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[PMID]:29458556
[Au] Autor:Abdel-Moneim AS; Soliman MS; Kamel MM; El-Kholy AA
[Ad] Endereço:1​Microbiology Department, College of Medicine, Taif University, Al-Taif 21944, Saudi Arabia.
[Ti] Título:Sequence analysis of the G gene of hRSVA ON1 genotype from Egyptian children with acute respiratory tract infections.
[So] Source:J Med Microbiol;67(3):387-391, 2018 Mar.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Human respiratory syncytial virus causes severe lower respiratory tract infection in neonates and children. Genotype ON1, with duplication of 72-nt in the G gene, was first detected in Canada and then recorded in other countries. In the current study, we describe the first detection of the ON1 genotype among children in Egypt in 2014/2015. Sequence analysis of the full-attachment G gene revealed that the majority of the strains examined were related to the ON1 genotype and only one sample related to N1 genotype. The Egyptian ON1 strains showed unique non-silent mutations in addition to variable mutations near the antigenic sites in comparison to the original ON1 ancestor strain. Continuous surveillance of hRSV regionally and globally is needed to understand the evolutionary mechanisms and strategies adopted by hRSV and their inducers for better adaption to the host.
[Mh] Termos MeSH primário: Infecções por Vírus Respiratório Sincicial/virologia
Vírus Sincicial Respiratório Humano/genética
Infecções Respiratórias/virologia
Proteínas Virais de Fusão/genética
[Mh] Termos MeSH secundário: Canadá/epidemiologia
Pré-Escolar
Egito/epidemiologia
Evolução Molecular
Feminino
Genótipo
Seres Humanos
Lactente
Masculino
Mutação
Nasofaringe/virologia
Filogenia
Infecções por Vírus Respiratório Sincicial/epidemiologia
Vírus Sincicial Respiratório Humano/isolamento & purificação
Infecções Respiratórias/epidemiologia
Alinhamento de Sequência
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (G glycoprotein, Respiratory syncytial virus); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000699


  2 / 3427 MEDLINE  
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[PMID]:28463659
[Au] Autor:Kosutic-Gulija T; Slovic A; Ljubin-Sternak S; Mlinaric-Galinovic G; Forcic D
[Ad] Endereço:1​Centre for Research and Knowledge Transfer in Biotechnology, University of Zagreb, Zagreb, Croatia.
[Ti] Título:Genetic analysis of human parainfluenza virus type 3 obtained in Croatia, 2011-2015.
[So] Source:J Med Microbiol;66(4):502-510, 2017 Apr.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: This study investigated the HPIV3 circulating strains in Croatia and whether the other parts of HPIV3 genome (F gene and HN 582 nucleotides fragment) could be equally suitable for genetic and phylogenetic analysis. METHODOLOGY: Clinical materials were collected in period 2011-2015 from children suffering from respiratory illnesses. In positive HPIV3 samples viral genome was partially amplified and sequenced for HN and F genes. Obtained sequences were analysed by phylogenetic analysis and genetic characterization was performed. RESULTS: All samples from this study belonged to subcluster C and over a short period of time, genetic lineage C3a gained prevalence over the other C genetic lineages, from 39 % in 2011 to more than 90 % in 2013 and 2014. Phylogenetic classifications of HPIV3 based on the entire HN gene, HN 582 nt fragment and entire fusion (F) gene showed identical classification results for Croatian strains and the reference strains. Molecular analysis of the F and HN glycoproteins, showed their similar nucleotide diversity (Fcds P=0.0244 and HNcds P=0.0231) and similar Ka/Ks ratios (F Ka/Ks=0.0553 and HN Ka/Ks=0.0428). Potential N-glycosylation sites, cysteine residues and antigenic sites are generally strongly conserved in HPIV3 glycoproteins from both our and the reference samples. CONCLUSION: The HPIV3 subclaster C3 (genetic lineage C3a) became the most detected circulating HPIV3 strain in Croatia. The results indicated that the HN 582 nt and the entire F gene sequences were as good for phylogenetic analysis as the entire HN gene sequence.
[Mh] Termos MeSH primário: Genoma Viral/genética
Proteína HN/genética
Vírus da Parainfluenza 3 Humana/genética
Infecções por Respirovirus/epidemiologia
Proteínas Virais de Fusão/genética
[Mh] Termos MeSH secundário: Sequência de Bases
Pré-Escolar
Croácia/epidemiologia
Seres Humanos
Lactente
Vírus da Parainfluenza 3 Humana/classificação
Vírus da Parainfluenza 3 Humana/isolamento & purificação
Filogenia
Infecções por Respirovirus/virologia
Análise de Sequência de RNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (HN Protein); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000459


  3 / 3427 MEDLINE  
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[PMID]:28468888
[Au] Autor:Leemans A; De Schryver M; Van der Gucht W; Heykers A; Pintelon I; Hotard AL; Moore ML; Melero JA; McLellan JS; Graham BS; Broadbent L; Power UF; Caljon G; Cos P; Maes L; Delputte P
[Ad] Endereço:Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium.
[Ti] Título:Antibody-Induced Internalization of the Human Respiratory Syncytial Virus Fusion Protein.
[So] Source:J Virol;91(14), 2017 Jul 15.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Respiratory syncytial virus (RSV) infections remain a major cause of respiratory disease and hospitalizations among infants. Infection recurs frequently and establishes a weak and short-lived immunity. To date, RSV immunoprophylaxis and vaccine research is mainly focused on the RSV fusion (F) protein, but a vaccine remains elusive. The RSV F protein is a highly conserved surface glycoprotein and is the main target of neutralizing antibodies induced by natural infection. Here, we analyzed an internalization process of antigen-antibody complexes after binding of RSV-specific antibodies to RSV antigens expressed on the surface of infected cells. The RSV F protein and attachment (G) protein were found to be internalized in both infected and transfected cells after the addition of either RSV-specific polyclonal antibodies (PAbs) or RSV glycoprotein-specific monoclonal antibodies (MAbs), as determined by indirect immunofluorescence staining and flow-cytometric analysis. Internalization experiments with different cell lines, well-differentiated primary bronchial epithelial cells (WD-PBECs), and RSV isolates suggest that antibody internalization can be considered a general feature of RSV. More specifically for RSV F, the mechanism of internalization was shown to be clathrin dependent. All RSV F-targeted MAbs tested, regardless of their epitopes, induced internalization of RSV F. No differences could be observed between the different MAbs, indicating that RSV F internalization was epitope independent. Since this process can be either antiviral, by affecting virus assembly and production, or beneficial for the virus, by limiting the efficacy of antibodies and effector mechanism, further research is required to determine the extent to which this occurs and how this might impact RSV replication. Current research into the development of new immunoprophylaxis and vaccines is mainly focused on the RSV F protein since, among others, RSV F-specific antibodies are able to protect infants from severe disease, if administered prophylactically. However, antibody responses established after natural RSV infections are poorly protective against reinfection, and high levels of antibodies do not always correlate with protection. Therefore, RSV might be capable of interfering, at least partially, with antibody-induced neutralization. In this study, a process through which surface-expressed RSV F proteins are internalized after interaction with RSV-specific antibodies is described. One the one hand, this antigen-antibody complex internalization could result in an antiviral effect, since it may interfere with virus particle formation and virus production. On the other hand, this mechanism may also reduce the efficacy of antibody-mediated effector mechanisms toward infected cells.
[Mh] Termos MeSH primário: Anticorpos Antivirais/metabolismo
Endocitose
Vírus Sincicial Respiratório Humano/imunologia
Proteínas Virais de Fusão/metabolismo
[Mh] Termos MeSH secundário: Complexo Antígeno-Anticorpo/metabolismo
Células Cultivadas
Citometria de Fluxo
Técnica Indireta de Fluorescência para Anticorpo
Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Viral); 0 (Antigen-Antibody Complex); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE


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[PMID]:28468881
[Au] Autor:Cifuentes-Muñoz N; Sun W; Ray G; Schmitt PT; Webb S; Gibson K; Dutch RE; Schmitt AP
[Ad] Endereço:Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky, USA.
[Ti] Título:Mutations in the Transmembrane Domain and Cytoplasmic Tail of Hendra Virus Fusion Protein Disrupt Virus-Like-Particle Assembly.
[So] Source:J Virol;91(14), 2017 Jul 15.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hendra virus (HeV) is a zoonotic paramyxovirus that causes deadly illness in horses and humans. An intriguing feature of HeV is the utilization of endosomal protease for activation of the viral fusion protein (F). Here we investigated how endosomal F trafficking affects HeV assembly. We found that the HeV matrix (M) and F proteins each induced particle release when they were expressed alone but that their coexpression led to coordinated assembly of virus-like particles (VLPs) that were morphologically and physically distinct from M-only or F-only VLPs. Mutations to the F protein transmembrane domain or cytoplasmic tail that disrupted endocytic trafficking led to failure of F to function with M for VLP assembly. Wild-type F functioned normally for VLP assembly even when its cleavage was prevented with a cathepsin inhibitor, indicating that it is endocytic F trafficking that is important for VLP assembly, not proteolytic F cleavage. Under specific conditions of reduced M expression, we found that M could no longer induce significant VLP release but retained the ability to be incorporated as a passenger into F-driven VLPs, provided that the F protein was competent for endocytic trafficking. The F and M proteins were both found to traffic through Rab11-positive recycling endosomes (REs), suggesting a model in which F and M trafficking pathways converge at REs, enabling these proteins to preassemble before arriving at plasma membrane budding sites. Hendra virus and Nipah virus are zoonotic paramyxoviruses that cause lethal infections in humans. Unlike that for most paramyxoviruses, activation of the henipavirus fusion protein occurs in recycling endosomal compartments. In this study, we demonstrate that the unique endocytic trafficking pathway of Hendra virus F protein is required for proper viral assembly and particle release. These results advance our basic understanding of the henipavirus assembly process and provide a novel model for the interplay between glycoprotein trafficking and paramyxovirus assembly.
[Mh] Termos MeSH primário: Vírus Hendra/genética
Multimerização Proteica
Proteínas Virais de Fusão/genética
Proteínas Virais de Fusão/metabolismo
Virossomos/metabolismo
[Mh] Termos MeSH secundário: Linhagem Celular
Endossomos/metabolismo
Seres Humanos
Proteínas Mutantes/genética
Proteínas Mutantes/metabolismo
Domínios Proteicos
Transporte Proteico
Proteínas da Matriz Viral/metabolismo
Virossomos/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Mutant Proteins); 0 (Viral Fusion Proteins); 0 (Viral Matrix Proteins); 0 (Virosomes)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE


  5 / 3427 MEDLINE  
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[PMID]:27773768
[Au] Autor:Kordyukova L
[Ad] Endereço:Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1-40, Moscow 119991, Russian Federation. Electronic address: kord@belozersky.msu.ru.
[Ti] Título:Structural and functional specificity of Influenza virus haemagglutinin and paramyxovirus fusion protein anchoring peptides.
[So] Source:Virus Res;227:183-199, 2017 01 02.
[Is] ISSN:1872-7492
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Two enveloped virus families, Orthomyxoviridae and Paramyxoviridae, comprise a large number of dangerous pathogens that enter the host cell via fusion of their envelope with a target cell membrane at acidic or neutral pH. The Class I prototypic glycoproteins responsible for this reaction are the Influenza virus haemagglutinin (HA) protein or paramyxovirus fusion (F) protein. X-ray crystallography and cryoelectron microscopy data are available for the HA and F ectodomains in pre- and post-fusion conformations, revealing similar spiky architectures, albeit with clear differences in the details. In contrast, their anchoring segments, which possess a linker region, transmembrane domain and cytoplasmic tail that is specifically modified with long fatty acids (highly conserved in HA and occasional in F), are not resolved. Recent experimental, bioinformatics and molecular modelling data showing the primary, secondary and quaternary organization of the HA and F anchoring segments are summarized in this review. Some amino acid patterns that are crucial for protein thermal stability or lipid membrane order/cholesterol binding are addressed, and new achievements in vaccine practice using HA transmembrane domain chimaeras are discussed. The oligomerization properties of the transmembrane domains are considered in the context of Group-1 and Group-2 antigenic HA subtypes and various genera/subfamilies of paramyxoviruses. A specific focus is the late steps of fusion that are reportedly facilitated by (1) ß-sheet-promoting ß-branched amino acids (valine and isoleucine) that are enriched in the transmembrane domain of paramyxovirus F or (2) a post-translational modification of C-terminal cysteines with palmitate/stearate (differential S-acylation) that is highly conserved in Influenza virus HA.
[Mh] Termos MeSH primário: Glicoproteínas de Hemaglutininação de Vírus da Influenza/química
Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo
Peptídeos/química
Domínios e Motivos de Interação entre Proteínas
Proteínas Virais de Fusão/química
Proteínas Virais de Fusão/metabolismo
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Sequência de Aminoácidos
Animais
Membrana Celular
Sequência Conservada
Seres Humanos
Lipídeos/química
Fusão de Membrana
Modelos Moleculares
Peptídeos/metabolismo
Conformação Proteica
Multimerização Proteica
Processamento de Proteína Pós-Traducional
Estabilidade Proteica
Relação Estrutura-Atividade
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Hemagglutinin Glycoproteins, Influenza Virus); 0 (Lipids); 0 (Peptides); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171218
[Lr] Data última revisão:
171218
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161107
[St] Status:MEDLINE


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[PMID]:28956592
[Au] Autor:Sousa IP; Carvalho CAM; Mendes YS; Weissmuller G; Oliveira AC; Gomes AMO
[Ad] Endereço:Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde and ‡Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro , Rio de Janeiro, Rio de Janeiro 21941-902, Brazil.
[Ti] Título:Fusion of a New World Alphavirus with Membrane Microdomains Involving Partially Reversible Conformational Changes in the Viral Spike Proteins.
[So] Source:Biochemistry;56(43):5823-5830, 2017 Oct 31.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Alphaviruses are enveloped arboviruses mainly proposed to infect host cells by receptor-mediated endocytosis followed by fusion between the viral envelope and the endosomal membrane. The fusion reaction is triggered by low pH and requires the presence of both cholesterol and sphingolipids in the target membrane, suggesting the involvement of lipid rafts in the cell entry mechanism. In this study, we show for the first time the interaction of an enveloped virus with membrane microdomains isolated from living cells. Using Mayaro virus (MAYV), a New World alphavirus, we verified that virus fusion to these domains occurred to a significant extent upon acidification, although its kinetics was quite slow when compared to that of fusion with artificial liposomes demonstrated in a previous work. Surprisingly, when virus was previously exposed to acidic pH, a condition previously shown to inhibit alphavirus binding and fusion to target membranes as well as infectivity, and then reneutralized, its ability to fuse with membrane microdomains at low pH was retained. Interestingly, this observation correlated with a partial reversion of low pH-induced conformational changes in viral proteins and retention of virus infectivity upon reneutralization. Our results suggest that MAYV entry into host cells could alternatively involve internalization via lipid rafts and that the conformational changes triggered by low pH in the viral spike proteins during the entry process are partially reversible.
[Mh] Termos MeSH primário: Alphavirus/química
Lipossomos/química
Fusão de Membrana
Microdomínios da Membrana/química
Proteínas Virais de Fusão/química
Internalização do Vírus
[Mh] Termos MeSH secundário: Alphavirus/metabolismo
Concentração de Íons de Hidrogênio
Microdomínios da Membrana/metabolismo
Proteínas Virais de Fusão/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Liposomes); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170929
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00650


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[PMID]:28863165
[Au] Autor:Wang Y; Yu W; Huo N; Wang W; Guo Y; Wei Q; Wang X; Zhang S; Yang Z; Xiao S
[Ad] Endereço:College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, P.R. China.
[Ti] Título:Comprehensive analysis of amino acid sequence diversity at the F protein cleavage site of Newcastle disease virus in fusogenic activity.
[So] Source:PLoS One;12(9):e0183923, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Newcastle disease virus (NDV) is a contagious agent of Newcastle disease in avian species and seriously affects the poultry industry. The cleavage site of the viral F protein (Fcs) is a key determinant of membrane fusion and viral virulence. In this study, we investigated the precise effect of variable amino acid sequences of the Fcs on fusogenic activity. Based on viral pathogenicity, the Fcs sequences of natural isolates (n = 1572) are classified into eight types of virulent Fcs (VFcs) with the motif "G/R/K-R-Q/R/K-R/K-R↓F" and ten types of the avirulent Fcs (AFcs) with the motif "G/R/E-R/K/Q-Q-G/E-R↓L". The VFcs is only found in the Class II cluster of viral classification and not in Class I. The AFcs exists in both Class I and II isolates. The VFc and AFc types present an evolutionary relationship with temporal distribution and host species. Using a fusion assay in vitro, VFcs-1 "RRQKR↓F" and VFcs-2 "RRQRR↓F" show the highest efficiency in triggering membrane fusion. The neutral residue Q at the P3 position of the VFcs plays an enhancing role compared to effect of the basic residues R and K. A single residue K at P3 or P5 is less efficient of the fusogenic activity in the VFcs with all basic residues. Moreover, the cleavage efficiencies of F0 proteins with different types of Fcs motifs do not appear to affect membrane fusion. Our findings offer insight into the effect of amino acid variation of the Fcs on the fusion triggered by NDV.
[Mh] Termos MeSH primário: Aminoácidos/química
Vírus da Doença de Newcastle/genética
Proteínas Virais de Fusão/química
[Mh] Termos MeSH secundário: Códon
Análise Mutacional de DNA
Evolução Molecular
Genoma Viral
Nucleotídeos/genética
Análise de Componente Principal
Recombinação Genética
Proteínas Virais de Fusão/genética
Virulência
Replicação Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Codon); 0 (Nucleotides); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170902
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183923


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[PMID]:28835504
[Au] Autor:Liu X; Liang B; Ngwuta J; Liu X; Surman S; Lingemann M; Kwong PD; Graham BS; Collins PL; Munir S
[Ad] Endereço:RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
[Ti] Título:Attenuated Human Parainfluenza Virus Type 1 Expressing the Respiratory Syncytial Virus (RSV) Fusion (F) Glycoprotein from an Added Gene: Effects of Prefusion Stabilization and Packaging of RSV F.
[So] Source:J Virol;91(22), 2017 Nov 15.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Human respiratory syncytial virus (RSV) is the most prevalent worldwide cause of severe respiratory tract infection in infants and young children. Human parainfluenza virus type 1 (HPIV1) also causes severe pediatric respiratory illness, especially croup. Both viruses lack vaccines. Here, we describe the preclinical development of a bivalent RSV/HPIV1 vaccine based on a recombinant HPIV1 vector, attenuated by a stabilized mutation, that expresses RSV F protein modified for increased stability in the prefusion (pre-F) conformation by previously described disulfide bond (DS) and hydrophobic cavity-filling (Cav1) mutations. RSV F was expressed from the first or second gene position as the full-length protein or as a chimeric protein with its transmembrane and cytoplasmic tail (TMCT) domains substituted with those of HPIV1 F in an effort to direct packaging in the vector particles. All constructs were recovered by reverse genetics. The TMCT versions of RSV F were packaged in the rHPIV1 particles much more efficiently than their full-length counterparts. In hamsters, the presence of the RSV F gene, and in particular the TMCT versions, was attenuating and resulted in reduced immunogenicity. However, the vector expressing full-length RSV F from the pre-N position was immunogenic for RSV and HPIV1. It conferred complement-independent high-quality RSV-neutralizing antibodies at titers similar to those of wild-type RSV and provided protection against RSV challenge. The vectors exhibited stable RSV F expression and In conclusion, an attenuated rHPIV1 vector expressing a pre-F-stabilized form of RSV F demonstrated promising immunogenicity and should be further developed as an intranasal pediatric vaccine. RSV and HPIV1 are major viral causes of acute pediatric respiratory illness for which no vaccines or suitable antiviral drugs are available. The RSV F glycoprotein is the major RSV neutralization antigen. We used a rHPIV1 vector, bearing a stabilized attenuating mutation, to express the RSV F glycoprotein bearing amino acid substitutions that increase its stability in the pre-F form, the most immunogenic form that elicits highly functional virus-neutralizing antibodies. RSV F was expressed from the pre-N or N-P gene position of the rHPIV1 vector as a full-length protein or as a chimeric form with its TMCT domain derived from HPIV1 F. TMCT modification greatly increased packaging of RSV F into the vector particles but also increased vector attenuation , resulting in reduced immunogenicity. In contrast, full-length RSV F expressed from the pre-N position was immunogenic, eliciting complement-independent RSV-neutralizing antibodies and providing protection against RSV challenge.
[Mh] Termos MeSH primário: Expressão Gênica
Vetores Genéticos
Vírus da Parainfluenza 1 Humana/fisiologia
Infecções por Vírus Respiratório Sincicial
Vacinas contra Vírus Sincicial Respiratório
Vírus Sinciciais Respiratórios
Proteínas Virais de Fusão
Montagem de Vírus
[Mh] Termos MeSH secundário: Animais
Anticorpos Neutralizantes/imunologia
Anticorpos Antivirais/imunologia
Cercopithecus aethiops
Cobaias
Seres Humanos
Mesocricetus
Proteínas Recombinantes/genética
Proteínas Recombinantes/imunologia
Infecções por Vírus Respiratório Sincicial/genética
Infecções por Vírus Respiratório Sincicial/imunologia
Infecções por Vírus Respiratório Sincicial/prevenção & controle
Vacinas contra Vírus Sincicial Respiratório/genética
Vacinas contra Vírus Sincicial Respiratório/imunologia
Vírus Sinciciais Respiratórios/genética
Vírus Sinciciais Respiratórios/imunologia
Células Vero
Proteínas Virais de Fusão/genética
Proteínas Virais de Fusão/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Neutralizing); 0 (Antibodies, Viral); 0 (Recombinant Proteins); 0 (Respiratory Syncytial Virus Vaccines); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170825
[St] Status:MEDLINE


  9 / 3427 MEDLINE  
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[PMID]:28794038
[Au] Autor:van Erp EA; van Kasteren PB; Guichelaar T; Ahout IML; de Haan CAM; Luytjes W; Ferwerda G; Wicht O
[Ad] Endereço:Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands liz.van.erp@rivm.nl.
[Ti] Título: Enhancement of Respiratory Syncytial Virus Infection by Maternal Antibodies Does Not Explain Disease Severity in Infants.
[So] Source:J Virol;91(21), 2017 Nov 01.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Respiratory syncytial virus (RSV) is the leading cause of severe respiratory illness in infants. At this young age, infants typically depend on maternally transferred antibodies (matAbs) and their innate immune system for protection against infections. RSV-specific matAbs are thought to protect from severe illness, yet severe RSV disease occurs mainly below 6 months of age, when neutralizing matAb levels are present. To investigate this discrepancy, we asked if disease severity is related to antibody properties other than neutralization. Some antibody effector functions are mediated via their Fc binding region. However, it has been shown that this binding may lead to antibody-dependent enhancement (ADE) of infection or reduction of neutralization, both possibly leading to more disease. In this study, we first showed that high levels of ADE of RSV infection occur in monocytic THP-1 cells in the presence of RSV antibodies and that neutralization by these antibodies was reduced in Vero cells when they were transduced with Fc gamma receptors. We then demonstrated that antibodies from cotton rats with formalin-inactivated (FI)-RSV-induced pulmonary pathology were capable of causing ADE. Human matAbs also caused ADE and were less neutralizing in cells that carry Fc receptors. However, these effects were unrelated to disease severity because they were seen both in uninfected controls and in infants hospitalized with different levels of RSV disease severity. We conclude that ADE and reduction of neutralization are unlikely to be involved in RSV disease in infants with neutralizing matAbs. It is unclear why severity of RSV disease peaks at the age when infants have neutralizing levels of maternal antibodies. Additionally, the exact reason for FI-RSV-induced enhanced disease, as seen in the 1960s vaccine trials, is still unclear. We hypothesized that antibodies present under either of these conditions could contribute to disease severity. Antibodies can have effects that may lead to more disease instead of protection. We investigated two of those effects: antibody-dependent enhancement of infection (ADE) and neutralization reduction. We show that ADE occurs with antibodies from FI-RSV-immunized RSV-infected cotton rats. Moreover, passively acquired maternal antibodies from infants had the capacity to induce ADE and reduction of neutralization. However, no clear association with disease severity was seen, ruling out that these properties explain disease in the presence of maternal antibodies. Our data contribute to a better understanding of the impact of antibodies on RSV disease in infants.
[Mh] Termos MeSH primário: Anticorpos Neutralizantes/imunologia
Anticorpos Antivirais/imunologia
Receptores de IgG/metabolismo
Infecções por Vírus Respiratório Sincicial/imunologia
Vacinas contra Vírus Sincicial Respiratório/administração & dosagem
Vírus Sinciciais Respiratórios/imunologia
Índice de Gravidade de Doença
[Mh] Termos MeSH secundário: Animais
Anticorpos Antivirais/sangue
Anticorpos Facilitadores
Estudos de Casos e Controles
Cercopithecus aethiops
Feminino
Seres Humanos
Lactente
Pulmão/imunologia
Pulmão/patologia
Pulmão/virologia
Monócitos/imunologia
Monócitos/patologia
Monócitos/virologia
Testes de Neutralização
Ratos
Receptores de IgG/imunologia
Infecções por Vírus Respiratório Sincicial/prevenção & controle
Sigmodontinae
Vacinação
Células Vero
Proteínas do Envelope Viral/imunologia
Proteínas Virais de Fusão/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Neutralizing); 0 (Antibodies, Viral); 0 (Receptors, IgG); 0 (Respiratory Syncytial Virus Vaccines); 0 (Viral Envelope Proteins); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE


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[PMID]:28646649
[Au] Autor:Ji Y; Liu T; Jia Y; Liu B; Yu Q; Cui X; Guo F; Chang H; Zhu Q
[Ad] Endereço:State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, PR China.
[Ti] Título:Two single mutations in the fusion protein of Newcastle disease virus confer hemagglutinin-neuraminidase independent fusion promotion and attenuate the pathogenicity in chickens.
[So] Source:Virology;509:146-151, 2017 Sep.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The fusion (F) protein of Newcastle disease virus (NDV) affects viral infection and pathogenicity through mediating membrane fusion. Previously, we found NDV with increased fusogenic activity in which contained T458D or G459D mutation in the F protein. Here, we investigated the effects of these two mutations on viral infection, fusogenicity and pathogenicity. Syncytium formation assays indicated that T458D or G459D increased the F protein cleavage activity and enhanced cell fusion with or without the presence of HN protein. The T458D- or G459D-mutated NDV resulted in a decrease in virus replication or release from cells. The animal study showed that the pathogenicity of the mutated NDVs was attenuated in chickens. These results indicate that these two single mutations in F altered or diminished the requirement of HN for promoting membrane fusion. The increased fusogenic activity may disrupt the cellular machinery and consequently decrease the virus replication and pathogenicity in chickens.
[Mh] Termos MeSH primário: Proteínas Mutantes/metabolismo
Mutação de Sentido Incorreto
Doença de Newcastle/patologia
Vírus da Doença de Newcastle/fisiologia
Proteínas Virais de Fusão/metabolismo
Internalização do Vírus
[Mh] Termos MeSH secundário: Animais
Fusão Celular
Galinhas
Modelos Animais de Doenças
Células Gigantes/virologia
Proteínas Mutantes/genética
Doença de Newcastle/virologia
Vírus da Doença de Newcastle/genética
Vírus da Doença de Newcastle/patogenicidade
Proteínas Virais de Fusão/genética
Virulência
Replicação Viral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Mutant Proteins); 0 (Viral Fusion Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170721
[Lr] Data última revisão:
170721
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170625
[St] Status:MEDLINE



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