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1.
J Exp Med ; 190(3): 435-44, 1999 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10430631

RESUMO

Until now, it has been unclear whether murine cytomegalovirus (MCMV)-encoded protein m144 directly regulates natural killer (NK) cell effector function and whether the effects of m144 are only strictly evident in the context of MCMV infection. We have generated clones of the transporter associated with antigen processing (TAP)-2-deficient RMA-S T lymphoma cell line and its parent cell line, RMA, that stably express significant and equivalent levels of m144. In vivo NK cell-mediated rejection of RMA-S-m144 lymphomas was reduced compared with rejection of parental or mock-transfected RMA-S clones, indicating the ability of m144 to regulate NK cell-mediated responses in vivo. Significantly, the accumulation of NK cells in the peritoneum was reduced in mice challenged with RMA-S-m144, as was the lytic activity of NK cells recovered from the peritoneum. Expression of m144 on RMA-S cells also conferred resistance to cytotoxicity mediated in vitro by interleukin 2-activated adherent spleen NK cells. In summary, the data demonstrate that m144 confers some protection from NK cell effector function mediated in the absence of target cell class I expression, but that in vivo the major effect of m144 is to regulate NK cell accumulation and activation at the site of immune challenge.


Assuntos
Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I , Células Matadoras Naturais/imunologia , Linfoma de Células T/imunologia , Muromegalovirus/imunologia , Proteínas Virais/fisiologia , Animais , Movimento Celular/imunologia , Citotoxicidade Imunológica/genética , Rejeição de Enxerto/genética , Antígenos de Histocompatibilidade Classe I/genética , Imunidade Inata , Células Matadoras Naturais/virologia , Ativação Linfocitária , Linfoma de Células T/genética , Linfoma de Células T/metabolismo , Linfoma de Células T/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Homologia de Sequência de Aminoácidos , Transfecção , Células Tumorais Cultivadas , Proteínas Virais/biossíntese , Proteínas Virais/imunologia
2.
J Vet Intern Med ; 23(3): 450-61, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19645832

RESUMO

Equine herpesvirus-1 is a highly prevalent and frequently pathogenic infection of equids. The most serious clinical consequences of infection are abortion and equine herpesvirus myeloencephalopathy (EHM). In recent years, there has been an apparent increase in the incidence of EHM in North America, with serious consequences for horses and the horse industry. This consensus statement draws together current knowledge in the areas of pathogenesis, strain variation, epidemiology, diagnostic testing, vaccination, outbreak prevention and control, and treatment.


Assuntos
Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/fisiologia , Doenças dos Cavalos/virologia , Animais , Doenças do Sistema Nervoso Central/veterinária , Doenças do Sistema Nervoso Central/virologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Feminino , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/prevenção & controle , Herpesvirus Equídeo 1/classificação , Doenças dos Cavalos/epidemiologia , Cavalos , Gravidez , Complicações Infecciosas na Gravidez/veterinária , Complicações Infecciosas na Gravidez/virologia , Fatores de Risco , Vacinas Virais/imunologia
3.
Vet Microbiol ; 113(3-4): 243-9, 2006 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-16338104

RESUMO

Equine herpesvirus-1 (EHV-1) is responsible for respiratory disease and abortion in pregnant mares. Some high virulence isolates of EHV-1 also cause neurological disease. The pathogenesis of both abortion and neurological disease relates in part, to thrombus formation occurring in the pregnant uterus and central nervous system. The differences in disease outcome may relate to differing abilities of high and low virulence EHV-1 isolates to cause cell-associated viraemia, infect endothelial cells and cause thrombosis at sites distant from the respiratory tract. This study attempted to identify in vitro assays, which could be used to characterise the interaction between these isolates, equine endothelial cells and clotting factors. No significant difference was found between the growth kinetics of high and low virulence isolates of EHV-1 in polarised endothelial cells. For both isolates, virus was released preferentially from the apical surface of the polarised cells. The functional effects of viral infection on endothelial cells, with reference to virally-induced thrombosis were then investigated. Endothelial cells were grown on microcarrier beads, infected with EHV-1 and assayed for procoagulant activity. No significant difference in clotting time was observed between mock and EHV-1 infected endothelial cells in microcarrier cultures. Thus the degree of thrombosis may reflect a more complex interaction between endothelial cells, circulating leucocytes and other factors in the microenvironment.


Assuntos
Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/crescimento & desenvolvimento , Herpesvirus Equídeo 1/patogenicidade , Doenças dos Cavalos/virologia , Trombose/veterinária , Animais , Células Cultivadas , Células Endoteliais/virologia , Infecções por Herpesviridae/virologia , Cavalos , Microesferas , Trombose/virologia , Viremia/veterinária , Virulência
4.
Vet Immunol Immunopathol ; 111(1-2): 3-13, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16542736

RESUMO

Amongst the infectious diseases that threaten equine health, herpesviral infections remain a world wide cause of serious morbidity and mortality. Equine herpesvirus-1 infection is the most important pathogen, causing an array of disorders including epidemic respiratory disease abortion, neonatal foal death, myeloencephalopathy and chorioretinopathy. Despite intense scientific investigation, extensive use of vaccination, and established codes of practice for control of disease outbreaks, infection and disease remain common. While equine herpesvirus-1 infection remains a daunting challenge for immunoprophylaxis, many critical advances in equine immunology have resulted in studies of this virus, particularly related to MHC-restricted cytotoxicity in the horse. A workshop was convened in San Gimignano, Tuscany, Italy in June 2004, to bring together clinical and basic researchers in the field of equine herpesvirus-1 study to discuss the latest advances and future prospects for improving our understanding of these diseases, and equine immunity to herpesviral infection. This report highlights the new information that was the focus of this workshop, and is intended to summarize this material and identify the critical questions in the field.


Assuntos
Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1 , Doenças dos Cavalos/virologia , Animais , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/prevenção & controle , Infecções por Herpesviridae/virologia , Doenças dos Cavalos/imunologia , Doenças dos Cavalos/prevenção & controle , Cavalos
5.
Curr Top Microbiol Immunol ; 269: 131-51, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12224506

RESUMO

Homologues of MHC class I proteins have been identified in the genomes of human, murine and rat cytomegaloviruses (CMVs). Given the pivotal role of the MHC class I protein in cellular immunity, it has been postulated that the viral homologues subvert the normal antiviral immune response of the host, thus promoting virus replication and dissemination in an otherwise hostile environment. This review focuses on recent studies of the CMV MHC class I homologues at the molecular, cellular and whole animal level and presents current hypotheses for their roles in the CMV life cycle.


Assuntos
Proteínas de Caenorhabditis elegans , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Proteínas Nucleares , Fatores de Transcrição , Animais , Proteínas de Transporte/metabolismo , Regulação para Baixo , Humanos , Imunidade Celular , Células Matadoras Naturais/imunologia , Receptores Virais/metabolismo , Linfócitos T Citotóxicos/imunologia , Replicação Viral
6.
Microbes Infect ; 2(5): 521-32, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10865197

RESUMO

Viruses that establish a persistent infection with their host have evolved numerous strategies to evade the immune system. Consequently, they are useful tools to dissect the complex cellular processes that comprise the immune response. Rapid progress has been made in recent years in defining the role of cellular MHC class I molecules in regulating the response of natural killer (NK) cells. Concomitantly, the roles of the MHC class I homologues encoded by human and mouse cytomegaloviruses in evading or subverting NK cell responses has received considerable interest. This review discusses the results from a number of studies that have pursued the biological function of the viral MHC class I homologues. Based on the evidence from these studies, hypotheses for the possible role of these intriguing molecules are presented.


Assuntos
Proteínas do Capsídeo , Citomegalovirus , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Animais , Capsídeo/imunologia , Capsídeo/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Humanos , Camundongos , Transdução de Sinais , Proteínas Virais/imunologia
7.
J Virol Methods ; 88(1): 89-104, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10921846

RESUMO

Three filamentous phage random peptide display libraries were used in biopanning experiments with purified IgG from the serum of a gnotobiotic foal infected with equine herpesvirus-1 (EHV-1) to enrich for epitopes binding to anti-EHV-1 antibodies. The sequences of the amino acids displayed were aligned with protein sequences of EHV-1, thereby identifying a number of potential antibody binding regions. Presumptive epitopes were identified within the proteins encoded by genes 7 (DNA helicase/primase complex protein), 11 (tegument protein), 16 (glycoprotein C), 41 (integral membrane protein), 70 (glycoprotein G), 71 (envelope glycoprotein gp300), and 74 (glycoprotein E). Two groups of sequences, which aligned with either glycoprotein C (gC) or glycoprotein E (gE), identified type-specific epitopes which could be used to distinguish between sera from horses infected with either EHV-1 or EHV-4 in an ELISA using either the phage displaying the peptide or synthetic peptides as antigen. The gC epitope had been previously identified as an immunogenic region by conventional monoclonal antibody screening whereas the gE antibody binding region had not been previously identified. This demonstrates that screening of phage display peptide libraries with post-infection polyclonal sera is a suitable method for identifying diagnostic antigens for viral infections such as EHV-1.


Assuntos
Anticorpos Antivirais/imunologia , Herpesvirus Equídeo 1/imunologia , Biblioteca de Peptídeos , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Bacteriófagos/genética , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/imunologia , Doenças dos Cavalos/virologia , Cavalos , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA
8.
J Virol Methods ; 90(2): 167-83, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11064117

RESUMO

Enzyme-linked immunosorbant assays (ELISAs) were developed for the detection of antibodies against the major envelope glycoprotein (G(L)) of equine arteritis virus (EAV). A 6-Histidine tagged recombinant protein expressing the complete G(L) ectodomain (G(L)-6His), a glutathione-S-transferase recombinant protein expressing amino acids 55-98 of G(L) (G(L)-GST) and an ovalbumin-conjugated synthetic peptide representing amino acids 81-106 of G(L) (G(L)-OVA) were used as diagnostic antigens. An ELISA procedure was developed and optimised for each antigen. The G(L)-OVA and G(L)-6His assays showed the greatest specificity while the G(L)-GST assay was slightly more sensitive that the G(L)-OVA and G(L)-6His assays; results based on the analysis of 50 virus neutralisation positive and 50 virus neutralisation negative sera. The G(L)-OVA ELISA was selected for further evaluation since it was simpler to use than ELISAs based on recombinant antigens and did not suffer from background reactivity. The final sensitivity and specificity of the G(L)-OVA ELISA were 96.75 and 95.6%, respectively, results based on the analysis of 400 virus neutralisation positive and 400 virus neutralisation negative sera. It also detected EAV antibody (100% efficiency) in seropositive shedding stallions and, in ponies infected experimentally with the UK93 isolate of EAV, the appearance of virus neutralising antibodies and G(L)-OVA ELISA-specific immunoglobulins coincided.


Assuntos
Anticorpos Antivirais/análise , Infecções por Arterivirus/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Equartevirus/imunologia , Doenças dos Cavalos/diagnóstico , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Glutationa Transferase/imunologia , Glutationa Transferase/metabolismo , Histidina/imunologia , Doenças dos Cavalos/imunologia , Cavalos , Ovalbumina/imunologia , Proteínas Recombinantes de Fusão/imunologia , Sensibilidade e Especificidade , Reino Unido
9.
Res Vet Sci ; 75(1): 83-6, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12801466

RESUMO

Basic in vitro characteristics of high and low virulence isolates of equine herpesviruses-1 and -4 were investigated with particular reference made to the Ab4 and V592 isolates of EHV-1 as both have distinct endotheliotropism and clinical outcomes in pony challenge studies. Additionally, some EHV-4 isolates that showed variations in clinical outcome were included in some experiments. The aim of the study was to identify an in vitro characteristic that would differentiate strains of known virulence. Such a system could then be applied to vaccine and virulence studies as an effective screening tool. Viral growth kinetics in a variety of cell culture systems, plaque size, ability to replicate in fetal endothelium in organ culture, and sensitivity to acyclovir were compared. No reliable marker system that differentiated between higher and lower virulence isolates of EHV-1 and EHV-4 was identified.


Assuntos
Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/patogenicidade , Herpesvirus Equídeo 4/patogenicidade , Doenças dos Cavalos/virologia , Animais , Endotélio/patologia , Endotélio/virologia , Infecções por Herpesviridae/patologia , Infecções por Herpesviridae/virologia , Herpesvirus Equídeo 1/crescimento & desenvolvimento , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 4/crescimento & desenvolvimento , Herpesvirus Equídeo 4/isolamento & purificação , Cavalos , Técnicas In Vitro , Ensaio de Placa Viral , Virulência
10.
Equine Vet J ; 35(5): 458-62, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12875323

RESUMO

REASONS FOR PERFORMING STUDY: Vaccination and challenge studies in ponies are the most relevant experimental system for predicting whether strains included in equine influenza vaccines are relevant, but they are difficult to perform. OBJECTIVES: In order to investigate the feasibility of using a small animal model, results of a cross-protection study in hamsters were compared with those from a previous pony challenge experiment. METHODS: Animals were immunised with inactivated vaccines containing one of 4 strains of equine influenza A H3N8 subtype virus isolated over a 26 year period (1963 to 1989), then challenged with a 1989 strain. RESULTS: Although there was no significant difference in titres of excreted virus between groups of vaccinated ponies, hamsters immunised with heterologous strains had significantly higher virus titres in the lung than hamsters vaccinated with the homologous strain. In both ponies and hamsters, the number of animals excreting virus was greater the earlier the isolation date of the vaccine strain, although this was only significant in the hamster study. CONCLUSIONS: Despite differences, the overall conclusion of both the pony and hamster models was that heterologous vaccines may be less effective than homologous vaccines at preventing virus excretion. POTENTIAL RELEVANCE: Further validation is required, but the hamster model shows potential for preliminary assessment of the effects of antigenic drift on vaccine efficacy.


Assuntos
Variação Antigênica , Doenças dos Cavalos/prevenção & controle , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/veterinária , Animais , Anticorpos Antivirais/sangue , Cricetinae , Reações Cruzadas , Cavalos , Pulmão/virologia , Mesocricetus , Modelos Animais , Infecções por Orthomyxoviridae/prevenção & controle , Distribuição Aleatória , Vacinas Atenuadas/imunologia , Eliminação de Partículas Virais
12.
Neuroscience ; 207: 148-66, 2012 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-22306285

RESUMO

Sensory input from the airways to suprapontine brain regions contributes to respiratory sensations and the regulation of respiratory function. However, relatively little is known about the central organization of this higher brain circuitry. We exploited the properties of the H129 strain of herpes simplex virus 1 (HSV-1) to perform anterograde transneuronal tracing of the central projections of airway afferent nerve pathways. The extrathoracic trachea in Sprague-Dawley rats was inoculated with HSV-1 H129, and tissues along the neuraxis were processed for HSV-1 immunoreactivity. H129 infection appeared in the vagal sensory ganglia within 24 h and the number of infected cells peaked at 72 h. Brainstem nuclei, including the nucleus of the solitary tract and trigeminal sensory nuclei were infected within 48 h, and within 96 h infected cells were evident within the pons (lateral and medial parabrachial nuclei), thalamus (ventral posteromedial, ventral posterolateral, submedius, and reticular nuclei), hypothalamus (paraventricular and lateral nuclei), subthalamus (zona incerta), and amygdala (central and anterior amygdala area). At later times H129 was detected in cortical forebrain regions including the insular, orbital, cingulate, and somatosensory cortices. Vagotomy significantly reduced the number of infected cells within vagal sensory nuclei in the brainstem, confirming the main pathway of viral transport is through the vagus nerves. Sympathetic postganglionic neurons in the stellate and superior cervical ganglia were infected by 72 h, however, there was no evidence for retrograde transynaptic movement of the virus in sympathetic pathways in the central nervous system (CNS). These data demonstrate the organization of key structures within the CNS that receive afferent projections from the extrathoracic airways that likely play a role in the perception of airway sensations.


Assuntos
Herpesvirus Humano 1/fisiologia , Técnicas de Rastreamento Neuroanatômico/métodos , Marcadores do Trato Nervoso/metabolismo , Traqueia/inervação , Fibras Aferentes Viscerais/citologia , Animais , Transporte Axonal/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Células Receptoras Sensoriais/citologia , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/virologia , Traqueia/fisiologia , Traqueia/virologia , Fibras Aferentes Viscerais/metabolismo , Fibras Aferentes Viscerais/virologia
14.
J Gen Virol ; 90(Pt 1): 59-68, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19088273

RESUMO

Murine cytomegalovirus (MCMV) M78 is a member of the betaherpesvirus 'UL78 family' of seven transmembrane receptor (7TMR) genes. Previous studies of M78 and its counterpart in rat cytomegalovirus (RCMV) have suggested that these genes are required for efficient cell-cell spread of their respective viruses in tissue culture and demonstrated that gene knockout viruses are significantly attenuated for replication in vivo. However, in comparison with other CMV 7TMRs, relatively little is known about the basic biochemical properties and subcellular trafficking of the UL78 family members. We have characterized MCMV M78 in both transiently transfected and MCMV-infected cells to determine whether M78 exhibits features in common with cellular 7TMR. We obtained preliminary evidence that M78 formed dimers, a property that has been reported for several cellular 7TMR. M78 traffics to the cell surface, but was rapidly and constitutively endocytosed. Antibody feeding experiments demonstrated co-localization of M78 with markers for both the clathrin-dependent and lipid raft/caveolae-mediated internalization pathways. In MCMV-infected cells, the subcellular localization of M78 was modified during the course of infection, which may be related to the incorporation of M78 into the virion envelope during the course of virion maturation.


Assuntos
Proteínas de Membrana/metabolismo , Muromegalovirus/fisiologia , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Cricetinae , Dimerização , Endocitose , Humanos , Camundongos , Transporte Proteico
15.
J Virol ; 80(8): 4047-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16571821

RESUMO

Equid herpesvirus 1 (EHV-1) can cause a wide spectrum of diseases ranging from inapparent respiratory infection to the induction of abortion and, in extreme cases, neurological disease resulting in paralysis and ultimately death. It has been suggested that distinct strains of EHV-1 that differ in pathogenic capacity circulate in the field. In order to investigate this hypothesis, it was necessary to identify genetic markers that allow subgroups of related strains to be identified. We have determined all of the genetic differences between a neuropathogenic strain (Ab4) and a nonneuropathogenic strain (V592) of EHV-1 and developed PCR/sequencing procedures enabling differentiation of EHV-1 strains circulating in the field. The results indicate the occurrence of several major genetic subgroups of EHV-1 among isolates recovered from outbreaks over the course of 30 years, consistent with the proposal that distinct strains of EHV-1 circulate in the field. Moreover, there is evidence that certain strain groups are geographically restricted, being recovered predominantly from outbreaks occurring in either North America or Europe. Significantly, variation of a single amino acid of the DNA polymerase is strongly associated with neurological versus nonneurological disease outbreaks. Strikingly, this variant amino acid occurs at a highly conserved position for herpesvirus DNA polymerases, suggesting an important functional role.


Assuntos
DNA Polimerase Dirigida por DNA/genética , Herpesvirus Equídeo 1/patogenicidade , Mutação Puntual , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Polimerase Dirigida por DNA/química , Surtos de Doenças , Herpesvirus Equídeo 1/classificação , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/epidemiologia , Cavalos , Dados de Sequência Molecular , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único
16.
J Gen Virol ; 87(Pt 9): 2507-2515, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16894188

RESUMO

Equine herpesvirus 1 (EHV-1) causes respiratory and neurological disease and abortion in horses. Animals with high frequencies of cytotoxic T lymphocytes (CTL) show reduced severity of respiratory disease and frequency of abortion, probably by CTL-mediated control of cell-associated viraemia. This study aimed to identify CTL epitopes restricted by selected major histocompatibility complex (MHC) class I alleles expressed in the equine leukocyte antigen (ELA) A3 haplotype. Effector CTL were induced from EHV-1-primed ponies and thoroughbreds with characterized MHC class I haplotypes and screened against P815 target cells transfected with selected EHV-1 genes and MHC class I genes. Targets that expressed EHV-1 gene 64 and the MHC B2 gene were lysed by effector CTL in a genetically restricted manner. There was no T-cell recognition of targets expressing either the MHC B2 gene and EHV-1 genes 2, 12, 14, 16, 35, 63 or 69, or the MHC C1 gene and EHV-1 genes 12, 14, 16 or 64. A vaccinia virus vector encoding gene 64 (NYVAC-64) was also investigated. Using lymphocytes from ELA-A3 horses, the recombinant NYVAC-64 virus induced effector CTL that lysed EHV-1-infected target cells; the recombinant virus also supplied a functional peptide that was expressed by target cells and recognized in an MHC-restricted fashion by CTL induced with EHV-1. This construct may therefore be used to determine the antigenicity of EHV-1 gene 64 for other MHC haplotypes. These techniques are broadly applicable to the identification of additional CTL target proteins and their presenting MHC alleles, not only for EHV-1, but for other equine viruses.


Assuntos
Antígenos Virais , Epitopos , Herpesvirus Equídeo 1/imunologia , Linfócitos T Citotóxicos/imunologia , Alelos , Animais , Antígenos Virais/genética , Sequência de Bases , Clonagem Molecular , DNA Viral/genética , Epitopos/genética , Genes MHC Classe I , Genes Virais , Vetores Genéticos , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/genética , Doenças dos Cavalos/imunologia , Doenças dos Cavalos/virologia , Cavalos , Técnicas In Vitro , Transfecção , Vaccinia virus/genética , Vaccinia virus/imunologia
17.
Vaccine ; 24(10): 1490-500, 2006 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-16269205

RESUMO

Equine herpesvirus-1 (EHV-1) is a ubiquitous pathogen of horses, which continues to cause respiratory and neurological disease and abortion, despite the widespread use of vaccines. Cell mediated immunity (CMI) is thought to play a major role in protection against infection with EHV-1. The aim of this study was to characterise the virus-specific CMI response in ponies vaccinated with vP1014, a vaccinia-based construct (NYVAC) coding for the immediate early gene (gene 64) of EHV-1. This gene product is a CTL target protein for an equine MHC class I allele expressed on the A3 haplotype. EHV-primed yearling ponies expressing this haplotype were vaccinated once (n = 1), three (n = 1), or four times (n = 2), and one pony was kept as an unvaccinated control. Cytotoxic T lymphocyte (CTL) activity and interferon gamma (IFN-gamma) synthesis were measured before and after vaccination and challenge infection with EHV-1. Multiple immunisations with vP1014 resulted in increased CTL activity and IFN-gamma synthesis specific for EHV-1 compared with unvaccinated or singly vaccinated ponies. The phenotype of EHV-1 specific T-cells synthesising IFN-gamma was also modified by immunisation. In the unvaccinated pony, the predominant population synthesising IFN-gamma after EHV-1 stimulation was CD8alpha+. In contrast, multiply vaccinated ponies demonstrated an increased proportion of CD8alpha- T-cells synthesising IFN-gamma. The results demonstrated that vaccination with a NYVAC-based construct coding for gene 64 stimulated CMI. This immune response alone did not protect against challenge infection. However, the study does illustrate that vaccinia-based vaccines can stimulate CMI in the horse and may therefore contribute to protection against disease caused by EHV-1.


Assuntos
Genes Precoces , Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/imunologia , Vacinas contra Herpesvirus/imunologia , Doenças dos Cavalos/prevenção & controle , Interferon gama/biossíntese , Linfócitos T Citotóxicos/imunologia , Vacinas de DNA/imunologia , Animais , Anticorpos Antivirais/biossíntese , Feminino , Infecções por Herpesviridae/prevenção & controle , Cavalos , Imunofenotipagem , Masculino , Vacinação
18.
J Virol ; 68(11): 6985-93, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7933080

RESUMO

We have developed a complementation assay, using transiently transfected COS cells, to facilitate a molecular analysis of the herpes simplex virus type 1 glycoprotein gH. When infected by a gH-null syncytial virus, COS cells expressing wild-type gH generate infectious progeny virions and form a syncytium with neighboring cells. By deletion and point mutagenesis, we have found particular residues in the gH cytoplasmic tail to be essential for generation of a syncytium but apparently dispensable for production of infectious virions. This study emphasizes the different requirements for cell-cell and cell-envelope fusion and demonstrates that changes in the non-syn locus UL22-gH can reverse the syncytial phenotype.


Assuntos
Herpesvirus Humano 1/fisiologia , Proteínas do Envelope Viral/fisiologia , Alanina , Sequência de Aminoácidos , Animais , Sequência de Bases , Chlorocebus aethiops , Teste de Complementação Genética , Dados de Sequência Molecular , Mutação , Relação Estrutura-Atividade , Células Vero , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
19.
J Virol ; 68(11): 7586-90, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7933147

RESUMO

The contributions of a set of herpes simplex virus type 1 membrane proteins towards the process of cell-cell fusion were examined with a series of deletion mutants into which a syncytial mutation had been introduced at codon 855 of the glycoprotein B (gB) gene. Analysis of the fusion phenotypes of these recombinant viruses in Vero cells revealed that while gC, gG, US5, and UL43 are dispensable for syncytium formation at both high and low multiplicities of infection, gD, gHgL, gE, gI, and gM were all required for the fusion of cellular membranes. These data confirm that the requirements for virion entry and cell-cell fusion are not identical. gD and gHgL, like gB, are essential for both processes. gG, gI, and gM, on the other hand, are dispensable for virus penetration, yet play a role in cell-to-cell spread by the direct contact route, at least on an SC16 gBANG background.


Assuntos
Herpesvirus Humano 1/fisiologia , Proteínas do Envelope Viral/fisiologia , Animais , Membrana Celular/virologia , Chlorocebus aethiops , Mutação , Células Vero , Proteínas do Envelope Viral/genética , Vírion/fisiologia
20.
Immunol Cell Biol ; 74(6): 513-22, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8989589

RESUMO

Herpesviruses have acquired a variety of different mechanisms to avoid the damaging effects of host immunity. Frequently, these viruses subvert normal immune regulatory functions utilized by the host. The focus of this review is upon herpesvirus genes encoding known or potential immunomodulatory proteins. Areas covered include inhibition of complement and antibody function, herpesvirus-encoded homologues of cytokines and chemokine receptors, and potential disruption of cellular recognition of virally infected targets.


Assuntos
Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Herpesviridae/imunologia , Herpesviridae/patogenicidade , Sequência de Aminoácidos , Animais , Infecções por Herpesviridae/etiologia , Humanos , Dados de Sequência Molecular
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