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Open accessPosted ContentDOI: 10.1101/2021.03.01.433466

Increased Resistance of SARS-CoV-2 Variant P.1 to Antibody Neutralization

02 Mar 2021-bioRxiv (Cold Spring Harbor Laboratory)-
Abstract: The relative resistance of SARS-CoV-2 variants B.1.1.7 and B.1.351 to antibody neutralization has been described recently. We now report that another emergent variant from Brazil, P.1, is not only refractory to multiple neutralizing monoclonal antibodies, but also more resistant to neutralization by convalescent plasma (3.4 fold) and vaccinee sera (3.8-4.8 fold). The cryo-electron microscopy structure of a soluble prefusion-stabilized spike reveals the P.1 trimer to adopt exclusively a conformation in which one of the receptor-binding domains is in the "up" position, with the functional impact of mutations appearing to arise from local changes instead of global conformational alterations. The P.1 variant threatens current antibody therapies but less so the protective efficacy of our vaccines.

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Topics: Neutralization (53%)

39 results found

Open accessPosted ContentDOI: 10.1101/2021.01.18.427166
19 Jan 2021-bioRxiv
Abstract: SARS-CoV-2 501Y.V2 (B.1.351), a novel lineage of coronavirus causing COVID-19, contains substitutions in two immunodominant domains of the spike protein. Here, we show that pseudovirus expressing 501Y.V2 spike protein completely escapes three classes of therapeutically relevant antibodies. This pseudovirus also exhibits substantial to complete escape from neutralization, but not binding, by convalescent plasma. These data highlight the prospect of reinfection with antigenically distinct variants and foreshadows reduced efficacy of spike-based vaccines.

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Topics: Coronavirus (50%)

83 Citations

Open accessPosted ContentDOI: 10.1101/2021.02.05.21251182
08 Feb 2021-medRxiv
Abstract: Emerging SARS-CoV-2 variants have raised concerns about resistance to neutralizing antibodies elicited by previous infection or vaccination We examined whether sera from recovered and naive donors collected prior to, and following immunizations with existing mRNA vaccines, could neutralize the Wuhan-Hu-1 and B1351 variants Pre-vaccination sera from recovered donors neutralized Wuhan-Hu-1 and sporadically neutralized B1351, but a single immunization boosted neutralizing titers against all variants and SARS-CoV-1 by up to 1000-fold Neutralization was due to antibodies targeting the receptor binding domain and was not boosted by a second immunization Immunization of naive donors also elicited cross-neutralizing responses, but at lower titers Our study highlights the importance of vaccinating both uninfected and previously infected persons to elicit cross-variant neutralizing antibodies

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Topics: Immunization (56%)

50 Citations

Open accessPosted ContentDOI: 10.1101/2021.06.15.21258542
Peter Horby1, M Mafham1, Leon Peto1, Mark Campbell1  +30 moreInstitutions (16)
16 Jun 2021-medRxiv
Abstract: BackgroundREGEN-COV is a combination of 2 monoclonal antibodies (casirivimab and imdevimab) that bind to two different sites on the receptor binding domain of the SARS-CoV-2 spike protein. We aimed to evaluate the efficacy and safety of REGEN-COV in patients admitted to hospital with COVID-19. MethodsIn this randomised, controlled, open-label platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting patients were randomly allocated (1:1) to either usual standard of care alone (usual care group) or usual care plus a single dose of REGEN-COV 8g (casirivimab 4g and imdevimab 4g) by intravenous infusion (REGEN-COV group). The primary outcome was 28-day mortality assessed first among patients without detectable antibodies to SARS-CoV-2 at randomisation (seronegative) and then in the overall population. The trial is registered with ISRCTN (50189673) and (NCT04381936). FindingsBetween 18 September 2020 and 22 May 2021, 9785 patients were randomly allocated to receive usual care plus REGEN-COV or usual care alone, including 3153 (32%) seronegative patients, 5272 (54%) seropositive patients and 1360 (14%) patients with unknown baseline antibody status. In the primary efficacy population of seronegative patients, 396 (24%) of 1633 patients allocated to REGEN-COV and 451 (30%) of 1520 patients allocated to usual care died within 28 days (rate ratio 0{middle dot}80; 95% CI 0{middle dot}70-0{middle dot}91; p=0{middle dot}0010). In an analysis involving all randomised patients (regardless of baseline antibody status), 944 (20%) of 4839 patients allocated to REGEN-COV and 1026 (21%) of 4946 patients allocated to usual care died within 28 days (rate ratio 0{middle dot}94; 95% CI 0{middle dot}86-1{middle dot}03; p=0{middle dot}17). The proportional effect of REGEN-COV on mortality differed significantly between seropositive and seronegative patients (p value for heterogeneity = 0{middle dot}001). InterpretationIn patients hospitalised with COVID-19, the monoclonal antibody combination of casirivimab and imdevimab (REGEN-COV) reduced 28-day mortality among patients who were seronegative at baseline. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056).

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Topics: Population (51%)

41 Citations

Open accessJournal ArticleDOI: 10.1073/PNAS.2103154118
Abstract: To investigate the evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the immune population, we coincupi bated the authentic virus with a highly neutralizing plasma from a COVID-19 convalescent patient. The plasma fully neutralized the virus for seven passages, but, after 45 d, the deletion of F140 in the spike N-terminal domain (NTD) N3 loop led to partial breakthrough. At day 73, an E484K substitution in the receptor-binding domain (RBD) occurred, followed, at day 80, by an insertion in the NTD N5 loop containing a new glycan sequon, which generated a variant completely resistant to plasma neutralization. Computational modeling predicts that the deletion and insertion in loops N3 and N5 prevent binding of neutralizing antibodies. The recent emergence in the United Kingdom, South Africa, Brazil, and Japan of natural variants with similar changes suggests that SARS-CoV-2 has the potential to escape an effective immune response and that vaccines and antibodies able to control emerging variants should be developed.

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Topics: Population (52%)

32 Citations

Open accessPosted ContentDOI: 10.1101/2021.03.12.435194
Wanwisa Dejnirattisai1, D. Zhou1, Piyada Supasa1, Chang Liu1  +50 moreInstitutions (6)
15 Mar 2021-bioRxiv
Abstract: Summary Terminating the SARS-CoV-2 pandemic relies upon pan-global vaccination. Current vaccines elicit neutralizing antibody responses to the virus spike derived from early isolates. However, new strains have emerged with multiple mutations: P.1 from Brazil, B.1.351 from South Africa and B.1.1.7 from the UK (12, 10 and 9 changes in the spike respectively). All have mutations in the ACE2 binding site with P.1 and B.1.351 having a virtually identical triplet: E484K, K417N/T and N501Y, which we show confer similar increased affinity for ACE2. We show that, surprisingly, P.1 is significantly less resistant to naturally acquired or vaccine induced antibody responses than B.1.351 suggesting that changes outside the RBD impact neutralisation. Monoclonal antibody 222 neutralises all three variants despite interacting with two of the ACE2 binding site mutations, we explain this through structural analysis and use the 222 light chain to largely restore neutralization potency to a major class of public antibodies.

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Topics: Neutralizing antibody (57%), Antibody (51%)

27 Citations


30 results found

Open accessJournal ArticleDOI: 10.1107/S0907444904019158
Paul Emsley1, Kevin Cowtan1Institutions (1)
Abstract: CCP4mg is a project that aims to provide a general-purpose tool for structural biologists, providing tools for X-ray structure solution, structure comparison and analysis, and publication-quality graphics. The map-fitting tools are available as a stand-alone package, distributed as `Coot'.

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Topics: Computer graphics (56%), Molecular graphics (56%), Enzyme structure (55%) ... read more

24,547 Citations

Open accessJournal ArticleDOI: 10.1056/NEJMOA2034577
Abstract: Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the resulting coronavirus disease 2019 (Covid-19) have afflicted tens of millions of people in a world...

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4,222 Citations

Open accessJournal ArticleDOI: 10.1016/J.CELL.2020.06.043
20 Aug 2020-Cell
Abstract: A SARS-CoV-2 variant carrying the Spike protein amino acid change D614G has become the most prevalent form in the global pandemic. Dynamic tracking of variant frequencies revealed a recurrent pattern of G614 increase at multiple geographic levels: national, regional, and municipal. The shift occurred even in local epidemics where the original D614 form was well established prior to introduction of the G614 variant. The consistency of this pattern was highly statistically significant, suggesting that the G614 variant may have a fitness advantage. We found that the G614 variant grows to a higher titer as pseudotyped virions. In infected individuals, G614 is associated with lower RT-PCR cycle thresholds, suggestive of higher upper respiratory tract viral loads, but not with increased disease severity. These findings illuminate changes important for a mechanistic understanding of the virus and support continuing surveillance of Spike mutations to aid with development of immunological interventions.

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2,165 Citations

Journal ArticleDOI: 10.1038/NMETH.4169
01 Mar 2017-Nature Methods
Abstract: Single-particle electron cryomicroscopy (cryo-EM) is a powerful method for determining the structures of biological macromolecules. With automated microscopes, cryo-EM data can often be obtained in a few days. However, processing cryo-EM image data to reveal heterogeneity in the protein structure and to refine 3D maps to high resolution frequently becomes a severe bottleneck, requiring expert intervention, prior structural knowledge, and weeks of calculations on expensive computer clusters. Here we show that stochastic gradient descent (SGD) and branch-and-bound maximum likelihood optimization algorithms permit the major steps in cryo-EM structure determination to be performed in hours or minutes on an inexpensive desktop computer. Furthermore, SGD with Bayesian marginalization allows ab initio 3D classification, enabling automated analysis and discovery of unexpected structures without bias from a reference map. These algorithms are combined in a user-friendly computer program named cryoSPARC (

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2,105 Citations

Open accessJournal ArticleDOI: 10.1002/PRO.3235
01 Jan 2018-Protein Science
Abstract: UCSF ChimeraX is next-generation software for the visualization and analysis of molecular structures, density maps, 3D microscopy, and associated data. It addresses challenges in the size, scope, and disparate types of data attendant with cutting-edge experimental methods, while providing advanced options for high-quality rendering (interactive ambient occlusion, reliable molecular surface calculations, etc.) and professional approaches to software design and distribution. This article highlights some specific advances in the areas of visualization and usability, performance, and extensibility. ChimeraX is free for noncommercial use and is available from for Windows, Mac, and Linux.

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Topics: Biological data visualization (60%), Information visualization (58%), Visualization (56%) ... read more

1,562 Citations

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