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1.
Molecules ; 26(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770863

RESUMO

A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors.


Assuntos
Coronavirus/metabolismo , Interações entre Hospedeiro e Microrganismos/fisiologia , Receptores de Coronavírus/metabolismo , Anticorpos Neutralizantes , Antivirais/farmacologia , COVID-19 , Coronavirus/patogenicidade , Humanos , Receptores de Coronavírus/fisiologia , Receptores Virais/metabolismo , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos
2.
Lipids Health Dis ; 20(1): 126, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34602072

RESUMO

The coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). At present, the COVID-19 has been prevalent worldwide for more than a year and caused more than four million deaths. Liver injury was frequently observed in patients with COVID-19. Recently, a new definition of metabolic dysfunction associated fatty liver disease (MAFLD) was proposed by a panel of international experts, and the relationship between MAFLD and COVID-19 has been actively investigated. Several previous studies indicated that the patients with MAFLD had a higher prevalence of COVID-19 and a tendency to develop severe type of respiratory infection, and others indicated that liver injury would be exacerbated in the patients with MAFLD once infected with COVID-19. The mechanism underlying the relationship between MAFLD and COVID-19 infection has not been thoroughly investigated, and recent studies indicated that multifactorial mechanisms, such as altered host angiotensin converting enzyme 2 (ACE2) receptor expression, direct viral attack, disruption of cholangiocyte function, systemic inflammatory reaction, drug-induced liver injury, hepatic ischemic and hypoxic injury, and MAFLD-related glucose and lipid metabolic disorders, might jointly contribute to both of the adverse hepatic and respiratory outcomes. In this review, we discussed the relationship between MAFLD and COVID-19 based on current available literature, and summarized the recommendations for clinical management of MAFLD patients during the pandemic of COVID-19.


Assuntos
Anti-Inflamatórios/uso terapêutico , COVID-19/complicações , Doença Hepática Induzida por Substâncias e Drogas/complicações , Hipóxia/complicações , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , SARS-CoV-2/patogenicidade , Fatores Etários , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/tratamento farmacológico , COVID-19/patologia , COVID-19/virologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/virologia , Citocinas/genética , Citocinas/metabolismo , Dipeptídeos/uso terapêutico , Regulação da Expressão Gênica , Glucose/metabolismo , Ácido Glicirrízico/uso terapêutico , Humanos , Hipóxia/tratamento farmacológico , Hipóxia/patologia , Hipóxia/virologia , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/virologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/virologia , Receptores Virais/genética , Receptores Virais/metabolismo , Índice de Gravidade de Doença
3.
Gut Microbes ; 13(1): 1984105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34632957

RESUMO

Infection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is responsible for the COVID-19 pandemic. Angiotensin-converting enzyme 2 (Ace2) is expressed in the gastrointestinal (GI) tract and a receptor for SARS-CoV-2, making the GI tract a potential infection site. This study investigated the effects of commensal intestinal microbiota on colonic Ace2 expression using a humanized mouse model. We found that colonic Ace2 expression decreased significantly upon microbial colonization. Humanization with healthy volunteer or dysbiotic microbiota from irritable bowel syndrome (IBS) patients resulted in similar Ace2 expression. Despite the differences in microbiota, no associations between α-diversity, ß-diversity or individual taxa, and Ace2 were noted post-humanization. These results highlight that commensal microbiota play a key role in regulating intestinal Ace2 expression and the need to further examine the underlying mechanisms of this regulation.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Colo/metabolismo , Microbioma Gastrointestinal , Animais , Colo/microbiologia , Disbiose , Regulação da Expressão Gênica , Vida Livre de Germes , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Camundongos , Receptores Virais/metabolismo , SARS-CoV-2
4.
Viruses ; 13(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34696406

RESUMO

Coronaviruses (CoVs) are a group of enveloped positive-sense RNA viruses and can cause deadly diseases in animals and humans. Cell entry is the first and essential step of successful virus infection and can be divided into two ongoing steps: cell binding and membrane fusion. Over the past two decades, stimulated by the global outbreak of SARS-CoV and pandemic of SARS-CoV-2, numerous efforts have been made in the CoV research. As a result, significant progress has been achieved in our understanding of the cell entry process. Here, we review the current knowledge of this essential process, including the viral and host components involved in cell binding and membrane fusion, molecular mechanisms of their interactions, and the sites of virus entry. We highlight the recent findings of host restriction factors that inhibit CoVs entry. This knowledge not only enhances our understanding of the cell entry process, pathogenesis, tissue tropism, host range, and interspecies-transmission of CoVs but also provides a theoretical basis to design effective preventive and therapeutic strategies to control CoVs infection.


Assuntos
Infecções por Coronavirus/patologia , Coronavirus/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Ligação Viral , Internalização do Vírus , Animais , Gatos/virologia , Bovinos/virologia , Galinhas/virologia , Coronavirus/genética , Cães/virologia , Gado/virologia , Fusão de Membrana/fisiologia , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Suínos/virologia , Tropismo Viral/fisiologia
5.
PLoS Pathog ; 17(10): e1009996, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34648606

RESUMO

Members of the Old World Arenaviruses primarily utilize α-dystroglycan (α-DAG1) as a cellular receptor for infection. Mutations within the glycoprotein (GP) of lymphocytic choriomeningitis virus (LCMV) reduce or abrogate the binding affinity to α-DAG1 and thus influence viral persistence, kinetics, and cell tropism. The observation that α-DAG1 deficient cells are still highly susceptible to low affinity variants, suggests the use of an alternative receptor(s). In this study, we used a genome-wide CRISPR Cas9 knockout screen in DAG1 deficient 293T cells to identify host factors involved in α-DAG1-independent LCMV infection. By challenging cells with vesicular stomatitis virus (VSV), pseudotyped with the GP of LCMV WE HPI (VSV-GP), we identified the heparan sulfate (HS) biosynthesis pathway as an important host factor for low affinity LCMV infection. These results were confirmed by a genetic approach targeting EXTL3, a key factor in the HS biosynthesis pathway, as well as by enzymatic and chemical methods. Interestingly, a single point mutation within GP1 (S153F or Y155H) of WE HPI is sufficient for the switch from DAG1 to HS binding. Furthermore, we established a simple and reliable virus-binding assay, using directly labelled VSV-GP by intramolecular fusion of VSV-P and mWasabi, demonstrating the importance of HS for virus attachment but not entry in Burkitt lymphoma cells after reconstitution of HS expression. Collectively, our study highlights the essential role of HS for low affinity LCMV infection in contrast to their high affinity counterparts. Residual LCMV infection in double knockouts indicate the use of (a) still unknown entry receptor(s).


Assuntos
Proteoglicanas de Heparan Sulfato/metabolismo , Coriomeningite Linfocítica/metabolismo , Coriomeningite Linfocítica/transmissão , Vírus da Coriomeningite Linfocítica/metabolismo , Vírus da Coriomeningite Linfocítica/patogenicidade , Células HEK293 , Humanos , Receptores Virais/metabolismo
6.
Cell Rep ; 37(2): 109822, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34610292

RESUMO

Potent neutralizing monoclonal antibodies are one of the few agents currently available to treat COVID-19. SARS-CoV-2 variants of concern (VOCs) that carry multiple mutations in the viral spike protein can exhibit neutralization resistance, potentially affecting the effectiveness of some antibody-based therapeutics. Here, the generation of a diverse panel of 91 human, neutralizing monoclonal antibodies provides an in-depth structural and phenotypic definition of receptor binding domain (RBD) antigenic sites on the viral spike. These RBD antibodies ameliorate SARS-CoV-2 infection in mice and hamster models in a dose-dependent manner and in proportion to in vitro, neutralizing potency. Assessing the effect of mutations in the spike protein on antibody recognition and neutralization highlights both potent single antibodies and stereotypic classes of antibodies that are unaffected by currently circulating VOCs, such as B.1.351 and P.1. These neutralizing monoclonal antibodies and others that bind analogous epitopes represent potentially useful future anti-SARS-CoV-2 therapeutics.


Assuntos
Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Neutralizantes/imunologia , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/ultraestrutura , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Neutralizantes/ultraestrutura , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Cricetinae , Microscopia Crioeletrônica/métodos , Epitopos/imunologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Testes de Neutralização , Ligação Proteica/fisiologia , Receptores Virais/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
7.
Front Immunol ; 12: 741502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671355

RESUMO

Host innate immune response follows severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and it is the driver of the acute respiratory distress syndrome (ARDS) amongst other inflammatory end-organ morbidities. Such life-threatening coronavirus disease 2019 (COVID-19) is heralded by virus-induced activation of mononuclear phagocytes (MPs; monocytes, macrophages, and dendritic cells). MPs play substantial roles in aberrant immune secretory activities affecting profound systemic inflammation and end-organ malfunctions. All follow the presence of persistent viral components and virions without evidence of viral replication. To elucidate SARS-CoV-2-MP interactions we investigated transcriptomic and proteomic profiles of human monocyte-derived macrophages. While expression of the SARS-CoV-2 receptor, the angiotensin-converting enzyme 2, paralleled monocyte-macrophage differentiation, it failed to affect productive viral infection. In contrast, simple macrophage viral exposure led to robust pro-inflammatory cytokine and chemokine expression but attenuated type I interferon (IFN) activity. Both paralleled dysregulation of innate immune signaling pathways, specifically those linked to IFN. We conclude that the SARS-CoV-2-infected host mounts a robust innate immune response characterized by a pro-inflammatory storm heralding end-organ tissue damage.


Assuntos
COVID-19/virologia , Imunidade Inata , Macrófagos/virologia , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/imunologia , COVID-19/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata/genética , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Proteoma , Proteômica , Receptores Virais/genética , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Transdução de Sinais , Transcriptoma
8.
Nat Commun ; 12(1): 5449, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521834

RESUMO

During circulation in humans and natural selection to escape antibody recognition for decades, A/H3N2 influenza viruses emerged with altered receptor specificities. These viruses lost the ability to agglutinate erythrocytes critical for antigenic characterization and give low yields and acquire adaptive mutations when cultured in eggs and cells, contributing to recent vaccine challenges. Examination of receptor specificities of A/H3N2 viruses reveals that recent viruses compensated for decreased binding of the prototypic human receptor by recognizing α2,6-sialosides on extended LacNAc moieties. Erythrocyte glycomics shows an absence of extended glycans providing a rationale for lack of agglutination by recent A/H3N2 viruses. A glycan remodeling approach installing functional receptors on erythrocytes, allows antigenic characterization of recent A/H3N2 viruses confirming the cocirculation of antigenically different viruses in humans. Computational analysis of HAs in complex with sialosides having extended LacNAc moieties reveals that mutations distal to the RBD reoriented the Y159 side chain resulting in an extended receptor binding site.


Assuntos
Eritrócitos/virologia , Glicosídeos/química , Hemaglutininas Virais/química , Vírus da Influenza A Subtipo H3N2/genética , Polissacarídeos/química , Receptores Virais/química , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/metabolismo , Sítios de Ligação , Sequência de Carboidratos , Eritrócitos/metabolismo , Glicômica/métodos , Glicosídeos/metabolismo , Testes de Inibição da Hemaglutinação , Hemaglutininas Virais/genética , Hemaglutininas Virais/metabolismo , Interações Hospedeiro-Patógeno/genética , Humanos , Vírus da Influenza A Subtipo H3N2/metabolismo , Influenza Humana/virologia , Análise em Microsséries/métodos , Polissacarídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Receptores Virais/genética , Receptores Virais/metabolismo , Ácidos Siálicos/química , Ácidos Siálicos/metabolismo
9.
Molecules ; 26(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34577194

RESUMO

The novel coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initially appeared in Wuhan, China, in December 2019. Elderly individuals and those with comorbid conditions may be more vulnerable to this disease. Consequently, several research laboratories continue to focus on developing drugs to treat this infection because this disease has developed into a global pandemic with an extremely limited number of specific treatments available. Natural herbal remedies have long been used to treat illnesses in a variety of cultures. Modern medicine has achieved success due to the effectiveness of traditional medicines, which are derived from medicinal plants. The objective of this study was to determine whether components of natural origin from Iranian medicinal plants have an antiviral effect that can prevent humans from this coronavirus infection using the most reliable molecular docking method; in our case, we focused on the main protease (Mpro) and a receptor-binding domain (RBD). The results of molecular docking showed that among 169 molecules of natural origin from common Iranian medicinal plants, 20 molecules (chelidimerine, rutin, fumariline, catechin gallate, adlumidine, astragalin, somniferine, etc.) can be proposed as inhibitors against this coronavirus based on the binding free energy and type of interactions between these molecules and the studied proteins. Moreover, a molecular dynamics simulation study revealed that the chelidimerine-Mpro and somniferine-RBD complexes were stable for up to 50 ns below 0.5 nm. Our results provide valuable insights into this mechanism, which sheds light on future structure-based designs of high-potency inhibitors for SARS-CoV-2.


Assuntos
COVID-19/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Inibidores de Protease Viral/química , Antivirais/farmacologia , Simulação por Computador , Humanos , Irã (Geográfico) , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Compostos Fitoquímicos/metabolismo , Plantas Medicinais/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Ligação Proteica , Receptores Virais/química , Receptores Virais/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Termodinâmica , Inibidores de Protease Viral/metabolismo , Inibidores de Protease Viral/farmacologia
10.
Nat Microbiol ; 6(10): 1219-1232, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34471255

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has claimed millions of lives and caused a global economic crisis. No effective antiviral drugs are currently available to treat infections of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The medical need imposed by the pandemic has spurred unprecedented research efforts to study coronavirus biology. Every virus depends on cellular host factors and pathways for successful replication. These proviral host factors represent attractive targets for antiviral therapy as they are genetically more stable than viral targets and may be shared among related viruses. The application of various 'omics' technologies has led to the rapid discovery of proviral host factors that are required for the completion of the SARS-CoV-2 life cycle. In this Review, we summarize insights into the proviral host factors that are required for SARS-CoV-2 infection that were mainly obtained using functional genetic and interactome screens. We discuss cellular processes that are important for the SARS-CoV-2 life cycle, as well as parallels with non-coronaviruses. Finally, we highlight host factors that could be targeted by clinically approved molecules and molecules in clinical trials as potential antiviral therapies for COVID-19.


Assuntos
COVID-19/metabolismo , SARS-CoV-2/fisiologia , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Peptídeo Hidrolases/metabolismo , RNA Viral/metabolismo , Receptores Virais/metabolismo , SARS-CoV-2/efeitos dos fármacos , Proteínas Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
11.
Cells ; 10(9)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34572076

RESUMO

Coronavirus disease 19 (COVID-19) is caused by an enveloped, positive-sense, single-stranded RNA virus, referred to as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which belongs to the realm Riboviria, order Nidovirales, family Coronaviridae, genus Betacoronavirus and the species Severe acute respiratory syndrome-related coronavirus. This viral disease is characterized by a myriad of varying symptoms, such as pyrexia, cough, hemoptysis, dyspnoea, diarrhea, muscle soreness, dysosmia, lymphopenia and dysgeusia amongst others. The virus mainly infects humans, various other mammals, avian species and some other companion livestock. SARS-CoV-2 cellular entry is primarily accomplished by molecular interaction between the virus's spike (S) protein and the host cell surface receptor, angiotensin-converting enzyme 2 (ACE2), although other host cell-associated receptors/factors, such as neuropilin 1 (NRP-1) and neuropilin 2 (NRP-2), C-type lectin receptors (CLRs), as well as proteases such as TMPRSS2 (transmembrane serine protease 2) and furin, might also play a crucial role in infection, tropism, pathogenesis and clinical outcome. Furthermore, several structural and non-structural proteins of the virus themselves are very critical in determining the clinical outcome following infection. Considering such critical role(s) of the abovementioned host cell receptors, associated proteases/factors and virus structural/non-structural proteins (NSPs), it may be quite prudent to therapeutically target them through a multipronged clinical regimen to combat the disease.


Assuntos
COVID-19 , Interações entre Hospedeiro e Microrganismos , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/patologia , COVID-19/virologia , Sistemas de Liberação de Medicamentos , Furina/química , Furina/metabolismo , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Estrutura Molecular , Neuropilinas/química , Neuropilinas/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Resultado do Tratamento , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Internalização do Vírus
12.
Physiol Rep ; 9(17): e15014, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34523264

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is threatening people's lives and impacting their health. It is still unclear whether people engaged in physical activity are at an increased risk of SARS-CoV-2 infection and severe forms of COVID-19. In order to provide data to help answer this question, we, therefore, investigated the effects of endurance training on the levels of host proteins involved in SARS-CoV-2 infection in mice. Eight-week-old C57BL/6J mice were subjected to treadmill running (17-25 m/min, 60-90 min, 5 sessions/week, 8 weeks). After the intervention, the levels of angiotensin-converting enzyme 2 (ACE2; host receptor for SARS-CoV-2), transmembrane protease serine 2 (TMPRSS2; host protease priming fusion of SARS-CoV-2 to host cell membranes), FURIN (host protease that promotes binding of SARS-CoV-2 to host receptors), and Neuropilin-1 (host coreceptor for SARS-CoV-2) were measured in 10 organs that SARS-CoV-2 can infect (larynx, trachea, lung, heart, jejunum, ileum, colon, liver, kidney, and testis). Six organs (heart, lung, jejunum, liver, trachea, and ileum) showed changes in the levels of at least one of the proteins. Endurance training increased ACE2 levels in heart (+66.4%), lung (+37.1%), jejunum (+24.7%) and liver (+27.4%), and FURIN in liver (+17.9%) tissue. In contrast, endurance training decreased Neuropilin-1 levels in liver (-39.7%), trachea (-41.2%), and ileum (-39.7%), and TMPRSS2 in lung (-11.3%). Taken together, endurance training altered the levels of host proteins involved in SARS-CoV-2 cell entry in an organ-dependent manner.


Assuntos
COVID-19/virologia , Condicionamento Físico Animal , Resistência Física , Receptores Virais/metabolismo , SARS-CoV-2/patogenicidade , Internalização do Vírus , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/enzimologia , Furina/metabolismo , Interações Hospedeiro-Patógeno , Masculino , Camundongos Endogâmicos C57BL , Neuropilina-1/metabolismo , Corrida , Serina Endopeptidases/metabolismo
13.
Nat Commun ; 12(1): 5407, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518528

RESUMO

Most of the ongoing projects aimed at the development of specific therapies and vaccines against COVID-19 use the SARS-CoV-2 spike (S) protein as the main target. The binding of the spike protein with the ACE2 receptor (ACE2) of the host cell constitutes the first and key step for virus entry. During this process, the receptor binding domain (RBD) of the S protein plays an essential role, since it contains the receptor binding motif (RBM), responsible for the docking to the receptor. So far, mostly biochemical methods are being tested in order to prevent binding of the virus to ACE2. Here we show, with the help of atomistic simulations, that external electric fields of easily achievable and moderate strengths can dramatically destabilise the S protein, inducing long-lasting structural damage. One striking field-induced conformational change occurs at the level of the recognition loop L3 of the RBD where two parallel beta sheets, believed to be responsible for a high affinity to ACE2, undergo a change into an unstructured coil, which exhibits almost no binding possibilities to the ACE2 receptor. We also show that these severe structural changes upon electric-field application also occur in the mutant RBDs corresponding to the variants of concern (VOC) B.1.1.7 (UK), B.1.351 (South Africa) and P.1 (Brazil). Remarkably, while the structural flexibility of S allows the virus to improve its probability of entering the cell, it is also the origin of the surprising vulnerability of S upon application of electric fields of strengths at least two orders of magnitude smaller than those required for damaging most proteins. Our findings suggest the existence of a clean physical method to weaken the SARS-CoV-2 virus without further biochemical processing. Moreover, the effect could be used for infection prevention purposes and also to develop technologies for in-vitro structural manipulation of S. Since the method is largely unspecific, it can be suitable for application to other mutations in S, to other proteins of SARS-CoV-2 and in general to membrane proteins of other virus types.


Assuntos
SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Enzima de Conversão de Angiotensina 2 , Sítios de Ligação , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Ligação Proteica/efeitos dos fármacos , Conformação Proteica , Conformação Proteica em Folha beta , Receptores Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos
14.
Virus Res ; 305: 198563, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34530046

RESUMO

This study compared the lethality of severe acute respiratory syndrome coronavirus 2 variants belonging to the S, V, L, G, GH, and GR clades using K18-human angiotensin-converting enzyme 2 heterozygous mice. To estimate the 50% lethal dose (LD50) of each variant, increasing viral loads (100-104 plaque-forming units [PFU]) were administered intranasally. Mouse weight and survival were monitored for 14 days. The LD50 of the GH and GR clades was significantly lower than that of other clades at 50 PFU. These findings suggest that the GH and GR clades, which are prevalent worldwide, are more virulent than the other clades.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , COVID-19/mortalidade , Receptores Virais/genética , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Carga Viral/genética , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Sequência de Bases , Peso Corporal , COVID-19/patologia , COVID-19/virologia , Chlorocebus aethiops , Expressão Gênica , Humanos , Dose Letal Mediana , Masculino , Camundongos , Camundongos Transgênicos , Filogenia , Receptores Virais/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/metabolismo , Índice de Gravidade de Doença , Análise de Sobrevida , Transgenes , Células Vero , Ensaio de Placa Viral , Virulência
15.
Cell Rep ; 36(13): 109760, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34534459

RESUMO

Many anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) neutralizing antibodies target the angiotensin-converting enzyme 2 (ACE2) binding site on viral spike receptor-binding domains (RBDs). Potent antibodies recognize exposed variable epitopes, often rendering them ineffective against other sarbecoviruses and SARS-CoV-2 variants. Class 4 anti-RBD antibodies against a less-exposed, but more-conserved, cryptic epitope could recognize newly emergent zoonotic sarbecoviruses and variants, but they usually show only weak neutralization potencies. Here, we characterize two class 4 anti-RBD antibodies derived from coronavirus disease 2019 (COVID-19) donors that exhibit breadth and potent neutralization of zoonotic coronaviruses and SARS-CoV-2 variants. C118-RBD and C022-RBD structures reveal orientations that extend from the cryptic epitope to occlude ACE2 binding and CDRH3-RBD main-chain H-bond interactions that extend an RBD ß sheet, thus reducing sensitivity to RBD side-chain changes. A C118-spike trimer structure reveals rotated RBDs that allow access to the cryptic epitope and the potential for intra-spike crosslinking to increase avidity. These studies facilitate vaccine design and illustrate potential advantages of class 4 RBD-binding antibody therapeutics.


Assuntos
Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Sítios de Ligação/imunologia , Anticorpos Amplamente Neutralizantes/farmacologia , Reações Cruzadas , Epitopos/metabolismo , Humanos , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptores Virais/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia
16.
Nat Commun ; 12(1): 5652, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34580306

RESUMO

The emergence of numerous variants of SARS-CoV-2, the causative agent of COVID-19, has presented new challenges to the global efforts to control the COVID-19 pandemic. Here, we obtain two cross-neutralizing antibodies (7D6 and 6D6) that target Sarbecoviruses' receptor-binding domain (RBD) with sub-picomolar affinities and potently neutralize authentic SARS-CoV-2. Crystal structures show that both antibodies bind a cryptic site different from that recognized by existing antibodies and highly conserved across Sarbecovirus isolates. Binding of these two antibodies to the RBD clashes with the adjacent N-terminal domain and disrupts the viral spike. Both antibodies confer good resistance to mutations in the currently circulating SARS-CoV-2 variants. Thus, our results have direct relevance to public health as options for passive antibody therapeutics and even active prophylactics. They can also inform the design of pan-sarbecovirus vaccines.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/terapia , Imunização Passiva/métodos , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/isolamento & purificação , Anticorpos Antivirais/metabolismo , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Anticorpos Amplamente Neutralizantes/administração & dosagem , Anticorpos Amplamente Neutralizantes/isolamento & purificação , Anticorpos Amplamente Neutralizantes/metabolismo , Células CHO , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/virologia , Chlorocebus aethiops , Cricetulus , Epitopos/imunologia , Células HEK293 , Humanos , Camundongos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Testes de Neutralização , Pandemias/prevenção & controle , Multimerização Proteica , Receptores Virais/metabolismo , SARS-CoV-2/genética , Células Sf9 , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero
17.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34470866

RESUMO

Emergence of novel variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscores the need for next-generation vaccines able to elicit broad and durable immunity. Here we report the evaluation of a ferritin nanoparticle vaccine displaying the receptor-binding domain of the SARS-CoV-2 spike protein (RFN) adjuvanted with Army Liposomal Formulation QS-21 (ALFQ). RFN vaccination of macaques using a two-dose regimen resulted in robust, predominantly Th1 CD4+ T cell responses and reciprocal peak mean serum neutralizing antibody titers of 14,000 to 21,000. Rapid control of viral replication was achieved in the upper and lower airways of animals after high-dose SARS-CoV-2 respiratory challenge, with undetectable replication within 4 d in seven of eight animals receiving 50 µg of RFN. Cross-neutralization activity against SARS-CoV-2 variant B.1.351 decreased only approximately twofold relative to WA1/2020. In addition, neutralizing, effector antibody and cellular responses targeted the heterotypic SARS-CoV-1, highlighting the broad immunogenicity of RFN-ALFQ for SARS-CoV-like Sarbecovirus vaccine development.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/virologia , Macaca mulatta/imunologia , Nanopartículas/química , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Ferritinas/química , SARS-CoV-2/metabolismo , Linfócitos T/imunologia
19.
Bioengineered ; 12(1): 4054-4069, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34369278

RESUMO

During the pandemic of the coronavirus disease 2019, there exist quite a few studies on angiotensin-converting enzyme 2 (ACE2) and SARS-CoV-2 infection, while little is known about ACE2 in hepatocellular carcinoma (HCC). The detailed mechanism among ACE2 and HCC still remains unclear, which needs to be further investigated. In the current study with a total of 6,926 samples, ACE2 expression was downregulated in HCC compared with non-HCC samples (standardized mean difference = -0.41). With the area under the curve of summary receiver operating characteristic = 0.82, ACE2 expression showed a better ability to differentiate HCC from non-HCC. The mRNA expression of ACE2 was related to the age, alpha-fetoprotein levels and cirrhosis of HCC patients, and it was identified as a protected factor for HCC patients via Kaplan-Meier survival, Cox regression analyses. The potential molecular mechanism of ACE2 may be relevant to catabolic and cell division. In all, decreasing ACE2 expression can be seen in HCC, and its protective role for HCC patients and underlying mechanisms were explored in the study.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , Carcinoma Hepatocelular/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Proteínas de Neoplasias/genética , Receptores Virais/genética , alfa-Fetoproteínas/genética , Fatores Etários , Idoso , Enzima de Conversão de Angiotensina 2/metabolismo , Área Sob a Curva , COVID-19/virologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/classificação , Proteínas de Neoplasias/metabolismo , Fatores de Proteção , Mapeamento de Interação de Proteínas , Curva ROC , Receptores Virais/metabolismo , SARS-CoV-2/patogenicidade , Análise de Sobrevida , alfa-Fetoproteínas/metabolismo
20.
Elife ; 102021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34338634

RESUMO

Combating the COVID-19 pandemic requires potent and low-cost therapeutics. We identified a series of single-domain antibodies (i.e., nanobody), Nanosota-1, from a camelid nanobody phage display library. Structural data showed that Nanosota-1 bound to the oft-hidden receptor-binding domain (RBD) of SARS-CoV-2 spike protein, blocking viral receptor angiotensin-converting enzyme 2 (ACE2). The lead drug candidate possessing an Fc tag (Nanosota-1C-Fc) bound to SARS-CoV-2 RBD ~3000 times more tightly than ACE2 did and inhibited SARS-CoV-2 pseudovirus ~160 times more efficiently than ACE2 did. Administered at a single dose, Nanosota-1C-Fc demonstrated preventive and therapeutic efficacy against live SARS-CoV-2 infection in both hamster and mouse models. Unlike conventional antibodies, Nanosota-1C-Fc was produced at high yields in bacteria and had exceptional thermostability. Pharmacokinetic analysis of Nanosota-1C-Fc documented an excellent in vivo stability and a high tissue bioavailability. As effective and inexpensive drug candidates, Nanosota-1 may contribute to the battle against COVID-19.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/tratamento farmacológico , SARS-CoV-2/efeitos dos fármacos , Anticorpos de Domínio Único/farmacologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , COVID-19/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Moleculares , Pandemias , Ligação Proteica , Conformação Proteica , Receptores Virais/imunologia , Receptores Virais/metabolismo , Anticorpos de Domínio Único/química , Glicoproteína da Espícula de Coronavírus/metabolismo
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