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2.
Science ; 375(6579): 449-454, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34990214

RESUMO

Understanding broadly neutralizing sarbecovirus antibody responses is key to developing countermeasures against SARS-CoV-2 variants and future zoonotic sarbecoviruses. We describe the isolation and characterization of a human monoclonal antibody, designated S2K146, that broadly neutralizes viruses belonging to SARS-CoV- and SARS-CoV-2-related sarbecovirus clades which use ACE2 as an entry receptor. Structural and functional studies show that most of the virus residues that directly bind S2K146 are also involved in binding to ACE2. This allows the antibody to potently inhibit receptor attachment. S2K146 protects against SARS-CoV-2 Beta challenge in hamsters and viral passaging experiments reveal a high barrier for emergence of escape mutants, making it a good candidate for clinical development. The conserved ACE2-binding residues present a site of vulnerability that might be leveraged for developing vaccines eliciting broad sarbecovirus immunity.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/terapia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/química , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/química , Anticorpos Antivirais/metabolismo , Afinidade de Anticorpos , Anticorpos Amplamente Neutralizantes/química , Anticorpos Amplamente Neutralizantes/metabolismo , Anticorpos Amplamente Neutralizantes/uso terapêutico , COVID-19/imunologia , Reações Cruzadas , Microscopia Crioeletrônica , Epitopos , Humanos , Evasão da Resposta Imune , Mesocricetus , Modelos Moleculares , Mimetismo Molecular , Mutação , Conformação Proteica , Domínios Proteicos , Receptores de Coronavírus/química , Receptores de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
Science ; 375(6578): eabl6251, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34855508

RESUMO

Many studies have examined the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants on neutralizing antibody activity after they have become dominant strains. Here, we evaluate the consequences of further viral evolution. We demonstrate mechanisms through which the SARS-CoV-2 receptor binding domain (RBD) can tolerate large numbers of simultaneous antibody escape mutations and show that pseudotypes containing up to seven mutations, as opposed to the one to three found in previously studied variants of concern, are more resistant to neutralization by therapeutic antibodies and serum from vaccine recipients. We identify an antibody that binds the RBD core to neutralize pseudotypes for all tested variants but show that the RBD can acquire an N-linked glycan to escape neutralization. Our findings portend continued emergence of escape variants as SARS-CoV-2 adapts to humans.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Evasão da Resposta Imune , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Betacoronavirus/imunologia , COVID-19/imunologia , COVID-19/virologia , Reações Cruzadas , Microscopia Crioeletrônica , Cristalografia por Raios X , Epitopos , Evolução Molecular , Humanos , Modelos Moleculares , Mutação , Polissacarídeos/análise , Ligação Proteica , Domínios Proteicos , Receptores de Coronavírus/química , Receptores de Coronavírus/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
4.
J Med Virol ; 94(1): 186-196, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34427932

RESUMO

In classical viral infections, the avidity of immunoglobulin G (IgG) is low during acute infection and high a few months later. As recently reported, SARS-CoV-2 infections are not following this scheme, but they are rather characterized by incomplete avidity maturation. This study was performed to clarify whether infection with seasonal coronaviruses also leads to incomplete avidity maturation. The avidity of IgG toward the nucleoprotein (NP) of the seasonal coronaviruses 229E, NL63, OC43, HKU1 and of SARS-CoV-2 was determined in the sera from 88 healthy, SARS-CoV-2-negative subjects and in the sera from 70 COVID-19 outpatients, using the recomLine SARS-CoV-2 assay with recombinant antigens. In the sera from SARS-CoV-2-negative subjects, incomplete avidity maturation (persistent low and intermediate avidity indices) was the lowest for infections with the alpha-coronaviruses 229E (33.3%) and NL63 (61.3%), and the highest for the beta-coronaviruses OC43 (77.5%) and HKU1 (71.4%). In the sera from COVID-19 patients, the degree of incomplete avidity maturation of IgG toward NP of 223E, OC43, and HKU1 was not significantly different from that found in SARS-CoV-2-negative subjects, but a significant increase in avidity was observed for IgG toward NP of NL63. Though there was no cross-reaction between SARS-CoV-2 and seasonal coronaviruses, higher concentrations of IgG directed toward seasonal coronaviruses seemed to indirectly increase avidity maturation of IgG directed toward SARS-CoV-2. Our data show that incomplete IgG avidity maturation represents a characteristic consequence of coronavirus infections. This raises problems for the serological differentiation between acute and past infections and may be important for the biology of coronaviruses.


Assuntos
Alphacoronavirus/imunologia , Afinidade de Anticorpos , Betacoronavirus/imunologia , COVID-19/imunologia , Infecções por Coronavirus/imunologia , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Coronavirus Humano NL63/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Coronavirus Humano OC43/imunologia , Reações Cruzadas , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Estações do Ano , Adulto Jovem
5.
Viruses ; 13(11)2021 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-34835131

RESUMO

Many countries in sub-Saharan Africa have experienced lower COVID-19 caseloads and fewer deaths than countries in other regions worldwide. Under-reporting of cases and a younger population could partly account for these differences, but pre-existing immunity to coronaviruses is another potential factor. Blood samples from Sierra Leonean Lassa fever and Ebola survivors and their contacts collected before the first reported COVID-19 cases were assessed using enzyme-linked immunosorbent assays for the presence of antibodies binding to proteins of coronaviruses that infect humans. Results were compared to COVID-19 subjects and healthy blood donors from the United States. Prior to the pandemic, Sierra Leoneans had more frequent exposures than Americans to coronaviruses with epitopes that cross-react with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), SARS-CoV, and Middle Eastern respiratory syndrome coronavirus (MERS-CoV). The percentage of Sierra Leoneans with antibodies reacting to seasonal coronaviruses was also higher than for American blood donors. Serological responses to coronaviruses by Sierra Leoneans did not differ by age or sex. Approximately a quarter of Sierra Leonian pre-pandemic blood samples had neutralizing antibodies against SARS-CoV-2 pseudovirus, while about a third neutralized MERS-CoV pseudovirus. Prior exposures to coronaviruses that induce cross-protective immunity may contribute to reduced COVID-19 cases and deaths in Sierra Leone.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , SARS-CoV-2/imunologia , Distribuição por Idade , Alphacoronavirus/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Betacoronavirus/imunologia , Doadores de Sangue , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteção Cruzada , Reações Cruzadas , Epitopos , Feminino , Humanos , Masculino , Fosfoproteínas/imunologia , Serra Leoa , Estados Unidos
6.
Viruses ; 13(10)2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34696329

RESUMO

Antibodies targeting the spike (S) and nucleocapsid (N) proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are essential tools. In addition to important roles in the treatment and diagnosis of infection, the availability of high-quality specific antibodies for the S and N proteins is essential to facilitate basic research of virus replication and in the characterization of mutations responsible for variants of concern. We have developed panels of mouse and rabbit monoclonal antibodies (mAbs) to the SARS-CoV-2 spike receptor-binding domain (S-RBD) and N protein for functional and antigenic analyses. The mAbs to the S-RBD were tested for neutralization of native SARS-CoV-2, with several exhibiting neutralizing activity. The panels of mAbs to the N protein were assessed for cross-reactivity with the SARS-CoV and Middle East respiratory syndrome (MERS)-CoV N proteins and could be subdivided into sets that showed unique specificity for SARS-CoV-2 N protein, cross-reactivity between SARS-CoV-2 and SARS-CoV N proteins only, or cross-reactivity to all three coronavirus N proteins tested. Partial mapping of N-reactive mAbs were conducted using truncated fragments of the SARS-CoV-2 N protein and revealed near complete coverage of the N protein. Collectively, these sets of mouse and rabbit monoclonal antibodies can be used to examine structure/function studies for N proteins and to define the surface location of virus neutralizing epitopes on the RBD of the S protein.


Assuntos
Betacoronavirus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Sítios de Ligação/imunologia , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Reações Cruzadas , Epitopos/metabolismo , Humanos , Camundongos , Testes de Neutralização , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismo , Ligação Proteica/imunologia , Coelhos , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas do Envelope Viral/metabolismo
7.
Immunity ; 54(10): 2385-2398.e10, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34508662

RESUMO

Potent neutralizing SARS-CoV-2 antibodies often target the spike protein receptor-binding site (RBS), but the variability of RBS epitopes hampers broad neutralization of multiple sarbecoviruses and drifted viruses. Here, using humanized mice, we identified an RBS antibody with a germline VH gene that potently neutralized SARS-related coronaviruses, including SARS-CoV and SARS-CoV-2 variants. X-ray crystallography revealed coordinated recognition by the heavy chain of non-RBS conserved sites and the light chain of RBS with a binding angle mimicking the angiotensin-converting enzyme 2 (ACE2) receptor. The minimum footprints in the hypervariable region of RBS contributed to the breadth of neutralization, which was enhanced by immunoglobulin G3 (IgG3) class switching. The coordinated binding resulted in broad neutralization of SARS-CoV and emerging SARS-CoV-2 variants of concern. Low-dose therapeutic antibody treatment in hamsters reduced the virus titers and morbidity during SARS-CoV-2 challenge. The structural basis for broad neutralizing activity may inform the design of a broad spectrum of therapeutics and vaccines.


Assuntos
Anticorpos Amplamente Neutralizantes/imunologia , Reações Cruzadas/imunologia , SARS-CoV-2/imunologia , Animais , Betacoronavirus/imunologia , Sítios de Ligação de Anticorpos , Anticorpos Amplamente Neutralizantes/química , Anticorpos Amplamente Neutralizantes/uso terapêutico , COVID-19/prevenção & controle , COVID-19/terapia , COVID-19/virologia , Cricetinae , Humanos , Switching de Imunoglobulina , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/metabolismo , Imunoglobulina G/química , Imunoglobulina G/imunologia , Camundongos , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
9.
Front Immunol ; 12: 696370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34386006

RESUMO

The COVID-19 pandemic is caused by SARS-CoV-2, a novel zoonotic coronavirus. Emerging evidence indicates that preexisting humoral immunity against other seasonal human coronaviruses (HCoVs) plays a critical role in the specific antibody response to SARS-CoV-2. However, current work to assess the effects of preexisting and cross-reactive anti-HCoVs antibodies has been limited. To address this issue, we have adapted our previously reported multiplex assay to simultaneously and quantitatively measure anti-HCoV antibodies. The full mPlex-CoV panel covers the spike (S) and nucleocapsid (N) proteins of three highly pathogenic HCoVs (SARS-CoV-1, SARS-CoV-2, MERS) and four human seasonal strains (OC43, HKU1, NL63, 229E). Combining this assay with volumetric absorptive microsampling (VAMS), we measured the anti-HCoV IgG, IgA, and IgM antibodies in fingerstick blood samples. The results demonstrate that the mPlex-CoV assay has high specificity and sensitivity. It can detect strain-specific anti-HCoV antibodies down to 0.1 ng/ml with 4 log assay range and with low intra- and inter-assay coefficients of variation (%CV). We also estimate multiple strain HCoVs IgG, IgA and IgM concentration in VAMS samples in three categories of subjects: pre-COVID-19 (n=21), post-COVID-19 convalescents (n=19), and COVID-19 vaccine recipients (n=14). Using metric multidimensional scaling (MDS) analysis, HCoVs IgG concentrations in fingerstick blood samples were well separated between the pre-COVID-19, post-COVID-19 convalescents, and COVID-19 vaccine recipients. In addition, we demonstrate how multi-dimensional scaling analysis can be used to visualize IgG mediated antibody immunity against multiple human coronaviruses. We conclude that the combination of VAMS and the mPlex-Cov assay is well suited to performing remote study sample collection under pandemic conditions to monitor HCoVs antibody responses in population studies.


Assuntos
Anticorpos Antivirais/sangue , Coronavirus/imunologia , Reações Cruzadas/imunologia , Imunoensaio/métodos , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , COVID-19/imunologia , Coronavirus Humano 229E/imunologia , Coronavirus Humano NL63/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Coronavirus Humano OC43/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Vírus da SARS/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
10.
Science ; 373(6559): 1109-1116, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344823

RESUMO

The spillovers of betacoronaviruses in humans and the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants highlight the need for broad coronavirus countermeasures. We describe five monoclonal antibodies (mAbs) cross-reacting with the stem helix of multiple betacoronavirus spike glycoproteins isolated from COVID-19 convalescent individuals. Using structural and functional studies, we show that the mAb with the greatest breadth (S2P6) neutralizes pseudotyped viruses from three different subgenera through the inhibition of membrane fusion, and we delineate the molecular basis for its cross-reactivity. S2P6 reduces viral burden in hamsters challenged with SARS-CoV-2 through viral neutralization and Fc-mediated effector functions. Stem helix antibodies are rare, oftentimes of narrow specificity, and can acquire neutralization breadth through somatic mutations. These data provide a framework for structure-guided design of pan-betacoronavirus vaccines eliciting broad protection.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Betacoronavirus/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Internalização do Vírus , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Neutralizantes/isolamento & purificação , Convalescença , Cricetinae , Reações Cruzadas , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Células Jurkat , Pulmão/imunologia , Fusão de Membrana/imunologia , Testes de Neutralização , Mapeamento de Peptídeos , Conformação Proteica em alfa-Hélice , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Carga Viral/imunologia
11.
JCI Insight ; 6(16)2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34237028

RESUMO

Some studies suggest that recent common coronavirus (CCV) infections are associated with reduced COVID-19 severity upon SARS-CoV-2 infection. We completed serological assays using samples collected from health care workers to identify antibody types associated with SARS-CoV-2 protection and COVID-19 symptom duration. Rare SARS-CoV-2 cross-reactive antibodies elicited by past CCV infections were not associated with protection; however, the duration of symptoms following SARS-CoV-2 infections was significantly reduced in individuals with higher common betacoronavirus (ßCoV) antibody titers. Since antibody titers decline over time after CCV infections, individuals in our cohort with higher ßCoV antibody titers were more likely recently infected with common ßCoVs compared with individuals with lower antibody titers. Therefore, our data suggest that recent ßCoV infections potentially limit the duration of symptoms following SARS-CoV-2 infections through mechanisms that do not involve cross-reactive antibodies. Our data are consistent with the emerging hypothesis that cellular immune responses elicited by recent common ßCoV infections transiently reduce symptom duration following SARS-CoV-2 infections.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , COVID-19/imunologia , Pessoal de Saúde , SARS-CoV-2/imunologia , Adulto , Reações Cruzadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Arch Pathol Lab Med ; 145(10): 1194-1211, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34232978

RESUMO

CONTEXT.­: The purpose of this review was to compare 3 coronavirus diseases, including severe acute respiratory syndrome, Middle East respiratory syndrome, and COVID-19 caused by SARS-CoV, MERS-CoV, and SARS-CoV-2 viruses, respectively. OBJECTIVE.­: To cover the following topics: clinical considerations, viral characteristics, pathology, immune response, pathogenesis, and the prognosis associated with each coronavirus disease in humans. DATA SOURCES.­: Clinically, flu-like symptoms are usual at the time of presentation for all 3 diseases, but these vary from asymptomatic to severe multisystem involvement. The pathology associated with symptomatic severe acute respiratory syndrome and COVID-19 has been well described, the most prominent of which is diffuse alveolar damage. The immune response to each of these viruses is highly complex and includes both humoral and cellular components that can have a significant impact on prognosis. In severe cases of COVID-19, a dysregulated innate host immune system can initiate a hyperinflammatory syndrome dominated by endothelial dysfunction that can lead to a hypercoagulable state with microthrombi, resulting in a systemic microvascular and macrovascular disease. CONCLUSIONS.­: The severe acute respiratory syndrome and Middle East respiratory syndrome epidemics have been limited, involving approximately 8000 and 2500 individuals, respectively. In contrast, COVID-19 has resulted in a worldwide pandemic with more than 177 million cases and 3.9 million deaths as of June 15, 2021, and fatality rates ranging from less than 0.1% to approximately 10% depending upon the country. Ending on a positive note, the development of a number of vaccines, at least 6 of which now are in clinical use, should mitigate and eventually control the devastating COVID-19 pandemic.


Assuntos
COVID-19/imunologia , Infecções por Coronavirus/imunologia , Sistema Imunitário/imunologia , Síndrome Respiratória Aguda Grave/imunologia , Betacoronavirus/imunologia , Betacoronavirus/fisiologia , COVID-19/epidemiologia , COVID-19/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Pandemias/prevenção & controle , Prognóstico , Vírus da SARS/imunologia , Vírus da SARS/fisiologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/virologia
13.
Science ; 373(6558): 991-998, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34214046

RESUMO

The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003 and SARS-CoV-2 in 2019 highlights the need to develop universal vaccination strategies against the broader Sarbecovirus subgenus. Using chimeric spike designs, we demonstrate protection against challenge from SARS-CoV, SARS-CoV-2, SARS-CoV-2 B.1.351, bat CoV (Bt-CoV) RsSHC014, and a heterologous Bt-CoV WIV-1 in vulnerable aged mice. Chimeric spike messenger RNAs (mRNAs) induced high levels of broadly protective neutralizing antibodies against high-risk Sarbecoviruses. By contrast, SARS-CoV-2 mRNA vaccination not only showed a marked reduction in neutralizing titers against heterologous Sarbecoviruses, but SARS-CoV and WIV-1 challenge in mice resulted in breakthrough infections. Chimeric spike mRNA vaccines efficiently neutralized D614G, mink cluster five, and the UK B.1.1.7 and South African B.1.351 variants of concern. Thus, multiplexed-chimeric spikes can prevent SARS-like zoonotic coronavirus infections with pandemic potential.


Assuntos
Betacoronavirus/imunologia , Vacinas contra COVID-19/imunologia , Infecções por Coronavirus/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/fisiologia , COVID-19/prevenção & controle , Infecções por Coronavirus/imunologia , Proteção Cruzada , Citocinas/sangue , Feminino , Imunidade Heteróloga , Imunogenicidade da Vacina , Lipossomos , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas , Domínios Proteicos , Proteínas Recombinantes de Fusão , Vírus da SARS/imunologia , Vírus da SARS/fisiologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Replicação Viral
15.
Recurso na Internet em Inglês, Espanhol, Francês, Português | LIS - Localizador de Informação em Saúde | ID: lis-48230

RESUMO

Uma nova parceria entre o Governo do Canadá e a Organização Pan-Americana da Saúde (OPAS), destinada a melhorar a saúde e a proteção das populações em grande vulnerabilidade devido à COVID-19, particularmente as mulheres, foi anunciada hoje na 74ª Assembleia Mundial da Saúde.


Assuntos
Infecções por Coronavirus/prevenção & controle , Vacinação , América Latina , Região do Caribe , Populações Vulneráveis , Betacoronavirus/imunologia , Canadá , Organização Pan-Americana da Saúde/organização & administração
17.
Nat Commun ; 12(1): 2670, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976165

RESUMO

Understanding how antibody responses to SARS-CoV-2 evolve during infection may provide important insight into therapeutic approaches and vaccination for COVID-19. Here we profile the antibody responses of 162 COVID-19 symptomatic patients in the COVID-BioB cohort followed longitudinally for up to eight months from symptom onset to find SARS-CoV-2 neutralization, as well as antibodies either recognizing SARS-CoV-2 spike antigens and nucleoprotein, or specific for S2 antigen of seasonal beta-coronaviruses and hemagglutinin of the H1N1 flu virus. The presence of neutralizing antibodies within the first weeks from symptoms onset correlates with time to a negative swab result (p = 0.002), while the lack of neutralizing capacity correlates with an increased risk of a fatal outcome (p = 0.008). Neutralizing antibody titers progressively drop after 5-8 weeks but are still detectable up to 8 months in the majority of recovered patients regardless of age or co-morbidities, with IgG to spike antigens providing the best correlate of neutralization. Antibody responses to seasonal coronaviruses are temporarily boosted, and parallel those to SARS-CoV-2 without dampening the specific response or worsening disease progression. Our results thus suggest compromised immune responses to the SARS-CoV-2 spike to be a major trait of COVID-19 patients with critical conditions, and thereby inform on the planning of COVID-19 patient care and therapy prioritization.


Assuntos
Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , COVID-19/mortalidade , SARS-CoV-2/imunologia , Idoso , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Betacoronavirus/imunologia , COVID-19/virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Cinética , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/imunologia , Taxa de Sobrevida
18.
Nature ; 594(7864): 553-559, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33971664

RESUMO

Betacoronaviruses caused the outbreaks of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome, as well as the current pandemic of SARS coronavirus 2 (SARS-CoV-2)1-4. Vaccines that elicit protective immunity against SARS-CoV-2 and betacoronaviruses that circulate in animals have the potential to prevent future pandemics. Here we show that the immunization of macaques with nanoparticles conjugated with the receptor-binding domain of SARS-CoV-2, and adjuvanted with 3M-052 and alum, elicits cross-neutralizing antibody responses against bat coronaviruses, SARS-CoV and SARS-CoV-2 (including the B.1.1.7, P.1 and B.1.351 variants). Vaccination of macaques with these nanoparticles resulted in a 50% inhibitory reciprocal serum dilution (ID50) neutralization titre of 47,216 (geometric mean) for SARS-CoV-2, as well as in protection against SARS-CoV-2 in the upper and lower respiratory tracts. Nucleoside-modified mRNAs that encode a stabilized transmembrane spike or monomeric receptor-binding domain also induced cross-neutralizing antibody responses against SARS-CoV and bat coronaviruses, albeit at lower titres than achieved with the nanoparticles. These results demonstrate that current mRNA-based vaccines may provide some protection from future outbreaks of zoonotic betacoronaviruses, and provide a multimeric protein platform for the further development of vaccines against multiple (or all) betacoronaviruses.


Assuntos
Anticorpos Neutralizantes/imunologia , Betacoronavirus/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Resfriado Comum/prevenção & controle , Reações Cruzadas/imunologia , Pandemias , Vacinas Virais/imunologia , Adjuvantes Imunológicos , Administração Intranasal , Animais , COVID-19/epidemiologia , Vacinas contra COVID-19/imunologia , Resfriado Comum/imunologia , Resfriado Comum/virologia , Modelos Animais de Doenças , Feminino , Humanos , Macaca/imunologia , Masculino , Modelos Moleculares , Nanopartículas/química , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Traqueia , Vacinação
19.
Front Immunol ; 12: 675679, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995420

RESUMO

Background: COVID-19 Convalescent plasma (CCP) is safe and effective, particularly if given at an early stage of the disease. Our study aimed to identify an association between survival and specific antibodies found in CCP. Patients and Methods: Patients ≥18 years of age who were hospitalized with moderate to severe COVID-19 infection and received CCP at the MD Anderson Cancer Center between 4/30/2020 and 8/20/2020 were included in the study. We quantified the levels of anti-SARS-CoV-2 antibodies, as well as antibodies against antigens of other coronavirus strains, in the CCP units and compared antibody levels with patient outcomes. For each antibody, a Bayesian exponential survival time regression model including prognostic variables was fit, and the posterior probability of a beneficial effect (PBE) of higher antibody level on survival time was computed. Results: CCP was administered to 44 cancer patients. The median age was 60 years (range 37-84) and 19 (43%) were female. Twelve patients (27%) died of COVID-19-related complications. Higher levels of two non-SARS-CoV-2-specific antibodies, anti-HCoV-OC43 spike IgG and anti-HCoV-HKU1 spike IgG, had PBE = 1.00, and 4 SARS-CoV-2-specific antibodies had PBEs between 0.90 and 0.95. Other factors associated with better survival were shorter time to CCP administration, younger age, and female sex. Conclusions: Common cold coronavirus spike IgG antibodies anti-HCoV-OC43 and anti-HCoV-HKU1 may target a common domain for SARS-CoV-2 and other coronaviruses. They provide a promising therapeutic target for monoclonal antibody production.


Assuntos
Anticorpos Antivirais , Betacoronavirus/imunologia , COVID-19/terapia , Resfriado Comum/imunologia , Convalescença , Coronavirus Humano OC43/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/mortalidade , Reações Cruzadas , Feminino , Humanos , Imunização Passiva , Masculino , Pessoa de Meia-Idade
20.
Nat Struct Mol Biol ; 28(6): 478-486, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33981021

RESUMO

Three highly pathogenic ß-coronaviruses have crossed the animal-to-human species barrier in the past two decades: SARS-CoV, MERS-CoV and SARS-CoV-2. To evaluate the possibility of identifying antibodies with broad neutralizing activity, we isolated a monoclonal antibody, termed B6, that cross-reacts with eight ß-coronavirus spike glycoproteins, including all five human-infecting ß-coronaviruses. B6 broadly neutralizes entry of pseudotyped viruses from lineages A and C, but not from lineage B, and the latter includes SARS-CoV and SARS-CoV-2. Cryo-EM, X-ray crystallography and membrane fusion assays reveal that B6 binds to a conserved cryptic epitope located in the fusion machinery. The data indicate that antibody binding sterically interferes with the spike conformational changes leading to membrane fusion. Our data provide a structural framework explaining B6 cross-reactivity with ß-coronaviruses from three lineages, along with a proof of concept for antibody-mediated broad coronavirus neutralization elicited through vaccination. This study unveils an unexpected target for next-generation structure-guided design of a pan-ß-coronavirus vaccine.


Assuntos
Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Infecções por Coronavirus/prevenção & controle , Reações Cruzadas , Epitopos , Feminino , Células HEK293 , Humanos , Camundongos , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
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