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1.
J Virol ; 91(10)2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28250124

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is a bunyavirus causing severe hemorrhagic fever disease in humans, with high mortality rates. The requirement of a high-containment laboratory and the lack of an animal model hampered the study of the immune response and protection of vaccine candidates. Using the recently developed interferon alpha receptor knockout (IFNAR-/-) mouse model, which replicates human disease, we investigated the immunogenicity and protection of two novel CCHFV vaccine candidates: a DNA vaccine encoding a ubiquitin-linked version of CCHFV Gc, Gn, and N and one using transcriptionally competent virus-like particles (tc-VLPs). In contrast to most studies that focus on neutralizing antibodies, we measured both humoral and cellular immune responses. We demonstrated a clear and 100% efficient preventive immunity against lethal CCHFV challenge with the DNA vaccine. Interestingly, there was no correlation with the neutralizing antibody titers alone, which were higher in the tc-VLP-vaccinated mice. However, the animals with a lower neutralizing titer, but a dominant cell-mediated Th1 response and a balanced Th2 response, resisted the CCHFV challenge. Moreover, we found that in challenged mice with a Th1 response (immunized by DNA/DNA and boosted by tc-VLPs), the immune response changed to Th2 at day 9 postchallenge. In addition, we were able to identify new linear B-cell epitope regions that are highly conserved between CCHFV strains. Altogether, our results suggest that a predominantly Th1-type immune response provides the most efficient protective immunity against CCHFV challenge. However, we cannot exclude the importance of the neutralizing antibodies as the surviving immunized mice exhibited substantial amounts of them.IMPORTANCE Crimean-Congo hemorrhagic fever virus (CCHFV) is responsible for hemorrhagic diseases in humans, with a high mortality rate. There is no FDA-approved vaccine, and there are still gaps in our knowledge of the immune responses to infection. The recently developed mouse models mimic human CCHF disease and are useful to study the immunogenicity and the protection by vaccine candidates. Our study shows that mice vaccinated with a specific DNA vaccine were fully protected. Importantly, we show that neutralizing antibodies are not sufficient for protection against CCHFV challenge but that an extra Th1-specific cellular response is required. Moreover, we describe the identification of five conserved B-cell epitopes, of which only one was previously known, that could be of great importance for the development of diagnostics tools and the improvement of vaccine candidates.


Assuntos
Proteínas do Capsídeo/imunologia , Febre Hemorrágica da Crimeia/imunologia , Febre Hemorrágica da Crimeia/prevenção & controle , Plasmídeos/genética , Vacinas de DNA/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Neutralizantes/sangue , Proteínas do Capsídeo/genética , Modelos Animais de Doenças , Epitopos de Linfócito B/imunologia , Vírus da Febre Hemorrágica da Crimeia-Congo/química , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/virologia , Humanos , Imunidade Celular , Imunização , Imunogenicidade da Vacina , Interferon-alfa/deficiência , Interferon-alfa/genética , Camundongos , Camundongos Knockout , Plasmídeos/administração & dosagem , Células Th1 , Células Th2 , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Proteínas do Envelope Viral/genética
2.
J Virol ; 85(15): 7766-74, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21632768

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) causes viral hemorrhagic fever with high case-fatality rates and is geographically widely distributed. Due to the requirement for a biosafety level 4 (BSL-4) laboratory and the lack of an animal model, knowledge of the viral pathogenesis is limited. Crimean-Congo hemorrhagic fever (CCHF) is characterized by hemorrhage and vascular permeability, indicating the involvement of endothelial cells (ECs). The interplay between ECs and CCHFV is therefore important for understanding the pathogenesis of CCHF. In a previous study, we found that CCHFV-infected monocyte-derived dendritic cells (moDCs) activated ECs; however, the direct effect of CCHFV on ECs was not investigated. Here, we report that ECs are activated upon infection, as demonstrated by upregulation of mRNA levels for E-selectin, vascular cell adhesion molecule 1 (VCAM1), and intercellular adhesion molecule 1 (ICAM1). Protein levels and cell surface expression of ICAM1 responded in a dose-dependent manner to increasing CCHFV titers with concomitant increase in leukocyte adhesion. Furthermore, we examined vascular endothelial (VE) cadherin in CCHFV-infected ECs by different approaches. Infected ECs released higher levels of interleukin 6 (IL-6) and IL-8; however, stimulation of resting ECs with supernatants derived from infected ECs did not result in increased ICAM1 expression. Interestingly, the moDC-mediated activation of ECs was abrogated by addition of neutralizing tumor necrosis factor alpha (TNF-α) antibody to moDC supernatants, thereby identifying this soluble mediator as the key cytokine causing EC activation. We conclude that CCHFV can exert both direct and indirect effects on ECs.


Assuntos
Endotélio Vascular/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/fisiologia , Animais , Antígenos CD/metabolismo , Western Blotting , Caderinas/metabolismo , Células Cultivadas , Chlorocebus aethiops , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Reação em Cadeia da Polimerase , Células Vero
3.
J Virol ; 84(16): 8275-86, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20519402

RESUMO

The spread of the recently emerged, highly pathogenic H5N1 avian influenza virus has raised concern. Preclinical studies suggest that passive immunotherapy could be a new form of treatment for H5N1 virus infection. Here, a neutralizing monoclonal antibody (MAb) against the hemagglutinin (HA) of the influenza A/chicken/Hatay/2004 H5N1 virus, MAb 9F4, was generated and characterized. MAb 9F4 binds both the denatured and native forms of HA. It was shown to recognize the HA proteins of three heterologous strains of H5N1 viruses belonging to clades 1, 2.1, and 2.2, respectively. By use of lentiviral pseudotyped particles carrying HA on the surface, MAb 9F4 was shown to effectively neutralize the homologous strain, Hatay04, and another clade 1 strain, VN04, at a neutralization titer of 8 ng/ml. Furthermore, MAb 9F4 also neutralized two clade 2 viruses at a neutralizing titer of 40 ng/ml. The broad cross-neutralizing activity of MAb 9F4 was confirmed by its ability to neutralize live H5N1 viruses of clade 2.2.2. Epitope-mapping analysis revealed that MAb 9F4 binds a previously uncharacterized epitope below the globular head of the HA1 subunit. Consistently, this epitope is well conserved among the different clades of H5N1 viruses. MAb 9F4 does not block the interaction between HA and its receptor but prevents the pH-mediated conformational change of HA. MAb 9F4 was also found to be protective, both prophylactically and therapeutically, against a lethal viral challenge of mice. Taken together, our results showed that MAb 9F4 is a neutralizing MAb that binds a novel and well-conserved epitope in the HA1 subunit of H5N1 viruses.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/isolamento & purificação , Anticorpos Antivirais/uso terapêutico , Peso Corporal , Sequência Conservada , Proteção Cruzada , Reações Cruzadas , Mapeamento de Epitopos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/prevenção & controle , Análise de Sobrevida , Internalização do Vírus/efeitos dos fármacos
4.
J Gen Virol ; 91(Pt 6): 1473-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20164263

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) poses a great threat to public health due to its high mortality, transmission and geographical distribution. To date, there is no vaccine or specific treatment available and the knowledge regarding its pathogenesis is highly limited. Using a small-animal model system, this study showed that adult mice missing the type I interferon (IFN) receptor (IFNAR(-/-)) were susceptible to CCHFV and developed an acute disease with fatal outcome. In contrast, infection of wild-type mice (129 Sv/Ew) was asymptomatic. Viral RNA was found in all analysed organs of the infected mice, but the amount of CCHFV RNA was significantly higher in the IFNAR(-/-) mice than in the wild-type mice. Furthermore, the liver of IFNAR(-/-) mice was enlarged significantly, showing that IFN is important for limiting virus spread and protecting against liver damage in mice.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Vírus da Febre Hemorrágica da Crimeia-Congo/patogenicidade , Febre Hemorrágica da Crimeia/imunologia , Febre Hemorrágica da Crimeia/mortalidade , Receptor de Interferon alfa e beta/deficiência , Estruturas Animais/virologia , Animais , Feminino , Febre Hemorrágica da Crimeia/patologia , Febre Hemorrágica da Crimeia/virologia , Camundongos , Camundongos Knockout , Análise de Sobrevida
5.
J Med Virol ; 82(3): 467-75, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20087939

RESUMO

The non-structural protein NS1 of the influenza A virus is a good target for the development of diagnostic assays. In this study, three NS1 monoclonal antibodies (mAbs) were generated by using recombinant NS1 protein of H5N1 virus and found to bind both the native and denatured forms of NS1. Two of the mAbs, 6A4 and 2H6, bind NS1 of three different strains of influenza A virus, namely H1N1, H3N2, and H5N1. Epitope mapping revealed that residues 42-53 of H5N1 NS1 are essential for the interaction with both mAbs. Between the three strains, there is only one amino acid difference in this domain, which is consistent with the observed cross-reactivities. On the other hand, mAb 1G1 binds to residues 206-215 of H5N1 NS1 and does not bind NS1 of H1N1 or H3N2. Furthermore, all three mAbs detected NS1 proteins expressed in virus infected MDCK cells and indirect immunofluorescence staining with mAbs 6A4 and 2H6 provided an alternative method for viral titer determination. Quantifying the numbers of fluorescent foci units yielded viral titers for three different isolates of H5N1 virus that are highly comparable to that obtained by observing cytopathic effect induced by virus infection. Importantly, this alternative method yields results at 1 day post-infection while the conventional method using cytopathic effect yields results at 3 days post-infection. The results showed that this new panel of NS1 antibodies can detect NS1 protein expressed during viral infection and can be used for fast and easy titration of influenza A virus. J. Med. Virol. 82:467-475, 2010. (c) 2010 Wiley-Liss, Inc.


Assuntos
Anticorpos Antivirais , Técnicas de Laboratório Clínico/métodos , Vírus da Influenza A/classificação , Vírus da Influenza A/isolamento & purificação , Influenza Humana/diagnóstico , Proteínas não Estruturais Virais/imunologia , Animais , Anticorpos Monoclonais , Linhagem Celular , Efeito Citopatogênico Viral , Cães , Mapeamento de Epitopos , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Vírus da Influenza A/imunologia , Fatores de Tempo , Virologia/métodos
6.
Acta Vet Scand ; 60(1): 26, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29716621

RESUMO

BACKGROUND: Tularemia is a zoonosis caused by the bacterium Francisella tularensis. It has a wide host range, which includes mammals, birds and invertebrates. F. tularensis has often been isolated from various species of small rodents, but the pathology in naturally infected wild rodent species has rarely been reported. CASE PRESENTATION: Herein, we describe the pathology of tularemia in two naturally infected wild yellow-necked mice (Apodemus flavicollis). To visualize F. tularensis subsp. holarctica, indirect immunofluorescence and immunohistochemistry were applied on tissue sections. Real time polymerase chain reaction detected the bacterium in samples from liver and spleen in both mice. The only finding at necropsy was splenomegaly in one of the mice. Histological examination revealed necrotic foci in the liver associated with mild inflammation in both mice. Immunohistochemistry and indirect immunofluorescence showed bacteria disseminated in many organs, in the cytoplasm of macrophages, and intravascularly. CONCLUSIONS: The two yellow-necked mice died of an acute disease caused by tularemic infection disseminated to many organs. Further investigations of naturally infected small rodents are important to better understand the variability in pathological presentation caused by infection by F. tularensis subsp. holarctica, as well to elucidate the importance of small rodents as transmitters and/or reservoirs.


Assuntos
Francisella tularensis/isolamento & purificação , Murinae , Doenças dos Roedores/patologia , Tularemia/veterinária , Animais , Fígado/microbiologia , Masculino , Doenças dos Roedores/microbiologia , Baço/microbiologia , Suécia , Tularemia/microbiologia , Tularemia/patologia
7.
Antiviral Res ; 73(3): 219-27, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17112601

RESUMO

The severe acute respiratory syndrome coronavirus (SARS CoV) genome has 14 potential open reading frames (ORFs). The first ORF is translated from the full-length genomic mRNA while the remaining ORFs are translated from eight subgeomic RNAs (sgRNAs). In this study, we designed small interference RNAs (siRNAs) targeting sgRNA 2, 3 and 7 and tested their efficiency and specificity in silencing the protein translated from the targeted sgRNA. Our results demonstrated that siRNA 7 could inhibit sgRNA 7, which showed 19/19 nucleotides (nt) matching, and sgRNA 8, which showed 18/19 nt matching; but, it did not inhibit the full-length genomic mRNA which showed 17/19 nt matching. Overall, each of the siRNAs can inhibit the targeted sgRNA without affecting the full-length genomic mRNA or the other sgRNAs that showed mismatch of two or more nt. Thus, siRNA could be designed so as to knockdown the expression of viral protein(s) from a targeted sgRNA during viral infection, thereby allowing the contribution of individual viral proteins to viral infection to be delineated. When Vero E6 cells expressing siRNA 2, 3 or 7 were infected with SARS-CoV, a significant reduction in the yield of progeny virus was observed. Indirect immunofluorescence assays showed that in the infected cells expressing each of the siRNAs, there was aspecific silencing of S, 3a and 7a, respectively, but the expression of nucleocapsid protein was not affected. Thus, our data suggests that the accessory proteins, i.e. 3a and 7a, could play an important role during the replication cycle of the SARS-CoV.


Assuntos
RNA Interferente Pequeno/genética , Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Proteínas Virais/genética , Replicação Viral/genética , Animais , Chlorocebus aethiops , Imunofluorescência/métodos , RNA Mensageiro/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Síndrome Respiratória Aguda Grave/terapia , Síndrome Respiratória Aguda Grave/virologia , Especificidade por Substrato , Células Vero , Proteínas da Matriz Viral/biossíntese , Proteínas da Matriz Viral/genética , Proteínas Virais/biossíntese
8.
FEBS Lett ; 580(16): 3799-803, 2006 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-16781713

RESUMO

A synthetic peptide corresponding to amino acids (aa) 15-28 of the severe acute respiratory syndrome coronavirus (SARS-CoV) 3a protein was used to raise polyclonal antibodies in rabbits. This anti-3a N-terminal antibody could detect 3a protein in infected cells, as did an anti-3a C-terminal antibody previously described. The latter targeted the C-terminal cytoplasmic domain of 3a (aa 134-274). The anti-3a N-terminal antibody could detect intracellular 3a as well as 3a expressed on the cell surface. Interestingly, only the anti-3a N-terminal antibody can inhibit SARS-CoV propagation in Vero E6 culture although the binding affinity of the anti-3a N-terminal antibody was lower than the anti-3a C-terminal antibody.


Assuntos
Aminoácidos/imunologia , Anticorpos Antivirais/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Proteínas Virais/química , Proteínas Virais/imunologia , Animais , Sítios de Ligação de Anticorpos , Células COS , Chlorocebus aethiops , Epitopos/química , Epitopos/imunologia , Humanos , Testes de Neutralização , Estrutura Terciária de Proteína , Coelhos , Proteínas do Envelope Viral , Proteínas Viroporinas
9.
Microbes Infect ; 13(2): 179-88, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21035562

RESUMO

The severe acute respiratory syndrome coronavirus (SARS-CoV) 8b protein, which is not expressed by other known coronaviruses, can down-regulate the envelope (E) protein via a proteasome-dependent pathway. Here, we showed that the down-regulation of E is not dependent on the lysine residues on 8b and the reduction of polyubiquitination of E mutants is not correlated with their down-regulation by 8b, suggesting an ubiquitin-independent proteasome pathway is involved. A time-course study revealed that 8b was expressed at late-stages of SARS-CoV infection. By using Vero E6 cells stably expressing green fluorescence protein-tagged 8b, ectopic expression of 8b was shown to significantly reduce the production of progeny virus and down-regulate E expression. Taken together, these results suggest that 8b negatively modulates virus replication by down-regulating E via an ubiquitin-independent proteasome pathway.


Assuntos
Regulação para Baixo , Complexo de Endopeptidases do Proteassoma/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Replicação Viral/genética , Animais , Chlorocebus aethiops , Infecções por Coronavirus/metabolismo , Regulação Viral da Expressão Gênica , Técnicas de Inativação de Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Mutagênese Sítio-Dirigida , Estabilidade Proteica , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , Ubiquitina/metabolismo , Ubiquitinação/genética , Células Vero , Proteínas Viroporinas
10.
PLoS One ; 6(5): e19436, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21637748

RESUMO

BACKGROUND: 9b is an accessory protein of the SARS-CoV. It is a small protein of 98 amino acids and its structure has been solved recently. 9b is known to localize in the extra-nuclear region and has been postulated to possess a nuclear export signal (NES), however the role of NES in 9b functioning is not well understood. PRINCIPAL FINDINGS/METHODOLOGY: In this report, we demonstrate that 9b in the absence of any nuclear localization signal (NLS) enters the nucleus by passive transport. Using various cell cycle inhibitors, we have shown that the nuclear entry of 9b is independent of the cell cycle. Further, we found that 9b interacts with the cellular protein Crm1 and gets exported out of the nucleus using an active NES. We have also revealed that this NES activity influences the half-life of 9b and affects host cell death. We found that an export signal deficient SARS-CoV 9b protein induces apoptosis in transiently transfected cells and showed elevated caspase-3 activity. CONCLUSION/SIGNIFICANCE: Here, we showed that nuclear shuttling of 9b and its interaction with Crm1 are essential for the proper degradation of 9b and blocking the nuclear export of this protein induces apoptosis. This phenomenon may be critical in providing a novel role to the 9b accessory protein of SARS-CoV.


Assuntos
Apoptose , Núcleo Celular/metabolismo , Carioferinas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , Proteínas Virais/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Ciclo Celular , Chlorocebus aethiops , Difusão , Espaço Intracelular/metabolismo , Modelos Biológicos , Sinais de Exportação Nuclear , Sinais de Localização Nuclear/metabolismo , Processamento de Proteína Pós-Traducional , Transporte Proteico , Transfecção , Células Vero , Proteína Exportina 1
11.
Virology ; 395(1): 1-9, 2009 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-19800091

RESUMO

Nitric oxide is an important molecule playing a key role in a broad range of biological process such as neurotransmission, vasodilatation and immune responses. While the anti-microbiological properties of nitric oxide-derived reactive nitrogen intermediates (RNI) such as peroxynitrite, are known, the mechanism of these effects are as yet poorly studied. Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) belongs to the family Coronaviridae, was first identified during 2002-2003. Mortality in SARS patients ranges from between 6 to 55%. We have previously shown that nitric oxide inhibits the replication cycle of SARS-CoV in vitro by an unknown mechanism. In this study, we have further investigated the mechanism of the inhibition process of nitric oxide against SARS-CoV. We found that peroxynitrite, an intermediate product of nitric oxide in solution formed by the reaction of NO with superoxide, has no effect on the replication cycle of SARS-CoV, suggesting that the inhibition is either directly effected by NO or a derivative other than peroxynitrite. Most interestingly, we found that NO inhibits the replication of SARS-CoV by two distinct mechanisms. Firstly, NO or its derivatives cause a reduction in the palmitoylation of nascently expressed spike (S) protein which affects the fusion between the S protein and its cognate receptor, angiotensin converting enzyme 2. Secondly, NO or its derivatives cause a reduction in viral RNA production in the early steps of viral replication, and this could possibly be due to an effect on one or both of the cysteine proteases encoded in Orf1a of SARS-CoV.


Assuntos
Glicoproteínas de Membrana/metabolismo , Óxido Nítrico/farmacologia , RNA Viral/biossíntese , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Proteínas do Envelope Viral/metabolismo , Replicação Viral , Animais , Chlorocebus aethiops , Humanos , Lipoilação , Ácido Peroxinitroso/farmacologia , RNA Viral/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus , Células Vero
12.
Eur J Immunol ; 36(10): 2649-57, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16955520

RESUMO

Reactive nitrogen intermediates (RNI), like nitric oxide (NO) and peroxynitrite, have antiviral effects against certain viruses. Hantaviruses, like other members of the Bunyaviridae family, have previously not been shown to be sensitive to RNI. In this study, we compared the effects of NO and peroxynitrite on hantavirus replication and free mature virions in vitro, and of inducible nitric oxide synthase (iNOS) in hantavirus-infected suckling mice. The NO-generating compound S-nitroso-N-acetylpenicillamine (SNAP), as well as cytokine-induced NO, strongly inhibited hantavirus replication in Vero E6 cells, while pretreatment of free virions with SNAP only had a limited effect on their viability. In contrast, 3-morpholinosydnonimine hydrochloride (SIN-1), a peroxynitrite donor, inhibited virus replication only to a very low extent in vitro, but pretreatment of virus with SIN-1 led to a considerably lowered viability of the virions. Infections of various human cell types per se did not induce NO production. The viral titers in iNOS(-/-) mice were higher compared to the controls, suggesting that NO inhibits hantavirus replication in vivo. In conclusion, we show that NO has strong antiviral effects on hantavirus replication, and peryoxynitrite on mature free virions, suggesting that different RNI can have different effects on various parts of the replication cycle for the same virus.


Assuntos
Antivirais/farmacologia , Infecções por Hantavirus/metabolismo , Óxido Nítrico/farmacologia , Orthohantavírus/efeitos dos fármacos , Ácido Peroxinitroso/farmacologia , Vírion/efeitos dos fármacos , Animais , Western Blotting , Encéfalo/virologia , Células Cultivadas , Chlorocebus aethiops , Orthohantavírus/fisiologia , Infecções por Hantavirus/imunologia , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , S-Nitroso-N-Acetilpenicilamina/farmacologia , Células Vero , Replicação Viral/efeitos dos fármacos
13.
J Virol ; 79(3): 1966-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15650225

RESUMO

Nitric oxide (NO) is an important signaling molecule between cells which has been shown to have an inhibitory effect on some virus infections. The purpose of this study was to examine whether NO inhibits the replication cycle of the severe acute respiratory syndrome coronavirus (SARS CoV) in vitro. We found that an organic NO donor, S-nitroso-N-acetylpenicillamine, significantly inhibited the replication cycle of SARS CoV in a concentration-dependent manner. We also show here that NO inhibits viral protein and RNA synthesis. Furthermore, we demonstrate that NO generated by inducible nitric oxide synthase, an enzyme that produces NO, inhibits the SARS CoV replication cycle.


Assuntos
Óxido Nítrico/farmacologia , S-Nitroso-N-Acetilpenicilamina/farmacologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Chlorocebus aethiops , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Células Vero
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