.
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http://dx.doi.org/10.1038/s41467-020-20568-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7801729PMC
January 2021

SARS-CoV-2 entry into human airway organoids is serine protease-mediated and facilitated by the multibasic cleavage site.

Elife 2021 01 4;10. Epub 2021 Jan 4.

Viroscience Department, Erasmus University Medical Center, Rotterdam, Netherlands.

Coronavirus entry is mediated by the spike protein that binds the receptor and mediates fusion after cleavage by host proteases. The proteases that mediate entry differ between cell lines, and it is currently unclear which proteases are relevant in vivo. A remarkable feature of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike is the presence of a multibasic cleavage site (MBCS), which is absent in the SARS-CoV spike. Here, we report that the SARS-CoV-2 spike MBCS increases infectivity on human airway organoids (hAOs). Compared with SARS-CoV, SARS-CoV-2 entered faster into Calu-3 cells and, more frequently, formed syncytia in hAOs. Moreover, the MBCS increased entry speed and plasma membrane serine protease usage relative to cathepsin-mediated endosomal entry. Blocking serine proteases, but not cathepsins, effectively inhibited SARS-CoV-2 entry and replication in hAOs. Our findings demonstrate that SARS-CoV-2 enters relevant airway cells using serine proteases, and suggest that the MBCS is an adaptation to this viral entry strategy.
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http://dx.doi.org/10.7554/eLife.64508DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7806259PMC
January 2021

Susceptibility of rabbits to SARS-CoV-2.

Emerg Microbes Infect 2021 Dec;10(1):1-7

Viroscience department, Erasmus Medical Center, Rotterdam, the Netherlands.

Transmission of severe acute respiratory coronavirus-2 (SARS-CoV-2) between livestock and humans is a potential public health concern. We demonstrate the susceptibility of rabbits to SARS-CoV-2, which excrete infectious virus from the nose and throat upon experimental inoculation. Therefore, investigations on the presence of SARS-CoV-2 in farmed rabbits should be considered.
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http://dx.doi.org/10.1080/22221751.2020.1868951DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7832544PMC
December 2021

Development of immunohistochemistry and in situ hybridisation for the detection of SARS-CoV and SARS-CoV-2 in formalin-fixed paraffin-embedded specimens.

Sci Rep 2020 12 14;10(1):21894. Epub 2020 Dec 14.

Pathology Department, Animal and Plant Health Agency (APHA), Woodham Lane, New Haw, Addlestone, KT15 3NB, UK.

The rapid emergence of SARS-CoV-2, the causative agent of COVID-19, and its dissemination globally has caused an unprecedented strain on public health. Animal models are urgently being developed for SARS-CoV-2 to aid rational design of vaccines and therapeutics. Immunohistochemistry and in situ hybridisation techniques that facilitate reliable and reproducible detection of SARS-CoV and SARS-CoV-2 viral products in formalin-fixed paraffin-embedded (FFPE) specimens would be of great utility. A selection of commercial antibodies generated against SARS-CoV spike protein and nucleoprotein, double stranded RNA, and RNA probe for spike genes were evaluated for the ability to detect FFPE infected cells. We also tested both heat- and enzymatic-mediated virus antigen retrieval methods to determine the optimal virus antigen recovery as well as identifying alternative retrieval methods to enable flexibility of IHC methods. In addition to using native virus infected cells as positive control material, the evaluation of non-infected cells expressing coronavirus (SARS, MERS) spike as a biosecure alternative to assays involving live virus was undertaken. Optimized protocols were successfully applied to experimental animal-derived tissues. The diverse techniques for virus detection and control material generation demonstrated in this study can be applied to investigations of coronavirus pathogenesis and therapeutic research in animal models.
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http://dx.doi.org/10.1038/s41598-020-78949-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7736337PMC
December 2020

An organoid-derived bronchioalveolar model for SARS-CoV-2 infection of human alveolar type II-like cells.

EMBO J 2021 03 11;40(5):e105912. Epub 2021 Jan 11.

Viroscience Department, Erasmus University Medical Center, Rotterdam, The Netherlands.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), which may result in acute respiratory distress syndrome (ARDS), multiorgan failure, and death. The alveolar epithelium is a major target of the virus, but representative models to study virus host interactions in more detail are currently lacking. Here, we describe a human 2D air-liquid interface culture system which was characterized by confocal and electron microscopy and single-cell mRNA expression analysis. In this model, alveolar cells, but also basal cells and rare neuroendocrine cells, are grown from 3D self-renewing fetal lung bud tip organoids. These cultures were readily infected by SARS-CoV-2 with mainly surfactant protein C-positive alveolar type II-like cells being targeted. Consequently, significant viral titers were detected and mRNA expression analysis revealed induction of type I/III interferon response program. Treatment of these cultures with a low dose of interferon lambda 1 reduced viral replication. Hence, these cultures represent an experimental model for SARS-CoV-2 infection and can be applied for drug screens.
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http://dx.doi.org/10.15252/embj.2020105912DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883112PMC
March 2021

SARS-CoV-2 is transmitted via contact and via the air between ferrets.

Nat Commun 2020 07 8;11(1):3496. Epub 2020 Jul 8.

Department of Viroscience, Erasmus University Medical Center, Rotterdam, The Netherlands.

SARS-CoV-2, a coronavirus that emerged in late 2019, has spread rapidly worldwide, and information about the modes of transmission of SARS-CoV-2 among humans is critical to apply appropriate infection control measures and to slow its spread. Here we show that SARS-CoV-2 is transmitted efficiently via direct contact and via the air (via respiratory droplets and/or aerosols) between ferrets, 1 to 3 days and 3 to 7 days after exposure respectively. The pattern of virus shedding in the direct contact and indirect recipient ferrets is similar to that of the inoculated ferrets and infectious virus is isolated from all positive animals, showing that ferrets are productively infected via either route. This study provides experimental evidence of robust transmission of SARS-CoV-2 via the air, supporting the implementation of community-level social distancing measures currently applied in many countries in the world and informing decisions on infection control measures in healthcare settings.
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http://dx.doi.org/10.1038/s41467-020-17367-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7343828PMC
July 2020

SARS-CoV-2 productively infects human gut enterocytes.

Science 2020 07 1;369(6499):50-54. Epub 2020 May 1.

Oncode Institute, Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center, Utrecht, Netherlands.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause coronavirus disease 2019 (COVID-19), an influenza-like disease that is primarily thought to infect the lungs with transmission through the respiratory route. However, clinical evidence suggests that the intestine may present another viral target organ. Indeed, the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) is highly expressed on differentiated enterocytes. In human small intestinal organoids (hSIOs), enterocytes were readily infected by SARS-CoV and SARS-CoV-2, as demonstrated by confocal and electron microscopy. Enterocytes produced infectious viral particles, whereas messenger RNA expression analysis of hSIOs revealed induction of a generic viral response program. Therefore, the intestinal epithelium supports SARS-CoV-2 replication, and hSIOs serve as an experimental model for coronavirus infection and biology.
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http://dx.doi.org/10.1126/science.abc1669DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7199907PMC
July 2020

Comparative pathogenesis of COVID-19, MERS, and SARS in a nonhuman primate model.

Science 2020 05 17;368(6494):1012-1015. Epub 2020 Apr 17.

Department of Viroscience, Erasmus University Medical Center, Rotterdam, Netherlands.

The current pandemic coronavirus, severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), was recently identified in patients with an acute respiratory syndrome, coronavirus disease 2019 (COVID-19). To compare its pathogenesis with that of previously emerging coronaviruses, we inoculated cynomolgus macaques with SARS-CoV-2 or Middle East respiratory syndrome (MERS)-CoV and compared the pathology and virology with historical reports of SARS-CoV infections. In SARS-CoV-2-infected macaques, virus was excreted from nose and throat in the absence of clinical signs and detected in type I and II pneumocytes in foci of diffuse alveolar damage and in ciliated epithelial cells of nasal, bronchial, and bronchiolar mucosae. In SARS-CoV infection, lung lesions were typically more severe, whereas they were milder in MERS-CoV infection, where virus was detected mainly in type II pneumocytes. These data show that SARS-CoV-2 causes COVID-19-like disease in macaques and provides a new model to test preventive and therapeutic strategies.
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http://dx.doi.org/10.1126/science.abb7314DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7164679PMC
May 2020

Severe Acute Respiratory Syndrome Coronavirus 2-Specific Antibody Responses in Coronavirus Disease Patients.

Emerg Infect Dis 2020 Jul 21;26(7):1478-1488. Epub 2020 Jun 21.

A new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged to cause a human pandemic. Although molecular diagnostic tests were rapidly developed, serologic assays are still lacking, yet urgently needed. Validated serologic assays are needed for contact tracing, identifying the viral reservoir, and epidemiologic studies. We developed serologic assays for detection of SARS-CoV-2 neutralizing, spike protein-specific, and nucleocapsid-specific antibodies. Using serum samples from patients with PCR-confirmed SARS-CoV-2 infections, other coronaviruses, or other respiratory pathogenic infections, we validated and tested various antigens in different in-house and commercial ELISAs. We demonstrated that most PCR-confirmed SARS-CoV-2-infected persons seroconverted by 2 weeks after disease onset. We found that commercial S1 IgG or IgA ELISAs were of lower specificity, and sensitivity varied between the 2 assays; the IgA ELISA showed higher sensitivity. Overall, the validated assays described can be instrumental for detection of SARS-CoV-2-specific antibodies for diagnostic, seroepidemiologic, and vaccine evaluation studies.
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http://dx.doi.org/10.3201/eid2607.200841DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7323511PMC
July 2020

ADAR1: "Editor-in-Chief" of Cytoplasmic Innate Immunity.

Front Immunol 2019 25;10:1763. Epub 2019 Jul 25.

Department of Viroscience, Erasmus MC, Rotterdam, Netherlands.

Specialized receptors that recognize molecular patterns such as double stranded RNA duplexes-indicative of viral replication-are potent triggers of the innate immune system. Although their activation is beneficial during viral infection, RNA transcribed from endogenous mobile genetic elements may also act as ligands potentially causing autoimmunity. Recent advances indicate that the adenosine deaminase ADAR1 through RNA editing is involved in dampening the canonical antiviral RIG-I-like receptor-, PKR-, and OAS-RNAse L pathways to prevent autoimmunity. However, this inhibitory effect must be overcome during viral infections. In this review we discuss ADAR1's critical role in balancing immune activation and self-tolerance.
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http://dx.doi.org/10.3389/fimmu.2019.01763DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6669771PMC
October 2020

Multihospital Outbreak of a Middle East Respiratory Syndrome Coronavirus Deletion Variant, Jordan: A Molecular, Serologic, and Epidemiologic Investigation.

Open Forum Infect Dis 2018 May 28;5(5):ofy095. Epub 2018 Apr 28.

Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.

Background: An outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) in Jordan in 2015 involved a variant virus that acquired distinctive deletions in the accessory open reading frames. We conducted a molecular and seroepidemiologic investigation to describe the deletion variant's transmission patterns and epidemiology.

Methods: We reviewed epidemiologic and medical chart data and analyzed viral genome sequences from respiratory specimens of MERS-CoV cases. In early 2016, sera and standardized interviews were obtained from MERS-CoV cases and their contacts. Sera were evaluated by nucleocapsid and spike protein enzyme immunoassays and microneutralization.

Results: Among 16 cases, 11 (69%) had health care exposure and 5 (31%) were relatives of a known case; 13 (81%) were symptomatic, and 7 (44%) died. Genome sequencing of MERS-CoV from 13 cases revealed 3 transmissible deletions associated with clinical illness during the outbreak. Deletion variant sequences were epidemiologically clustered and linked to a common transmission chain. Interviews and sera were collected from 2 surviving cases, 23 household contacts, and 278 health care contacts; 1 (50%) case, 2 (9%) household contacts, and 3 (1%) health care contacts tested seropositive.

Conclusions: The MERS-CoV deletion variants retained human-to-human transmissibility and caused clinical illness in infected persons despite accumulated mutations. Serology suggested limited transmission beyond that detected during the initial outbreak investigation.
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http://dx.doi.org/10.1093/ofid/ofy095DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5965092PMC
May 2018

Chimeric camel/human heavy-chain antibodies protect against MERS-CoV infection.

Sci Adv 2018 08 8;4(8):eaas9667. Epub 2018 Aug 8.

Department of Viroscience, Erasmus Medical Center, Rotterdam, Netherlands.

Middle East respiratory syndrome coronavirus (MERS-CoV) continues to cause outbreaks in humans as a result of spillover events from dromedaries. In contrast to humans, MERS-CoV-exposed dromedaries develop only very mild infections and exceptionally potent virus-neutralizing antibody responses. These strong antibody responses may be caused by affinity maturation as a result of repeated exposure to the virus or by the fact that dromedaries-apart from conventional antibodies-have relatively unique, heavy chain-only antibodies (HCAbs). These HCAbs are devoid of light chains and have long complementarity-determining regions with unique epitope binding properties, allowing them to recognize and bind with high affinity to epitopes not recognized by conventional antibodies. Through direct cloning and expression of the variable heavy chains (VHHs) of HCAbs from the bone marrow of MERS-CoV-infected dromedaries, we identified several MERS-CoV-specific VHHs or nanobodies. In vitro, these VHHs efficiently blocked virus entry at picomolar concentrations. The selected VHHs bind with exceptionally high affinity to the receptor binding domain of the viral spike protein. Furthermore, camel/human chimeric HCAbs-composed of the camel VHH linked to a human Fc domain lacking the CH1 exon-had an extended half-life in the serum and protected mice against a lethal MERS-CoV challenge. HCAbs represent a promising alternative strategy to develop novel interventions not only for MERS-CoV but also for other emerging pathogens.
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http://dx.doi.org/10.1126/sciadv.aas9667DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6082650PMC
August 2018

Induction of Cross-Clade Antibody and T-Cell Responses by a Modified Vaccinia Virus Ankara-Based Influenza A(H5N1) Vaccine in a Randomized Phase 1/2a Clinical Trial.

J Infect Dis 2018 07;218(4):614-623

Department of Viroscience, Postgraduate School of Molecular Medicine, Erasmus Medical Center, Rotterdam, the Netherlands.

Background: High-pathogenicity avian influenza viruses continue to circulate in poultry and wild birds and occasionally infect humans, sometimes with fatal outcomes. Development of vaccines is a priority to prepare for potential pandemics but is complicated by antigenic variation of the surface glycoprotein hemagglutinin. We report the immunological profile induced by human immunization with modified vaccinia virus Ankara (MVA) expressing the hemagglutinin gene of influenza A(H5N1) virus A/Vietnam/1194/04 (rMVA-H5).

Methods: In a double-blinded phase 1/2a clinical trial, 79 individuals received 1 or 2 injections of rMVA-H5 or vector control. Twenty-seven study subjects received a booster immunization after 1 year. The breadth, magnitude, and properties of vaccine-induced antibody and T-cell responses were characterized.

Results: rMVA-H5 induced broadly reactive antibody responses, demonstrated by protein microarray, hemagglutination inhibition, virus neutralization, and antibody-dependent cellular cytotoxicity assays. Antibodies cross-reacted with antigenically distinct H5 viruses, including the recently emerged subtypes H5N6 and H5N8 and the currently circulating subtype H5N1. In addition, the induction of T cells specific for H5 viruses of 2 different clades was demonstrated.

Conclusions: rMVA-H5 induced immune responses that cross-reacted with H5 viruses of various clades. These findings validate rMVA-H5 as vaccine candidate against antigenically distinct H5 viruses.

Clinical Trials Registration: NTR3401.
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http://dx.doi.org/10.1093/infdis/jiy214DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6047453PMC
July 2018

Independent Effects of a Herbivore's Bacterial Symbionts on Its Performance and Induced Plant Defences.

Int J Mol Sci 2017 Jan 18;18(1). Epub 2017 Jan 18.

Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.

It is well known that microbial pathogens and herbivores elicit defence responses in plants. Moreover, microorganisms associated with herbivores, such as bacteria or viruses, can modulate the plant's response to herbivores. Herbivorous spider mites can harbour different species of bacterial symbionts and exert a broad range of effects on host-plant defences. Hence, we tested the extent to which such symbionts affect the plant's defences induced by their mite host and assessed if this translates into changes in plant resistance. We assessed the bacterial communities of two strains of the common mite pest . We found that these strains harboured distinct symbiotic bacteria and removed these using antibiotics. Subsequently, we tested to which extent mites with and without symbiotic bacteria induce plant defences in terms of phytohormone accumulation and defence gene expression, and assessed mite oviposition and survival as a measure for plant resistance. We observed that the absence/presence of these bacteria altered distinct plant defence parameters and affected mite performance but we did not find indications for a causal link between the two. We argue that although bacteria-related effects on host-induced plant defences may occur, these do not necessarily affect plant resistance concomitantly.
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http://dx.doi.org/10.3390/ijms18010182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5297814PMC
January 2017

Naturally occurring recombination in ferret coronaviruses revealed by complete genome characterization.

J Gen Virol 2016 09 7;97(9):2180-2186. Epub 2016 Jun 7.

Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.

Ferret coronaviruses (FRCoVs) exist as an enteric and a systemic pathotype, of which the latter is highly lethal to ferrets. To our knowledge, this study provides the first full genome sequence of a FRCoV, tentatively called FRCoV-NL-2010, which was detected in 2010 in ferrets in The Netherlands. Phylogenetic analysis showed that FRCoV-NL-2010 is most closely related to mink CoV, forming a separate clade of mustelid alphacoronavirus that split off early from other alphacoronaviruses. Based on sequence homology of the complete genome, we propose that these mustelid coronaviruses may be assigned to a new species. Comparison of FRCoV-NL-2010 with the partially sequenced ferret systemic coronavirus MSU-1 and ferret enteric coronavirus MSU-2 revealed that recombination in the spike, 3c and envelope genes occurred between different FRCoVs.
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http://dx.doi.org/10.1099/jgv.0.000520DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7079585PMC
September 2016

Deletion Variants of Middle East Respiratory Syndrome Coronavirus from Humans, Jordan, 2015.

Emerg Infect Dis 2016 Apr;22(4):716-9

We characterized Middle East respiratory syndrome coronaviruses from a hospital outbreak in Jordan in 2015. The viruses from Jordan were highly similar to isolates from Riyadh, Saudi Arabia, except for deletions in open reading frames 4a and 3. Transmissibility and pathogenicity of this strain remains to be determined.
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http://dx.doi.org/10.3201/eid2204.152065DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4806954PMC
April 2016

Usp12 stabilizes the T-cell receptor complex at the cell surface during signaling.

Proc Natl Acad Sci U S A 2016 Feb 25;113(6):E705-14. Epub 2016 Jan 25.

HKU-Pasteur Research Pole and Center for Influenza Research, School of Public Health, LKS Faculty of Medicine, University of Hong Kong, Hong Kong; Department of Cell Biology and Infection, Institut Pasteur, 75015 Paris, France;

Posttranslational modifications are central to the spatial and temporal regulation of protein function. Among others, phosphorylation and ubiquitylation are known to regulate proximal T-cell receptor (TCR) signaling. Here we used a systematic and unbiased approach to uncover deubiquitylating enzymes (DUBs) that participate during TCR signaling in primary mouse T lymphocytes. Using a C-terminally modified vinyl methyl ester variant of ubiquitin (HA-Ub-VME), we captured DUBs that are differentially recruited to the cytosol on TCR activation. We identified ubiquitin-specific peptidase (Usp) 12 and Usp46, which had not been previously described in this pathway. Stimulation with anti-CD3 resulted in phosphorylation and time-dependent translocation of Usp12 from the nucleus to the cytosol. Usp12(-/-) Jurkat cells displayed defective NFκB, NFAT, and MAPK activities owing to attenuated surface expression of TCR, which were rescued on reconstitution of wild type Usp12. Proximity-based labeling with BirA-Usp12 revealed several TCR adaptor proteins acting as interactors in stimulated cells, of which LAT and Trat1 displayed reduced expression in Usp12(-/-) cells. We demonstrate that Usp12 deubiquitylates and prevents lysosomal degradation of LAT and Trat1 to maintain the proximal TCR complex for the duration of signaling. Our approach benefits from the use of activity-based probes in primary cells without any previous genome modification, and underscores the importance of ubiquitin-mediated regulation to refine signaling cascades.
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http://dx.doi.org/10.1073/pnas.1521763113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4760780PMC
February 2016

Identification of protein receptors for coronaviruses by mass spectrometry.

Methods Mol Biol 2015 ;1282:165-82

Department of Viroscience, Erasmus Medical Center, 2040, Rotterdam, CA, 3000, The Netherlands.

As obligate intracellular parasites, viruses need to cross the plasma membrane and deliver their genome inside the cell. This step is initiated by the recognition of receptors present on the host cell surface. Receptors can be major determinants of tropism, host range, and pathogenesis. Identifying virus receptors can give clues to these aspects and can lead to the design of intervention strategies. Interfering with receptor recognition is an attractive antiviral therapy, since it occurs before the viral genome has reached the relative safe haven within the cell. This chapter describes the use of an immunoprecipitation approach with Fc-tagged viral spike proteins followed by mass spectrometry to identify and characterize the receptor for the Middle East respiratory syndrome coronavirus. This technique can be adapted to identify other viral receptors.
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http://dx.doi.org/10.1007/978-1-4939-2438-7_15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7121102PMC
November 2015

Isolation of MERS coronavirus from a dromedary camel, Qatar, 2014.

Emerg Infect Dis 2014 Aug;20(8):1339-42

We obtained the full genome of Middle East respiratory syndrome coronavirus (MERS-CoV) from a camel in Qatar. This virus is highly similar to the human England/Qatar 1 virus isolated in 2012. The MERS-CoV from the camel efficiently replicated in human cells, providing further evidence for the zoonotic potential of MERS-CoV from camels.
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http://dx.doi.org/10.3201/eid2008.140663DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4111206PMC
August 2014