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1.
PLoS Pathog ; 16(8): e1008775, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866218

RESUMO

Small RNA viruses only have a very limited coding capacity, thus most viral proteins have evolved to fulfill multiple functions. The highly conserved matrix protein 1 (M1) of influenza A viruses is a prime example for such a multifunctional protein, as it acts as a master regulator of virus replication whose different functions have to be tightly regulated. The underlying mechanisms, however, are still incompletely understood. Increasing evidence points towards an involvement of posttranslational modifications in the spatio-temporal regulation of M1 functions. Here, we analyzed the role of M1 tyrosine phosphorylation in genuine infection by using recombinant viruses expressing M1 phosphomutants. Presence of M1 Y132A led to significantly decreased viral replication compared to wildtype and M1 Y10F. Characterization of phosphorylation dynamics by mass spectrometry revealed the presence of Y132 phosphorylation in M1 incorporated into virions that is most likely mediated by membrane-associated Janus kinases late upon infection. Molecular dynamics simulations unraveled a potential phosphorylation-induced exposure of the positively charged linker domain between helices 4 and 5, supposably acting as interaction platform during viral assembly. Consistently, M1 Y132A showed a defect in lipid raft localization due to reduced interaction with viral HA protein resulting in a diminished structural stability of viral progeny and the formation of filamentous particles. Importantly, reduced M1-RNA binding affinity resulted in an inefficient viral genome incorporation and the production of non-infectious virions that interferes with virus pathogenicity in mice. This study advances our understanding of the importance of dynamic phosphorylation as a so far underestimated level of regulation of multifunctional viral proteins and emphasizes the potential feasibility of targeting posttranslational modifications of M1 as a novel antiviral intervention.


Assuntos
Vírus da Influenza A/metabolismo , Mutação de Sentido Incorreto , Proteínas da Matriz Viral/metabolismo , Células A549 , Substituição de Aminoácidos , Animais , Cães , Feminino , Células HEK293 , Humanos , Vírus da Influenza A/genética , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Transgênicos , Fosforilação , Proteínas da Matriz Viral/genética
2.
PLoS Pathog ; 16(9): e1008841, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881973

RESUMO

The influenza virus polymerase transcribes and replicates the viral genome. The proper timing and balance of polymerase activity is important for successful replication. Genome replication is controlled in part by phosphorylation of NP that regulates assembly of the replication machinery. However, it remains unclear whether phosphorylation directly regulated polymerase activity. Here we identified polymerase phosphosites that control its function. Mutating phosphosites in the catalytic subunit PB1 altered polymerase activity and virus replication. Biochemical analyses revealed phosphorylation events that disrupted global polymerase function by blocking the NTP entry channel or preventing RNA binding. We also identified a regulatory site that split polymerase function by specifically suppressing transcription. These experiments show that host kinases phospho-regulate viral RNA synthesis directly by modulating polymerase activity and indirectly by controlling assembly of replication machinery. Further, they suggest polymerase phosphorylation may bias replication versus transcription at discrete times or locations during the infectious cycle.


Assuntos
Vírus da Influenza A/fisiologia , RNA Viral/biossíntese , Transcrição Genética , Proteínas Virais/metabolismo , Replicação Viral , Células A549 , Animais , Cães , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Fosforilação , RNA Viral/genética , Proteínas Virais/genética
3.
Sci Adv ; 6(35): eaba7910, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923629

RESUMO

Targeting a universal host protein exploited by most viruses would be a game-changing strategy that offers broad-spectrum solution and rapid pandemic control including the current COVID-19. Here, we found a common YxxØ-motif of multiple viruses that exploits host AP2M1 for intracellular trafficking. A library chemical, N-(p-amylcinnamoyl)anthranilic acid (ACA), was identified to interrupt AP2M1-virus interaction and exhibit potent antiviral efficacy against a number of viruses in vitro and in vivo, including the influenza A viruses (IAVs), Zika virus (ZIKV), human immunodeficiency virus, and coronaviruses including MERS-CoV and SARS-CoV-2. YxxØ mutation, AP2M1 depletion, or disruption by ACA causes incorrect localization of viral proteins, which is exemplified by the failure of nuclear import of IAV nucleoprotein and diminished endoplasmic reticulum localization of ZIKV-NS3 and enterovirus-A71-2C proteins, thereby suppressing viral replication. Our study reveals an evolutionarily conserved mechanism of protein-protein interaction between host and virus that can serve as a broad-spectrum antiviral target.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Antivirais/farmacologia , Cinamatos/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Influenza Humana/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , ortoaminobenzoatos/farmacologia , Células A549 , Animais , Betacoronavirus/efeitos dos fármacos , Sítios de Ligação/genética , Linhagem Celular Tumoral , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Cães , Células HEK293 , Infecções por HIV/patologia , HIV-1/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Vírus da Influenza A/efeitos dos fármacos , Influenza Humana/patologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Pandemias , Pneumonia Viral/patologia , Ligação Proteica/genética , Transporte Proteico/efeitos dos fármacos , RNA Viral/genética , Receptor de Interferon alfa e beta/genética , Fator de Crescimento Transformador beta1/metabolismo , Células Vero , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Infecção por Zika virus/patologia
4.
Pharm Res ; 37(10): 194, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32918191

RESUMO

PURPOSE: We characterized three canine P-gp (cP-gp) deficient MDCKII cell lines. Their relevance for identifying efflux transporter substrates and predicting limitation of brain penetration were evaluated. In addition, we discuss how compound selection can be done in drug discovery by using these cell systems. METHOD: hMDR1, hBCRP-transfected, and non-transfected MDCKII ZFN cells (all with knock-down of endogenous cP-gp) were used for measuring permeability and efflux ratios for substrates. The compounds were also tested in MDR1_Caco-2 and BCRP_Caco-2, each with a double knock-out of BCRP/MRP2 or MDR1/MRP2 transporters respectively. Efflux results were compared between the MDCK and Caco-2 models. Furthermore, in vitro MDR1_ZFN efflux data were correlated with in vivo unbound drug brain-to-plasma partition coefficient (Kp,uu). RESULTS: MDR1 and BCRP substrates are correctly classified and robust transporter affinities with control substrates are shown. Cell passage mildly influenced mRNA levels of transfected transporters, but the transporter activity was proven stable for several years. The MDCK and Caco-2 models were in high consensus classifying same efflux substrates. Approx. 80% of enlisted substances were correctly predicted with the MDR1_ZFN model for brain penetration. CONCLUSION: cP-gp deficient MDCKII ZFN models are reliable tools to identify MDR1 and BCRP substrates and useful for predicting efflux liability for brain penetration.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Proteínas de Neoplasias/metabolismo , Farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Células CACO-2 , Permeabilidade da Membrana Celular , Dibenzocicloeptenos/farmacologia , Dicetopiperazinas/farmacologia , Cães , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Células Madin Darby de Rim Canino , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Prazosina/farmacocinética , Quinidina/farmacocinética , Quinolinas/farmacologia , Especificidade por Substrato , Transfecção
5.
Phys Rev Lett ; 125(8): 088102, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32909763

RESUMO

We perform a bidimensional Stokes experiment in an active cellular material: an autonomously migrating monolayer of Madin-Darby canine kidney epithelial cells flows around a circular obstacle within a long and narrow channel, involving an interplay between cell shape changes and neighbor rearrangements. Based on image analysis of tissue flow and coarse-grained cell anisotropy, we determine the tissue strain rate, cell deformation, and rearrangement rate fields, which are spatially heterogeneous. We find that the cell deformation and rearrangement rate fields correlate strongly, which is compatible with a Maxwell viscoelastic liquid behavior (and not with a Kelvin-Voigt viscoelastic solid behavior). The value of the associated relaxation time is measured as τ=70±15 min, is observed to be independent of obstacle size and division rate, and is increased by inhibiting myosin activity. In this experiment, the monolayer behaves as a flowing material with a Weissenberg number close to one which shows that both elastic and viscous effects can have comparable contributions in the process of collective cell migration.


Assuntos
Movimento Celular/fisiologia , Células Epiteliais/química , Células Epiteliais/citologia , Modelos Biológicos , Substâncias Viscoelásticas/química , Animais , Cães , Células Madin Darby de Rim Canino
6.
Viruses ; 12(9)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32883050

RESUMO

Until vaccines and effective therapeutics become available, the practical solution to transit safely out of the current coronavirus disease 19 (CoVID-19) lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of results, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected NHS patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. Therefore, this system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.


Assuntos
Inteligência Artificial , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Pneumonia Viral/virologia , Animais , Chlorocebus aethiops , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Cães , Humanos , Células Madin Darby de Rim Canino , Pandemias , Pneumonia Viral/diagnóstico , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Células Vero
7.
Int J Nanomedicine ; 15: 6503-6518, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922013

RESUMO

Objective: A non-lipolysis nanoemulsion (NNE) was designed to reduce the first-pass metabolism of raloxifene (RAL) by intestinal UDP-glucuronosyltransferases (UGTs) for increasing the oral absorption of RAL, coupled with in vitro and in vivo studies. Methods: In vitro stability of NNE was evaluated by lipolysis and the UGT metabolism system. The oral bioavailability of NNE was studied in rats and pigs. Finally, the absorption mechanisms of NNE were investigated by in situ single-pass intestinal perfusion (SPIP) in rats, Madin-Darby canine kidney (MDCK) cells model, and lymphatic blocking model. Results: The pre-NNE consisted of isopropyl palmitate, linoleic acid, Cremophor RH40, and ethanol in a weight ratio of 3.33:1.67:3:2. Compared to lipolysis nanoemulsion of RAL (RAL-LNE), the RAL-NNE was more stable in in vitro gastrointestinal buffers, lipolysis, and UGT metabolism system (p < 0.05). The oral bioavailability was significantly improved by the NNE (203.30%) and the LNE (205.89%) relative to the suspension group in rats. However, 541.28% relative bioavailability was achieved in pigs after oral NNE intake compared to the suspension and had two-fold greater bioavailability than the LNE (p < 0.05). The RAL-NNE was mainly absorbed in the jejunum and had high permeability at the intestine of rats. The results of both SPIP and MDCK cell models demonstrated that the RAL-NNE was absorbed via endocytosis mediated by caveolin and clathrin. The other absorption route, the lymphatic transport (cycloheximide as blocking agent), was significantly improved by the NNE compared with the LNE (p < 0.05). Conclusion: A NNE was successfully developed to reduce the first-pass metabolism of RAL in the intestine and enhance its lymphatic transport, thereby improving the oral bioavailability. Altogether, NNE is a promising carrier for the oral delivery of drugs with significant first-pass metabolism.


Assuntos
Absorção Fisico-Química , Emulsões/química , Lipólise , Nanopartículas/química , Cloridrato de Raloxifeno/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Transporte Biológico , Sobrevivência Celular , Cães , Emulsões/administração & dosagem , Feminino , Intestinos/fisiologia , Linfa/metabolismo , Células Madin Darby de Rim Canino , Masculino , Polietilenoglicóis , Ratos Sprague-Dawley , Tensoativos/química , Suínos
8.
Phys Rev Lett ; 125(3): 038003, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32745423

RESUMO

Experiments and theory have shown that cell monolayers and epithelial tissues exhibit solid-liquid and glass-liquid transitions. These transitions are biologically relevant to our understanding of embryonic development, wound healing, and cancer. Current models of confluent epithelia have focused on the role of cell shape, with less attention paid to cell extrusion, which is key for maintaining homeostasis in biological tissue. Here, we use a multiphase field model to study the solid-liquid transition in a confluent monolayer of deformable cells. Cell overlap is allowed and provides a way for modeling the precursor for extrusion. When cells overlap rather than deform, we find that the melting transition changes from continuous to first order like, and that there is an intermittent regime close to the transition, where solid and liquid states alternate over time. By studying the dynamics of five- and sevenfold disclinations in the hexagonal lattice formed by the cell centers, we observe that these correlate with spatial fluctuations in the cellular overlap, and that cell extrusion tends to initiate near fivefold disclinations.


Assuntos
Células Epiteliais/química , Células Epiteliais/citologia , Rim/química , Rim/citologia , Modelos Biológicos , Animais , Fenômenos Biofísicos , Movimento Celular/fisiologia , Forma Celular/fisiologia , Cães , Transição Epitelial-Mesenquimal , Células Madin Darby de Rim Canino , Transição de Fase
9.
BMC Infect Dis ; 20(1): 585, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762666

RESUMO

BACKGROUND: The polymerase chain reaction (PCR) is commonly used to detect viral pathogens because of its high sensitivity and specificity. However, conventional PCR methods cannot determine virus infectivity. Virus infectivity is conventionally examined with methods such as the plaque assay, even though such assays require several days. Long-range reverse-transcription quantitative PCR (RT-qPCR) has previously been suggested for the rapid assessment of RNA virus infectivity where the loss of infectivity is attributable to genomic fragmentation. METHODS: IAV was irradiated with 253.7 nm ultraviolet (UV) rays to induce genomic strand breaks that were confirmed by a full-length RT-PCR assay. The IAV was then subjected to plaque assay, conventional RT-qPCR and long-range RT-qPCR to examine the relationship between infectious titer and copy number. A simple linear regression analysis was performed to examine the correlation between the results of these assays. RESULTS: A long-range RT-qPCR assay was developed and validated for influenza A virus (IAV). Although only a few minutes of UV irradiation was required to completely inactivate IAV, genomic RNA remained detectable by the conventional RT-qPCR and the full-length RT-PCR for NS of viral genome following inactivation. A long-range RT-qPCR assay was then designed using RT-priming at the 3' termini of each genomic segment and subsequent qPCR of the 5' regions. UV-mediated IAV inactivation was successfully analyzed by the long-range RT-qPCR assay especially when targeting PA of the viral genome. This was also supported by the regression analysis that the long-range RT-qPCR is highly correlated with plaque assay (Adjusted R2 = 0.931, P = 0.000066). CONCLUSIONS: This study suggests that IAV infectivity can be predicted without the infectivity assays. The rapid detection of pathogenic IAV has, therefore, been achieved with this sensing technology.


Assuntos
Vírus da Influenza A/genética , Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Virulência/genética , Animais , Cães , Genoma Viral/genética , Genoma Viral/efeitos da radiação , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza A/efeitos da radiação , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/virologia , Estabilidade de RNA/efeitos da radiação , RNA Viral/genética , RNA Viral/efeitos da radiação , Raios Ultravioleta , Inativação de Vírus/efeitos da radiação
10.
Cell Rep ; 32(6): 108016, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32755598

RESUMO

The influenza virus hemagglutinin (HA) and coronavirus spike (S) protein mediate virus entry. HA and S proteins are heavily glycosylated, making them potential targets for carbohydrate binding agents such as lectins. Here, we show that the lectin FRIL, isolated from hyacinth beans (Lablab purpureus), has anti-influenza and anti-SARS-CoV-2 activity. FRIL can neutralize 11 representative human and avian influenza strains at low nanomolar concentrations, and intranasal administration of FRIL is protective against lethal H1N1 infection in mice. FRIL binds preferentially to complex-type N-glycans and neutralizes viruses that possess complex-type N-glycans on their envelopes. As a homotetramer, FRIL is capable of aggregating influenza particles through multivalent binding and trapping influenza virions in cytoplasmic late endosomes, preventing their nuclear entry. Remarkably, FRIL also effectively neutralizes SARS-CoV-2, preventing viral protein production and cytopathic effect in host cells. These findings suggest a potential application of FRIL for the prevention and/or treatment of influenza and COVID-19.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Fabaceae/química , Infecções por Orthomyxoviridae/tratamento farmacológico , Lectinas de Plantas/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Células A549 , Administração Intranasal , Animais , Antivirais/administração & dosagem , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Embrião de Galinha , Chlorocebus aethiops , Cães , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Lectinas de Plantas/administração & dosagem , Lectinas de Plantas/farmacologia , Ligação Proteica , Células Vero , Proteínas do Envelope Viral/metabolismo
11.
PLoS Pathog ; 16(8): e1008760, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32790753

RESUMO

Influenza A viruses (IAVs) remain a significant global health burden. Activation of the innate immune response is important for controlling early virus replication and spread. It is unclear how early IAV replication events contribute to immune detection. Additionally, while many cell types in the lung can be infected, it is not known if all cell types contribute equally to establish the antiviral state in the host. Here, we use single-cycle influenza A viruses (scIAVs) to characterize the early immune response to IAV in vitro and in vivo. We found that the magnitude of virus replication contributes to antiviral gene expression within infected cells prior to the induction of a global response. We also developed a scIAV that is only capable of undergoing primary transcription, the earliest stage of virus replication. Using this tool, we uncovered replication stage-specific responses in vitro and in vivo. Using several innate immune receptor knockout cell lines, we identify RIG-I as the predominant antiviral detector of primary virus transcription and amplified replication in vitro. Through a Cre-inducible reporter mouse, we used scIAVs expressing Cre-recombinase to characterize cell type-specific responses in vivo. Individual cell types upregulate unique sets of antiviral genes in response to both primary virus transcription and amplified replication. We also identified antiviral genes that are only upregulated in response to direct infection. Altogether, these data offer insight into the early mechanisms of antiviral gene activation during influenza A infection.


Assuntos
Células Epiteliais/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/imunologia , Replicação Viral , Células A549 , Animais , Antivirais/farmacologia , Proteína DEAD-box 58/metabolismo , Cães , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Células HEK293 , Humanos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia
12.
Nat Commun ; 11(1): 4320, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859916

RESUMO

In autosomal dominant polycystic kidney disease (ADPKD) multiple bilateral renal cysts gradually enlarge, leading to a decline in renal function. Transepithelial chloride secretion through cystic fibrosis transmembrane conductance regulator (CFTR) and TMEM16A (anoctamin 1) are known to drive cyst enlargement. Here we demonstrate that loss of Pkd1 increased expression of TMEM16A and CFTR and Cl- secretion in murine kidneys, with TMEM16A essentially contributing to cyst growth. Upregulated TMEM16A enhanced intracellular Ca2+ signaling and proliferation of Pkd1-deficient renal epithelial cells. In contrast, increase in Ca2+ signaling, cell proliferation and CFTR expression was not observed in Pkd1/Tmem16a double knockout mice. Knockout of Tmem16a or inhibition of TMEM16A in vivo by the FDA-approved drugs niclosamide and benzbromarone, as well as the TMEM16A-specific inhibitor Ani9 largely reduced cyst enlargement and abnormal cyst cell proliferation. The present data establish a therapeutic concept for the treatment of ADPKD.


Assuntos
Anoctamina-1/genética , Anoctamina-1/metabolismo , Cistos/metabolismo , Rim Policístico Autossômico Dominante/metabolismo , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Animais , Anoctamina-1/efeitos dos fármacos , Benzobromarona/farmacologia , Canais de Cálcio , Proliferação de Células , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística , Cistos/tratamento farmacológico , Cistos/genética , Modelos Animais de Doenças , Cães , Células Epiteliais/metabolismo , Humanos , Rim/metabolismo , Rim/patologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Knockout , Néfrons/metabolismo , Niclosamida/farmacologia , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/genética
13.
Int J Nanomedicine ; 15: 5181-5202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801685

RESUMO

Background: Combating infectious diseases caused by influenza virus is a major challenge due to its resistance to available drugs and vaccines, side effects, and cost of treatment. Nanomedicines are being developed to allow targeted delivery of drugs to attack specific cells or viruses. Materials and Methods: In this study, mesoporous silica nanoparticles (MSNs) functionalized with amino groups and loaded with natural prodrugs of shikimic acid (SH), quercetin (QR) or both were explored as a novel antiviral nanoformulations targeting the highly pathogenic avian influenza H5N1 virus. Also, the immunomodulatory effects were investigated in vitro tests and anti-inflammatory activity was determined in vivo using the acute carrageenan-induced paw edema rat model. Results: Prodrugs alone or the MSNs displayed weaker antiviral effects as evidenced by virus titers and plaque formation compared to nanoformulations. The MSNs-NH2-SH and MSNs-NH2-SH-QR2 nanoformulations displayed a strong virucidal by inactivating the H5N1 virus. They induced also strong immunomodulatory effects: they inhibited cytokines (TNF-α, IL-1ß) and nitric oxide production by approximately 50% for MSNs-NH2-SH-QR2 (containing both SH and QR). Remarkable anti-inflammatory effects were observed during in vivo tests in an acute carrageenan-induced rat model. Conclusion: Our preliminary findings show the potential of nanotechnology for the application of natural prodrug substances to produce a novel safe, effective, and affordable antiviral drug.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antivirais/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Nanopartículas/química , Pró-Fármacos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/imunologia , Antivirais/imunologia , Citocinas/metabolismo , Cães , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Edema/tratamento farmacológico , Edema/metabolismo , Fatores Imunológicos/imunologia , Fatores Imunológicos/farmacologia , Células Madin Darby de Rim Canino , Masculino , Camundongos , Quercetina/imunologia , Quercetina/farmacologia , Ratos , Ácido Chiquímico/imunologia , Ácido Chiquímico/farmacologia , Dióxido de Silício/química
14.
PLoS Pathog ; 16(8): e1008816, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853241

RESUMO

Influenza A viruses (IAVs) cause seasonal epidemics and occasional pandemics. Most pandemics occurred upon adaptation of avian IAVs to humans. This adaptation includes a hallmark receptor-binding specificity switch of hemagglutinin (HA) from avian-type α2,3- to human-type α2,6-linked sialic acids. Complementary changes of the receptor-destroying neuraminidase (NA) are considered to restore the precarious, but poorly described, HA-NA-receptor balance required for virus fitness. In comparison to the detailed functional description of adaptive mutations in HA, little is known about the functional consequences of mutations in NA in relation to their effect on the HA-NA balance and host tropism. An understudied feature of NA is the presence of a second sialic acid-binding site (2SBS) in avian IAVs and absence of a 2SBS in human IAVs, which affects NA catalytic activity. Here we demonstrate that mutation of the 2SBS of avian IAV H5N1 disturbs the HA-NA balance. Passaging of a 2SBS-negative H5N1 virus on MDCK cells selected for progeny with a restored HA-NA balance. These viruses obtained mutations in NA that restored a functional 2SBS and/or in HA that reduced binding of avian-type receptors. Importantly, a particular HA mutation also resulted in increased binding of human-type receptors. Phylogenetic analyses of avian IAVs show that also in the field, mutations in the 2SBS precede mutations in HA that reduce binding of avian-type receptors and increase binding of human-type receptors. Thus, 2SBS mutations in NA can drive acquisition of mutations in HA that not only restore the HA-NA balance, but may also confer increased zoonotic potential.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , Mutação , Neuraminidase/genética , Infecções por Orthomyxoviridae/virologia , Ácidos Siálicos/metabolismo , Replicação Viral , Substituição de Aminoácidos , Animais , Sítios de Ligação , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A/isolamento & purificação , Células Madin Darby de Rim Canino , Neuraminidase/química , Neuraminidase/metabolismo , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , Ligação Proteica
15.
PLoS One ; 15(8): e0237163, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764792

RESUMO

In bovine mammary glands, the ABCG2 transporter actively secretes xenobiotics into dairy milk. This can have significant implications when cattle are exposed to pesticide residues in feed. Recent studies indicate that the fungicide prochloraz activates the aryl hydrocarbon receptor (AhR) pathway, increasing bovine ABCG2 (bABCG2) gene expression and efflux activity. This could enhance the accumulation of bABCG2 substrates in dairy milk, impacting pesticide risk assessment. We therefore investigated whether 13 commonly used pesticides in Europe are inducers of AhR and bABCG2 activity. MDCKII cells expressing mammary bABCG2 were incubated with pesticides for up to 72 h. To reflect an in vivo situation, applied pesticide concentrations corresponded to the maximum residue levels (MRLs) permitted in bovine fat or muscle. AhR activation was ascertained through CYP1A mRNA expression and enzyme activity, measured by qPCR and 7-ethoxyresorufin-Ο-deethylase (EROD) assay, respectively. Pesticide-mediated increase of bABCG2 efflux activity was assessed using the Hoechst 33342 accumulation assay. For all assays, the known AhR-activating pesticide prochloraz served as a positive control, while the non-activating tolclofos-methyl provided the negative control. At 10-fold MRL concentrations, chlorpyrifos-methyl, diflufenican, ioxynil, rimsulfuron, and tebuconazole significantly increased CYP1A1 mRNA levels, CYP1A activity, and bABCG2 efflux activity compared to the vehicle control. In contrast, dimethoate, dimethomorph, glyphosate, iprodione, methiocarb and thiacloprid had no impact on AhR-mediated CYP1A1 mRNA levels, CYP1A activity or bABCG2 efflux. In conclusion, the MDCKII-bABCG2 cell model proved an appropriate tool for identifying AhR- and bABCG2-inducing pesticides. This provides an in vitro approach that could reduce the number of animals required in pesticide approval studies.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Alternativas aos Testes com Animais/métodos , Fungicidas Industriais/toxicidade , Receptores de Hidrocarboneto Arílico/agonistas , Testes de Toxicidade Crônica/métodos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/agonistas , Animais , Bovinos , Cães , Alemanha , Lactação/efeitos dos fármacos , Células Madin Darby de Rim Canino , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas Recombinantes/metabolismo
16.
PLoS One ; 15(8): e0237218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760143

RESUMO

Influenza is an infectious respiratory illness caused by influenza viruses. Despite yearly updates, the efficacy of influenza vaccines is significantly curtailed by the virus antigenic drift and antigenic shift. These constant changes to the influenza virus make-up also challenge the development of a universal flu vaccine, which requires conserved antigenic regions shared by influenza viruses of different subtypes. We propose that it is possible to bypass these challenges by the development of an influenza vaccine based on conserved proteins delivered in an adjuvanted nanoparticle system. In this study, we generated influenza nanoparticle constructs using trimethyl chitosan nanoparticles (TMC nPs) as the carrier of recombinant influenza hemagglutinin subunit 2 (HA2) and nucleoprotein (NP). The purified HA2 and NP recombinant proteins were encapsulated into TMC nPs to form HA2-TMC nPs and NP-TMC nPs, respectively. Primary human intranasal epithelium cells (HNEpCs) were used as an in vitro model to measure immunity responses. HA2-TMC nPs, NP-TMC nPs, and HA2-NP-TMC nPs (influenza nanoparticle constructs) showed no toxicity in HNEpCs. The loading efficiency of HA2 and NP into the TMC nPs was 97.9% and 98.5%, respectively. HA2-TMC nPs and NP-TMC nPs more efficiently delivered HA2 and NP proteins to HNEpCs than soluble HA2 and NP proteins alone. The induction of various cytokines and chemokines was more evident in influenza nanoparticle construct-treated HNEpCs than in soluble protein-treated HNEpCs. In addition, soluble factors secreted by influenza nanoparticle construct-treated HNEpCs significantly induced MoDCs maturation markers (CD80, CD83, CD86 and HLA-DR), as compared to soluble factors secreted by protein-treated HNEpCs. HNEpCs treated with the influenza nanoparticle constructs significantly reduced influenza virus replication in an in vitro challenge assay. The results indicate that TMC nPs can be used as influenza vaccine adjuvants and carriers capable of delivering HA2 and NP proteins to HNEpCs.


Assuntos
Adjuvantes Imunológicos/farmacologia , Quitosana/farmacologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/farmacologia , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Animais , Linhagem Celular , Células Cultivadas , Quitosana/administração & dosagem , Cães , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/farmacologia , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Células Madin Darby de Rim Canino , Nanopartículas/administração & dosagem , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas de Ligação a RNA/administração & dosagem , Proteínas de Ligação a RNA/farmacologia , Proteínas do Core Viral/administração & dosagem , Proteínas do Core Viral/farmacologia
17.
Viruses ; 12(6)2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599823

RESUMO

The respiratory Influenza A Viruses (IAVs) and emerging zoonotic viruses such as Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pose a significant threat to human health. To accelerate our understanding of the host-pathogen response to respiratory viruses, the use of more complex in vitro systems such as normal human bronchial epithelial (NHBE) cell culture models has gained prominence as an alternative to animal models. NHBE cells were differentiated under air-liquid interface (ALI) conditions to form an in vitro pseudostratified epithelium. The responses of well-differentiated (wd) NHBE cells were examined following infection with the 2009 pandemic Influenza A/H1N1pdm09 strain or following challenge with the dsRNA mimic, poly(I:C). At 30 h postinfection with H1N1pdm09, the integrity of the airway epithelium was severely impaired and apical junction complex damage was exhibited by the disassembly of zona occludens-1 (ZO-1) from the cell cytoskeleton. wdNHBE cells produced an innate immune response to IAV-infection with increased transcription of pro- and anti-inflammatory cytokines and chemokines and the antiviral viperin but reduced expression of the mucin-encoding MUC5B, which may impair mucociliary clearance. Poly(I:C) produced similar responses to IAV, with the exception of MUC5B expression which was more than 3-fold higher than for control cells. This study demonstrates that wdNHBE cells are an appropriate ex-vivo model system to investigate the pathogenesis of respiratory viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/virologia , Mucosa Respiratória/citologia , Mucosa Respiratória/virologia , Animais , Brônquios/citologia , Brônquios/virologia , Células Cultivadas , Quimiocinas/metabolismo , Citocinas/metabolismo , Cães , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/epidemiologia , Junções Intercelulares , Células Madin Darby de Rim Canino , Modelos Biológicos , Mucina-5AC/metabolismo , Pandemias , Cultura de Vírus
18.
Nat Commun ; 11(1): 3418, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647286

RESUMO

The emergence and spread of antiviral drug-resistant viruses have been a worldwide challenge and a great concern for patient care. We report A4 antibody specifically recognizing and binding to the mutant I223R/H275Y neuraminidase and prove the applicability of A4 antibody for direct detection of antiviral multidrug-resistant viruses in various sensing platforms, including naked-eye detection, surface-enhanced Raman scattering-based immunoassay, and lateral flow system. The development of the A4 antibody enables fast, simple, and reliable point-of-care assays of antiviral multidrug-resistant influenza viruses. In addition to current influenza virus infection testing methods that do not provide information on the antiviral drug-resistance of the virus, diagnostic tests for antiviral multidrug-resistant viruses will improve clinical judgment in the treatment of influenza virus infections, avoid the unnecessary prescription of ineffective drugs, and improve current therapies.


Assuntos
Anticorpos Antivirais/imunologia , Resistência a Múltiplos Medicamentos/imunologia , Farmacorresistência Viral/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Mutação/genética , Neuraminidase/genética , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/química , Afinidade de Anticorpos/imunologia , Antígenos Virais/metabolismo , Líquidos Corporais/virologia , Análise Mutacional de DNA , Cães , Epitopos/química , Epitopos/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H3N2/enzimologia , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , Imagem Óptica , Ligação Proteica , Análise Espectral Raman
19.
Euro Surveill ; 25(25)2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32613937

RESUMO

The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.


Assuntos
Galinhas/imunologia , Coronavirus/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Células Madin Darby de Rim Canino , Receptores Virais/metabolismo , Cultura de Vírus/métodos , Replicação Viral , Animais , Betacoronavirus , Linhagem Celular , Galinhas/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Cães , Ovos , Humanos , Pandemias , Pneumonia Viral , Síndrome Respiratória Aguda Grave
20.
J Virol ; 94(19)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32699094

RESUMO

The newly emerged human coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a pandemic of respiratory illness. Current evidence suggests that severe cases of SARS-CoV-2 are associated with a dysregulated immune response. However, little is known about how the innate immune system responds to SARS-CoV-2. In this study, we modeled SARS-CoV-2 infection using primary human airway epithelial (pHAE) cultures, which are maintained in an air-liquid interface. We found that SARS-CoV-2 infects and replicates in pHAE cultures and is directionally released on the apical, but not basolateral, surface. Transcriptional profiling studies found that infected pHAE cultures had a molecular signature dominated by proinflammatory cytokines and chemokine induction, including interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), and CXCL8, and identified NF-κB and ATF-4 as key drivers of this proinflammatory cytokine response. Surprisingly, we observed a complete lack of a type I or III interferon (IFN) response to SARS-CoV-2 infection. However, pretreatment and posttreatment with type I and III IFNs significantly reduced virus replication in pHAE cultures that correlated with upregulation of antiviral effector genes. Combined, our findings demonstrate that SARS-CoV-2 does not trigger an IFN response but is sensitive to the effects of type I and III IFNs. Our studies demonstrate the utility of pHAE cultures to model SARS-CoV-2 infection and that both type I and III IFNs can serve as therapeutic options to treat COVID-19 patients.IMPORTANCE The current pandemic of respiratory illness, COVID-19, is caused by a recently emerged coronavirus named SARS-CoV-2. This virus infects airway and lung cells causing fever, dry cough, and shortness of breath. Severe cases of COVID-19 can result in lung damage, low blood oxygen levels, and even death. As there are currently no vaccines approved for use in humans, studies of the mechanisms of SARS-CoV-2 infection are urgently needed. Our research identifies an excellent system to model SARS-CoV-2 infection of the human airways that can be used to test various treatments. Analysis of infection in this model system found that human airway epithelial cell cultures induce a strong proinflammatory cytokine response yet block the production of type I and III IFNs to SARS-CoV-2. However, treatment of airway cultures with the immune molecules type I or type III interferon (IFN) was able to inhibit SARS-CoV-2 infection. Thus, our model system identified type I or type III IFN as potential antiviral treatments for COVID-19 patients.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Células Epiteliais/imunologia , Interferon Tipo I/imunologia , Interferons/imunologia , Pneumonia Viral/imunologia , Animais , Betacoronavirus/fisiologia , Brônquios/citologia , Brônquios/imunologia , Brônquios/virologia , Linhagem Celular , Células Cultivadas , Quimiocinas/imunologia , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Citocinas/imunologia , Cães , Células Epiteliais/virologia , Humanos , Pulmão/citologia , Pulmão/imunologia , Pulmão/virologia , Células Madin Darby de Rim Canino , Pandemias , Pneumonia Viral/virologia , Células Vero , Replicação Viral
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