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1.
Pak J Pharm Sci ; 34(1(Supplementary)): 345-352, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275860

RESUMO

SARS-CoV-2, a new world coronavirus belonging to class Nidovirales of Coronaviridae family causes COVID-19 infection which is the leading cause of death worldwide. Currently there are no approved drugs and vaccines available for the prevention of COVID-19 infection, although couples of immunizations are being tested in clinical trials. However, the present efforts are focused on computational vaccination technique for evaluating candidates to design multi-epitope-based vaccine against pathogenic mechanism of novel SARS-COV-2. Based on recent published evidence, we recognized spike glycoprotein and envelope small membrane protein are the potential targets to combat the pathogenic mechanism of SARS-CoV-2. Similarly, in the present study we identified epitope of both B and T cell associated with these proteins. Extremely antigenic, conserve, immunogenic and nontoxic epitope of B and T cell of Spike protein are WPWYVWLGFI, SRVKNLNSSEGVPDLLV whereas the CWCARPTCIK and YCCNIVNVSL are associated with envelope small membrane protein were selected as potential candidate for vaccine designing. These epitopes show virtuous interaction with HLAA0201 during molecular docking analysis. Under simulation protocol the predicted vaccine candidates show stability. Collectively, this work provides novel potential candidates for epitope-based vaccine designing against COVID-19 infection.


Assuntos
Vacinas contra COVID-19/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Biologia Computacional/métodos , Epitopos de Linfócito B/química , Epitopos de Linfócito T/química , Antígeno HLA-A2/química , Antígeno HLA-A2/imunologia , Humanos , Imunogenicidade da Vacina , Modelos Moleculares , Simulação de Acoplamento Molecular , SARS-CoV-2/química , Termodinâmica , Proteínas Virais/imunologia
2.
PLoS Biol ; 19(6): e3001265, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34143766

RESUMO

The search for potential antibody-based diagnostics, vaccines, and therapeutics for pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has focused almost exclusively on the spike (S) and nucleocapsid (N) proteins. Coronavirus membrane (M), ORF3a, and ORF8 proteins are humoral immunogens in other coronaviruses (CoVs) but remain largely uninvestigated for SARS-CoV-2. Here, we use ultradense peptide microarray mapping to show that SARS-CoV-2 infection induces robust antibody responses to epitopes throughout the SARS-CoV-2 proteome, particularly in M, in which 1 epitope achieved excellent diagnostic accuracy. We map 79 B cell epitopes throughout the SARS-CoV-2 proteome and demonstrate that antibodies that develop in response to SARS-CoV-2 infection bind homologous peptide sequences in the 6 other known human CoVs. We also confirm reactivity against 4 of our top-ranking epitopes by enzyme-linked immunosorbent assay (ELISA). Illness severity correlated with increased reactivity to 9 SARS-CoV-2 epitopes in S, M, N, and ORF3a in our population. Our results demonstrate previously unknown, highly reactive B cell epitopes throughout the full proteome of SARS-CoV-2 and other CoV proteins.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Proteínas Virais/imunologia , Anticorpos Antivirais/sangue , COVID-19/patologia , Coronavirus/imunologia , Reações Cruzadas , Epitopos de Linfócito B , Humanos , Epitopos Imunodominantes , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Proteoma/imunologia , Índice de Gravidade de Doença
3.
J Biomed Sci ; 28(1): 43, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098950

RESUMO

BACKGROUND: Coronavirus disease 19 (COVID-19) first appeared in the city of Wuhan, in the Hubei province of China. Since its emergence, the COVID-19-causing virus, SARS-CoV-2, has been rapidly transmitted around the globe, overwhelming the medical care systems in many countries and leading to more than 3.3 million deaths. Identification of immunological epitopes on the virus would be highly useful for the development of diagnostic tools and vaccines that will be critical to limiting further spread of COVID-19. METHODS: To find disease-specific B-cell epitopes that correspond to or mimic natural epitopes, we used phage display technology to determine the targets of specific antibodies present in the sera of immune-responsive COVID-19 patients. Enzyme-linked immunosorbent assays were further applied to assess competitive antibody binding and serological detection. VaxiJen, BepiPred-2.0 and DiscoTope 2.0 were utilized for B-cell epitope prediction. PyMOL was used for protein structural analysis. RESULTS: 36 enriched peptides were identified by biopanning with antibodies from two COVID-19 patients; the peptides 4 motifs with consensus residues corresponding to two potential B-cell epitopes on SARS-CoV-2 viral proteins. The putative epitopes and hit peptides were then synthesized for validation by competitive antibody binding and serological detection. CONCLUSIONS: The identified B-cell epitopes on SARS-CoV-2 may aid investigations into COVID-19 pathogenesis and facilitate the development of epitope-based serological diagnostics and vaccines.


Assuntos
COVID-19 , Epitopos de Linfócito B , Biblioteca de Peptídeos , SARS-CoV-2 , Proteínas Virais , COVID-19/genética , COVID-19/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia
4.
Cell Rep ; 35(7): 109126, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33974846

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evades most innate immune responses but may still be vulnerable to some. Here, we systematically analyze the impact of SARS-CoV-2 proteins on interferon (IFN) responses and autophagy. We show that SARS-CoV-2 proteins synergize to counteract anti-viral immune responses. For example, Nsp14 targets the type I IFN receptor for lysosomal degradation, ORF3a prevents fusion of autophagosomes and lysosomes, and ORF7a interferes with autophagosome acidification. Most activities are evolutionarily conserved. However, SARS-CoV-2 Nsp15 antagonizes IFN signaling less efficiently than the orthologs of closely related RaTG13-CoV and SARS-CoV-1. Overall, SARS-CoV-2 proteins counteract autophagy and type I IFN more efficiently than type II or III IFN signaling, and infection experiments confirm potent inhibition by IFN-γ and -λ1. Our results define the repertoire and selected mechanisms of SARS-CoV-2 innate immune antagonists but also reveal vulnerability to type II and III IFN that may help to develop safe and effective anti-viral approaches.


Assuntos
COVID-19/virologia , SARS-CoV-2/imunologia , Proteínas Virais/imunologia , Animais , Antivirais/farmacologia , Autofagossomos/imunologia , Autofagia/imunologia , COVID-19/imunologia , Linhagem Celular , Chlorocebus aethiops , Exorribonucleases/imunologia , Células HEK293 , Células HeLa , Humanos , Evasão da Resposta Imune , Imunidade Inata , Interferon Tipo I/metabolismo , Interferons/metabolismo , Receptor de Interferon alfa e beta/antagonistas & inibidores , Receptor de Interferon alfa e beta/imunologia , SARS-CoV-2/patogenicidade , Células Vero , Proteínas não Estruturais Virais/imunologia
5.
Cell Rep ; 35(8): 109164, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33991511

RESUMO

A major goal of current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine efforts is to elicit antibody responses that confer protection. Mapping the epitope targets of the SARS-CoV-2 antibody response is critical for vaccine design, diagnostics, and development of therapeutics. Here, we develop a pan-coronavirus phage display library to map antibody binding sites at high resolution within the complete viral proteomes of all known human-infecting coronaviruses in patients with mild or moderate/severe coronavirus disease 2019 (COVID-19). We find that the majority of immune responses to SARS-CoV-2 are targeted to the spike protein, nucleocapsid, and ORF1ab and include sites of mutation in current variants of concern. Some epitopes are identified in the majority of samples, while others are rare, and we find variation in the number of epitopes targeted between individuals. We find low levels of SARS-CoV-2 cross-reactivity in individuals with no exposure to the virus and significant cross-reactivity with endemic human coronaviruses (CoVs) in convalescent sera from patients with COVID-19.


Assuntos
COVID-19/imunologia , Epitopos/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Proteínas Virais/imunologia , Adulto , Idoso , Anticorpos Antivirais/imunologia , Sítios de Ligação de Anticorpos , COVID-19/virologia , Técnicas de Visualização da Superfície Celular , Coronavirus/imunologia , Reações Cruzadas , Feminino , Células HEK293 , Humanos , Imunidade , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , Poliproteínas/imunologia , Sorologia , Adulto Jovem
6.
Nat Commun ; 12(1): 2633, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976149

RESUMO

Ebola virus (EBOV) glycoprotein (GP) can be recognized by neutralizing antibodies (NAbs) and is the main target for vaccine design. Here, we first investigate the contribution of the stalk and heptad repeat 1-C (HR1C) regions to GP metastability. Specific stalk and HR1C modifications in a mucin-deleted form (GPΔmuc) increase trimer yield, whereas alterations of HR1C exert a more complex effect on thermostability. Crystal structures are determined to validate two rationally designed GPΔmuc trimers in their unliganded state. We then display a modified GPΔmuc trimer on reengineered protein nanoparticles that encapsulate a layer of locking domains (LD) and a cluster of helper T-cell epitopes. In mice and rabbits, GP trimers and nanoparticles elicit cross-ebolavirus NAbs, as well as non-NAbs that enhance pseudovirus infection. Repertoire sequencing reveals quantitative profiles of vaccine-induced B-cell responses. This study demonstrates a promising vaccine strategy for filoviruses, such as EBOV, based on GP stabilization and nanoparticle display.


Assuntos
Vacinas contra Ebola/administração & dosagem , Glicoproteínas/administração & dosagem , Doença pelo Vírus Ebola/terapia , Proteínas Virais/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antígenos Virais/administração & dosagem , Antígenos Virais/genética , Antígenos Virais/imunologia , Antígenos Virais/ultraestrutura , Linfócitos B/imunologia , Cristalografia por Raios X , Modelos Animais de Doenças , Vacinas contra Ebola/genética , Vacinas contra Ebola/imunologia , Ebolavirus/genética , Ebolavirus/imunologia , Epitopos de Linfócito T/administração & dosagem , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/ultraestrutura , Feminino , Glicoproteínas/genética , Glicoproteínas/imunologia , Glicoproteínas/ultraestrutura , Doença pelo Vírus Ebola/sangue , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Camundongos , Nanopartículas/química , Domínios Proteicos/genética , Domínios Proteicos/imunologia , Engenharia de Proteínas , Multimerização Proteica/genética , Multimerização Proteica/imunologia , Estabilidade Proteica , Coelhos , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Proteínas Virais/ultraestrutura
7.
PLoS One ; 16(5): e0252571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34043733

RESUMO

The causative agent of the pandemic identified as SARS-CoV-2 leads to a severe respiratory illness similar to SARS and MERS with fever, cough, and shortness of breath symptoms and severe cases that can often be fatal. In our study, we report our findings based on molecular docking analysis which could be the new effective way for controlling the SARS-CoV-2 virus and additionally, another manipulative possibilities involving the mimicking of immune system as occurred during the bacterial cell recognition system. For this purpose, we performed molecular docking using computational biology techniques on several SARS-CoV-2 proteins that are responsible for its pathogenicity against N-acetyl-D-glucosamine. A similar molecular dynamics analysis has been carried out on both SARS-CoV-2 and anti-Staphylococcus aureus neutralizing antibodies to establish the potential of N-acetyl-D-glucosamine which likely induces the immune response against the virus. The results of molecular dynamic analysis have confirmed that SARS-CoV-2 spike receptor-binding domain (PDB: 6M0J), RNA-binding domain of nucleocapsid phosphoprotein (PDB: 6WKP), refusion SARS-CoV-2 S ectodomain trimer (PDB: 6X79), and main protease 3clpro at room temperature (PDB: 7JVZ) could bind with N-acetyl-D-glucosamine that these proteins play an important role in SARS-CoV-2's infection and evade the immune system. Moreover, our molecular docking analysis has supported a strong protein-ligand interaction of N-acetyl-D-glucosamine with these selected proteins. Furthermore, computational analysis against the D614G mutant of the virus has shown that N-acetyl-D-glucosamine affinity and its binding potential were not affected by the mutations occurring in the virus' receptor binding domain. The analysis on the affinity of N-acetyl-D-glucosamine towards human antibodies has shown that it could potentially bind to both SARS-CoV-2 proteins and antibodies based on our predictive modelling work. Our results confirmed that N-acetyl-D-glucosamine holds the potential to inhibit several SARS-CoV-2 proteins as well as induce an immune response against the virus in the host.


Assuntos
Acetilglucosamina/química , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Simulação de Dinâmica Molecular , SARS-CoV-2/química , Proteínas Virais/química , Fatores de Virulência/química , Acetilglucosamina/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Proteínas Virais/imunologia , Fatores de Virulência/imunologia
9.
Emerg Microbes Infect ; 10(1): 1016-1023, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34003073

RESUMO

Given the on-going SARS-CoV-2 pandemic, identification of immunogenic targets against the viral protein will provide crucial advances towards the development of sensitive diagnostic tools and vaccination strategies. Our previous study has found that ORF8 protein of SARS-CoV-2 is highly immunogenic and shows high sensitivity in identifying COVID-19 disease. In this study, by employing overlapping linear peptides, we characterized the IgG immunodominant regions on SARS-CoV-2 ORF8 protein that are seropositive in the sera from SARS-CoV-2-infected patients. The major immunogenic epitopes are localized at (1) N-termini alpha helix, (2) the resides spanning beta 2 and 3 sheets, and (3) the loop between beta 4 and 5 sheets. Additionally, hamster model infected by SARS-CoV-2 further validates the seropositivity of the linear epitopes in vivo, demonstrating a potential application of the linear peptide-based immunization strategy. Taken together, identification and validation of these B-cell linear epitopes will provide insights into the design of serological diagnostics and peptide-based vaccination approach against this pandemic virus of high priority.


Assuntos
COVID-19/imunologia , Epitopos de Linfócito B , SARS-CoV-2/imunologia , Proteínas Virais/química , Animais , Anticorpos Antivirais , Cricetinae , Humanos , Epitopos Imunodominantes , Mesocricetus , Modelos Moleculares , Conformação Proteica , Proteínas Virais/imunologia
10.
Nat Commun ; 12(1): 2593, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972535

RESUMO

The COVID-19 pandemic caused by SARS-CoV-2 is a continuous challenge worldwide, and there is an urgent need to map the landscape of immunogenic and immunodominant epitopes recognized by CD8+ T cells. Here, we analyze samples from 31 patients with COVID-19 for CD8+ T cell recognition of 500 peptide-HLA class I complexes, restricted by 10 common HLA alleles. We identify 18 CD8+ T cell recognized SARS-CoV-2 epitopes, including an epitope with immunodominant features derived from ORF1ab and restricted by HLA-A*01:01. In-depth characterization of SARS-CoV-2-specific CD8+ T cell responses of patients with acute critical and severe disease reveals high expression of NKG2A, lack of cytokine production and a gene expression profile inhibiting T cell re-activation and migration while sustaining survival. SARS-CoV-2-specific CD8+ T cell responses are detectable up to 5 months after recovery from critical and severe disease, and these responses convert from dysfunctional effector to functional memory CD8+ T cells during convalescence.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Epitopos Imunodominantes/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Linfócitos T CD8-Positivos/patologia , COVID-19/patologia , Epitopos de Linfócito T/imunologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Epitopos Imunodominantes/química , Memória Imunológica , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Poliproteínas/imunologia , Proteínas Virais/imunologia
11.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34021074

RESUMO

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic and has claimed over 2 million lives worldwide. Although the genetic sequences of SARS-CoV and SARS-CoV-2 have high homology, the clinical and pathological characteristics of COVID-19 differ significantly from those of SARS. How and whether SARS-CoV-2 evades (cellular) immune surveillance requires further elucidation. In this study, we show that SARS-CoV-2 infection leads to major histocompability complex class Ι (MHC-Ι) down-regulation both in vitro and in vivo. The viral protein encoded by open reading frame 8 (ORF8) of SARS-CoV-2, which shares the least homology with SARS-CoV among all viral proteins, directly interacts with MHC-Ι molecules and mediates their down-regulation. In ORF8-expressing cells, MHC-Ι molecules are selectively targeted for lysosomal degradation via autophagy. Thus, SARS-CoV-2-infected cells are much less sensitive to lysis by cytotoxic T lymphocytes. Because ORF8 protein impairs the antigen presentation system, inhibition of ORF8 could be a strategy to improve immune surveillance.


Assuntos
Apresentação do Antígeno , COVID-19/imunologia , Regulação para Baixo/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Evasão da Resposta Imune , SARS-CoV-2/imunologia , Proteínas Virais/imunologia , Animais , Autofagia/genética , Autofagia/imunologia , COVID-19/genética , Chlorocebus aethiops , Células HEK293 , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Lisossomos/genética , Lisossomos/imunologia , Lisossomos/virologia , Camundongos , Camundongos Transgênicos , SARS-CoV-2/genética , Células Vero , Proteínas Virais/genética
12.
Nat Immunol ; 22(7): 820-828, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33976430

RESUMO

Efficient immune responses against viral infection are determined by sufficient activation of nucleic acid sensor-mediated innate immunity1,2. Coronavirus disease 2019, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains an ongoing global pandemic. It is an urgent challenge to clarify the innate recognition mechanism to control this virus. Here we show that retinoic acid-inducible gene-I (RIG-I) sufficiently restrains SARS-CoV-2 replication in human lung cells in a type I/III interferon (IFN)-independent manner. RIG-I recognizes the 3' untranslated region of the SARS-CoV-2 RNA genome via the helicase domains, but not the C-terminal domain. This new mode of RIG-I recognition does not stimulate its ATPase, thereby aborting the activation of the conventional mitochondrial antiviral-signaling protein-dependent pathways, which is in accordance with lack of cytokine induction. Nevertheless, the interaction of RIG-I with the viral genome directly abrogates viral RNA-dependent RNA polymerase mediation of the first step of replication. Consistently, genetic ablation of RIG-I allows lung cells to produce viral particles that expressed the viral spike protein. By contrast, the anti-SARS-CoV-2 activity was restored by all-trans retinoic acid treatment through upregulation of RIG-I protein expression in primary lung cells derived from patients with chronic obstructive pulmonary disease. Thus, our findings demonstrate the distinctive role of RIG-I as a restraining factor in the early phase of SARS-CoV-2 infection in human lung cells.


Assuntos
COVID-19/imunologia , Proteína DEAD-box 58/imunologia , Pulmão/imunologia , Receptores Imunológicos/imunologia , SARS-CoV-2/imunologia , Células A549 , Animais , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Cães , Células HEK293 , Humanos , Interferon Tipo I/imunologia , Interferons/imunologia , Pulmão/virologia , Células Madin Darby de Rim Canino , Doença Pulmonar Obstrutiva Crônica/imunologia , RNA Polimerase Dependente de RNA/imunologia , Células Sf9 , Transdução de Sinais/imunologia , Células Vero , Proteínas Virais/imunologia
13.
J Genet Genomics ; 48(2): 107-114, 2021 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-34006471

RESUMO

The ongoing COVID-19 pandemic and its unprecedented global societal and economic disruptive impact highlight the urgent need for safe and effective vaccines. Taking substantial advantages of versatility and rapid development, two mRNA vaccines against COVID-19 have completed late-stage clinical assessment at an unprecedented speed and reported positive results. In this review, we outline keynotes in mRNA vaccine development, discuss recently published data on COVID-19 mRNA vaccine candidates, focusing on those in clinical trials and analyze future potential challenges.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , RNA Mensageiro/imunologia , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Sítios de Ligação/genética , Sítios de Ligação/imunologia , COVID-19/epidemiologia , COVID-19/virologia , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/uso terapêutico , Desenvolvimento de Medicamentos , Humanos , Pandemias/prevenção & controle , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Vacinas Sintéticas/genética , Proteínas Virais/genética , Proteínas Virais/imunologia , Proteínas Virais/metabolismo
14.
Cell Rep ; 35(9): 109197, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34043946

RESUMO

Over 950,000 whole-genome sequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been determined for viruses isolated from around the world. These sequences are critical for understanding the spread and evolution of SARS-CoV-2. Using global phylogenomics, we show that mutations frequently occur in the C-terminal end of ORF7a. We isolate one of these mutant viruses from a patient sample and use viral challenge experiments to link this isolate (ORF7aΔ115) to a growth defect. ORF7a is implicated in immune modulation, and we show that the C-terminal truncation negates anti-immune activities of the protein, which results in elevated type I interferon response to the viral infection. Collectively, this work indicates that ORF7a mutations occur frequently, and that these changes affect viral mechanisms responsible for suppressing the immune response.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Imunidade , SARS-CoV-2/genética , Proteínas Virais/genética , Proteínas Virais/imunologia , Animais , Chlorocebus aethiops , Genoma Viral , Células HEK293 , Humanos , Interferon Tipo I/imunologia , Mutação , Filogenia , SARS-CoV-2/patogenicidade , Células Vero , Proteínas Virais Reguladoras e Acessórias/genética
15.
Viruses ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925069

RESUMO

One of the most effective strategies for eliminating new and emerging infectious diseases is effective immunization. The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) warrants the need for a maximum coverage vaccine. Moreover, mutations that arise within the virus have a significant impact on the vaccination strategy. Here, we built a comprehensive in silico workflow pipeline to identify B-cell- and T-cell-stimulating antigens of SARS-CoV-2 viral proteins. Our in silico reverse vaccinology (RV) approach consisted of two parts: (1) analysis of the selected viral proteins based on annotated cellular location, antigenicity, allele coverage, epitope density, and mutation density and (2) analysis of the various aspects of the epitopes, including antigenicity, allele coverage, IFN-γ induction, toxicity, host homology, and site mutational density. After performing a mutation analysis based on the contemporary mutational amino acid substitutions observed in the viral variants, 13 potential epitopes were selected as subunit vaccine candidates. Despite mutational amino acid substitutions, most epitope sequences were predicted to retain immunogenicity without toxicity and host homology. Our RV approach using an in silico pipeline may potentially reduce the time required for effective vaccine development and can be applicable for vaccine development for other pathogenic diseases as well.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Antígenos Virais/química , Antígenos Virais/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Humanos , Imunogenicidade da Vacina , Simulação de Acoplamento Molecular , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Subunidades/imunologia , Vacinologia/métodos , Proteínas Virais/genética , Proteínas Virais/imunologia
16.
Sci Rep ; 11(1): 8920, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903660

RESUMO

Immunoassays are a standard diagnostic tool that assesses immunity in severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection. However, immunoassays do not provide information about contaminating antigens or cross-reactions and might exhibit inaccurately high sensitivity and low specificity. We aimed to gain insight into the serological immune response of SARS-CoV-2 patients by immunoblot analysis. We analyzed serum immunoglobulins IgM, -A, and -G directed against SARS-CoV-2 proteins by immunoblot analysis from 12 infected patients. We determined IgG isotype antibodies by commercially available ELISA and assessed the clinical parameters of inflammation status and kidney and liver injury. Unexpectedly, we found no correlation between the presence of antibodies and the future course of the disease. However, attention should be paid to the parameters CRP, IL-6, and LDH. We found evidence of antibody cross-reactivity, which questions the reliability of results for serum samples that tested negative for anti-SARS-CoV-2 antibodies when assessed by immunoassays. Nevertheless, for the detection of IgG anti-SARS-CoV-2 antibodies, our data suggest that the use of the spike glycoprotein in immunoassays should be sufficient to identify positive patients. Using a combination of the spike glycoprotein and the open reading frame 8 protein could prove to be the best way of detecting anti-SARS-CoV-2 IgM antibodies.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/diagnóstico , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Proteínas Virais/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Especificidade de Anticorpos , COVID-19/imunologia , COVID-19/virologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Nat Commun ; 12(1): 2283, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863907

RESUMO

Narcolepsy type 1 (NT1) is a chronic neurological disorder having a strong association with HLA-DQB1*0602, thereby suggesting an immunological origin. Increased risk of NT1 has been reported among children or adolescents vaccinated with AS03 adjuvant-supplemented pandemic H1N1 influenza A vaccine, Pandemrix. Here we show that pediatric Pandemrix-associated NT1 patients have enhanced T-cell immunity against the viral epitopes, neuraminidase 175-189 (NA175-189) and nucleoprotein 214-228 (NP214-228), but also respond to a NA175-189-mimic, brain self-epitope, protein-O-mannosyltransferase 1 (POMT1675-689). A pathogenic role of influenza virus-specific T-cells and T-cell cross-reactivity in NT1 are supported by the up-regulation of IFN-γ, perforin 1 and granzyme B, and by the converging selection of T-cell receptor TRAV10/TRAJ17 and TRAV10/TRAJ24 clonotypes, in response to stimulation either with peptide NA175-189 or POMT1675-689. Moreover, anti-POMT1 serum autoantibodies are increased in Pandemrix-vaccinated children or adolescents. These results thus identify POMT1 as a potential autoantigen recognized by T- and B-cells in NT1.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Manosiltransferases/imunologia , Narcolepsia/imunologia , Adolescente , Animais , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/imunologia , Linfócitos B/imunologia , Antígenos CD4/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Modelos Animais de Doenças , Epitopos de Linfócito T/imunologia , Feminino , Cadeias beta de HLA-DQ/imunologia , Humanos , Lactente , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Masculino , Camundongos Transgênicos , Narcolepsia/sangue , Narcolepsia/induzido quimicamente , Neuraminidase/imunologia , Linfócitos T/imunologia , Proteínas Virais/imunologia , Adulto Jovem
18.
Front Immunol ; 12: 633769, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912161

RESUMO

The global expansion of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as one of the greatest public health challenges and imposes a great threat to human health. Innate immunity plays vital roles in eliminating viruses through initiating type I interferons (IFNs)-dependent antiviral responses and inducing inflammation. Therefore, optimal activation of innate immunity and balanced type I IFN responses and inflammation are beneficial for efficient elimination of invading viruses. However, SARS-CoV-2 manipulates the host's innate immune system by multiple mechanisms, leading to aberrant type I IFN responses and excessive inflammation. In this review, we will emphasize the recent advances in the understanding of the crosstalk between host innate immunity and SARS-CoV-2 to explain the imbalance between inflammation and type I IFN responses caused by viral infection, and explore potential therapeutic targets for COVID-19.


Assuntos
COVID-19/imunologia , Interferon Tipo I/imunologia , SARS-CoV-2/imunologia , COVID-19/tratamento farmacológico , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Inflamação , Interferon Tipo I/uso terapêutico , Pulmão/imunologia , Transdução de Sinais , Proteínas Virais/imunologia
19.
Arch Insect Biochem Physiol ; 107(2): e21786, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33818830

RESUMO

Cotesia kariyai (Ck) larvae implanted into the body cavity of the Mythimna separata (armyworm) larvae get melanized and encapsulated after adhesion by hemocytes called hyperspread cells (HSCs). The present study showed that HSCs could not adhere to the implanted Ck larvae in armyworm larvae after injection of Ck polydnavirus (CkPDV) + venom (V), thus melanization and encapsulation could not occur. A C-type lectin called Mys-IML of the host armyworm larvae was considered to be involved in the recognition of foreign substances which always expressed in hemocytes. The CkPDV DNA encodes a C-type lectin called Cky811 that has high amino acid homology to Mys-IML. HSCs did not adhere when CkPDV + V was mixed with the hemolymph of armyworm larvae on glass slides and incubated in vitro, but the addition of anti-Cky811 antibody enabled HSCs to adhere. The messenger RNA (mRNA) expression of Mys-IML in armyworm larvae injected with CkPDV + V became undetectable by 6 h. On the contrary, Cky811 mRNA was well expressed in the hemocytes of armyworm larvae injected with CkPDV + V from 0.5 to 6 h. Cky811 protein was also detected in the crude extracts from Ck venom gland + Ck venom reservoir, suggesting that these proteins regulate foreign substance recognition by the armyworm within 0.5 h. These results suggest that CkPDV + V suppresses mRNA expression of Mys-IML, and that Cky811 protein expressed in hemocytes regulates foreign substance recognition of Mys-IML, resulting in inhibition of the downstream reaction steps: HSCs adhesion, melanization, and encapsulation.


Assuntos
Lectinas Tipo C/imunologia , Mariposas/parasitologia , Polydnaviridae , Vespas , Animais , Anticorpos Antivirais/metabolismo , Hemócitos/imunologia , Hemócitos/metabolismo , Interações Hospedeiro-Parasita/imunologia , Imunidade , Larva/imunologia , Larva/metabolismo , Larva/parasitologia , Lectinas Tipo C/metabolismo , Mariposas/imunologia , Polydnaviridae/metabolismo , Proteínas Virais/imunologia , Proteínas Virais/metabolismo , Vespas/patogenicidade , Vespas/virologia
20.
Mol Cell ; 81(12): 2656-2668.e8, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33930332

RESUMO

A deficient interferon (IFN) response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been implicated as a determinant of severe coronavirus disease 2019 (COVID-19). To identify the molecular effectors that govern IFN control of SARS-CoV-2 infection, we conducted a large-scale gain-of-function analysis that evaluated the impact of human IFN-stimulated genes (ISGs) on viral replication. A limited subset of ISGs were found to control viral infection, including endosomal factors inhibiting viral entry, RNA binding proteins suppressing viral RNA synthesis, and a highly enriched cluster of endoplasmic reticulum (ER)/Golgi-resident ISGs inhibiting viral assembly/egress. These included broad-acting antiviral ISGs and eight ISGs that specifically inhibited SARS-CoV-2 and SARS-CoV-1 replication. Among the broad-acting ISGs was BST2/tetherin, which impeded viral release and is antagonized by SARS-CoV-2 Orf7a protein. Overall, these data illuminate a set of ISGs that underlie innate immune control of SARS-CoV-2/SARS-CoV-1 infection, which will facilitate the understanding of host determinants that impact disease severity and offer potential therapeutic strategies for COVID-19.


Assuntos
Antígenos CD/genética , Interações Hospedeiro-Patógeno/genética , Fatores Reguladores de Interferon/genética , Interferon Tipo I/genética , SARS-CoV-2/genética , Proteínas Virais/genética , Animais , Antígenos CD/química , Antígenos CD/imunologia , Sítios de Ligação , Linhagem Celular Tumoral , Chlorocebus aethiops , Retículo Endoplasmático/genética , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/virologia , Proteínas Ligadas por GPI/química , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Regulação da Expressão Gênica , Complexo de Golgi/genética , Complexo de Golgi/imunologia , Complexo de Golgi/virologia , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Fatores Reguladores de Interferon/classificação , Fatores Reguladores de Interferon/imunologia , Interferon Tipo I/imunologia , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , SARS-CoV-2/imunologia , Transdução de Sinais , Células Vero , Proteínas Virais/química , Proteínas Virais/imunologia , Internalização do Vírus , Liberação de Vírus/genética , Liberação de Vírus/imunologia , Replicação Viral/genética , Replicação Viral/imunologia
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