Structure of the Lassa virus glycan shield provides a model for immunological resistance

Lassa virus is an Old World arenavirus endemic to West Africa that causes severe hemorrhagic fever. Vaccine development has focused on the envelope glycoprotein complex (GPC) that extends from the virion envelope. The often inadequate antibody immune response elicited by both vaccine and natural infection has been, in part, attributed to the abundance ofN-linked glycosylation on the GPC. Here, using a virus-like−particle system that presents Lassa virus GPC in a native-like context, we determine the composite population of each of theN-linked glycosylation sites presented on the trimeric GPC spike. Our analysis reveals the presence of underprocessed oligomannose-type glycans, which form punctuated clusters that obscure the proteinous surface of both the GP1 attachment and GP2 fusion glycoprotein subunits of the Lassa virus GPC. These oligomannose clusters are seemingly derived as a result of sterically reduced accessibility to glycan processing enzymes, and limited amino acid diversification around these sites supports their role protecting against the humoral immune response. Combined, our data provide a structure-based blueprint for understanding how glycans render the glycoprotein spikes of Lassa virus and other Old World arenaviruses immunologically resistant targets.

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Vulnerabilities in coronavirus glycan shields despite extensive glycosylation

10.1101/2020.02.20.957472 ◽

2020 ◽

Cited By ~ 9

Author(s):

Yasunori Watanabe ◽

Zachary T. Berndsen ◽

Jayna Raghwani ◽

Gemma E. Seabright ◽

Joel D. Allen ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Fusion Proteins ◽

Vaccine Development ◽

Specific Area ◽

Lassa Virus ◽

Viral Fusion ◽

Humoral Immune ◽

Influenza Hemagglutinin ◽

Viral Fusion Proteins

AbstractSevere acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses (CoVs) are zoonotic pathogens with high fatality rates and pandemic potential. Vaccine development has focussed on the principal target of the neutralizing humoral immune response, the spike (S) glycoprotein, which mediates receptor recognition and membrane fusion. Coronavirus S proteins are extensively glycosylated viral fusion proteins, encoding around 69-87 N-linked glycosylation sites per trimeric spike. Using a multifaceted structural approach, we reveal a specific area of high glycan density on MERS S that results in the formation of under-processed oligomannose-type glycan clusters, which was absent on SARS and HKU1 CoVs. We provide a comparison of the global glycan density of coronavirus spikes with other viral proteins including HIV-1 envelope, Lassa virus glycoprotein complex, and influenza hemagglutinin, where glycosylation plays a known role in shielding immunogenic epitopes. Consistent with the ability of the antibody-mediated immune response to effectively target and neutralize coronaviruses, we demonstrate that the glycans of coronavirus spikes are not able to form an efficacious high-density global shield to thwart the humoral immune response. Overall, our data reveal how differential organisation of viral glycosylation across class I viral fusion proteins influence not only individual glycan compositions but also the immunological pressure across the viral protein surface.

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Characterization of Lassa Virus Cell Entry and Neutralization with Lassa Virus Pseudoparticles

Journal of Virology ◽

10.1128/jvi.01711-08 ◽

2009 ◽

Vol 83 (7) ◽

pp. 3228-3237 ◽

Cited By ~ 34

Author(s):

François-Loic Cosset ◽

Philippe Marianneau ◽

Geraldine Verney ◽

Fabrice Gallais ◽

Noel Tordo ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Neutralizing Antibodies ◽

Cell Attachment ◽

Low Ph ◽

Cell Entry ◽

Lassa Virus ◽

Ph Optimum ◽

Humoral Immune

ABSTRACT The cell entry and humoral immune response of the human pathogen Lassa virus (LV), a biosafety level 4 (BSL4) Old World arenavirus, are not well characterized. LV pseudoparticles (LVpp) are a surrogate model system that has been used to decipher factors and routes involved in LV cell entry under BSL2 conditions. Here, we describe LVpp, which are highly infectious, with titers approaching those obtained with pseudoparticles displaying G protein of vesicular stomatitis virus and their the use for the characterization of LV cell entry and neutralization. Upon cell attachment, LVpp utilize endocytic vesicles for cell entry as described for many pH-dependent viruses. However, the fusion of the LV glycoproteins is activated at unusually low pH values, with optimal fusion occurring between pH 4.5 and 3, a pH range at which fusion characteristics of viral glycoproteins have so far remained largely unexplored. Consistent with a shifted pH optimum for fusion activation, we found wild-type LV and LVpp to display a remarkable resistance to exposure to low pH. Finally, LVpp allow the fast and quantifiable detection of neutralizing antibodies in human and animal sera and will thus facilitate the study of the humoral immune response in LV infections.

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Two Complex, Adenovirus-Based Vaccines That Together Induce Immune Responses to All Four Dengue Virus Serotypes

Clinical and Vaccine Immunology ◽

10.1128/cvi.00330-06 ◽

2006 ◽

Vol 14 (2) ◽

pp. 182-189 ◽

Cited By ~ 32

Author(s):

David H. Holman ◽

Danher Wang ◽

Kanakatte Raviprakash ◽

Nicholas U. Raja ◽

Min Luo ◽

...

Keyword(s):

Immune Responses ◽

Dengue Virus ◽

Vaccine Development ◽

De Novo ◽

Natural Infection ◽

Hemorrhagic Fever ◽

Virus Infections ◽

Dengue Vaccine ◽

Membrane Antigens ◽

Dengue Virus Serotypes

ABSTRACT Dengue virus infections can cause hemorrhagic fever, shock, encephalitis, and even death. Worldwide, approximately 2.5 billion people live in dengue-infested regions with about 100 million new cases each year, although many of these infections are believed to be silent. There are four antigenically distinct serotypes of dengue virus; thus, immunity from one serotype will not cross-protect from infection with the other three. The difficulties that hamper vaccine development include requirements of the natural conformation of the envelope glycoprotein to induce neutralizing immune responses and the necessity of presenting antigens of all four serotypes. Currently, the only way to meet these requirements is to use a mixture of four serotypes of live attenuated dengue viruses, but safety remains a major problem. In this study, we have developed the basis for a tetravalent dengue vaccine using a novel complex adenovirus platform that is capable of expressing multiple antigens de novo. This dengue vaccine is constructed as a pair of vectors that each expresses the premembrane and envelope genes of two different dengue virus serotypes. Upon vaccination, the vaccine expressed high levels of the dengue virus antigens in cells to mimic a natural infection and induced both humoral and cellular immune responses against multiple serotypes of dengue virus in an animal model. Further analyses show the humoral responses were indeed neutralizing against all four serotypes. Our studies demonstrate the concept of mimicking infections to induce immune responses by synthesizing dengue virus membrane antigens de novo and the feasibility of developing an effective tetravalent dengue vaccine by vector-mediated expression of glycoproteins of the four serotypes.

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Site-specific glycan analysis of the SARS-CoV-2 spike

Science ◽

10.1126/science.abb9983 ◽

2020 ◽

pp. eabb9983 ◽

Cited By ~ 133

Author(s):

Yasunori Watanabe ◽

Joel D. Allen ◽

Daniel Wrapp ◽

Jason S. McLellan ◽

Max Crispin

Keyword(s):

Immune Response ◽

Immune Evasion ◽

Vaccine Development ◽

Mass Spectrometric ◽

Cell Entry ◽

Specific Mass ◽

Site Specific ◽

Humoral Immune ◽

Mass Spectrometric Approach ◽

A Site

The emergence of the betacoronavirus, SARS-CoV-2, the causative agent of COVID-19, represents a significant threat to global human health. Vaccine development is focused on the principal target of the humoral immune response, the spike (S) glycoprotein, which mediates cell entry and membrane fusion. SARS-CoV-2 S gene encodes 22 N-linked glycan sequons per protomer, which likely play a role in protein folding and immune evasion. Here, using a site-specific mass spectrometric approach, we reveal the glycan structures on a recombinant SARS-CoV-2 S immunogen. This analysis enables mapping of the glycan-processing states across the trimeric viral spike. We show how SARS-CoV-2 S glycans differ from typical host glycan processing, which may have implications in viral pathobiology and vaccine design.

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The Humoral Immune Response to HCV: Understanding is Key to Vaccine Development

Frontiers in Immunology ◽

10.3389/fimmu.2014.00550 ◽

2014 ◽

Vol 5 ◽

Cited By ~ 42

Author(s):

SiobhÃ¡n B. Cashman ◽

Brian D. Marsden ◽

Lynn B. Dustin

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Vaccine Development ◽

Humoral Immune

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The Humoral Immune Response to Various Domains of Protective Antigen of Bacillus anthracis in Cutaneous Anthrax Cases in India

Defence Science Journal ◽

10.14429/dsj.66.10805 ◽

2016 ◽

Vol 66 (6) ◽

pp. 645 ◽

Cited By ~ 3

Author(s):

Anshul Varshney ◽

Nidhi Puranik ◽

M. Kumar ◽

A.K. Goel

Keyword(s):

Immune Response ◽

Bacillus Anthracis ◽

Humoral Immune Response ◽

Vaccine Development ◽

Protective Antigen ◽

Lethal Factor ◽

Serum Samples ◽

Public Health Importance ◽

Humoral Immune ◽

Cutaneous Anthrax

Anthrax, caused by Bacillus anthracis is known to occur globally since antiquity. Besides being an important biothreat agent, it is an important public health importance pathogen also in countries like India. B. anthracis secretes three distinct toxins, namely protective antigen (PA), lethal factor (LF) and edema factor (EF). PA is the central moiety of the anthrax toxin complex and therefore has been a molecule of choice for vaccine development. PA has four different domains with different functions. In this study, the major domains of PA were cloned and expressed in bacterial system. The purified recombinant proteins were used to determine the humoral immune response by ELISA using 43 human cutaneous anthrax serum samples. The maximum immunoreactivity was observed with the whole PA protein followed by domain 2, 4 and 1. The study corroborated that in addition to full PA, individual domain 2 and 4 can also be good target for vaccine development as well as for serodiagnostic assays for cutaneous anthrax

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Hubungan Respon Imun Humoral dengan Derajat Trombositopenia pada Pasien Demam Berdarah Dengue

Jurnal Ilmu Kedokteran ◽

10.26891/jik.v4i1.2010.36-41 ◽

2017 ◽

Vol 4 (1) ◽

pp. 36

Author(s):

Fatmawati Fatmawati ◽

Chandra Wijaya

Keyword(s):

Immune Response ◽

Dengue Hemorrhagic Fever ◽

Humoral Immune Response ◽

Analytical Study ◽

Dengue Infection ◽

Hemorrhagic Fever ◽

Statistical Test ◽

Cross Sectional ◽

Humoral Immune ◽

Fever Patient

The correlation between humoral immune response with the level of of thrombocytopenia on dengue hemorrhagicfever patient The aim of this study was to know the correlation between humoral immune response with the level of ofthrombocytopenia on dengue hemorrhagic fever patient. This is a cross sectional analytical study on internal inpatientsof AwalBros Pekanbaru Hospital in August-November 2008. Population was all internal inpatients of AwalBros PekanbaruHospital with working diagnosis dengue hemorrhagic fever. There were 4 pattern of anti Dengue antibody : IgG-/IgM,IgG-/IgM+, IgG+/IgM-, IgG+/IgM+. Most of patients with IgG+/IgM+ and have secondary dengue infection Thoseresult were analyzed by Friedman statistical test. There isn’t a significant correlation between the level ofthrombocytopenia and anti dengue antibody. It show that there wasn’t a direct correlation between them. It could bedue to a cross reaction between anti dengue antibody with thrombocyte (autoantibody).

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Humoral Immune Response to Influenza A(H1N1)pdm2009 in Patients with Natural Infection and in Vaccine Recipients in the 2009 Pandemic

Viral Immunology ◽

10.1089/vim.2014.0010 ◽

2014 ◽

Vol 27 (8) ◽

pp. 368-374 ◽

Cited By ~ 5

Author(s):

Takuji Kumagai ◽

Tetsuo Nakayama ◽

Yoshinobu Okuno ◽

Tetsuo Kase ◽

Naoko Nishimura ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Influenza A ◽

Natural Infection ◽

Humoral Immune ◽

Influenza A H1n1

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Generation and Characterization of Human Monoclonal scFv Antibodies against Helicobacter pylori Antigens

Infection and Immunity ◽

10.1128/iai.70.8.4158-4164.2002 ◽

2002 ◽

Vol 70 (8) ◽

pp. 4158-4164 ◽

Cited By ~ 17

Author(s):

Nicole Reiche ◽

Andreas Jung ◽

Thomas Brabletz ◽

Tanja Vater ◽

Thomas Kirchner ◽

...

Keyword(s):

Immune Response ◽

Helicobacter Pylori ◽

Phage Display ◽

Humoral Immune Response ◽

Vaccine Development ◽

Enzyme Linked Immunosorbent Assay ◽

Single Chain ◽

Humoral Immune ◽

Single Chain Fv ◽

H Pylori

ABSTRACT Infection with Helicobacter pylori is chronic despite a vigorous cellular and humoral immune response and causes severe pathology in some patients. In this study, phage display was used as a new approach in order to investigate the role of the host's humoral immune response in the pathogenesis of H. pylori gastritis. Human monoclonal single-chain Fv (scFv) antibody fragments against H. pylori cell lysate and the H. pylori urease were isolated from an immune phage display library, constructed from peripheral blood lymphocytes of an H. pylori-infected patient. After affinity selection, 23% of the clones tested showed binding activity against a lysate of the H. pylori Sydney strain in enzyme-linked immunosorbent assay (ELISA) and 9% bound the H. pylori urease. Further characterization by PCR-fingerprint analysis and sequencing revealed that two closely related H. pylori binders and one antiurease scFv could be isolated. The selected scFvs were highly specific as analyzed by ELISA and immunoblots using various bacterial lysates and recombinant proteins. Analysis of the humoral immune response following H. pylori infection using human monoclonal antibodies might contribute to a better understanding of the pathogenesis of the disease. Moreover, using immune phage display libraries, it might be possible for relevant epitopes of H. pylori antigens to be determined, which might be of use for vaccine development.

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