Publications

Notable Recent Publications

These are some recent publications which give a flavour of the research from the Barclay lab. For a complete list of publications, please see below.

Species difference in ANP32A underlies influenza A virus polymerase host restriction. Nature (2016).
Jason S. Long, Efstathios S. Giotis, Olivier Moncorgé, Rebecca Frise, Bhakti Mistry, Joe James, Mireille Morisson, Munir Iqbal, Alain Vignal, Michael A. Skinner & Wendy S. Barclay

This paper identified a key factor that explained why the polymerases from avian influenza viruses are restricted in humans.  For more, please see the associated New and Views.

See our latest ANP32 papers here: eLIFE, Journal of Virology, Journal of Virology.

The mechanism of resistance to favipiravir in influenza. PNAS (2018).
Daniel H. Goldhill, Aartjan J. W. te Velthuis, Robert A. Fletcher, Pinky Langat, Maria Zambon, Angie Lackenby & Wendy S. Barclay

This paper showed how influenza could evolve resistance to favipiravir, an antiviral that may be used to treat influenza. The residue that mutated to give resistance was highly conserved suggesting that the mechanism of resistance may be applicable to other RNA viruses.

Internal genes of a highly pathogenic H5N1 influenza virus determine high viral replication in myeloid cells and severe outcome of infection in mice. Plos Path. (2018).
Hui Li*, Konrad C. Bradley*, Jason S. Long, Rebecca Frise, Jonathan W. Ashcroft, Lorian C. Hartgroves, Holly Shelton, Spyridon Makris, Cecilia Johansson, Bin Cao & Wendy S. Barclay

Why do avian influenza viruses like H5N1 cause such severe disease in humans? This paper demonstrated that H5N1 viruses replicate better than human viruses in myeloid cells from mice leading to a cytokine storm and more severe disease.

Search or filter publications

Filter by type:

Filter by publication type

Filter by year:

to

Results

  • Showing results for:
  • Reset all filters

Search results

  • Report
    Riley S, Walters C, Wang H, Eales O, Ainslie K, Atchison C, Fronterre C, Diggle PJ, Ashby D, Donnelly C, Cooke G, Barclay W, Ward H, Darzi A, Elliott Pet al., 2020,

    REACT-1 round 7 updated report: regional heterogeneity in changes in prevalence of SARS-CoV-2 infection during the second national COVID-19 lockdown in England

    , REACT-1 round 7 updated report: regional heterogeneity in changes in prevalence of SARS-CoV-2 infection during the second national COVID-19 lockdown in England, London, Publisher: Imperial College London

    BackgroundEngland exited a four-week second national lockdown on 2nd December 2020 initiated in response to the COVID-19 pandemic. Prior results showed that prevalence dropped during the first half of lockdown, with greater reductions in higher-prevalence northern regions.MethodsREACT-1 is a series of community surveys of SARS-CoV-2 RT-PCR swab-positivity in England, designed to monitor the spread of the epidemic and thus increase situational awareness. Round 7 of REACT-1 commenced swab-collection on 13th November 2020. A prior interim report included data from 13th to 24th November 2020 for 105,122 participants. Here, we report data for the entire round with swab results obtained up to 3rd December 2020.ResultsBetween 13th November and 3rd December (round 7) there were 1,299 positive swabs out of 168,181 giving a weighted prevalence of 0.94% (95% CI 0.87%, 1.01%) or 94 per 10,000 people infected in the community in England. This compares with a prevalence of 1.30% (1.21%, 1.39%) from 16th October to 2nd November 2020 (round 6), a decline of 28%. Prevalence during the latter half of round 7 was 0.91% (95% CI, 0.81%, 1.03%) compared with 0.96% (0.87%, 1.05%) in the first half. The national R number in round 7 was estimated at 0.96 (0.88, 1.03) with a decline in prevalence observed during the first half of this period no longer apparent during the second half at the end of lockdown. During round 7 there was a marked fall in prevalence in West Midlands, a levelling off in some regions and a rise in London. R numbers at regional level ranged from 0.60 (0.41, 0.80) in West Midlands up to 1.27 (1.04, 1.54) in London, where prevalence was highest in the east and south-east of the city. Nationally, between 13th November and 3rd December, the highest prevalence was in school-aged children especially at ages 13-17 years at 2.04% (1.69%, 2.46%), or approximately 1 in 50.ConclusionBetween the previous round and round 7 (during lockdown), there was a fall in prevalence of SARS-C
  • Journal article
    Yan AWC, Zhou J, Beauchemin CAA, Russell CA, Barclay WS, Riley Set al., 2020,

    Quantifying mechanistic traits of influenza viral dynamics using in vitro data.

    , Epidemics: the journal of infectious disease dynamics, Vol: 33, Pages: 1-10, ISSN: 1755-4365

    When analysing in vitro data, growth kinetics of influenza virus strains are often compared by computing their growth rates, which are sometimes used as proxies for fitness. However, analogous to mathematical models for epidemics, the growth rate can be defined as a function of mechanistic traits: the basic reproduction number (the average number of cells each infected cell infects) and the mean generation time (the average length of a replication cycle). Fitting a model to previously published and newly generated data from experiments in human lung cells, we compared estimates of growth rate, reproduction number and generation time for six influenza A strains. Of four strains in previously published data, A/Canada/RV733/2003 (seasonal H1N1) had the lowest basic reproduction number, followed by A/Mexico/INDRE4487/2009 (pandemic H1N1), then A/Indonesia/05/2005 (spill-over H5N1) and A/Anhui/1/2013 (spill-over H7N9). This ordering of strains was preserved for both generation time and growth rate, suggesting a positive biological correlation between these quantities which have not been previously observed. We further investigated these potential correlations using data from reassortant viruses with different internal proteins (from A/England/195/2009 (pandemic H1N1) and A/Turkey/05/2005 (H5N1)), and the same surface proteins (from A/Puerto Rico/8/34 (lab-adapted H1N1)). Similar correlations between traits were observed for these viruses, confirming our initial findings and suggesting that these patterns were related to the degree of human adaptation of internal genes. Also, the model predicted that strains with a smaller basic reproduction number, shorter generation time and slower growth rate underwent more replication cycles by the time of peak viral load, potentially accumulating mutations more quickly. These results illustrate the utility of mathematical models in inferring traits driving observed differences in in vitro growth of influenza strains.
  • Journal article
    Neil D, Moran L, Horsfield C, Curtis E, Swann O, Barclay W, Hanley B, Hollinshead M, Roufosse Cet al., 2020,

    Ultrastructure of cell trafficking pathways and coronavirus: how to recognise the wolf amongst the sheep

    , JOURNAL OF PATHOLOGY, Vol: 252, Pages: 346-357, ISSN: 0022-3417
  • Journal article
    Carrique L, Fan H, Walker AP, Keown JR, Sharps J, Staller E, Barclay WS, Fodor E, Grimes JMet al., 2020,

    Host ANP32A mediates the assembly of the influenza virus replicase

    , Nature, Vol: 587, Pages: 638-643, ISSN: 0028-0836

    Aquatic birds represent a vast reservoir from which new pandemic influenza A viruses can emerge1. Influenza viruses contain a negative-sense segmented RNA genome that is transcribed and replicated by the viral heterotrimeric RNA polymerase (FluPol) in the context of viral ribonucleoprotein complexes2,3. RNA polymerases of avian influenza A viruses (FluPolA) replicate viral RNA inefficiently in human cells because of species-specific differences in acidic nuclear phosphoprotein 32 (ANP32), a family of essential host proteins for FluPol activity4. Host-adaptive mutations, particularly a glutamic-acid-to-lysine mutation at amino acid residue 627 (E627K) in the 627 domain of the PB2 subunit, enable avian FluPolA to overcome this restriction and efficiently replicate viral RNA in the presence of human ANP32 proteins. However, the molecular mechanisms of genome replication and the interplay with ANP32 proteins remain largely unknown. Here we report cryo-electron microscopy structures of influenza C virus polymerase (FluPolC) in complex with human and chicken ANP32A. In both structures, two FluPolC molecules form an asymmetric dimer bridged by the N-terminal leucine-rich repeat domain of ANP32A. The C-terminal low-complexity acidic region of ANP32A inserts between the two juxtaposed PB2 627 domains of the asymmetric FluPolA dimer, suggesting a mechanism for how the adaptive PB2(E627K) mutation enables the replication of viral RNA in mammalian hosts. We propose that this complex represents a replication platform for the viral RNA genome, in which one of the FluPol molecules acts as a replicase while the other initiates the assembly of the nascent replication product into a viral ribonucleoprotein complex.
  • Journal article
    Ahmetaj-Shala B, Peacock TP, Baillon L, Swann OC, Gashaw H, Barclay WS, Mitchell JAet al., 2020,

    Resistance of endothelial cells to SARS-CoV-2 infection <i>in vitro</i>

    <jats:title>Abstract</jats:title><jats:sec><jats:title>Rationale</jats:title><jats:p>The secondary thrombotic/vascular clinical syndrome of COVID-19 suggests that SARS-CoV-2 infects not only respiratory epithelium but also the endothelium activating thrombotic pathways, disrupting barrier function and allowing access of the virus to other organs of the body. However, a direct test of susceptibility to SARS-CoV-2 of authentic endothelial cell lines has not been performed.</jats:p></jats:sec><jats:sec><jats:title>Objective</jats:title><jats:p>To determine infectibility of primary endothelial cell lines with live SARS-CoV-2 and pseudoviruses expressing SARS-CoV-2 spike protein.</jats:p></jats:sec><jats:sec><jats:title>Methods and Results</jats:title><jats:p>Expression of ACE2 and BSG pathways genes was determined in three types of endothelial cells; blood outgrowth, lung microvascular and aortic endothelial cells. For comparison nasal epithelial cells, Vero E6 cells (primate kidney fibroblast cell line) and HEK 293T cells (human embryonic kidney cells) transfected with either ACE2 or BSG were used as controls. Endothelial and Vero E6 cells were treated with live SARS-CoV-2 virus for 1 hour and imaged at 24 and 72 hours post infection. Pseudoviruses containing SARS-CoV-2, Ebola and Vesicular Stomatis Virus glycoproteins were generated and added to endothelial cells and HEK 239Ts for 2 hours and infection measured using luminescence at 48 hours post infection. Compared to nasal epithelial cells, endothelial cells expressed low or undetectable levels of ACE2 and TMPRSS2 but comparable levels of BSG, PPIA and PPIB. Endothelial cells showed no susceptibility to live SARS-CoV-2 or SARS-CoV-2 pseudovirus (but showed susceptibility to Ebola and Vesicular Stomatitis Virus). Overexpression of ACE2 but not BSG in HEK 239T cells conferred SARS-CoV-2 pseudovirus entry. Endoth
  • Journal article
    Gibani MM, Toumazou C, Sohbati M, Sahoo R, Karvela M, Hon T-K, De Mateo S, Burdett A, Leung KYF, Barnett J, Orbeladze A, Luan S, Pournias S, Sun J, Flower B, Bedzo-Nutakor J, Amran M, Quinlan R, Skolimowska K, Herrera C, Rowan A, Badhan A, Klaber R, Davies G, Muir D, Randell P, Crook D, Taylor GP, Barclay W, Mughal N, Moore LSP, Jeffery K, Cooke GSet al., 2020,

    Assessing a novel, lab-free, point-of-care test for SARS-CoV-2 (CovidNudge): a diagnostic accuracy study.

    , The Lancet Microbe, Vol: 1, Pages: e300-e307, ISSN: 2666-5247

    Background: Access to rapid diagnosis is key to the control and management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Laboratory RT-PCR testing is the current standard of care but usually requires a centralised laboratory and significant infrastructure. We describe our diagnostic accuracy assessment of a novel, rapid point-of-care real time RT-PCR CovidNudge test, which requires no laboratory handling or sample pre-processing. Methods: Between April and May, 2020, we obtained two nasopharyngeal swab samples from individuals in three hospitals in London and Oxford (UK). Samples were collected from three groups: self-referred health-care workers with suspected COVID-19; patients attending emergency departments with suspected COVID-19; and hospital inpatient admissions with or without suspected COVID-19. For the CovidNudge test, nasopharyngeal swabs were inserted directly into a cartridge which contains all reagents and components required for RT-PCR reactions, including multiple technical replicates of seven SARS-CoV-2 gene targets (rdrp1, rdrp2, e-gene, n-gene, n1, n2 and n3) and human ribonuclease P (RNaseP) as sample adequacy control. Swab samples were tested in parallel using the CovidNudge platform, and with standard laboratory RT-PCR using swabs in viral transport medium for processing in a central laboratory. The primary analysis was to compare the sensitivity and specificity of the point-of-care CovidNudge test with laboratory-based testing. Findings: We obtained 386 paired samples: 280 (73%) from self-referred health-care workers, 15 (4%) from patients in the emergency department, and 91 (23%) hospital inpatient admissions. Of the 386 paired samples, 67 tested positive on the CovidNudge point-of-care platform and 71 with standard laboratory RT-PCR. The overall sensitivity of the point-of-care test compared with laboratory-based testing was 94% (95% CI 86-98) with an overall specificity of 100% (99-100). The sensitivity of the test varied
  • Journal article
    Hanley B, Naresh KN, Roufosse C, Nicholson AG, Weir J, Cooke GS, Thursz M, Manousou P, Corbett R, Goldin R, Al-Sarraj S, Abdolrasouli A, Swann OC, Baillon L, Penn R, Barclay WS, Viola P, Osborn Met al., 2020,

    Histopathological findings and viral tropism in UK patients with severe fatal COVID-19: a post-mortem study

    , The Lancet Microbe, Vol: 1, Pages: e245-e253, ISSN: 2666-5247

    BackgroundSevere COVID-19 has a high mortality rate. Comprehensive pathological descriptions of COVID-19 are scarce and limited in scope. We aimed to describe the histopathological findings and viral tropism in patients who died of severe COVID-19.MethodsIn this case series, patients were considered eligible if they were older than 18 years, with premortem diagnosis of severe acute respiratory syndrome coronavirus 2 infection and COVID-19 listed clinically as the direct cause of death. Between March 1 and April 30, 2020, full post-mortem examinations were done on nine patients with confirmed COVID-19, including sampling of all major organs. A limited autopsy was done on one additional patient. Histochemical and immunohistochemical analyses were done, and histopathological findings were reported by subspecialist pathologists. Viral quantitative RT-PCR analysis was done on tissue samples from a subset of patients.FindingsThe median age at death of our cohort of ten patients was 73 years (IQR 52–79). Thrombotic features were observed in at least one major organ in all full autopsies, predominantly in the lung (eight [89%] of nine patients), heart (five [56%]), and kidney (four [44%]). Diffuse alveolar damage was the most consistent lung finding (all ten patients); however, organisation was noted in patients with a longer clinical course. We documented lymphocyte depletion (particularly CD8-positive T cells) in haematological organs and haemophagocytosis. Evidence of acute tubular injury was noted in all nine patients examined. Major unexpected findings were acute pancreatitis (two [22%] of nine patients), adrenal micro-infarction (three [33%]), pericarditis (two [22%]), disseminated mucormycosis (one [10%] of ten patients), aortic dissection (one [11%] of nine patients), and marantic endocarditis (one [11%]). Viral genomes were detected outside of the respiratory tract in four of five patients. The presence of subgenomic viral RNA transcripts provided evidence of
  • Journal article
    Seekings AH, Howard WA, Nunez A, Slomka MJ, Banyard AC, Hicks D, Ellis RJ, Nunez-Garcia J, Hartgroves LC, Barclay WS, Banks J, Brown IHet al., 2020,

    The Emergence of H7N7 Highly Pathogenic Avian Influenza Virus from Low Pathogenicity Avian Influenza Virus Using an in ovo Embryo Culture Model

    , VIRUSES-BASEL, Vol: 12
  • Journal article
    Atchison C, Pristerà P, Cooper E, Papageorgiou V, Redd R, Piggin M, Flower B, Fontana G, Satkunarajah S, Ashrafian H, Lawrence-Jones A, Naar L, Chigwende J, Gibbard S, Riley S, Darzi A, Elliott P, Ashby D, Barclay W, Cooke GS, Ward Het al., 2020,

    Usability and acceptability of home-based self-testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibodies for population surveillance

    , Clinical Infectious Diseases, Vol: 2020, Pages: 1-10, ISSN: 1058-4838

    BACKGROUND: This study assesses acceptability and usability of home-based self-testing for SARS-CoV-2 antibodies using lateral flow immunoassays (LFIA). METHODS: We carried out public involvement and pilot testing in 315 volunteers to improve usability. Feedback was obtained through online discussions, questionnaires, observations and interviews of people who tried the test at home. This informed the design of a nationally representative survey of adults in England using two LFIAs (LFIA1 and LFIA2) which were sent to 10,600 and 3,800 participants, respectively, who provided further feedback. RESULTS: Public involvement and pilot testing showed high levels of acceptability, but limitations with the usability of kits. Most people reported completing the test; however, they identified difficulties with practical aspects of the kit, particularly the lancet and pipette, a need for clearer instructions and more guidance on interpretation of results. In the national study, 99.3% (8,693/8,754) of LFIA1 and 98.4% (2,911/2,957) of LFIA2 respondents attempted the test and 97.5% and 97.8% of respondents completed it, respectively. Most found the instructions easy to understand, but some reported difficulties using the pipette (LFIA1: 17.7%) and applying the blood drop to the cassette (LFIA2: 31.3%). Most respondents obtained a valid result (LFIA1: 91.5%; LFIA2: 94.4%). Overall there was substantial concordance between participant and clinician interpreted results (kappa: LFIA1 0.72; LFIA2 0.89). CONCLUSION: Impactful public involvement is feasible in a rapid response setting. Home self-testing with LFIAs can be used with a high degree of acceptability and usability by adults, making them a good option for use in seroprevalence surveys.
  • Journal article
    Flower B, Brown JC, Simmons B, Moshe M, Frise R, Penn R, Kugathasan R, Petersen C, Daunt A, Ashby D, Riley S, Atchison C, Taylor GP, Satkunarajah S, Naar L, Klaber R, Badhan A, Rosadas C, Kahn M, Fernandez N, Sureda-Vives M, Cheeseman H, O'Hara J, Fontana G, Pallett SJC, Rayment M, Jones R, Moore LSP, Cherapanov P, Tedder R, McClure M, Ashrafian H, Shattock R, Ward H, Darzi A, Elliott P, Barclay W, Cooke Get al., 2020,

    Clinical and laboratory evaluation of SARS-CoV-2 lateral flow assays for use in a national COVID-19 sero-prevalence survey

    , Thorax, Vol: 75, Pages: 1082-1088, ISSN: 0040-6376

    BackgroundAccurate antibody tests are essential to monitor the SARS-CoV-2 pandemic. Lateral flow immunoassays (LFIAs) can deliver testing at scale. However, reported performance varies, and sensitivity analyses have generally been conducted on serum from hospitalised patients. For use in community testing, evaluation of finger-prick self-tests, in non-hospitalised individuals, is required.MethodsSensitivity analysis was conducted on 276 non-hospitalised participants. All had tested positive for SARS-CoV-2 by RT-PCR and were ≥21d from symptom-onset. In phase I we evaluated five LFIAs in clinic (with finger-prick) and laboratory (with blood and sera) in comparison to a) PCR-confirmed infection and b) presence of SARS-CoV-2 antibodies on two “in-house” ELISAs. Specificity analysis was performed on 500 pre-pandemic sera. In phase II, six additional LFIAs were assessed with serum.Findings95% (95%CI [92.2, 97.3]) of the infected cohort had detectable antibodies on at least one ELISA. LFIA sensitivity was variable, but significantly inferior to ELISA in 8/11 assessed. Of LFIAs assessed in both clinic and laboratory, finger-prick self-test sensitivity varied from 21%-92% vs PCR-confirmed cases and 22%-96% vs composite ELISA positives. Concordance between finger-prick and serum testing was at best moderate (kappa 0.56) and, at worst, slight (kappa 0.13). All LFIAs had high specificity (97.2% - 99.8%).InterpretationLFIA sensitivity and sample concordance is variable, highlighting the importance of evaluations in setting of intended use. This rigorous approach to LFIA evaluation identified a test with high specificity (98.6% (95%CI [97.1, 99.4])), moderate sensitivity (84.4% with fingerprick (95%CI [70.5, 93.5])), and moderate concordance, suitable for seroprevalence surveys.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://www.imperial.ac.uk:80/respub/WEB-INF/jsp/search-t4-html.jsp Request URI: /respub/WEB-INF/jsp/search-t4-html.jsp Query String: id=1017&limit=10&page=2&respub-action=search.html Current Millis: 1713589372171 Current Time: Sat Apr 20 06:02:52 BST 2024