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2.
Sci Immunol ; 5(48)2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527802

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that first emerged in late 2019 is responsible for a pandemic of severe respiratory illness. People infected with this highly contagious virus can present with clinically inapparent, mild, or severe disease. Currently, the virus infection in individuals and at the population level is being monitored by PCR testing of symptomatic patients for the presence of viral RNA. There is an urgent need for SARS-CoV-2 serologic tests to identify all infected individuals, irrespective of clinical symptoms, to conduct surveillance and implement strategies to contain spread. As the receptor binding domain (RBD) of the spike protein is poorly conserved between SARS-CoVs and other pathogenic human coronaviruses, the RBD represents a promising antigen for detecting CoV-specific antibodies in people. Here we use a large panel of human sera (63 SARS-CoV-2 patients and 71 control subjects) and hyperimmune sera from animals exposed to zoonotic CoVs to evaluate RBD's performance as an antigen for reliable detection of SARS-CoV-2-specific antibodies. By day 9 after the onset of symptoms, the recombinant SARS-CoV-2 RBD antigen was highly sensitive (98%) and specific (100%) for antibodies induced by SARS-CoVs. We observed a strong correlation between levels of RBD binding antibodies and SARS-CoV-2 neutralizing antibodies in patients. Our results, which reveal the early kinetics of SARS-CoV-2 antibody responses, support using the RBD antigen in serological diagnostic assays and RBD-specific antibody levels as a correlate of SARS-CoV-2 neutralizing antibodies in people.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Epitopos Imunodominantes/imunologia , Pneumonia Viral/diagnóstico , Domínios Proteicos/imunologia , Glicoproteína da Espícula de Coronavírus/química , Zoonoses/sangue , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Humanos , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/virologia , Ligação Proteica , Coelhos , Vírus da SARS/química , Vírus da SARS/imunologia , Testes Sorológicos , Zoonoses/virologia
3.
Nat Commun ; 11(1): 3202, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581217

RESUMO

The COVID-19 disease caused by the SARS-CoV-2 coronavirus has become a pandemic health crisis. An attractive target for antiviral inhibitors is the main protease 3CL Mpro due to its essential role in processing the polyproteins translated from viral RNA. Here we report the room temperature X-ray structure of unliganded SARS-CoV-2 3CL Mpro, revealing the ligand-free structure of the active site and the conformation of the catalytic site cavity at near-physiological temperature. Comparison with previously reported low-temperature ligand-free and inhibitor-bound structures suggest that the room temperature structure may provide more relevant information at physiological temperatures for aiding in molecular docking studies.


Assuntos
Betacoronavirus/enzimologia , Cisteína Endopeptidases/química , Proteínas não Estruturais Virais/química , Domínio Catalítico , Cristalografia por Raios X , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Estrutura Secundária de Proteína , Temperatura , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
4.
Proc Natl Acad Sci U S A ; 117(25): 13967-13974, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32503918

RESUMO

Molecular dynamics and free energy simulations have been carried out to elucidate the structural origin of differential protein-protein interactions between the common receptor protein angiotensin converting enzyme 2 (ACE2) and the receptor binding domains of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [A. E. Gorbalenya et al., Nat. Microbiol. 5, 536-544 (2020)] that causes coronavirus disease 2019 (COVID-19) [P. Zhou et al., Nature 579, 270-273 (2020)] and the SARS coronavirus in the 2002-2003 (SARS-CoV) [T. Kuiken et al., Lancet 362, 263-270 (2003)] outbreak. Analysis of the dynamic trajectories reveals that the binding interface consists of a primarily hydrophobic region and a delicate hydrogen-bonding network in the 2019 novel coronavirus. A key mutation from a hydrophobic residue in the SARS-CoV sequence to Lys417 in SARS-CoV-2 creates a salt bridge across the central hydrophobic contact region, which along with polar residue mutations results in greater electrostatic complementarity than that of the SARS-CoV complex. Furthermore, both electrostatic effects and enhanced hydrophobic packing due to removal of four out of five proline residues in a short 12-residue loop lead to conformation shift toward a more tilted binding groove in the complex in comparison with the SARS-CoV complex. On the other hand, hydrophobic contacts in the complex of the SARS-CoV-neutralizing antibody 80R are disrupted in the SARS-CoV-2 homology complex model, which is attributed to failure of recognition of SARS-CoV-2 by 80R.


Assuntos
Betacoronavirus/fisiologia , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/metabolismo , Aminoácidos/química , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , Infecções por Coronavirus , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Simulação de Dinâmica Molecular , Pandemias , Pneumonia Viral , Domínios Proteicos , Eletricidade Estática
5.
Int J Mol Sci ; 21(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486229

RESUMO

The novel coronavirus, COVID-19, caused by SARS-CoV-2, is a global health pandemic that started in December 2019. The effective drug target among coronaviruses is the main protease Mpro, because of its essential role in processing the polyproteins that are translated from the viral RNA. In this study, the bioactivity of some selected heterocyclic drugs named Favipiravir (1), Amodiaquine (2), 2'-Fluoro-2'-deoxycytidine (3), and Ribavirin (4) was evaluated as inhibitors and nucleotide analogues for COVID-19 using computational modeling strategies. The density functional theory (DFT) calculations were performed to estimate the thermal parameters, dipole moment, polarizability, and molecular electrostatic potential of the present drugs; additionally, Mulliken atomic charges of the drugs as well as the chemical reactivity descriptors were investigated. The nominated drugs were docked on SARS-CoV-2 main protease (PDB: 6LU7) to evaluate the binding affinity of these drugs. Besides, the computations data of DFT the docking simulation studies was predicted that the Amodiaquine (2) has the least binding energy (-7.77 Kcal/mol) and might serve as a good inhibitor to SARS-CoV-2 comparable with the approved medicines, hydroxychloroquine, and remdesivir which have binding affinity -6.06 and -4.96 Kcal/mol, respectively. The high binding affinity of 2 was attributed to the presence of three hydrogen bonds along with different hydrophobic interactions between the drug and the critical amino acids residues of the receptor. Finally, the estimated molecular electrostatic potential results by DFT were used to illustrate the molecular docking findings. The DFT calculations showed that drug 2 has the highest of lying HOMO, electrophilicity index, basicity, and dipole moment. All these parameters could share with different extent to significantly affect the binding affinity of these drugs with the active protein sites.


Assuntos
Antivirais/farmacologia , Cisteína Endopeptidases/química , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/química , Amidas/química , Amidas/farmacologia , Amodiaquina/química , Amodiaquina/farmacologia , Antivirais/química , Sítios de Ligação , Cisteína Endopeptidases/metabolismo , Inibidores de Proteases/química , Ligação Proteica , Pirazinas/química , Pirazinas/farmacologia , Ribavirina/química , Ribavirina/farmacologia , Proteínas não Estruturais Virais/metabolismo
6.
Molecules ; 25(11)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545268

RESUMO

Flavonoids are widely used as phytomedicines. Here, we report on flavonoid phytomedicines with potential for development into prophylactics or therapeutics against coronavirus disease 2019 (COVID-19). These flavonoid-based phytomedicines include: caflanone, Equivir, hesperetin, myricetin, and Linebacker. Our in silico studies show that these flavonoid-based molecules can bind with high affinity to the spike protein, helicase, and protease sites on the ACE2 receptor used by the severe acute respiratory syndrome coronavirus 2 to infect cells and cause COVID-19. Meanwhile, in vitro studies show potential of caflanone to inhibit virus entry factors including, ABL-2, cathepsin L, cytokines (IL-1ß, IL-6, IL-8, Mip-1α, TNF-α), and PI4Kiiiß as well as AXL-2, which facilitates mother-to-fetus transmission of coronavirus. The potential for the use of smart drug delivery technologies like nanoparticle drones loaded with these phytomedicines to overcome bioavailability limitations and improve therapeutic efficacy are discussed.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Coronavirus Humano OC43/efeitos dos fármacos , Flavonoides/farmacologia , Peptidil Dipeptidase A/química , Pneumonia Viral/tratamento farmacológico , Glicoproteína da Espícula de Coronavírus/química , Animais , Antivirais/química , Betacoronavirus/química , Betacoronavirus/crescimento & desenvolvimento , Sítios de Ligação , Cloroquina/química , Cloroquina/farmacologia , Infecções por Coronavirus/genética , Coronavirus Humano OC43/química , Coronavirus Humano OC43/crescimento & desenvolvimento , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Flavonoides/química , Humanos , Interleucinas/antagonistas & inibidores , Interleucinas/química , Interleucinas/genética , Interleucinas/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/virologia , Camundongos , Simulação de Acoplamento Molecular , Nanopartículas/administração & dosagem , Nanopartículas/química , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Fitoterapia/métodos , Pneumonia Viral/genética , Cultura Primária de Células , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Termodinâmica , Internalização do Vírus/efeitos dos fármacos
7.
Science ; 368(6495): 1081-1085, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32499435

RESUMO

The CTC1-STN1-TEN1 (CST) complex is essential for telomere maintenance and resolution of stalled replication forks genome-wide. Here, we report the 3.0-angstrom cryo-electron microscopy structure of human CST bound to telomeric single-stranded DNA (ssDNA), which assembles as a decameric supercomplex. The atomic model of the 134-kilodalton CTC1 subunit, built almost entirely de novo, reveals the overall architecture of CST and the DNA-binding anchor site. The carboxyl-terminal domain of STN1 interacts with CTC1 at two separate docking sites, allowing allosteric mediation of CST decamer assembly. Furthermore, ssDNA appears to staple two monomers to nucleate decamer assembly. CTC1 has stronger structural similarity to Replication Protein A than the expected similarity to yeast Cdc13. The decameric structure suggests that CST can organize ssDNA analogously to the nucleosome's organization of double-stranded DNA.


Assuntos
Complexos Multiproteicos/química , Homeostase do Telômero , Proteínas de Ligação a Telômeros/química , Telômero/química , Microscopia Crioeletrônica , DNA de Cadeia Simples/química , Células HEK293 , Humanos , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , Proteína de Replicação A/química
8.
Sheng Wu Gong Cheng Xue Bao ; 36(5): 969-978, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32567280

RESUMO

Drugs targeting immune checkpoint are used for cancer treatment, but resistance to single drug may occur. Combination therapy blocking multiple checkpoints simultaneously can improve clinical outcome. Therefore, we designed a recombinant protein rPC to block multiple targets, which consists of extracellular domains of programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4). The coding sequence was inserted into expression vector and stably transfected into HEK293 cells. The culture supernatant was collected and rPC was affinity-purified. Real-time quantitative PCR was used to evaluate the expression levels of ligands for PD-1 and CTLA-4 in several human cancer cell lines. The binding of rPC with cancer cells was examined by immunofluorescence cell staining, the influence of rPC on cancer cell growth was assayed by CCK-8. The results showed that rPC could be expressed and secreted by stably transfected HEK293 cells, the purified rPC could bind to lung cancer NCI-H226 cells which have high levels of ligands for PD-1 and CTLA-4, no direct impact on cancer cell growth could be observed by rPC treatment. The recombinant protein rPC can be functionally assayed further for developing novel immunotherapeutic drugs for cancer.


Assuntos
Neoplasias Pulmonares , Proteínas Recombinantes de Fusão , Animais , Antígeno CTLA-4/genética , Proliferação de Células , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Receptor de Morte Celular Programada 1/genética , Ligação Proteica , Domínios Proteicos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo
9.
Sci Rep ; 10(1): 9294, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518317

RESUMO

As of today, there is no antiviral for the treatment of the SARS-CoV-2 infection, and the development of a vaccine might take several months or even years. The structural superposition of the hepatitis C virus polymerase bound to sofosbuvir, a nucleoside analog antiviral approved for hepatitis C virus infections, with the SARS-CoV polymerase shows that the residues that bind to the drug are present in the latter. Moreover, a multiple alignment of several SARS-CoV-2, SARS and MERS-related coronaviruses polymerases shows that these residues are conserved in all these viruses, opening the possibility to use sofosbuvir against these highly infectious pathogens.


Assuntos
Antivirais/química , Betacoronavirus/enzimologia , Infecções por Coronavirus/virologia , Pandemias/prevenção & controle , Pneumonia Viral/virologia , RNA Replicase/química , Sofosbuvir/química , Proteínas não Estruturais Virais/química , Antivirais/uso terapêutico , Sequência de Bases , Domínio Catalítico , Simulação por Computador , Infecções por Coronavirus/tratamento farmacológico , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/enzimologia , Pneumonia Viral/tratamento farmacológico , Ligação Proteica , Estrutura Terciária de Proteína , RNA Replicase/genética , Vírus da SARS/enzimologia , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/virologia , Sofosbuvir/uso terapêutico , Proteínas não Estruturais Virais/genética
10.
Food Funct ; 11(6): 5565-5572, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32520031

RESUMO

To date, no specific drug has been discovered for the treatment of COVID-19 and hence, people are in a state of anxiety. Thus, there is an urgent need to search for various possible strategies including nutritional supplementation. In this study, we have tried to provide a reference for protein supplementation. Specifically, 20 marine fish proteins were subjected to in silico hydrolysis by gastrointestinal enzymes, and a large number of active peptides were generated. Then, the binding abilities of these peptides to SARS-CoV-2 main protease and monoamine oxidase A were assessed. The results showed that NADH dehydrogenase could be a good protein source in generating potent binders to the two enzymes, followed by cytochrome b. In addition, some high-affinity oligopeptides (VIQY, ICIY, PISQF, VISAW, AIPAW, and PVSQF) were identified as dual binders to the two enzymes. In summary, the supplementation of some fish proteins can be helpful for COVID-19 patients; the identified oligopeptides can be used as the lead compounds to design potential inhibitors against COVID-19 and anxiety.


Assuntos
Antivirais/metabolismo , Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Suplementos Nutricionais , Proteínas de Peixes/metabolismo , Monoaminoxidase/metabolismo , Pneumonia Viral/virologia , Animais , Antivirais/química , Antivirais/uso terapêutico , Organismos Aquáticos , Betacoronavirus/enzimologia , Infecções por Coronavirus/tratamento farmacológico , Decapodiformes/metabolismo , Proteínas de Peixes/química , Proteínas de Peixes/uso terapêutico , Peixes/metabolismo , Modelos Moleculares , Simulação de Acoplamento Molecular , Inibidores da Monoaminoxidase , Pandemias , Perciformes/metabolismo , Pneumonia Viral/tratamento farmacológico , Ligação Proteica , Conformação Proteica , Salmão/metabolismo , Atum/metabolismo
11.
Molecules ; 25(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32485894

RESUMO

The coronavirus disease, COVID-19, caused by the novel coronavirus SARS-CoV-2, which first emerged in Wuhan, China and was made known to the World in December 2019 turned into a pandemic causing more than 126,124 deaths worldwide up to April 16th, 2020. It has 79.5% sequence identity with SARS-CoV-1 and the same strategy for host cell invasion through the ACE-2 surface protein. Since the development of novel drugs is a long-lasting process, researchers look for effective substances among drugs already approved or developed for other purposes. The 3D structure of the SARS-CoV-2 main protease was compared with the 3D structures of seven proteases, which are drug targets, and docking analysis to the SARS-CoV-2 protease structure of thirty four approved and on-trial protease inhibitors was performed. Increased 3D structural similarity between the SARS-CoV-2 main protease, the HCV protease and α-thrombin was found. According to docking analysis the most promising results were found for HCV protease, DPP-4, α-thrombin and coagulation Factor Xa known inhibitors, with several of them exhibiting estimated free binding energy lower than -8.00 kcal/mol and better prediction results than reference compounds. Since some of the compounds are well-tolerated drugs, the promising in silico results may warrant further evaluation for viral anticipation. DPP-4 inhibitors with anti-viral action may be more useful for infected patients with diabetes, while anti-coagulant treatment is proposed in severe SARS-CoV-2 induced pneumonia.


Assuntos
Anticoagulantes/química , Antivirais/química , Betacoronavirus/efeitos dos fármacos , Inibidores da Dipeptidil Peptidase IV/química , Inibidores de Proteases/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Sequência de Aminoácidos , Anticoagulantes/farmacologia , Antivirais/farmacologia , Betacoronavirus/química , Betacoronavirus/enzimologia , Betacoronavirus/genética , Sítios de Ligação , Infecções por Coronavirus/tratamento farmacológico , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Fator Xa/química , Fator Xa/genética , Fator Xa/metabolismo , Hepacivirus/química , Hepacivirus/enzimologia , Hepacivirus/genética , Humanos , Simulação de Acoplamento Molecular , Pandemias , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Homologia Estrutural de Proteína , Especificidade por Substrato , Termodinâmica , Trombina/antagonistas & inibidores , Trombina/química , Trombina/genética , Trombina/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
12.
Hum Genomics ; 14(1): 20, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32498696

RESUMO

Coronavirus disease 2019 (COVID-19) is a declared pandemic that is spreading all over the world at a dreadfully fast rate. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the pathogen of COVID-19, infects the human body using angiotensin-converting enzyme 2 (ACE2) as a receptor identical to the severe acute respiratory syndrome (SARS) pandemic that occurred in 2002-2003. SARS-CoV-2 has a higher binding affinity to human ACE2 than to that of other species. Animal models that mimic the human disease are highly essential to develop therapeutics and vaccines against COVID-19. Here, we review transgenic mice that express human ACE2 in the airway and other epithelia and have shown to develop a rapidly lethal infection after intranasal inoculation with SARS-CoV, the pathogen of SARS. This literature review aims to present the importance of utilizing the human ACE2 transgenic mouse model to better understand the pathogenesis of COVID-19 and develop both therapeutics and vaccines.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/patologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Animais , Betacoronavirus/patogenicidade , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pandemias , Regiões Promotoras Genéticas/genética , Ligação Proteica/fisiologia , Receptores Virais/genética , Receptores Virais/metabolismo
13.
Science ; 368(6496): 1253-1257, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32527832

RESUMO

Transition paths of macromolecular conformational changes such as protein folding are predicted to be heterogeneous. However, experimental characterization of the diversity of transition paths is extremely challenging because it requires measuring more than one distance during individual transitions. In this work, we used fast three-color single-molecule Förster resonance energy transfer spectroscopy to obtain the distribution of binding transition paths of a disordered protein. About half of the transitions follow a path involving strong non-native electrostatic interactions, resulting in a transition time of 300 to 800 microseconds. The remaining half follow more diverse paths characterized by weaker electrostatic interactions and more than 10 times shorter transition path times. The chain flexibility and non-native interactions make diverse binding pathways possible, allowing disordered proteins to bind faster than folded proteins.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas Intrinsicamente Desordenadas/química , Dobramento de Proteína , Imagem Individual de Molécula/métodos , Ligação Proteica , Conformação Proteica , Eletricidade Estática
14.
Nat Commun ; 11(1): 2251, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366817

RESUMO

The emergence of the novel human coronavirus SARS-CoV-2 in Wuhan, China has caused a worldwide epidemic of respiratory disease (COVID-19). Vaccines and targeted therapeutics for treatment of this disease are currently lacking. Here we report a human monoclonal antibody that neutralizes SARS-CoV-2 (and SARS-CoV) in cell culture. This cross-neutralizing antibody targets a communal epitope on these viruses and may offer potential for prevention and treatment of COVID-19.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/farmacologia , Afinidade de Anticorpos/imunologia , Betacoronavirus/química , Betacoronavirus/efeitos dos fármacos , Chlorocebus aethiops , Sequência Conservada , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Reações Cruzadas/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Humanos , Técnicas In Vitro , Concentração Inibidora 50 , Modelos Moleculares , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos/imunologia , Receptores Virais/química , Receptores Virais/metabolismo , Vírus da SARS/química , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
15.
N Z Med J ; 133(1515): 112-118, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32438383

RESUMO

COVID-19 is a new zoonotic disease caused by the SARS-CoV-2 virus. Since its emergence in Wuhan City, China, the virus has rapidly spread across the globe causing calamitous health, economic and societal consequences. It causes disproportionately severe disease in the elderly and those with co-morbidities, such as hypertension and diabetes. There is currently no proven treatment for COVID-19 and a safe and effective vaccine is at least a year away. The virus gains access to the respiratory epithelium through cell surface angiotensin converting enzyme 2 (ACE2). The receptor binding domain (RBD) of the virus is unlikely to mutate without loss of pathogenicity and thus represents an attractive target for antiviral treatment. Inhaled modified recombinant human ACE2, may bind SARS-CoV-2 and mitigate lung damage. This decoy strategy is unlikely to provoke an adverse immune response and may reduce morbidity and mortality in high-risk groups.


Assuntos
Administração por Inalação , Infecções por Coronavirus/tratamento farmacológico , Peptidil Dipeptidase A/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Betacoronavirus , Humanos , Pulmão/virologia , Pandemias , Peptidil Dipeptidase A/administração & dosagem , Ligação Proteica , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Glicoproteína da Espícula de Coronavírus
16.
Life Sci ; 254: 117783, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413404

RESUMO

AIMS: This study aimed to examine the anti-fibrotic role of Nuclear Factor-Erythroid derived 2 (NF-E2) in human renal tubule (HK-11) cells and in type 1 and type 2 diabetic (T1D, T2D) mouse kidneys. MAIN METHODS: Anti-fibrotic effects of NF-E2 were examined in transforming growth factor-ß (TGF-ß) treated HK-11 cells by over-expressing/silencing NF-E2 expression and determining its effects on profibrotic signaling. NF-E2 proteasomal degradation was confirmed by proteasome inhibition in HK-11 cells and diabetic mice. Clinical relevance of changes in NF-E2 expression to fibrotic changes in the kidney were assessed in T1D and T2D mouse kidneys. KEY FINDINGS: NF-E2 expression was significantly decreased in TGF-ß treated HK-11 cells and in kidneys of diabetic mice with concurrent increase in expression of fibrotic proteins. TGF-ß treatment of HK-11 cells did not inhibit NF-E2 mRNA expression, suggesting that the post-translational changes may contribute to NF-E2 protein degradation. The down-regulation of NF-E2 expression was attributed to its proteasomal degradation, as TGF-ß- and diabetes-induced NF-E2 down regulation was prevented by proteasome inhibitor treatment. In HK-11 cells TGF-ß treatment decreased E-cadherin expression and induced pSer82Hsp27/NF-E2 association, likely to promote NF-E2 degradation, as Hsp27 can target proteins to the proteasome. A critical role for NF-E2 in regulation of renal fibrosis was demonstrated as over-expression of NF-E2 or silencing NF-E2 expression, decreased or increased profibrotic proteins in TGF-ß-treated HK-11 cells, respectively. SIGNIFICANCE: NF-E2, a novel anti-fibrotic protein, is down-regulated in diabetic kidneys. Preserving/inducing NF-E2 expression in diabetic kidneys may provide a therapeutic potential to combat DN.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Fibrose/fisiopatologia , Subunidade p45 do Fator de Transcrição NF-E2/fisiologia , Animais , Caderinas/biossíntese , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Diabetes Mellitus Experimental/genética , Regulação para Baixo , Fibrose/metabolismo , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP27/metabolismo , Humanos , Rim/metabolismo , Túbulos Renais/metabolismo , Leupeptinas/farmacologia , Masculino , Camundongos , Camundongos Transgênicos , Subunidade p45 do Fator de Transcrição NF-E2/biossíntese , Subunidade p45 do Fator de Transcrição NF-E2/genética , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/efeitos adversos , Fator de Crescimento Transformador beta/antagonistas & inibidores
17.
Nature ; 581(7808): 316-322, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433612

RESUMO

Toll-like receptors (TLRs) have a crucial role in the recognition of pathogens and initiation of immune responses1-3. Here we show that a previously uncharacterized protein encoded by CXorf21-a gene that is associated with systemic lupus erythematosus4,5-interacts with the endolysosomal transporter SLC15A4, an essential but poorly understood component of the endolysosomal TLR machinery also linked to autoimmune disease4,6-9. Loss of this type-I-interferon-inducible protein, which we refer to as 'TLR adaptor interacting with SLC15A4 on the lysosome' (TASL), abrogated responses to endolysosomal TLR agonists in both primary and transformed human immune cells. Deletion of SLC15A4 or TASL specifically impaired the activation of the IRF pathway without affecting NF-κB and MAPK signalling, which indicates that ligand recognition and TLR engagement in the endolysosome occurred normally. Extensive mutagenesis of TASL demonstrated that its localization and function relies on the interaction with SLC15A4. TASL contains a conserved pLxIS motif (in which p denotes a hydrophilic residue and x denotes any residue) that mediates the recruitment and activation of IRF5. This finding shows that TASL is an innate immune adaptor for TLR7, TLR8 and TLR9 signalling, revealing a clear mechanistic analogy with the IRF3 adaptors STING, MAVS and TRIF10,11. The identification of TASL as the component that links endolysosomal TLRs to the IRF5 transcription factor via SLC15A4 provides a mechanistic explanation for the involvement of these proteins in systemic lupus erythematosus12-14.


Assuntos
Fatores Reguladores de Interferon/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Motivos de Aminoácidos , Animais , Feminino , Humanos , Imunidade Inata , Interferon Tipo I/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Proteínas de Membrana Transportadoras/deficiência , Proteínas de Membrana Transportadoras/genética , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Ligação Proteica , Transdução de Sinais
18.
Emerg Microbes Infect ; 9(1): 1080-1091, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32471334

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) is a WHO priority pathogen for which vaccines are urgently needed. Using an immune-focusing approach, we created self-assembling particles multivalently displaying critical regions of the MERS-CoV spike protein ─fusion peptide, heptad repeat 2, and receptor binding domain (RBD) ─ and tested their immunogenicity and protective capacity in rabbits. Using a "plug-and-display" SpyTag/SpyCatcher system, we coupled RBD to lumazine synthase (LS) particles producing multimeric RBD-presenting particles (RBD-LS). RBD-LS vaccination induced antibody responses of high magnitude and quality (avidity, MERS-CoV neutralizing capacity, and mucosal immunity) with cross-clade neutralization. The antibody responses were associated with blocking viral replication and upper and lower respiratory tract protection against MERS-CoV infection in rabbits. This arrayed multivalent presentation of the viral RBD using the antigen-SpyTag/LS-SpyCatcher is a promising MERS-CoV vaccine candidate and this platform may be applied for the rapid development of vaccines against other emerging viruses such as SARS-CoV-2.


Assuntos
Formação de Anticorpos , Apresentação do Antígeno , Infecções por Coronavirus/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Sítios de Ligação , Infecções por Coronavirus/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Feminino , Vetores Genéticos , Células HEK293 , Humanos , Imunogenicidade da Vacina , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Testes de Neutralização , Ligação Proteica , Domínios Proteicos , Coelhos , Glicoproteína da Espícula de Coronavírus/biossíntese , Replicação Viral
19.
Mol Biol Rep ; 47(6): 4383-4392, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32410141

RESUMO

The ACE2 gene is a receptor of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) for COVID-19 (coronavirus disease 2019). To analyze the expression profiles and clinical significances for this gene in humans, RNA-seq data representing 27 different tissues were analyzed using NCBI; total RNA was extracted from different tissues of mouse and semi-quantitative reverse transcriptional-polymerase chain reaction (Q-RT-PCR) was carried out. Immunohistochemistry expression profiles in normal tissues and cancer tissues and TCGA survival analysis in renal and liver cancer were conducted. ACE2 was highly conserved in different species. In normal tissues, ACE2 expression distributions were organ-specific, mainly in the kidney, male testis and female breast, and cardiovascular and gastrointestinal systems. High level of expression in testis, cardiovascular and gastrointestinal system indicated that SARS-CoV-2 might not only attack the lungs, but also affect other organs, particularly the testes, thus it may severely damage male sexual development for younger male and lead to infertility in an adult male, if he contracted COVID-19. On the other side, high expression of ACE2 was correlated with increased survival rate in renal and liver cancer, indicating that ACE2 is a prognostic marker in both renal cancer and liver cancers. Thus, the ACE2 is a functional receptor for SARS-CoV-2 and has a potential anti-tumor role in cancer. Taken together, this study may not only provide potential clues for further medical pathogenesis of COVID-19 and male fertility, but also indicate the clinical significance of the role of the ACE2 gene in cancer.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Neoplasias Renais/genética , Neoplasias Hepáticas/genética , Peptidil Dipeptidase A/genética , Pneumonia Viral/epidemiologia , Receptores Virais/genética , Glicoproteína da Espícula de Coronavírus/genética , Adulto , Animais , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/genética , Bases de Dados Genéticas , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Humanos , Rim/metabolismo , Rim/patologia , Rim/virologia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Neoplasias Renais/virologia , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Masculino , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/virologia , Camundongos , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/diagnóstico , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/genética , Ligação Proteica , Receptores Virais/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus/metabolismo , Análise de Sobrevida , Testículo/metabolismo , Testículo/patologia , Testículo/virologia
20.
Life Sci ; 255: 117831, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32450166

RESUMO

A new SARS coronavirus (SARS-CoV-2) belonging to the genus Betacoronavirus has caused a pandemic known as COVID-19. Among coronaviruses, the main protease (Mpro) is an essential drug target which, along with papain-like proteases catalyzes the processing of polyproteins translated from viral RNA and recognizes specific cleavage sites. There are no human proteases with similar cleavage specificity and therefore, inhibitors are highly likely to be nontoxic. Therefore, targeting the SARS-CoV-2 Mpro enzyme with small molecules can block viral replication. The present study is aimed at the identification of promising lead molecules for SARS-CoV-2 Mpro enzyme through virtual screening of antiviral compounds from plants. The binding affinity of selected small drug-like molecules to SARS-CoV-2 Mpro, SARS-CoV Mpro and MERS-CoV Mpro were studied using molecular docking. Bonducellpin D was identified as the best lead molecule which shows higher binding affinity (-9.28 kcal/mol) as compared to the control (-8.24 kcal/mol). The molecular binding was stabilized through four hydrogen bonds with Glu166 and Thr190 as well as hydrophobic interactions via eight residues. The SARS-CoV-2 Mpro shows identities of 96.08% and 50.65% to that of SARS-CoV Mpro and MERS-CoV Mpro respectively at the sequence level. At the structural level, the root mean square deviation (RMSD) between SARS-CoV-2 Mpro and SARS-CoV Mpro was found to be 0.517 Å and 0.817 Å between SARS-CoV-2 Mpro and MERS-CoV Mpro. Bonducellpin D exhibited broad-spectrum inhibition potential against SARS-CoV Mpro and MERS-CoV Mpro and therefore is a promising drug candidate, which needs further validations through in vitro and in vivo studies.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/enzimologia , Infecções por Coronavirus/tratamento farmacológico , Extratos Vegetais/farmacologia , Pneumonia Viral/tratamento farmacológico , Proteínas não Estruturais Virais/antagonistas & inibidores , Sequência de Aminoácidos , Antivirais/química , Betacoronavirus/metabolismo , Sítios de Ligação , Simulação por Computador , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Simulação de Acoplamento Molecular , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Inibidores de Proteases/química , Ligação Proteica , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
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