| expression of ha of hpai h5n1 virus at us2 gene insertion site of turkey herpesvirus induced better protection than that at us10 gene insertion site. | herpesvirus of turkey (hvt) is being widely used as a vector for development of recombinant vaccines and us2 and us10 genes are often chosen as insertion sites for targeted gene expression. however, the different effects of the two genes for generation of recombinant hvt vaccines were unknown. in order to compare the effects of inserted genes in the two sites on the efficacy of the recombinant vaccines, host-protective haemagglutinin (ha) gene of the highly pathogenic avian influenza virus (hpai ... | 2011 | 21818336 |
| development and application of a phosphoproteomic method using electrostatic repulsion-hydrophilic interaction chromatography (erlic), imac, and lc-ms/ms analysis to study marek's disease virus infection. | marek's disease (md) is an avian neoplastic disease caused by marek's disease virus (mdv). the mechanism of virus transition between the lytic and latent cycle is still being investigated; however, post-translational modifications, especially phosphorylation, have been thought to play an important role. previously, our group has used strong cation exchange chromatography in conjunction with reversed-phase liquid chromatography-tandem mass spectrometry (lc-ms/ms) to study the changes in global pr ... | 2011 | 21736374 |
| heat-shock protein 70 is associated with the entry of marek's disease virus into fibroblast. | literature pertaining to the interactions between marek's disease virus (mdv) entry-related glycoproteins and corresponding receptors is still limited. results from a western blot analysis of cellular proteins for virus receptors and co-immunoprecipitation suggest that heat shock protein 70 (hsp70) is a potential cellular receptor for mdv glycoprotein gh. plaque inhibition assays confirm the involvement of hsp70 in the early stages of mdv entry into chicken embryo fibroblasts (cef). the present ... | 2011 | 21978152 |
| Recombinant herpesvirus of turkeys as a vector-based vaccine against highly pathogenic H7N1 avian influenza and Marek's disease. | A major challenge for poultry vaccination is the design of vaccines that protect against multiple pathogens via a single protective dose delivered through mass vaccination methods. In this investigation, we examined herpesvirus of turkeys (HVT) as a vaccine vector for delivery of haemagglutinin (HA) antigen of highly pathogenic H7N1 avian influenza virus that can act as a dual vaccine against avian influenza and Marek's disease. The HVT vector was developed using reverse genetics based on an inf ... | 2011 | 21907750 |
| temporal transcriptome changes induced by mdv in marek's disease-resistant and -susceptible inbred chickens. | abstract: background: mareks disease (md) is a lymphoproliferative disease in chickens caused by marek's disease virus (mdv) and characterized by t cell lymphoma and infiltration of lymphoid cells into various organs such as liver, spleen, peripheral nerves and muscle. resistance to md and disease risk have long been thought to be influenced both by genetic and environmental factors, the combination of which contributes to the observed outcome in an individual. we hypothesize that after mdv inf ... | 2011 | 21992110 |
| gene expression profiling in rmd5- and rmd5deltameq-infected chickens. | marek's disease (md) is a lymphoproliferative disorder of domestic chickens caused by a highly contagious and oncogenic alpha-herpesvirus, marek's disease virus (mdv). md is characterized by bursal-thymic atrophy and rapid onset of t-cell lymphomas that infiltrate lymphoid tissues, visceral organs, and peripheral nerves with severe clinical signs that include transient paralysis, anemia, weight loss, and neurologic disorders. using overlapping cosmids- and bac-cloned mdv, it has been shown that ... | 2011 | 22017031 |
| Herpesvirus telomerase RNA (vTR) with a mutated template sequence abrogates herpesvirus-induced lymphomagenesis. | Telomerase reverse transcriptase (TERT) and telomerase RNA (TR) represent the enzymatically active components of telomerase. In the complex, TR provides the template for the addition of telomeric repeats to telomeres, a protective structure at the end of linear chromosomes. Human TR with a mutation in the template region has been previously shown to inhibit proliferation of cancer cells in vitro. In this report, we examined the effects of a mutation in the template of a virus encoded TR (vTR) on ... | 2011 | 22046133 |
| systems analysis of immune responses in marek's disease virus-infected chickens identifies a gene involved in susceptibility and highlights a possible novel pathogenicity mechanism. | marek's disease virus (mdv) is a highly contagious oncogenic alphaherpesvirus that causes disease that is both a cancer model and a continuing threat to the world's poultry industry. this comprehensive gene expression study analyzes the host response to infection in both resistant and susceptible lines of chickens and inherent expression differences between the two lines following the infection of the host. a novel pathogenicity mechanism, involving the downregulation of genes containing hic1 tr ... | 2011 | 21865384 |
| rapid detection of marek's disease virus in feather follicles by loop-mediated amplification. | marek's disease (md) remains a serious problem in the production of poultry. the disease is caused by marek's disease virus (mdv), and despite the ubiquitous use of vaccination to control losses, md still affects poultry farming worldwide. the aim of this study was to develop a loop-mediated isothermal amplification (lamp) method for the simple and inexpensive detection of mdv in feather tips of chickens. two pairs of specific primers complementary to the meq oncogene of mdv were designed, targe ... | 2011 | 22017048 |
| surveillance of marek's disease virus in migratory and sedentary birds in hokkaido, japan. | marek's disease virus serotype 1 (mdv-1) strains cause malignant lymphoma in chickens. mdv-1 has been previously reported to be widespread in white-fronted geese (anser albifrons); however, the prevalence of mdv-1 in other wild birds has not been determined. in this study, we investigated the prevalence of mdv-1 in various wild birds in hokkaido, japan. the mdv-1 genome was widespread in geese and ducks, but was not detected in other birds. mdv-1 was detected in both sedentary and migratory spec ... | 2011 | 21908212 |
| mirna expression signatures induced by marek's disease virus infection in chickens. | micrornas (mirnas) are small, non-coding rnas that regulate gene expression at the post-transcriptional level. emerging evidence suggests that differential mirna expression is associated with viral infection and cancer. marek's disease virus infection induces lymphoma in chickens. however, the host defense response against marek's disease (md) progression remains poorly understood. here, we utilized microarrays to screen mirnas that were sensitive to marek's disease virus (mdv) infection. qrt-pc ... | 2011 | 22178800 |
| rapid detection of marek's disease viral genome in chicken feathers by loop mediated isothermal amplification (lamp). | a loop-mediated isothermal amplification (lamp) method for the rapid detection of serotype 1 marek's disease virus (mdv) was developed. the method used a set of three pairs of primers to amplify the meq gene for detecting serotype 1 mdv. the mdv lamp method did not cross-react with serotype 2 and serotype 3, nor did the lamp primers have binding sites for the common avian dna viruses (reticuloendotheliosis virus, chicken anemia virus, subgroup j of the avian leucosis virus). additionally, the as ... | 2011 | 22170920 |
| genome-wide identification and quantification of cis- and trans-regulated genes responding to marek's disease virus infection via analysis of allele-specific expression. | marek's disease (md) is a commercially important neoplastic disease of chickens caused by marek's disease virus (mdv), a naturally occurring oncogenic alphaherpesvirus. selecting for increased genetic resistance to md is a control strategy that can augment vaccinal control measures. to identify high-confidence candidate md resistance genes, we conducted a genome-wide screen for allele-specific expression (ase) amongst f(1) progeny of two inbred chicken lines that differ substantially in md resis ... | 2011 | 22303407 |
| Fluorescently tagged pUL47 of Marek's disease virus reveals differential tissue expression of the tegument protein in vivo. | Marek's disease virus (MDV), a lymphotropic alphaherpesvirus, causes Marek's disease (MD) in chickens. MD is characterized by neurological signs, chronic wasting, and T cell lymphomas that predominate in the visceral organs. MDV replicates in a highly cell-associated manner in vitro and in vivo, with infectious virus particles only being released from feather follicle epithelial (FFE) cells in the skin. Virus produced and shed from FFE cells allows transmission of MDV from infected to naïve chic ... | 2011 | 22190714 |
| marek's disease virus late protein expression in feather follicle epithelial cells as early as 8 days postinfection. | marek's disease virus (mdv) or gallid herpesvirus 2 (gahv-2) is a lymphotropic alphaherpesvirus and causes marek's disease. former studies have demonstrated that mdv is spread from chicken to chicken about 2 wk postexposure as infectious dander shed from infected chickens. more recent reports, using highly sensitive quantitative pcr analyses of dander from infected chickens, suggested that mdv replicates and is shed from the chicken much earlier (5-7 days). however, detection of viral dna in chi ... | 2012 | 23397845 |
| histone methylation analysis and pathway predictions in chickens after mdv infection. | marek's disease (md) is a lymphoproliferative disease in chicken induced by marek's disease virus (mdv). although studies have focused on the genetic differences between the resistant and susceptible chicken, less is known about the role of epigenetic factors in md. in this study, genome-wide histone modifications in the non-mhc-associated resistant and susceptible chicken lines were examined. we found that tri-methylation at histone h3 lys4 (h3k4me3) enrichment is positively correlated with the ... | 2012 | 22848633 |
| effects of interferon-γ knockdown on vaccine-induced immunity against marek's disease in chickens. | interferon (ifn)-γ has been shown to be associated with immunity to marek's disease virus (mdv). the overall objective of this study was to investigate the causal relationship between ifn-γ and vaccine-conferred immunity against mdv in chickens. to this end, 3 small interfering rnas (sirnas) targeting chicken ifn-γ, which had previously been shown to reduce ifn-γ expression in vitro, and a control sirna were selected to generate recombinant avian adeno-associated virus (raaav) expressing short-h ... | 2015 | 25673902 |
| spontaneous spinal plexiform perineurioma in a juvenile chicken ( gallus domesticus). | a 2-mo-old pet chicken ( gallus domesticus) was presented because of lameness and a hind limb mass of 1 mo duration. radiographs revealed a soft tissue mass extending from the mid-femur into the body wall. cytology of a sample obtained from a fine-needle aspirate was unremarkable. the bird was prepared for surgical investigation of the mass but died acutely at the time of pre-medication. autopsy revealed an extradural mesenchymal neoplasm that focally compressed the lumbar spinal cord, extended ... | 2017 | 28381111 |
| history of the first-generation marek's disease vaccines: the science and little-known facts. | shortly after the isolation of marek's disease (md) herpesvirus (mdv) in the late 1960s vaccines were developed in england, the united states, and the netherlands. biggs and associates at the houghton poultry research station (hprs) in england attenuated hprs-16, the first cell-culture-isolated mdv strain, by passaging hprs-16 in chick kidney cells. although hprs-16/att was the first commercially available vaccine, it never became widely used and was soon replaced by the fc126 strain of herpesvi ... | 2016 | 27902902 |
| recombinant marek's disease virus as a vector-based vaccine against avian leukosis virus subgroup j in chicken. | avian leukosis virus subgroup j (alv-j) is an immunosuppressive virus that causes considerable economic losses to the chicken industry in china. however, there is currently no effective vaccine to prevent alv-j infection. in order to reduce the losses caused by alv-j, we constructed two effective alv-j vaccines by inserting the alv-j (strain jl093-1) env or gag+env genes into the us2 gene of the marek's disease herpesviruses (mdv) by transfection of overlapping fosmid dnas, creating two recombin ... | 2016 | 27827933 |
| gp85 genetic diversity of avian leukosis virus subgroup j among different individual chickens from a native flock. | to compare the genetic diversity and quasispecies evolution of avian leukosis virus (alv) among different individuals, 5 chickens, raised in shandong provice of china, were randomly selected from a local chicken flock associated with serious tumor cases. blood samples were collected and inoculated into chicken embryo fibroblast and df-1 cell lines for virus isolation and identification, respectively, of marek's disease virus (mdv), reticuloendotheliosis virus (rev), and alv. five strains of alv ... | 2016 | 27794054 |
| expression patterns of endogenous avian retrovirus alve1 and its response to infection with exogenous avian tumour viruses. | endogenous retroviruses (ervs) are genomic elements that are present in a wide range of vertebrates and have been implicated in a variety of human diseases, including cancer. however, the characteristic expression patterns of ervs, particularly in virus-induced tumours, is not fully clear. dna methylation was analysed by bisulfite pyrosequencing, and gene expression was analysed by rt-qpcr. in this study, we first found that the endogenous avian retrovirus alve1 was highly expressed in some chic ... | 2017 | 27686071 |
| emergence of reticuloendotheliosis virus in pigeons in guangdong province, southern china. | reticuloendotheliosis virus (rev), an important immunosuppressive pathogen, has many hosts, including chickens, ducks, geese, turkeys, and wild birds. clinically, rev may lead to increased susceptibility to other pathogens, resulting in serious tissue damage (especially tumors) and the death of its host. in this study, we encountered a disease outbreak resulting in a large number of deaths of pigeons in guangdong province, southern china. histopathological analysis revealed apparent tumor-like l ... | 2016 | 27120185 |
| expression of the env gene from the avian endogenous retrovirus alve and regulation by mir-155. | endogenous retroviruses (ervs) are important retroelements that reside in host genomes. however, erv expression patterns and regulatory mechanisms are poorly understood. in this study, chicken embryo fibroblasts (cefs) and msb1 cells infected with marek's disease virus (mdv) exhibited significantly increased expression of env from the endogenous retrovirus alve. in contrast, env expression was significantly lower in cef and msb1 cells infected with exogenous avian leukosis virus j (alvj) at the ... | 2016 | 27016933 |
| isolation and pathogenic analysis of virulent marek's disease virus field strain in china. | marek's disease (md) has become increasingly common in china, resulting in considerable economic loss. the etiological agent is unclear. in this study, we isolated a field md virus (mdv) strain, designated sx1301, from cvi988/rispens-vaccinated chickens with tumors. co-infection of avian leukosis virus, reticuloendotheliosis virus, and chicken infectious anemia virus was excluded by polymerase chain reaction, enzyme-linked immunosorbant assay, dna blotting hybridization, and indirect immunofluor ... | 2016 | 26976907 |
| influence of avian leukosis virus long terminal repeat on biological activities of marek's disease virus. | gx0101 was the first reported field strain of recombinant marek's disease virus (mdv) that contained a long terminal repeat (ltr) from the reticuloendotheliosis virus (rev). it is a very virulent mdv strain, with relatively high horizontal transmission ability. the rev ltr in gx0101 genome was proved to decrease the pathogenicity but increase the potential for horizontal transmission of the virus. here we constructed a recombinant mdv gx0101-alv-ltr to study stability of avian leukosis virus (al ... | 2015 | 26274570 |
| pathotyping of recent indian field isolates of marek's disease virus serotype 1. | a study was undertaken to assess the virulence of marek's disease virus (mdv) serotype 1 field isolates obtained from poultry flocks of southern part of india. five representative mdv serotype 1 strains were isolated from eighty-six blood samples collected from fifteen farms. three out of five isolates which were free from avian leukosis virus (alv) and reticuloendotheliosis virus (rev) were adapted in chicken embryo fibroblast (cef) culture and designated as ind/tn/11/01, ind/ka/12/02 and ind/t ... | 2015 | 26104332 |
| lack of evidence that avian oncogenic viruses are infectious for humans: a review. | chickens may be infected with three different oncogenic viruses: avian leukosis virus (alv), reticuloendotheliosis virus (rev), and marek's disease herpesvirus (mdv). several epidemiological studies have suggested a link between these viruses and different types of cancer in people working in poultry processing plants and with multiple sclerosis. in this article, we analyze the epidemiological evidence that these viruses are causative agents for human cancer, followed by description of the relev ... | 2014 | 25518427 |
| further observations on serotype 2 marek's disease virus-induced enhancement of spontaneous avian leukosis virus-like bursal lymphomas in alva6 transgenic chickens. | breeders of the 2009 generation of avian disease and oncology laboratory transgenic chicken line alva6, known to be resistant to infection with subgroups a and e avian leukosis virus (alv), were vaccinated at hatch with a trivalent marek's disease (md) vaccine containing serotypes 1, 2, and 3 marek's disease virus (mdv) and were maintained under pathogen-free conditions from the day of hatch until 75 weeks of age. spontaneous alv-like bursal lymphomas, also termed lymphoid leukosis (ll)-like lym ... | 2015 | 25407937 |
| avian oncogenic virus differential diagnosis in chickens using oligonucleotide microarray. | avian oncogenic viruses include the avian leukosis virus (alv), reticuloendotheliosis virus (rev) and marek's disease virus (mdv). multiple oncogenic viral infections are frequently seen, with even marek's disease vaccines reported to be contaminated with alv and rev. the gross lesions caused by avian oncogenic viruses often overlap, making differentiation diagnosis based on histopathology difficult. the objective of this study is to develop a rapid approach to simultaneously differentiate, subg ... | 2014 | 25286179 |
| avian gyrovirus 2 and avirulent newcastle disease virus coinfection in a chicken flock with neurologic symptoms and high mortalities. | a disease with severe neurologic symptoms caused 100% mortality in a small broiler operation in the gauteng province, south africa in late march 2013. routine diagnostic pcr testing failed to identify a possible cause of the outbreak; thus, samples were submitted for virus isolation, serology, and bacteriology. an avirulent newcastle disease virus (ndv) strain isolated was identified as a v4-like genotype 1 strain, by dna sequencing, with a cleavage site of 112gkqgr decrease l117. real-time reve ... | 2014 | 24758119 |
| role of virus-encoded micrornas in avian viral diseases. | with total dependence on the host cell, several viruses have adopted strategies to modulate the host cellular environment, including the modulation of microrna (mirna) pathway through virus-encoded mirnas. several avian viruses, mostly herpesviruses, have been shown to encode a number of novel mirnas. these include the highly oncogenic marek's disease virus-1 (26 mirnas), avirulent marek's disease virus-2 (36 mirnas), herpesvirus of turkeys (28 mirnas), infectious laryngotracheitis virus (10 mir ... | 2014 | 24662606 |
| skin involvement in lymphomas caused by marek's disease virus infection in silkie chickens. | the silkie is a typical chinese breed of chicken. in 2012, batches of silkies were found to have diffuse tumor-like nodules on their skin after feather removal, when they were slaughtered at about 60 days old. gross examination showed no visible neoplastic lesions on the visceral organs and peripheral nerves, except slight splenomegaly in individual chickens. the disease was prevalent, with high condemnation rates for skin lesions, which caused great economic losses to the company. tissues, incl ... | 2014 | 24583947 |
| avian leukosis virus subgroup j associated with the outbreak of erythroblastosis in chickens in china. | emaciation, depression and lethargy were observed in two flocks of chinese local breed and one flock of commercial layer chicken infected naturally from 2010 to 2011. the aims of this study were to diagnose. | 2013 | 23521848 |
| development of an antigen-capture elisa for the detection of avian leukosis virus p27 antigen. | an antigen-capture enzyme-linked immunosorbent assay (ac-elisa) employing monoclonal and polyclonal antibodies against p27 was developed for the detection of the avian leukosis virus (alv). the specificity of the optimized ac-elisa was evaluated using avian leukosis virus subgroup j (alv-j), avian leukosis virus subgroup a (alv-a), avian leukosis virus subgroup b (alv-b), avian infectious bronchitis virus (ibv), marek's disease virus (mdv), avian infectious laryngotracheitis virus (iltv), fowlpo ... | 2013 | 23201286 |
| differential detection of avian oncogenic viruses in poultry layer farms and turkeys by use of multiplex pcr. | avian oncogenic viruses include marek's disease virus (mdv), a highly contagious herpesvirus, as well as retroviruses such as avian leukosis virus (alv) subgroups a to j and reticuloendotheliosis virus (rev). in this study, we examined the incidence of these viruses in suspected samples collected from poultry layer farms of south india, mainly in the namakkal district of tamil nadu, a highly dense poultry-growing area in india. the histopathology-positive tissue sections were identified and furt ... | 2012 | 22675132 |
| establishment of an immortal chicken embryo liver-derived cell line. | a continuously growing immortal cell substrate can be used for virus propagation, diagnostic purposes, and vaccine production. the aim of this study was to develop an immortal chicken cell line for efficient propagation of avian infectious viruses. from the various chicken embryo cells that were tested for life span extension, an immortalized chicken embryo liver (cel) cell line, named cel-im, was derived spontaneously without either oncogenic viruses or carcinogenic chemical treatment. currentl ... | 2013 | 23687157 |
| simultaneous detection of eight immunosuppressive chicken viruses using a gexp analyser-based multiplex pcr assay. | immunosuppressive viruses are frequently found as co-infections in the chicken industry, potentially causing serious economic losses. because traditional molecular biology methods have limited detection ability, a rapid, high-throughput method for the differential diagnosis of these viruses is needed. the objective of this study is to develop a genomelab gene expression profiler analyser-based multiplex pcr method (gexp-multiplex pcr) for simultaneous detection of eight immunosuppressive chicken ... | 2015 | 26715327 |
| detection of infectious laryngotracheitis virus by real-time pcr in naturally and experimentally infected chickens. | infectious laryngotracheitis (ilt) is an acute, highly contagious upper-respiratory infectious disease of chickens. in this study, a real-time pcr method was developed for fast and accurate detection and quantitation of iltv dna of chickens experimentally infected with iltv strain ljs09 and naturally infected chickens. the detection lower limit of the assay was 10 copies of dna. there were no cross reactions with the dna and rna of infectious bursal disease virus, chicken anemia virus, reticuloe ... | 2013 | 23840745 |
| understanding the molecular basis of disease is crucial to improving the design and construction of herpesviral vectors for veterinary vaccines. | viral infections are associated with production losses in many animal production industries. important examples of this are marek's disease (md) and bovine respiratory disease (brd) which are significant issues in the chicken and cattle industries, respectively. viruses play key roles in md and brd development and consequently have also been utilised in vaccination strategies to control these diseases. despite the widespread availability and use of vaccines to control these diseases both are sti ... | 2015 | 26387436 |
| full-length infectious clone of an iranian isolate of chicken anemia virus. | an iranian field strain of chicken anemia virus (cav), designated ir cav, was isolated in the marek's disease virus-transformed lymphoblastoid cell line mdcc-msb1 (msb1) culture for the first time. the full-length cav dna of this strain was cloned in the bacterial plasmid ptz57r/t to create the molecular clone ptz-cav. the nucleotide and deduced amino acid sequences of viral proteins of ir cav were compared with those of representative cav sequences including reference and commercial vaccine str ... | 2017 | 27933433 |
| persistence of chicken anemia virus antigen and inclusions in spontaneous cases of marek's disease visceral lymphomas in broiler chickens at slaughterhouses. | the chicken anemia virus (cav) and marek's disease virus (mdv) infect chickens worldwide; a single or dual infection by these viruses has a great impact on poultry production. in the present study, we examined the existence of cav antigen and its inclusions in marek's disease (md) lymphomas in chickens in the slaughterhouses of iwate prefecture, japan. forty-nine spleens and 13 livers with different degrees of nodular lesions were histopathologically examined at our laboratory. grossly, the test ... | 2016 | 26888585 |
| development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus. | a blocking latex agglutination test (b-lat) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (cav) in chickens. polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mab) to cav (mab-beads). when mab-beads were mixed with antigens prepared from the lysate of mdcc-msb1 cells infected with cav, agglutination occurred. a short pre-incubation of cav antigens with cav-specific antiserum inhibited the agglutination of mab-beads. ... | 2015 | 25952731 |
| application of cross-priming amplification (cpa) for detection of fowl adenovirus (fadv) strains. | fowl adenoviruses (fadvs) are widely distributed among chickens. detection of fadvs is mainly accomplished by virus isolation, serological assays, various polymerase chain reaction (pcr) assays, and loop-mediated isothermal amplification (lamp). to increase the diagnostic capacity of currently applied techniques, cross-priming amplification (cpa) for the detection of the fadv hexon gene was developed. the single cpa assay was optimised to detect all serotypes 1-8a-8b-11 representing the species ... | 2015 | 25655263 |
| quantitation of marek's disease and chicken anemia viruses in organs of experimentally infected chickens and commercial chickens by multiplex real-time pcr. | the worldwide distribution of chicken anemia virus (cav) and marek's disease virus (mdv) is well documented. in addition to their economic significance in single- or dual-virus infections, the two viruses can often accompany various other pathogens and affect poultry health either directly, by causing tumors, anemia, and delayed growth, or indirectly, by aggravating other diseases, as a result of their immunosuppressive effects. after a decade of employing the molecular diagnosis of those viruse ... | 2013 | 23901772 |
| development of a chick bioassay for determination of infectivity of viral pathogens in poultry litter. | to develop a chicken bioassay to detect infective viral pathogens in poultry litter and to determine the effects of type of chicken and age of exposure, as well as the effect of simulated litter transportation, on the level of viral infectivity detected. | 2013 | 23356376 |
| a comparative evaluation of the protective efficacy of rmd5deltameq and cvi988/ rispens against a vv+ strain of marek's disease virus infection in a series of recombinant congenic strains of white leghorn chickens. | marek's disease (md) is a lymphoproliferative disease of domestic chickens caused by a highly infectious, oncogenic alpha-herpesvirus known as marek's disease virus (mdv). md is presently controlled by vaccination. current md vaccines include attenuated serotype 1 strains (e.g., cvi988/rispens), avirulent serotype 2 (sb-1), and serotype 3 (hvt) mdv strains. in addition, recombinant mdv strains have been developed as potential new and more efficient vaccines to sustain the success of md control i ... | 2011 | 22017035 |
| avian influenza adenovirus-vectored in ovo vaccination: target embryo tissues and combination with marek's disease vaccine. | we investigated embryo tissues targeted by replication competent adenovirus (ad)-free recombinant ad expressing a codon-optimized avian influenza (ai) h5 gene from a/turkey/wi/68 (adh5) when injected into 18-day embryonated eggs. we also evaluated the effects of concurrent in ovo vaccination with the experimental adh5 vaccine and commercially available marek's disease virus (mdv) vaccine combinations rispens/turkey herpesvirus (hvt) or hvt/sb-1. computed tomography indicates that in ovo injectio ... | 2011 | 22312988 |
| [proteomics analysis of feather pulp from chickens infected with very virulent strain of marek's disease virus]. | feather follicle epithelium (ffe) and feather of chicken are sites that produce and release enveloped infectious marek's disease virus (mdv). in order to investigate host responses, the feather pulp from chickens infected with mdv was analyzed by proteomics. | 2011 | 22233062 |
| construction of recombinant hvt expressing pmpd, and immunological evaluation against chlamydia psittaci and marek's disease virus. | chlamydia psittaci (c. psittaci) is an obligate intracellular zoonotic pathogen that can be transmitted to humans from birds. no efficacious commercial vaccine is available for clearing chlamydial infection due to lack of potential vaccine candidates and effective delivery vehicles. herpesvirus of turkeys (hvt) is an efficacious commercially available vaccine against marek's disease virus (mdv). in this study, a recombinant hvt-delivered vaccine against c. psittaci and marek's disease was develo ... | 2015 | 25893439 |
| effects of different promoters on the protective efficacy of recombinant marek's disease virus type 1 expressing the vp2 gene of infectious bursal disease virus. | the vaccine efficacy of recombinant viruses can be influenced by many factors. accordingly, the activity of promoters has been one of the major factors affecting the antigen expression and protection rate. in the present study, two recombinant marek's disease virus type 1 (mdv1) vaccines containing the vp2 gene of infectious bursal disease virus (ibdv) under control of different promoters were generated from overlapping fosmid dnas. the rmdv-pec-vp2 virus containing the vp2 gene under control of ... | 2016 | 27742216 |
| [construction of recombinant marek's disease virus expressing the ndv-f gene and its replication in chickens and in vitro]. | we used a meq-deleted attenuated mdv-i strain gx0101δmeq as a vector to construct a recombinant virus expressing the exogenous gene ndv-f. the orf of exogenous gene ndv-f was inserted into the eukaryotic expression vector pcdna3.1(-). then, the expression cassette of ndv-f which contains the cmv promoter was amplified. simultaneously, we amplified the selected gene kan+ expression cassette and inserted them into the pmd18-t vector. tandem expression cassettes were amplified using primers contain ... | 2015 | 26524905 |
| construction of recombinant marek's disease virus (mdv) lacking the meq oncogene and co-expressing aiv-h9n2 ha and na genes under control of exogenous promoters. | to develop a recombinant marek's disease virus (rmdv1) co-expressing the hemagglutinin gene (ha) and neuramidinase gene (na) from a low pathogenic avian influenza virus (lpaiv) h9n2 strain and lacking the meq oncogene that shares homology with the jun/fos family of transcriptional factors, a wild strain of mdv gx0101 was used as parental virus, the ha and na genes co-expression cassette under control of the cmv and sv40 early promoters was inserted at two meq sites of gx0101 to form a new meq kn ... | 2014 | 24709399 |
| avirulent marek's disease virus type 1 strain 814 vectored vaccine expressing avian influenza (ai) virus h5 haemagglutinin induced better protection than turkey herpesvirus vectored ai vaccine. | herpesvirus of turkey (hvt) as a vector to express the haemagglutinin (ha) of avian influenza virus (aiv) h5 was developed and its protection against lethal marek's disease virus (mdv) and highly pathogenic aiv (hpaiv) challenges was evaluated previously. it is well-known that avirulemt mdv type 1 vaccines are more effective than hvt in prevention of lethal mdv infection. to further increase protective efficacy against hpaiv and lethal mdv, a recombinant mdv type 1 strain 814 was developed to ex ... | 2013 | 23301062 |
| chicken gga-mir-103-3p targets ccne1 and tfdp2 and inhibits mdcc-msb1 cell migration. | marek's disease (md) is a highly contagious viral neoplastic disease caused by marek's disease virus (mdv), which can lead to huge economic losses in the poultry industry. recently, micrornas (mirnas) have been found in various cancers and tumors. in recent years, 994 mature mirnas have been identified through deep sequencing in chickens, but only a few mirnas have been investigated further in terms of their function. previously, gga-mir-103-3p was found downregulated in mdv-infected samples by ... | 2016 | 26935418 |
| molecular detection of avian pathogens in poultry red mite (dermanyssus gallinae) collected in chicken farms. | poultry red mite (prm, dermanyssus gallinae) is a blood-sucking ectoparasite as well as a possible vector of several avian pathogens. in this study, to define the role of prm in the prevalence of avian infectious agents, we used polymerase chain reaction (pcr) to check for the presence of seven pathogens: avipox virus (apv), fowl adenovirus (fadv), marek's disease virus (mdv), erysipelothrix rhusiopathiae (er), salmonella enterica (se), mycoplasma synoviae (ms) and mycoplasma gallisepticum (mg). ... | 2014 | 25649939 |
| evaluation of the protection efficacy of a serotype 1 marek's disease virus-vectored bivalent vaccine against infectious laryngotracheitis and marek's disease. | laryngotracheitis (lt) is a highly contagious respiratory disease of chickens that produces significant economic losses to the poultry industry. traditionally, lt has been controlled by administration of modified live vaccines. in recent years, the use of recombinant dna-derived vaccines using turkey herpesvirus (hvt) and fowlpox virus has expanded, as they protect not only against the vector used but also against lt. however, hvt-based vaccines confer limited protection against challenge, with ... | 2015 | 26473676 |
| the peptide motif of the single dominantly expressed class i molecule of the chicken mhc can explain the response to a molecular defined vaccine of infectious bursal disease virus (ibdv). | in contrast to typical mammals, the chicken mhc (the bf-bl region of the b locus) has strong genetic associations with resistance and susceptibility to infectious pathogens as well as responses to vaccines. we have shown that the chicken mhc encodes a single dominantly expressed class i molecule whose peptide-binding motifs can determine resistance to viral pathogens, such as rous sarcoma virus and marek's disease virus. in this report, we examine the response to a molecular defined vaccine, fp- ... | 2013 | 23644721 |
| evaluation of factors influencing the development of late marek's disease virus-induced immunosuppression: virus pathotype and host sex. | marek's disease virus (mdv) is a herpesvirus that induces lymphoma and immunosuppression in chickens. mdv induced immunosuppression (mdv-is) is complex and can be divided into two phases: early-mdv-is associated with cytolytic infection in the lymphoid organs in chickens lacking maternal antibodies against mdv (mabs) and late-mdv-is that appears later in the pathogenesis and occurs even in chickens bearing mabs. we have recently developed a model to reproduce late-mdv-is under laboratory conditi ... | 2017 | 28151004 |
| current and future vaccines and vaccination strategies against infectious laryngotracheitis (ilt) respiratory disease of poultry. | infectious laryngotracheitis (ilt) is an economically important respiratory disease of poultry that affects the industry worldwide. vaccination is the principal tool in the control of the disease. two types of vaccines, live attenuated and recombinant viral vector, are commercially available. the first generation of gahv-1 vaccines available since the early 1960's are live viruses, attenuated by continuous passages in cell culture or embryos. these vaccines significantly reduce mortalities and, ... | 2016 | 28057380 |
| early infection with marek's disease virus can jeopardize protection conferred by laryngotracheitis vaccines: a method to study mdv-induced immunosuppression. | marek's disease virus (mdv) is a herpesvirus that induces lymphomas and immunosuppression in chickens. mdv-induced immunosuppression (mdv-is) is divided into two phases: early-mdv-is occurring mainly in chickens lacking maternal antibodies (mab) against mdv and associated with lymphoid organ atrophy; and late-mdv-is occurring once mdv enters latency and during tumour development. our objectives were to document the impact of late-mdv-is on commercial poultry (meat-type chickens bearing mab again ... | 2016 | 27207594 |
| efficacy of various marek's disease vaccines protocols for prevention of marek's disease virus-induced immunosuppression. | marek's disease virus (mdv) induces tumors and severe immunosuppression in chickens. mdv-induced immunosuppression (mdv-is) is very complex and difficult to study. in particular, the late mdv-is (late-mdv-is) is of great concern since it can occur in the absence of lymphoid organ atrophy or gross tumors. we have recently developed a model to reproduce late-mdv-is under laboratory conditions. this model measures mdv-is indirectly by assessing the effect of mdv infection on the efficacy of infecti ... | 2016 | 27371103 |
| a chinese variant marek's disease virus strain with divergence between virulence and vaccine resistance. | marek's disease (md) virus (mdv) has been evolving continuously, leading to increasing vaccination failure. here, the mdv field strain bs/15 was isolated from a severely diseased chinese chicken flock previously vaccinated with cvi988. to explore the causes of vaccination failure, specific-pathogen free (spf) chickens vaccinated with cvi988 or 814 and unvaccinated controls were challenged with either bs/15 or the reference strain md5. both strains induced md lesions in unvaccinated chickens with ... | 2017 | 28368367 |
| early immune responses to marek's disease vaccines. | marek's disease virus (mdv), a highly cell-associated lymphotropic α-herpesvirus, is the causative agent of marek's disease (md) in domestic chickens. mdv replicates in chicken cells and establishes a latent infection within cd4(+) t cells. although md vaccines have been in use for several decades, the exact mechanism of vaccine-induced protection is unclear. it is believed that the innate immune system plays a role in vaccine-induced immunity against pathogenic strains of mdv. to shed light on ... | 2017 | 28346793 |
| evaluation and identification of marek's disease virus bac clones as standardized reagents for research. | marek's disease virus (mdv) is an alphaherpesvirus that causes marek's disease (md), a lymphoproliferative disease in chickens. understanding of mdv gene function advanced significantly following the cloning of the mdv genome as either a series of overlapping cosmids or as a bacterial artificial chromosome (bac), both of which could produce viable mdv. the objectives of this study were to compare multiple virulent mdv bac clones using the avian disease and oncology laboratory's pathotyping assay ... | 2017 | 28301231 |
| characterization of a gallid herpesvirus 2 strain with novel reticuloendotheliosis virus long terminal repeat inserts. | a bacterial artificial chromosome clone, designated lcy, was constructed from a gallid herpesvirus 2 (gahv-2) isolate from a gahv-2 and reticuloendotheliosis virus co-infected clinical sample. the lcy gahv-2 insert was sequenced and found to consist of 175,319 nucleotides. lcy gahv-2 open reading frames (orfs) had a high sequence identity to those of reference strains. the major difference was that two rev long terminal repeats (ltrs), in the same direction, were inserted at the internal repeat ... | 2017 | 28194622 |
| expression of marek's disease virus oncoprotein meq during infection in the natural host. | gallid herpesvirus 2 (marek's disease virus, mdv) causes lymphoproliferative marek's disease (md), and is unique among alphaherpesviruses as the viral genome encodes an oncoprotein, meq. to elucidate the temporal relationship between meq expression and the development of md lymphomas in infected chickens, we generated a virulent recombinant mdv that expresses gfp simultaneously with meq. by using this virus, we monitored the dynamics of meq expression in vivo throughout the course of infection. ... | 2017 | 28160668 |
| activation of gga-mir-155 by reticuloendotheliosis virus t strain and its contribution to transformation. | the v-rel oncoprotein encoded by reticuloendotheliosis virus t strain (rev-t) is a member of the rel/nf-κb family of transcription factors capable of transformation of primary chicken spleen and bone marrow cells. rapid transformation of avian haematopoietic cells by v-rel occurs through a process of deregulation of multiple protein-encoding genes through its direct effect on their promoters. more recently, upregulation of oncogenic mir-155 and its precursor pre-mir-155 were demonstrated in rev- ... | 2017 | 28113043 |
| recombinant marek's disease virus type 1 provides full protection against very virulent marek's and infectious bursal disease viruses in chickens. | marek's disease virus (mdv) is a preferred vector in the construction of recombinant vaccines. however, bivalent vaccine based on mdv that confers full protection against both very virulent marek's and infectious bursal disease virus (ibdv) infections in chickens has not been produced. here we developed a system utilizing overlapping fosmid dnas transfection that rescues an mdv type 1 (mdv1) vaccine strain. using this system, we inserted the ibdv vp2 gene at mdv1 genome sites ul41, us10 and us2. ... | 2016 | 27982090 |
| investigation of marek's disease virus from chickens in central ethiopia. | marek's disease (md) is a lymphoproliferative and neuropathic disease of domestic chickens and less commonly, turkeys and quails, caused by a highly contagious, cell-associated, oncogenic herpesvirus. in ethiopia, md is believed to be introduced with importation of exotic and crossbred to improve the poultry production and has been reported to be a potential threat to the poultry sector both in backyard and commercial farming systems. this study was aimed at isolation and molecular analysis of m ... | 2017 | 27975190 |
| turkey herpesvirus with an insertion in the ul3-4 region displays an appropriate balance between growth activity and antibody-eliciting capacity and is suitable for the establishment of a recombinant vaccine. | we constructed turkey herpesvirus (hvt) vector vaccines in which the vp2 gene of infectious bursal disease virus (ibdv) was inserted into the hvt genome in the following regions: ul3-4, ul22-23, ul45-46, and us10-sorf3. we then evaluated the relationship between the gene insertion site and the capacity of the virus to elicit antibodies. rhvt/ibd (us10) showed good growth activity in vitro, with growth comparable to that of the parent hvt. on the other hand, rhvt/ibd (ul3-4), rhvt/ibd (ul22-23), ... | 2017 | 27942974 |
| evaluation of two strains of marek's disease virus serotype 1 for the development of recombinant vaccines against very virulent infectious bursal disease virus. | attenuated strains of marek's disease virus serotype 1 (mdv1), and the closely related herpesvirus of turkeys, are among the most potent vectors for development of recombinant vaccines for poultry. to investigate the effects of mdv1 strain characteristics on the protective efficacy of the recombinant vaccines, we developed two recombinant mdv1 vaccines for expressing the vp2 gene of infectious bursal disease virus (ibdv) based on two different mdv1 strains, the attenuated strain 814 and the meq ... | 2017 | 27908832 |
| marek's disease in backyard chickens, a study of pathologic findings and viral loads in tumorous and nontumorous birds. | marek's disease (md) is a major cause of mortality in backyard chickens. the diagnosis of md is complex, however, and knowledge of marek's disease virus (mdv) in spontaneous field cases such as in backyard chickens is largely unknown. in this study, 40 backyard chickens with a presumptive md diagnosis based on histologic lymphoid infiltrations in peripheral nerves with and without lymphomas were investigated. twenty-eight of the birds were submitted to the diagnostic laboratory for disease explo ... | 2016 | 27902909 |
| marek's disease in chickens: a review with focus on immunology. | marek's disease (md), caused by marek's disease virus (mdv), is a commercially important neoplastic disease of poultry which is only controlled by mass vaccination. importantly, vaccines that can provide sterile immunity and inhibit virus transmission are lacking; such that vaccines are only capable of preventing neuropathy, oncogenic disease and immunosuppression, but are unable to prevent mdv transmission or infection, leading to emergence of increasingly virulent pathotypes. hence, to address ... | 2016 | 27894330 |
| protective efficacy of a recombinant bacterial artificial chromosome clone of a very virulent marek's disease virus containing a reticuloendotheliosis virus long terminal repeat. | marek's disease virus (mdv), an alphaherpesvirus, causes marek's disease (md), a lymphoproliferative disease in poultry characterized by t-cell lymphomas, nerve lesions, and mortality. vaccination is used worldwide to control md, but increasingly virulent field strains can overcome this protection, driving a need to create new vaccines. previous studies revealed that insertion of reticuloendotheliosis virus (rev) long terminal repeat (ltr) into a bacterial artificial chromosome (bac) clone of a ... | 2016 | 27258614 |
| marek's disease herpesvirus vaccines integrate into chicken host chromosomes yet lack a virus-host phenotype associated with oncogenic transformation. | marek's disease (md) is a lymphotropic and oncogenic disease of chickens that can lead to death in susceptible and unvaccinated host birds. the causative pathogen, md virus (mdv), a highly oncogenic alphaherpesvirus, integrates into host genome near the telomeres. md occurrence is controlled across the globe by biosecurity, selective breeding for enhanced md genetic resistance, and widespread vaccination of flocks using attenuated serotype 1 mdv or other serotypes. despite over 40 years of usage ... | 2016 | 27720297 |
| isolation and purification of gallid herpesvirus 2 strains currently distributed in japan. | gallid herpesvirus 2 (gahv-2) causes malignant lymphomas in chickens (marek's disease, md). although md is controlled through vaccination efforts, field isolates of gahv-2 have increased in virulence worldwide and even cause md in vaccinated chickens. gahv-2 strains are classified into four categories (mild, virulent, very virulent and very virulent +) based on the virulence exhibited in experimental infection in unvaccinated or md-vaccinated susceptible chickens. although md cases are sporadica ... | 2017 | 27725354 |
| marek's disease virus immunosuppression alters host cellular responses and immune gene expression in the skin of infected chickens. | marek's disease virus (mdv), a highly cell-associated lymphotropic α-herpesvirus, is the causative agent of marek's disease (md) in domestic chickens. mdv replicates in chicken lymphocytes and establishes a latent infection within cd4(+) t cells. the latently infected cd4(+) t cells carry the virus to visceral organs, peripheral nerves, and feather follicle epithelium (ffe). ffe is the only anatomical site where infectious enveloped cell-free virus particles are produced and disseminated into th ... | 2016 | 27692091 |
| hyperediting by adar1 of a new herpesvirus lncrna during the lytic phase of the oncogenic marek's disease virus. | marek's disease virus, or gallid herpesvirus 2 (gahv-2), is an avian alphaherpesvirus that induces t-cell lymphoma in chickens. during transcriptomic studies of the rl region of the genome, we characterized the 7.5 kbp gene of the erl lncrna (edited repeat-long, long non-coding rna), which may act as a natural antisense transcript (nat) of the major gahv-2 oncogene meq and of two of the three mirna clusters. during infections in vivo and in vitro, we detected hyperediting of the erl lncrna that ... | 2016 | 27655063 |
| sequence analysis of meq oncogene among indian isolates of marek's disease herpesvirus. | marek's disease (md), caused by marek's disease virus (mdv), is a highly contagious neoplastic disease of chicken that can be prevented by vaccination. however, in recent years many cases of vaccine failure have been reported worldwide as chickens develop symptoms of md in spite of proper vaccination. distinct polymorphism and point mutations in meq gene of mdv have been reported to be associated with virulence and oncogenicity. the present study was carried out with the objective to isolate and ... | 2016 | 27617224 |
| natural infection with avian hepatitis e virus and marek's disease virus in brown layer chickens in china. | in the present study, avian hepatitis e virus (hev) and serotype-1 strains of marek's disease virus (mdv-1) were detected from a flock of 27-wk-old brown layer hens in china, accompanied by an average daily mortality of 0.44%. postmortem examination of 25 sick hens and five apparently healthy hens selected randomly from the flock showed significant pathologic changes consistent with hepatitis-splenomegaly syndrome (hss), including hepatomegaly, peritoneal fluid, and hepatic subcapsular hemorrhag ... | 2016 | 27610734 |
| development and evaluation of the protective efficacy of novel marek's disease virus rispens vector vaccines against infectious bursal disease. | infectious bursal disease (ibd) is a major disease affecting the poultry industry and is caused by infection with ibd virus (ibdv). to develop a novel vaccine to prevent ibd in chickens, recombinant marek's disease virus rispens viruses carrying the vp2 gene of ibdv driven by five different promoters (rispens/ibd) were constructed using homologous recombination and a bacterial artificial chromosome (bac). rispens/ibd driven by the chicken beta-actin (bac) promoter (rispens/bac-ibd), rous sarcoma ... | 2016 | 27610721 |
| differences in cd8αα and cecal microbiome community during proliferation and late cytolytic phases of marek's disease virus infection are associated with genetic resistance to marek's disease. | marek's disease (md) is an important neoplastic disease of chickens caused by marek ': s disease virus (mdv), a highly oncogenic alphaherpesvirus. in this study using two chicken lines, one resistant and another susceptible to md, splenic t cells and cecal microbiome were profiled to gain a better understanding of primary differences in these lines. the percent of splenic cd4(+) t cells were similar regardless of mdv challenge status in both bird lines. in contrast, cd8αα profiles were different ... | 2016 | 27604255 |
| field studies of the detection, persistence and spread of the rispens cvi988 vaccine virus and the extent of co-infection with marek's disease virus. | to use specific real-time qpcr to determine (1) the vaccination success of rispens cvi988 vaccine in feathers and dust; (2) persistence of rispens infection in vaccinated layer chickens; (3) extent of co-infection with wild-type marek's disease virus (mdv) in vaccinated layers; and (4) presence of rispens virus in unvaccinated broiler flocks. | 2016 | 27569836 |
| validation of alternative transcript splicing in chicken lines that differ in genetic resistance to marek's disease. | utilizing rna-seq data, 1,574 candidate genes with alternative splicing were previously identified between two chicken lines that differ in marek's disease (md) genetic resistance under control and marek's disease virus infection conditions. after filtering out 1,530 genes with splice variants in the first or last exon, 44 genes were screened for possible exon loss or gain using pcr and gel electrophoresis. consequently, 7 genes exhibited visually detectable differential expression of splice var ... | 2016 | 27565867 |
| evaluation and validation of reference gene stability during marek's disease virus (mdv) infection. | quantitative rt-pcr (qrt-pcr) is widely used in the study of relative gene expression in general, and has been used in the field of marek's disease (md) research to measure transcriptional responses to infection and/or vaccination. studies in the past have either employed cellular β-actin (bact) or glyceraldehyde-3-phosphate dehydrogenase (gapdh) as internal reference genes, although the stability of their expression in the context of marek's disease virus (mdv) infection has never been investig ... | 2016 | 27448823 |
| diversity of meq gene from clinical marek's disease virus infection in saudi arabia. | the aim of this study was to demonstrate the genomic features of meq gene of marek's disease virus (mdv) recently circulating in saudi arabia (sa). | 2016 | 27397979 |
| combination of two marek's disease virus vectors shows effective vaccination against marek's disease, infectious bursal disease, and newcastle disease. | herpesvirus of turkeys (hvt) is a widely used vector for poultry vaccines. however, different hvts expressing different foreign antigens cannot always be used simultaneously because of the risk of recombination and interference. in this study, we inoculated a mixture of an hvt-expressing the antigen of newcastle disease virus (ndv; hvt/nd) and marek's disease virus (mdv) serotype 1 rispens virus expressing the antigen of infectious bursal disease virus (ibd; ripens/ibd) into chickens. this mixtu ... | 2016 | 27309290 |
| severe necrotic dermatitis in the combs of line 63 chickens infected with marek's disease virus. | marek's disease virus (mdv), the aetiological agent of mareks' disease (md), is a highly cell-associated oncogenic α-herpesvirus that replicates in chicken lymphocytes and establishes a latent infection within cd4(+) t cells. we investigated the possible effect of mdv infection on the exacerbation of necrotic dermatitis in the combs of md-susceptible (72) and md-resistant (63) chicken lines at 21 days post infection. mdv-infected birds of line 63 are relatively resistant to tumour development bu ... | 2016 | 27215315 |
| transcriptional and bioinformatic analysis provide a relationship between host response changes to marek's disease viruses infection and an integrated long terminal repeat. | gx0101, marek's disease virus (mdv) strain with a long terminal repeat (ltr) insert of reticuloendotheliosis virus (rev), was isolated from cvi988/rispens vaccinated birds showing tumors. we have constructed a ltr deleted strain gx0101δltr in our previous study. to compare the host responses to gx0101 and gx0101δltr, chicken embryo fibroblasts (cef) cells were infected with two mdv strains and a gene-chip containing chicken genome was employed to examine gene transcription changes in host cells ... | 2016 | 27200301 |
| genetic evolution of gallid herpesvirus 2 isolated in china. | gallid herpesvirus 2 (gahv-2), which causes marek's disease in chickens and has caused extensive economic losses, has recently evolved increased virulence in china. to better understand the genetic basis of the pathogenic characteristics changed and increased virulence, we sequenced the genomes of six new gahv-2 strains (lcc, lts, wc/1203, jl/1404, cc/1409, and hs/1412) isolated from chickens with failed immunisation as well as one previously isolated chinese gahv-2 strain, j-1. based on a multi ... | 2016 | 27112385 |
| real-time pcr for differential quantification of cvi988 vaccine virus and virulent strains of marek's disease virus. | cvi988/rispens vaccine, the 'gold standard' vaccine against marek's disease in poultry, is not easily distinguishable from virulent strains of marek's disease herpesvirus (mdv). accurate differential measurement of cvi988 and virulent mdv is commercially important to confirm successful vaccination, to diagnose marek's disease, and to investigate causes of vaccine failure. a real-time quantitative pcr assay to distinguish cvi988 and virulent mdv based on a consistent single nucleotide polymorphis ... | 2016 | 26973285 |
| deletion of the bac sequences from recombinant meq-null marek's disease (md) virus increases immunosuppression while maintaining protective efficacy against md. | marek's disease virus (mdv) gx0101 is a field strain of mdv with a naturally occurring insertion of the reticuloendotheliosis virus (rev) long terminal repeat (ltr) fragment. both copies of the meq gene were knocked out in the gx0101 bacterial artificial chromosome (bac) clone to construct the recombinant virus sc9-1, resulting in a complete lack of pathogenicity and providing better protection against md than cvi988/rispens. in the present study, the bac sequences in sc9-1 were removed using a ... | 2016 | 26957626 |
| effects of rispens cvi988 vaccination followed by challenge with marek's disease viruses of differing virulence on the replication kinetics and shedding of the vaccine and challenge viruses. | vaccination with "imperfect" vaccines that prevent disease but not infection is strongly implicated in the observed increased virulence of marek's disease virus (mdv) over the past six decades. the current "gold standard" vaccine, rispens cvi988 (rispens), has maintained efficacy despite use for five decades, raising the question of whether it too favours higher virulence mdvs. to investigate this, we studied the kinetics of rispens cvi988 (rispens) and two mdv strains of different virulence in ... | 2016 | 26790931 |
| virus and host genomic, molecular, and cellular interactions during marek's disease pathogenesis and oncogenesis. | marek's disease virus (mdv) is a chicken alphaherpesvirus that causes paralysis, chronic wasting, blindness, and fatal lymphoma development in infected, susceptible host birds. this disease and its protective vaccines are highly relevant research targets, given their enormous impact within the poultry industry. further, marek's disease (md) serves as a valuable model for the investigation of oncogenic viruses and herpesvirus patterns of viral latency and persistence--as pertinent to human health ... | 2016 | 26755654 |
| keratinocytes derived from chicken embryonic stem cells support marek's disease virus infection: a highly differentiated cell model to study viral replication and morphogenesis. | marek's disease is a virus disease with worldwide distribution that causes major losses to poultry production. vaccines against marek's disease virus, an oncogenic alphaherpesvirus, reduce tumour formation but have no effect on virus shedding. successful horizontal virus transmission is linked to the active viral replication in feather follicle epithelial cells of infected chickens, from which infectious viral particles are shed into the environment. the feather follicle epithelium is the sole t ... | 2016 | 26742789 |
| marek's disease virus undergoes complete morphogenesis after reactivation in a t-lymphoblastoid cell line transformed by recombinant fluorescent marker virus. | t-lymphocytes are central targets of marek's disease, a major chicken disease induced by the oncogenic alphaherpesvirus marek's disease virus (mdv). t-lymphocyte infection is also associated with immunosuppression and virus latency. to decipher viral morphogenesis in t-lymphocytes, we used the recombinant vrb-1b 47egfp marker virus to generate a new lymphoblastoid cell line, 3867k, that exhibited typical properties of other mdv-transformed chicken cell lines in term of cell markers, reactivation ... | 2016 | 26612074 |
| molecular and pathogenicity characterization of gallid herpesvirus 2 newly isolated in china from 2009 to 2013. | during the course of our continuous surveillance of gallid herpesvirus 2 (gahv-2), 44 isolates were obtained from gahv-2-positive chickens of different flocks in china from 2009 to 2013. the meq gene, considered as a major gahv-2 oncogene, was sequenced and was found to contain an open reading frame of 1020 nucleotides encoding a 339 amino acid (aa) polypeptide in all isolates. compared with the gahv-2 ga strain, the meq genes in 15.9 % (7/44) of the isolates analyzed in this study contained an ... | 2016 | 26611441 |
| activation of toll-like receptor 3 inhibits marek's disease virus infection in chicken embryo fibroblast cells. | toll-like receptor 3 (tlr3) is a critical component of the innate immune system against viral infection and controls the activation of adaptive immunity. the role of tlr3 in marek's disease virus (mdv) infection is not clear. in this study, we found that the abundance of tlr3 mrna was significantly higher in chicken embryo fibroblast cells (cef) infected with mdv than in a control group. activated tlr3 signaling via tlr3 ligand stimulation inhibited replication of the rb1b strain of mdv in cef c ... | 2016 | 26597188 |
| development, characterization and optimization of a new suspension chicken-induced pluripotent cell line for the production of newcastle disease vaccine. | traditionally, substrates for production of viral poultry vaccines have been embryonated eggs or adherent primary cell cultures. the difficulties and cost involved in scaling up these substrates in cases of increased demand have been a limitation for vaccine production. here, we assess the ability of a newly developed chicken-induced pluripotent cell line, ba3, to support replication and growth of newcastle disease virus (ndv) lasota vaccine strain. the characteristics and growth profile of the ... | 2016 | 26586283 |