| 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 |
| protection provided by rispens cvi988 vaccine against marek's disease virus isolates of different pathotypes and early prediction of vaccine take and md outcome. | we tested the level of protection provided by the rispens cvi988 (rispens) vaccine against challenge with a virulent marek's disease virus (mdv) pathotype (vmdv) and a very virulent pathotype (vvmdv) and the accuracy of a range of predictive measures of marek's disease (md) incidence and vaccine take. commercial layer chicks (n = 236) were vaccinated (or not) with 4000 plaque-forming units (pfu) of rispens vaccine at hatch and challenged (or not) with 500 pfu of each challenge virus five days po ... | 2016 | 26503904 |
| chicken gga-mir-181a targets mybl1 and shows an inhibitory effect on proliferation of marek's disease virus-transformed lymphoid cell line. | marek's disease (md), caused by marek's disease virus (mdv), is a lymphoproliferative neoplastic disease of chickens and is characterized by md lymphoma in multiple visceral organs of chicken. it causes great damage to poultry health. recently, mirna has been reported to be involved in marek's disease lymphomagenesis. our previous study showed that gga-mir-181a was downregulated in mdv-induced lymphoma, and its target gene, v-myb myeloblastosis viral oncogene homolog-like 1 (mybl1), was predicte ... | 2015 | 26500265 |
| fine mapping of qtl and genomic prediction using allele-specific expression snps demonstrates that the complex trait of genetic resistance to marek's disease is predominantly determined by transcriptional regulation. | marek's disease (md) is a lymphoproliferative disease of poultry induced by marek's disease virus (mdv), a highly oncogenic alphaherpesvirus. identifying the underlying genes conferring md genetic resistance is desired for more efficacious control measures including genomic selection, which requires accurately identified genetic markers throughout the chicken genome. | 2015 | 26481588 |
| evaluation of factors influencing efficacy of vaccine strain cvi988 against marek's disease in meat-type chickens. | marek's disease (md) strain cvi988 is the most-protective commercially available vaccine against very virulent plus (vv+) marek's disease virus (mdv). however, its use in meat-type chickens has been controversial. while several countries have been using cvi988 for more than 40 yr, others do not authorize its use or it is restricted mainly to layers. the use of cvi988 in meat-type chickens will be necessary in the future in areas where other vaccine protocols fail. the objective of this study was ... | 2015 | 26478159 |
| immune responses in cecal tonsils of marek's disease virus-infected chickens. | marek's disease (md) is a lymphoproliferative disease of domestic chickens that is caused by a highly cell-associated oncogenic α-herpesvirus, marek's disease virus (mdv). mdv replicates in chicken lymphocytes and establishes a latent infection within cd4+ t cells. clinical signs of md include depression, crippling, weight loss, bursal/thymic atrophy, neurologic disorders, and rapid onset of t cell lymphomas that infiltrate lymphoid tissues, visceral organs, and peripheral nerves. the cecal tons ... | 2015 | 26473671 |
| the conservation and signatures of lincrnas in marek's disease of chicken. | long intergenic non-coding rnas (lincrnas) associated with a number of cancers and other diseases have been identified in mammals, but they are still formidable to be comprehensively identified and characterized. marek's disease (md) is a t cell lymphoma of chickens induced by marek's disease virus (mdv). here, we used a md chicken model to develop a precise pipeline for identifying lincrnas and to determine the roles of lincrnas in t cell tumorigenesis. more than 1,000 lincrna loci were identif ... | 2015 | 26471251 |
| growth inhibitive effect of betulinic acid combined with tripterine on msb-1 cells and its mechanism. | marek's disease (md), a highly infectious lymphoproliferative disease in chickens, is caused by a cell-associated oncogenic herpesvirus, marek's disease virus (mdv). msb-1 is a md-derived lymphoblastoid cell line and can induce tumors when inoculated into susceptible chickens. betulinic acid, which is present as one of the major effective components in many traditional chinese medicines, has recently been reported to inhibit growth of cancer cells and employed as a potential anticancer agent. tr ... | 2015 | 26467010 |
| cytokine gene expression in lung mononuclear cells of chickens vaccinated with herpesvirus of turkeys and infected with marek's disease virus. | marek's disease virus (mdv) enters the chicken host through the respiratory system. however, little is known about the host immune responses induced by mdv in the lungs. to characterize these responses, chickens were vaccinated with herpesvirus of turkeys (hvt) and challenged with the rb1b strain of mdv via the respiratory route. lung mononuclear cells of vaccinated only, challenged only, vaccinated and challenged, as well as age-matched controls were isolated at 4, 10, and 21 days post-infectio ... | 2015 | 26447971 |
| sodium tanshinone iia sulfonate affects marek's disease virus replication by inhibiting gb expression. | previous studies demonstrated that sodium tanshinone iia sulfonate (sts) could inhibit mdv replication in vitro. the mechanism about how sts inhibits mdv replication is still not well understood. | 2016 | 26428057 |
| observation of risk factors, clinical manifestations and genetic characterization of recent newcastle disease virus outbreak in west malaysia. | newcastle disease virus remains a constant threat in commercial poultry farms despite intensive vaccination programs. outbreaks attributed to nd can escalate and spread across farms and states contributing to major economic loss in poultry farms. | 2015 | 26293577 |
| the influence of major histocompatibility complex and vaccination with turkey herpesvirus on marek's disease virus evolution. | over the last five decades, the pathogenicity of the marek's disease virus (mdv) has evolved from the relatively mild strains (mmdv) observed in the 1960s to the more severe very-virulent-plus strains currently observed in today's outbreaks. the use of vaccines to control marek's disease (md), but not the infection cycle, is thought to be the major influence on the evolution of mdv. selection for genetic resistance to md has also been employed by the industry to control md in the commercial sett ... | 2015 | 26292545 |
| the mut ul5-i682r marek's disease virus with a single nucleotide mutation within the helicase-primase subunit gene not only reduces virulence but also provides partial vaccinal protection against marek's disease. | marek's disease virus (mdv) is an oncogenic herpesvirus that afflicts chickens with the disease known as marek's disease (md). this virus induces tumors, nerve lesions, immunosuppression, and death of affected birds. vaccines are the primary control method for md but, due to the periodic evolution of field strains, it is necessary to explore the development of new md vaccines. md vaccines are often attenuated mdv strains generated through serial passage in vitro. we previously used experimental ... | 2015 | 26292541 |
| downregulation of cellular prion protein inhibited the proliferation and invasion and induced apoptosis of marek's disease virus-transformed avian t cells. | cellular prion protein (prp(c)) is ubiquitously expressed in the cytomembrane of a considerable number of eukaryotic cells. although several studies have investigated the functions of prp(c) in cell proliferation, cell apoptosis, and tumorigenesis of mammals, the correlated functions of chicken prp(c) (chprp(c)) remain unknown. in this study, stable chprp(c)-downregulated marek's disease (md) virus-transformed avian t cells (msb1-sirna-3) were established by introducing short interfering rna (si ... | 2016 | 26243599 |
| imperfect vaccination can enhance the transmission of highly virulent pathogens. | could some vaccines drive the evolution of more virulent pathogens? conventional wisdom is that natural selection will remove highly lethal pathogens if host death greatly reduces transmission. vaccines that keep hosts alive but still allow transmission could thus allow very virulent strains to circulate in a population. here we show experimentally that immunization of chickens against marek's disease virus enhances the fitness of more virulent strains, making it possible for hyperpathogenic str ... | 2015 | 26214839 |
| outbreak of marek's disease in a vaccinated broiler breeding flock during its peak egg-laying period in china. | outbreaks of marek's disease (md), caused by marek's disease virus (mdv), primarily occur in 10-12-week-old hens. | 2015 | 26202662 |
| genomic deletions and mutations resulting in the loss of eight genes reduce the in vivo replication capacity of meleagrid herpesvirus 1. | meleagrid herpesvirus 1 (mehv-1 or turkey herpesvirus) has been widely used as a vaccine in commercial poultry. initially, these vaccine applications were for the prevention of marek's disease resulting from gallid herpesvirus 2 infections, while more recently mehv-1 has been used as recombinant vector for other poultry infections. the construction of herpesvirus infectious clones that permit propagation and manipulation of the viral genome in bacterial hosts has advanced the studies of herpesvi ... | 2015 | 26149791 |
| differential expression of marek's disease virus (mdv) late proteins during in vitro and in situ replication: role for pul47 in regulation of the mdv ul46-ul49 gene locus. | marek's disease virus (mdv) is a lymphotropic alphaherpesvirus that replicates in a highly cell-associated manner in vitro. production of infectious cell-free virus only occurs in feather follicle epithelial (ffe) cells of infected chicken skins. previously, we described differential expression for a core alphaherpesvirus protein, pul47 that was found to be abundantly expressed in ffe cells of infected chickens, while barely detectable during in vitro propagation. here, we further examined the d ... | 2015 | 26117307 |
| in vivo characterisation of two australian isolates of marek's disease virus including pathology, viral load and neuropathotyping based on clinical signs. | to evaluate the pathogenicity of australian marek's disease virus (mdv) isolate mpf23 (1985) against the reference strain mpf57 based on pathology, viral load and neuropathotyping on the basis of clinical signs. | 2015 | 26113349 |
| the inhibitory effects of gga-mir-199-3p, gga-mir-140-3p, and gga-mir-221-5p in marek's disease tumorigenesis. | marek's disease (md) is lymphoproliferative neoplastic disease in chickens, which is caused by marek's disease virus (mdv). our previous study profiled microrna (mirna) transcriptome in md lymphoma, and found that gga-mir-199-3p, gga-mir-140-3p, and gga-mir-221-5p were down-regulated in md lymphoma. in this study, we further investigated their differential expression between mdv-infected spleens and noninfected spleens at 4, 7, 14, 21, and 28 d postinfection (dpi) to elucidate whether deregulati ... | 2015 | 26112035 |
| marek's disease: genetic regulation of gallid herpesvirus 2 infection and latency. | gallid herpesvirus-2 (gahv-2) is an oncogenic α-herpesvirus that causes marek's disease (md), a t cell lymphosarcoma (lymphoma) of domestic fowl (chickens). the gahv-2 genome integrates by homologous recombination into the host genome and, by modulating expression of viral and cellular genes, induces transformation of latently infected cells. md is a unique model of viral oncogenesis. mechanisms implicated in the regulation of viral and cellular genes during gahv-2 infection operate at transcrip ... | 2015 | 26067852 |
| in vitro model for lytic replication, latency, and transformation of an oncogenic alphaherpesvirus. | marek's disease virus (mdv) is an alphaherpesvirus that causes deadly t-cell lymphomas in chickens and serves as a natural small animal model for virus-induced tumor formation. in vivo, mdv lytically replicates in b cells that transfer the virus to t cells in which the virus establishes latency. mdv also malignantly transforms cd4+ t cells with a t(reg) signature, ultimately resulting in deadly lymphomas. no in vitro infection system for primary target cells of mdv has been available due to the ... | 2015 | 26039998 |
| experimental pathological studies of an indian chicken anaemia virus isolate and its detection by pcr and fat. | chicken infectious anaemia virus (ciav) is one of the potent immunosuppressive and economically important agents affecting poultry industry worldwide. recent reports indicate the emergence of this virus in the poultry flocks of the country. the present study aimed to investigate the pathogenic potential of a recent isolate of ciav obtained from poultry flock of uttaranchal state, india. twenty first day-old age specific pathogen free (spf) chicks were inoculated intramuscularly with 10(4.5) medi ... | 2014 | 26035953 |
| marek's disease virus associated ocular lymphoma in roulroul partridges (rollulus rouloul). | two 1-year old roulroul partridges (rollulus rouloul), one male and one female, were presented because of eye problems and anorexia. twenty of the 30 roulroul partridges in the owner's collection had already died. the affected birds stopped eating, became thinner, and eventually died. antibiotic treatment, which started because of the suspicion of a septicaemic process, was unsuccessful. at clinical examination of the two partridges it was found that in both birds, one eye ball was filled with a ... | 2015 | 26021782 |
| addition of a ul5 helicase-primase subunit point mutation eliminates bursal-thymic atrophy of marek's disease virus ∆meq recombinant virus but reduces vaccinal protection. | marek's disease virus (mdv) is an oncogenic alphaherpesvirus and the causative agent of marek's disease (md), characterized by immunosuppression, paralysis, nerve enlargement and induction of t-cell lymphomas in chickens. despite widespread usage of vaccines since the 1970s to control md, more virulent field strains of mdv have emerged that overcome vaccinal protection, necessitating the development of new and more protective md vaccines. the ∆meq virus, a recombinant md5 strain mdv lacking the ... | 2015 | 25968878 |
| detection of specific ul49 sequences of marek's disease virus cvi988/rispens strain using loop-mediated isothermal amplification. | marek's disease (md) is a tumoral disease of chickens that can be controlled by vaccines based on non-pathogenic strains of turkey herpesvirus (hvt), sb-1 strain belonging to serotype 2, or the attenuated cvi988/rispens strain belonging to serotype 1 of marek's disease virus (mdv). currently, the 'gold standard' in md prophylaxis is the rispens strain-based vaccine which protects against very virulent mdv and disease onset. previous studies have shown that loop-mediated isothermal amplification ... | 2015 | 25920566 |
| histone modifications induced by mdv infection at early cytolytic and latency phases. | marek's disease (md) is a highly contagious, lymphomatous disease of chickens induced by a herpesvirus, marek's disease virus (mdv) that is the cause of major annual losses to the poultry industry. md pathogenesis involves multiple stages including an early cytolytic phase and latency, and transitions between these stages are governed by several host and environmental factors. the success of vaccination strategies has led to the increased virulence of mdv and selective breeding of naturally resi ... | 2015 | 25896894 |
| expression levels of mhc class i molecules are inversely correlated with promiscuity of peptide binding. | highly polymorphic major histocompatibility complex (mhc) molecules are at the heart of adaptive immune responses, playing crucial roles in many kinds of disease and in vaccination. we report that breadth of peptide presentation and level of cell surface expression of class i molecules are inversely correlated in both chickens and humans. this relationship correlates with protective responses against infectious pathogens including marek's disease virus leading to lethal tumours in chickens and h ... | 2015 | 25860507 |
| isolation and full-genome sequence of two reticuloendotheliosis virus strains from mixed infections with marek's disease virus in china. | reticuloendotheliosis virus (rev), classified as a gammaretrovirus, has a variety of hosts, including chickens, ducks, geese, turkeys, and wild birds. rev causes a series of pathological syndromes, especially the immunosuppression of the host, which may lead to an increased susceptibility to other pathogens, thus greatly damaging the poultry industry. mixed infections of rev and marek's disease virus (mdv) have been reported in many countries, including china. previous reports revealed that mdv ... | 2015 | 25850423 |
| temporal expression and dna hypomethylation profile of cd30 in marek's disease virus-infected chicken spleens. | marek's disease (md) is a viral neoplastic disease of chickens caused by marek's disease virus (mdv), which is serious threat to worldwide poultry industry. our previous studies showed that the cd30 gene was hypomethylated in md lymphoma. in this study, we further analyzed differential expression patterns and methylation levels of the cd30 gene between mdv-infected and noninfected spleens at 4, 7, 14, 21, and 28 d postinfection (dpi). the results showed that the expression of cd30 in mdv-infecte ... | 2015 | 25840961 |
| absolute quantification of a very virulent marek's disease virus dynamic quantity and distributions in different tissues. | chickens infected with marek's disease virus (mdv) carry the virus consistently for a long time, which increases the incidence and rate of virus-induced multi-organ tumors and increases its potential for horizontal transmission. there is a positive correlation between very virulent (vv) mdv quantity and the pathology. the purpose of this study was to determine the vvmdv loads dynamics in different phases, and the correlation between the viral quantity and tumor development. we used a sybr green ... | 2015 | 25834249 |
| characterizing in vivo stability and potential interactions of a ul5 helicase-primase mutation previously shown to reduce virulence and in vivo replication of marek's disease virus. | the unpredictable yet recurrent emergence of more virulent field strains of marek's disease virus (mdv) in marek's disease (md) vaccinated flocks of chickens has prompted concerns regarding the sustainability of md vaccines. a single non-synonymous point mutation (i682r) within the ul5 helicase-primase unit was shown to reduce virulence by over 90%. considering in vitro attenuation is commonly used to generate md vaccines, this result prompted further characterization of this mutation, particula ... | 2015 | 25828576 |
| pathogenic characteristics of marek's disease virus field strains prevalent in china and the effectiveness of existing vaccines against them. | the virulence of marek's disease virus (mdv) is continuously evolving, and more virulent mdv pathotypes are emerging, thereby reducing the effectiveness of the existing vaccines. in this study, feather pulps were collected from diseased chickens in commercial chicken flocks in china that presented significant md visceral tumors in 2011 and were inoculated into a monolayer of duck embryo fibroblasts (defs). three field isolates of mdv were obtained by plaque cloning and identified as mdv via pcr ... | 2015 | 25770895 |
| [comparison of immunoprotection between vaccination with meq-deleted marek's disease virus and vaccine strain cvi988/rispens]. | to evaluate and compare the immunoprotection between a meq-deleted marek's disease virus (mdv) and cvi988/rispens against mdv very virulent strain gx0101. | 2014 | 25752142 |
| expression of fluorescent proteins within the repeat long region of the marek's disease virus genome allows direct identification of infected cells while retaining full pathogenicity. | marek's disease virus (mdv) is a lymphotropic alphaherpesvirus and causes marek's disease (md) in chickens. rlorf4 is an mdv-specific gene located in the repeat long (rl) regions of the genome and is directly involved in attenuation. in this report, we generated recombinant (r)mdvs in which egfp or mrfp was inserted in-frame of the 3' end of the rlorf4 gene. in vitro growth was unaffected and infected cells could be identified by using fluorescent microscopy. interestingly, though inserted in-fr ... | 2015 | 25725150 |
| isolation, identification, and whole genome sequencing of reticuloendotheliosis virus from a vaccine against marek's disease. | according to the requirements of the ministry of agriculture of china, all vaccines must be screened for exogenous virus contamination before commercialization. a freeze-dried vaccine against marek's disease was used to inoculate specific pathogen-free chickens, from which serum samples were collected after 42 days. the results were positive for reticuloendotheliosis virus antibody, which was indicative of reticuloendotheliosis virus contamination. after neutralization with serum positive for ma ... | 2015 | 25725074 |
| transcriptional analysis of host responses to marek's disease virus infection in chicken thymus. | marek's disease virus (mdv) is a cell-associated alpha-herpesvirus that causes t-cell lymphomas and nervous disorders in chickens. different from other lymphoid organs, the thymus is the site of t-cell maturation and differentiation. however, the transcriptional response to mdv infection in the chicken thymus is still not known. in this study, we performed genome-wide expression analysis in thymus tissues of rb1b-infected chickens at different time points to investigate the molecular mechanisms ... | 2015 | 25677615 |
| in vivo expression patterns of micrornas of gallid herpesvirus 2 (gahv-2) during the virus life cycle and development of marek's disease lymphomas. | in the past decade, a large number of micrornas (mirnas) have been identified in the viral genome of gallid herpesvirus 2 (gahv-2), which is historically known as marek's disease virus type 1. the biological role of most gahv-2 mirnas remains unclear. in the present study, we have performed an overall gene expression profile of gahv-2 mirnas during the virus life cycle at each phase of the developing disease, a highly contagious, lymphoproliferative disorder, and neoplastic immunosuppressive dis ... | 2015 | 25666057 |
| common occurrence of gallid herpesvirus-2 with reticuloendotheliosis virus in chickens caused by possible contamination of vaccine stocks. | the aim of this study was to investigate the common occurrence of reticuloendotheliosis virus (rev) among gallid herpesvirus 2 (gahv-2) infected chickens. the possible cause of this co-occurrence may be linked to contaminated vaccine stocks, which were also examined. | 2015 | 25641090 |
| molecular evolution of marek's disease virus (mdv) field strains in a 40-year time period. | marek's disease (md) presents a serious threat in poultry production. the disease has been limited for over 40 yr by protective vaccination. the widely applied vaccination against md is also one of the factors causing evolutionary pressure onto field marek's disease virus (mdv) virulent strains. molecular evolution of mdv genes involved in oncogenesis may increase the pathogenicity of mdv virulent strains. the goal of the presented study was to sum up the molecular evolution of mdv field strains ... | 2014 | 25618999 |
| a recombinant field strain of marek's disease (md) virus with reticuloendotheliosis virus long terminal repeat insert lacking the meq gene as a vaccine against md. | marek's disease virus (mdv) gx0101, which is a field strain with a naturally occurring insertion of the reticuloendotheliosis virus (rev) long terminal repeat (ltr) fragment, shows distinct biological activities. deletion of the meq gene in gx0101 contributes to its complete loss of pathogenicity and oncogenicity in spf chickens, but this virus has a kanamycin resistance gene (kan(r)) residual at the site of meq gene. in the present study, the kan(r) was knocked out and a meq-null virus with a g ... | 2015 | 25562789 |
| marek's disease virus-encoded analog of microrna-155 activates the oncogene c-myc by targeting ltbp1 and suppressing the tgf-β signaling pathway. | marek's disease virus (mdv) is a representative alpha herpes virus able to induce rapid-onset t-cell lymphoma in its natural host and regarded as an ideal model for the study of virus-induced tumorigenesis. recent studies have shown that the mdv1-mir-m4-5p, a viral analog of cellular mir-155, is critical for mdv׳s oncogenicity. however, the precise mechanism whereby it was involved in md lymphomagenesis remained unknown. we have presently identified the host mrna targets of mdv1-mir-m4-5 and ide ... | 2015 | 25528440 |
| poly(a) binding protein 1 enhances cap-independent translation initiation of neurovirulence factor from avian herpesvirus. | poly(a) binding protein 1 (pabp1) plays a central role in mrna translation and stability and is a target by many viruses in diverse manners. we report a novel viral translational control strategy involving the recruitment of pabp1 to the 5' leader internal ribosome entry site (5l ires) of an immediate-early (ie) bicistronic mrna that encodes the neurovirulence protein (pp14) from the avian herpesvirus marek's disease virus serotype 1 (mdv1). we provide evidence for the interaction between an int ... | 2014 | 25503397 |
| the significance of the individual meq-clustered mirnas of marek's disease virus in oncogenesis. | marek's disease virus (mdv) is an important oncogenic alphaherpesvirus that induces rapid-onset t-cell lymphomas in its natural hosts. the meq-clustered mirnas encoded by mdv have been suggested to play potentially critical roles in the induction of lymphomas. using the technique of bacterial artificial chromosome mutagenesis, we have presently constructed a series of specific mirna-deleted mutants and demonstrate that these mirnas are not essential for replication of mdv and have no effects on ... | 2015 | 25502647 |
| temporal kinetics of marek's disease herpesvirus: integration occurs early after infection in both b and t cells. | marek's disease virus (mdv) is an oncogenic α-herpesvirus that induces marek's disease characterized by fatal lymphomas in chickens. here, we explored the timing during pathogenesis when the virus integrates into the host genome, the cell type involved, the role of viral integration on cellular transformation, and tumor clonality. three immune organs of chicken (thymus, bursa, and spleen) were extracted following infection with either an oncogenic or a non-oncogenic strain of mdv. using molecula ... | 2014 | 25402709 |
| the orf012 gene of marek's disease virus type 1 produces a spliced transcript and encodes a novel nuclear phosphoprotein essential for virus growth. | marek's disease virus (mdv), an alphaherpesvirus, is the causative agent of a lethal disease in chickens characterized by generalized nerve inflammation and rapid lymphoma development. the extensive colinearity of the mdv genome with those of related herpesviruses has eased functional characterization of many mdv genes. however, mdv carries a number of unique open reading frames (orfs) that have not yet been investigated regarding their coding potentials and the functions of their products. amon ... | 2015 | 25392220 |
| herpesvirus genome integration into telomeric repeats of host cell chromosomes. | it is well known that numerous viruses integrate their genetic material into host cell chromosomes. human herpesvirus 6 (hhv-6) and oncogenic marek's disease virus (mdv) have been shown to integrate their genomes into host telomeres of latently infected cells. this is unusual for herpesviruses as most maintain their genomes as circular episomes during the quiescent stage of infection. the genomic dna of hhv-6, mdv, and several other herpesviruses harbors telomeric repeats (tmrs) that are identic ... | 2014 | 26958721 |
| vaccine and oncogenic strains of gallid herpesvirus 2 contain specific subtype variations in the 5' region of the latency-associated transcript that evolve in vitro and in vivo. | gallid herpesvirus 2 (gahv-2) is the alphaherpesvirus responsible for marek's disease (md), a t-cell lymphoma of chickens. the virulence of the gahv-2 field strain is steadily increasing, but md is still controlled by the cvi988/rispens vaccine. we tried to determine distinguishing traits of the cvi988/rispens vaccine by focusing on the 5' end region of the latency-associated transcript (5'lat). it includes a variable number of 60-bp tandem repeats depending on the gahv-2 strain. by analyzing si ... | 2015 | 25298182 |
| role of the short telomeric repeat region in marek's disease virus replication, genomic integration, and lymphomagenesis. | marek's disease virus (mdv) is a cell-associated alphaherpesvirus that causes generalized polyneuritis and t-cell lymphomas in chickens. mdv is able to integrate its genome into host telomeres, but the mechanism of integration is poorly understood. the mdv genome harbors two arrays of telomeric repeats (tmr) at the ends of its linear genome: multiple telomeric repeats (mtmr), with a variable number of up to 100 repeats, and short telomeric repeats (stmr), with a fixed number of 6 repeats. the mt ... | 2014 | 25275118 |
| [isolation and characterization of a non-pathogenic marek's disease virus with a naturally inserted rev ltr sequence]. | marek's disease virus (mdv), gd06 strain, was isolated from healthy three-yellow chickens without md vaccine. in this study, we characterized gd06 strain. | 2014 | 25272816 |
| genetic variation within the mx gene of commercially selected chicken lines reveals multiple haplotypes, recombination and a protein under selection pressure. | the mx protein is one of the best-characterized interferon-stimulated antiviral mediators. mx homologs have been identified in most vertebrates examined; however, their location within the cell, their level of activity, and the viruses they inhibit vary widely. recent studies have demonstrated multiple mx alleles in chickens and some reports have suggested a specific variant (s631n) within exon 14 confers antiviral activity. in the current study, the complete genome of nine elite egg-layer type ... | 2014 | 25244433 |
| replication kinetics and shedding of very virulent marek's disease virus and vaccinal rispens/cvi988 virus during single and mixed infections varying in order and interval between infections. | vaccination is thought to contribute to an evolution in virulence of the marek's disease virus (mdv) as vaccines prevent disease but not infection. we investigated the effects of co-infections at various intervals between rispens/cvi988 vaccine virus (rispens) and very virulent mdv (vvmdv) on the replication and shedding of each virus. the experiment used 600 isa brown layer chickens in 24 isolators with all treatments replicated in two isolators. chickens were vaccinated with rispens and/or cha ... | 2014 | 25213229 |
| efficient marek's disease virus (mdv) and herpesvirus of turkey infection of the qm7 cell line that does not contain latent mdv genome. | marek's disease virus (mdv; also known as gallid herpesvirus 2, mdv-1) causes oncogenic disease in chickens producing clinical signs that include lymphomas, visceral tumours, nerve lesions, and immunosuppression. mdv vaccines are widely used and mostly produced using primary cells: chicken embryo fibroblast cells, duck embryo fibroblast cells, chicken embryo kidney cells or chicken kidney cells. an immortalized cell line that can be used to manufacture the virus has long been desired. in this re ... | 2014 | 25204414 |
| the relationship between the alternative exon 7 splice variant of the bf gene and mhc-related marek's disease resistance in chickens. | the study was to analyse the relationship between the alternative exon 7 splice variant of the bf gene and mhc-related marek's disease (md) resistance in chickens. the experiment first determined whether or not the cocks of xiayan chickens have alternative splicing-out of the exon 7 of the bf gene from peripheral blood leucocytes (pbls). then, selected two groups: group k included the offspring of the selected cocks which have no alternative splicing-out of the exon 7 of the bf gene; group y inc ... | 2014 | 25124506 |
| marek's disease virus influences the core gut microbiome of the chicken during the early and late phases of viral replication. | marek's disease (md) is an important neoplastic disease of chickens caused by the marek's disease virus (mdv), an oncogenic alphaherpesvirus. in this study, dysbiosis induced by mdv on the core gut flora of chicken was assessed using next generation sequence (ngs) analysis. total fecal and cecum-derived samples from individual birds were used to estimate the influence of mdv infection on the gut microbiome of chicken. our analysis shows that mdv infection alters the core gut flora in the total f ... | 2014 | 25065611 |
| correlation between marek's disease virus pathotype and replication. | marek's disease (md) virus (mdv) is an alphaherpesvirus that causes md, a lymphoproliferative disease in chickens. pathotyping has become an increasingly important assay for monitoring shifts in virulence of field strains; however, it is time-consuming and expensive, and alternatives are needed to provide fast answers in the face of current outbreaks. the purpose of this study was to determine whether differences in virus replication between pathotypes that have been reported using a small numbe ... | 2014 | 25055634 |
| marek's disease virus-induced transient cecal tonsil atrophy. | marek's disease (md) is a lymphoproliferative disease of domestic chickens that is caused by a highly cell-associated oncogenic alpha-herpesvirus, marek's disease virus (mdv). mdv replicates in chicken lymphocytes and establishes a latent infection within cd4+ t cells. md is characterized by bursal and thymic atrophy and rapid onset of t cell lymphomas that infiltrate lymphoid tissues, visceral organs, and peripheral nerves with severe clinical symptoms that include transient paralysis, anemia, ... | 2014 | 25055631 |
| detection and differentiation of cvi988 (rispens vaccine) from other serotype 1 marek's disease viruses. | the serotype 1 marek's disease virus (mdv) is the causative agent for marek's disease (md), a lymphoproliferative disease of chickens of great concern to the poultry industry. cvi988 (rispens vaccine), an attenuated serotype 1 mdv, is currently the most efficacious commercially available vaccine for preventing md. however, it is difficult to detect and differentiate cvi988 when other serotype 1 mdvs are present. to facilitate the detection of cvi988, we developed two sets of primers for a mismat ... | 2014 | 25055627 |
| transcriptional activity comparison of different sites in recombinant marek's disease virus for the expression of the h9n2 avian influenza virus hemagglutinin gene. | over the last two decades, much attention has been paid to mdv-vectored recombinant vaccines. many factors have influenced their protective efficacy, and insertion site has been among the main influential factors for the expression of foreign genes in recombinant marek's disease virus (rmdv). to compare the transcriptional activity of different sites of rmdv, an h9n2 avian influenza virus hemagglutinin gene (aiv-h9n2-ha) expression cassette that used the bi-directional promoter of serotype 1 mdv ... | 2014 | 25034124 |
| a virulent bioluminescent and fluorescent dual-reporter marek's disease virus unveils an alternative spreading pathway in addition to cell-to-cell contact. | marek's disease virus (mdv) is a growing threat for the poultry industry. unfortunately, despite successful vaccination against the disease, mdv remains in circulation within vaccinated flocks, leading to the selection of increasingly virulent pathotypes. detailed knowledge of the virus biology and the host-virus interaction is required to improve the vaccine efficiency. in the present study, i engineered an original, dual-reporter mdv to track and quantify virus replication in vitro and in vivo ... | 2014 | 25031355 |
| generation, transmission and infectiosity of chicken mdv aerosols under experimental conditions. | to further investigate the airborne infection mechanism of marek's disease virus (mdv), a mdv aerosol infection model was established, and the generation, transmission and infectiosity of mdv aerosols were monitored in this study. two positive/negative pressure isolators, in which spf chickens were raised, were connected with a closed conduit. two repetitive trials, trial 1 (t1) and trial 2 (t2) were carried out for objective assessment. air samples were collected using the agi-30 sampler. viral ... | 2014 | 24999232 |
| direct detection of marek's disease virus in poultry dust by loop-mediated isothermal amplification. | marek's disease virus (mdv) is a serious concern for poultry production and represents a unique herpesvirus model. mdv can be shed by doubly infected chickens despite vaccination. the fully infectious mdv particles are produced in the feather follicle epithelium (ffe), and mdv remains infectious for many months in fine skin particles and feather debris. molecular biology methods including pcr and real-time pcr have been shown to be valuable for the detection of mdv dna in farm dust. recently, lo ... | 2014 | 24986718 |
| cell cycle modulation by marek's disease virus: the tegument protein vp22 triggers s-phase arrest and dna damage in proliferating cells. | marek's disease is one of the most common viral diseases of poultry affecting chicken flocks worldwide. the disease is caused by an alphaherpesvirus, the marek's disease virus (mdv), and is characterized by the rapid onset of multifocal aggressive t-cell lymphoma in the chicken host. although several viral oncogenes have been identified, the detailed mechanisms underlying mdv-induced lymphomagenesis are still poorly understood. many viruses modulate cell cycle progression to enhance their replic ... | 2014 | 24945933 |
| screening compounds of chinese medicinal herbs anti-marek's disease virus. | marek's disease (md) seriously threatens the world poultry industry and has resulted in great economic losses. chinese medicinal herbs are a rich source for lead compounds and drug candidates for antiviral treatments. | 2014 | 24920229 |
| gga-mir-26a targets nek6 and suppresses marek's disease lymphoma cell proliferation. | microrna (mirna) are a class of highly conserved, small noncoding rna that emerge as key posttranscriptional regulators in various neoplastic transformations. our previous study profiling the mirna transcriptome in marek's disease virus (mdv)-induced lymphoma revealed many novel and differentially expressed mirna, including gga-mir-26a, which was downregulated in mdv-infected spleens of chickens. in this study, differential expression of gga-mir-26a between mdv-infected and noninfected spleens a ... | 2014 | 24795301 |
| distinct expression pattern of mirnas in marek's disease virus infected-chicken splenic tumors and non-tumorous spleen tissues. | micrornas (mirnas) are small rna molecules that regulate gene expression. emerging evidence suggests that differential mirna expression is associated with viral infection and tumorigenesis. recently discovered micrornas in the marek's disease virus (mdv) genome have been suggested to have regulatory roles during mdv oncogenesis. to gain more insight into the molecular mechanisms of the tumorigenesis of mdv, we used microarrays to screen host and viral mirnas that were sensitive to infection by m ... | 2014 | 24794245 |
| small rna cloning and sequencing strategy affects host and viral microrna expression signatures. | the establishment of the microrna (mirna) expression signatures is the basic element to investigate the role played by these regulatory molecules in the biology of an organism. marek's disease virus 1 (mdv-1) is an avian herpesvirus that naturally infects chicken and induces t cells lymphomas. during latency, mdv-1, like other herpesviruses, expresses a limited subset of transcripts. these include three mirna clusters. several studies identified the expression of virus and host encoded mirnas fr ... | 2014 | 24746587 |
| interactions between marek's disease virus rispens/cvi988 vaccine strain and adenovirus field strain in chicken embryo fibroblast (cef) cultures. | the aim of the study was to determine the influence of adenovirus infection on the replication of marek's disease virus vaccine strain rispens/cvi988 during in vitro co-infection studies. adenovirus field strain jn-5/10j was isolated from sick chickens. the study was conducted in chicken embryo fibroblast cultures (cef). monolayers of cefs were infected with rispens strain and field adenovirus strain jn-5/10j with different doses (10(1.0)-10(3.0) tcid50) in the following manner: a) simultaneousl ... | 2014 | 24724464 |
| differential protein analysis of chicken skin infected with marek΄s disease virus. | the skin and feather follicle epithelia of birds infected with marek's disease virus (mdv) are the sites of infectious virus particle formation and shedding. however, the host responses and protein networks involved in the production of virus particles in the skin of mdv-infected chickens are poorly understood. this current study aimed to analyze the differential protein expression patterns in skin between mdv-infected and uninfected specific pathogen-free (spf) chickens 28 days post infection ( ... | 2014 | 24717028 |
| marek's disease virus and skin interactions. | marek's disease virus (mdv) is a highly contagious herpesvirus which induces t-cell lymphoma in the chicken. this virus is still spreading in flocks despite forty years of vaccination, with important economical losses worldwide. the feather follicles, which anchor feathers into the skin and allow their morphogenesis, are considered as the unique source of mdv excretion, causing environmental contamination and disease transmission. epithelial cells from the feather follicles are the only known ce ... | 2014 | 24694064 |
| identification and in vitro characterization of a marek's disease virus-encoded ribonucleotide reductase. | marek's disease virus (mdv) encodes a ribonucleotide reductase (rr), a key regulatory enzyme in the dna synthesis pathway. the gene coding for the rr of mdv is located in the unique long (ul) region of the genome. the large subunit is encoded by ul39 (rr1) and is predicted to comprise 860 amino acids whereas the small subunit encoded by ul40 (rr2) is predicted to be 343 amino acids long. immunoprecipitation analysis of mdv-1 (ga strain)-infected cells with t81, a monoclonal antibody specific for ... | 2013 | 24689171 |
| characterizing the molecular basis of attenuation of marek's disease virus via in vitro serial passage identifies de novo mutations in the helicase-primase subunit gene ul5 and other candidates associated with reduced virulence. | marek's disease (md) is a lymphoproliferative disease of chickens caused by the oncogenic gallid herpesvirus 2, commonly known as marek's disease virus (mdv). md vaccines, the primary control method, are often generated by repeated in vitro serial passage of this highly cell-associated virus to attenuate virulent mdv strains. to understand the genetic basis of attenuation, we used experimental evolution by serially passing three virulent mdv replicates generated from an infectious bacterial arti ... | 2014 | 24648463 |
| expression analysis of programmed death ligand 2 in tumors caused by the avian oncovirus marek's disease virus. | pd-l2 is a ligand of the immunoinhibitory receptor pd-1. here, we report functional and expression analyses of pd-l2 in tumor lesions and spleens from chickens infected with gallid herpesvirus 2 (gahv-2, marek's disease virus), which induces malignant lymphomas in chickens. we show that the expression of ifn-γ protein was decreased in pbmcs and splenocytes co-cultured with pd-l2-expressing cells and that the expression of pd-l2 mrna was significantly higher in the spleens of infected chickens in ... | 2014 | 24623086 |
| sodium tanshinone iia sulfonate inhibits the meq, ul49 and vp22 expression of marek's disease virus. | our previous studies have demonstrated that sodium tanshinone iia sulfonate (sts), a natural compound derived from salviae miltiorrhizae radix et rhizoma (danshen), could effectively inhibit marek's disease virus (mdv) infection both in vitro and in vivo, but the underlying mechanisms remain unclear. the main objective of the study was to explore the effect of sts on the meq, ul49 and vp22 expression of mdv in vitro. | 2014 | 24621515 |
| differential expression of toll-like receptor pathway genes in chicken embryo fibroblasts from chickens resistant and susceptible to marek's disease. | the toll-like receptor (tlr) signaling pathway is one of the innate immune defense mechanisms against pathogens in vertebrates and invertebrates. however, the role of tlr in non-mhc genetic resistance or susceptibility to marek's disease (md) in the chicken is yet to be elucidated. chicken embryo fibroblast (cef) cells from md susceptible and resistant lines were infected either with marek's disease virus (mdv) or treated with polyionosinic-polycytidylic acid, a synthetic analog of dsrna, and th ... | 2014 | 24604847 |
| construction of recombinant marek's disease virus (rmdv) co-expressing aiv-h9n2-na and ndv-f genes under control of mdv's own bi-directional promoter. | to qualitatively analyze and evaluate a bi-directional promoter transcriptional function in both transient and transgenic systems, several different plasmids were constructed and recombinant mdv type 1 strain gx0101 was developed to co-express a neuraminidase (na) gene from avian influenza virus h9n2 strain and a fusion (f) gene from the newcastle disease virus (ndv). the two foreign genes, ndv-f gene and aiv-na gene, were inserted in the plasmid driven in each direction by the bi-directional pr ... | 2014 | 24599338 |
| marek's disease virus may interfere with t cell immunity by tlr3 signals. | marek's disease virus (mdv) is a highly oncogenic alpha-herpesvirus that causes t cell immune suppression and malignant lymphomas in chickens. toll-like receptor (tlr) plays a dominant role in antiviral t cell immunity. however, it is unclear whether mdv induced t cell immunity is associated with tlr-mediated immunity. in this study, the expression of 28 host genes that are involved in tlr-mediated immunity and mhc-medicated t cell immunity was evaluated in chicken thymus at 7, 14, 21 and 28 day ... | 2014 | 24585377 |
| the effects of administration of ligands for toll-like receptor 4 and 21 against marek's disease in chickens. | ligands for toll-like receptors (tlrs) are known to stimulate immune responses, leading to protection against bacterial and viral pathogens. here, we aimed to examine the effects of various tlr ligands on the development of marek's disease in chickens. specific-pathogen free chickens were treated with a series of tlr ligands that interact with tlr3, tlr9 and tlr21. in a pilot study, it was determined that tlr4 and tlr21 ligands are efficacious, in that they could reduce the incidence of marek's ... | 2014 | 24530927 |
| host genetic resistance to marek's disease sustains protective efficacy of herpesvirus of turkey in both experimental and commercial lines of chickens. | marek's disease (md) remains a continual threat to the poultry industry worldwide as the md virus continues evolving in virulence. md has been controlled primarily by intensive use of vaccines since 1969. based on the antigenic and pathogenic differences of the viruses that the vaccines were derived from, commercially available md vaccines are classified into three categories, mdv-1, -2, and -3 vaccines. this study was designed to compare the protective efficacy of mdv-1 (cvi988/rispens) and mdv ... | 2014 | 24530405 |
| analysis of the mrna targetome of micrornas expressed by marek's disease virus. | marek's disease virus 1 (mdv-1), an oncogenic α-herpesvirus that induces t-cell lymphomas in chickens, serves as model system to study transformation by lymphotropic herpesviruses. like the oncogenic human γ-herpesviruses kaposi's sarcoma-associated herpesvirus (kshv) and epstein-barr virus (ebv), mdv-1 encodes several viral micrornas (mirnas). one mdv-1 mirna, mir-m4, shares the same "seed" targeting sequence with both a kshv mirna, mir-k11, and cellular mir-155. importantly, mir-m4 plays a cri ... | 2014 | 24449754 |
| in vitro and in vivo broad antiviral activity of peptides homologous to fusion glycoproteins of newcastle disease virus and marek's disease virus. | newcastle disease virus (ndv) of paramyxovirus and marek's disease virus (mdv) of herpesvirus, two of the most serious threats to the poultry industry, can give rise to complex co-infections that hinder diagnosis and prevention. in the current study, two different peptides, derived from the mdv gh (ghh2l) and gb (gbh3), respectively, exhibit antiviral activity against ndv in vitro. the potent inhibitory effect of heptad repeat 2 from fusion glycoprotein of the ndv on mdv infection also has been ... | 2014 | 24412629 |
| fluorescent tagging of vp22 in n-terminus reveals that vp22 favors marek's disease virus (mdv) virulence in chickens and allows morphogenesis study in md tumor cells. | marek's disease virus (mdv) is an alpha-herpesvirus causing marek's disease in chickens, mostly associated with t-cell lymphoma. vp22 is a tegument protein abundantly expressed in cells during the lytic cycle, which is essential for mdv spread in culture. our aim was to generate a pathogenic mdv expressing a green fluorescent protein (egfp) fused to the n-terminus of vp22 to better decipher the role of vp22 in vivo and monitor mdv morphogenesis in tumors cells. in culture, rrb-1b egfp22 led to 1 ... | 2013 | 24359464 |
| virus-encoded mir-155 ortholog is an important potential regulator but not essential for the development of lymphomas induced by very virulent marek's disease virus. | the microrna (mirna) mdv1-mir-m4, a functional mir-155 ortholog encoded by oncogenic marek's disease virus (mdv), has previously been suggested to be involved in mdv pathogenesis. using the technique of bacterial artificial chromosome mutagenesis, we have presently evaluated the potential role of mdv1-mir-m4 in the oncogenesis of the very virulent (vv) mdv strain gx0101. unexpectedly, deletions of the meq-cluster or mdv1-mir-m4 alone from the viral genome strongly decreased rather than abolished ... | 2014 | 24314636 |
| the effectiveness of mass vaccination on marek's disease virus (mdv) outbreaks and detection within a broiler barn: a modeling study. | marek's disease virus (mdv), a poultry pathogen, has been increasing in virulence since the mid twentieth century. since multiple vaccines have been developed and widely implemented, losses due to mdv have decreased. however, vaccine failure has occurred in the past and vaccine breakthroughs remain a problem. failure of disease control with current vaccines would have significant economic and welfare consequences. nevertheless, the epidemiology of the disease during a farm outbreak is not well u ... | 2013 | 24267877 |
| transcriptional profiling of meq-dependent genes in marek's disease resistant and susceptible inbred chicken lines. | marek's disease (md) is an economically significant disease in chickens caused by the highly oncogenic marek's disease virus (mdv). understanding the genes and biological pathways that confer md genetic resistance should lead towards the development of more disease resistant commercial poultry flocks or improved md vaccines. mdv meq, a bzip transcription factor, is largely attributed to viral oncogenicity though only a few host target genes have been described, which has impeded our understandin ... | 2013 | 24205146 |
| sequence variations of the mhc class i gene exon 2 and exon 3 between infected and uninfected chickens challenged with marek's disease virus. | the major histocompatibility complex (mhc) among chickens has been well established as being associated with disease resistance and pathogens infection, but the genetic differences in mhc between chickens susceptible to certain infections and those chickens that remain uninfected have not been sufficiently determined. in this study, we sought the genetic basis that may underlie differences in susceptibility to infection among chickens by challenging four groups of broilers with marek's disease v ... | 2014 | 24200589 |
| recent trends in diagnosis and control of marek's disease (md) in poultry. | marek's disease (md), caused by marek's disease virus (mdv) is a highly contagious oncogenic and neuropathic disease of chickens responsible for great economic losses to the poultry industry all around the world and characterized by development of cd4+t cell lymphomas as well as infiltration of nerves and visceral organs by lymphocytes. md is one of the most common lymphoproliferative diseases of chickens which cause mononuclear cell infiltration in one or more of the following tissues: peripher ... | 2012 | 24199474 |
| incidence of parvoviruses in chickens infected with marek's disease virus. | the aim of the study was to determine co-occurrence of marek's disease virus (mdv) and chicken parvovirus (chpv) co-occurrence in field chicken flocks. the materials for the study derived from 115 broiler chickens or layer hens originated from 23 farms with suspicion of marek's disease (md). dual infection with mdv and chpv was found in 23 (20%) examined chickens. the results obtained suggest a possibility of influence of chpv infection on efficacy of the md vaccines. | 2013 | 24195296 |
| vaccination-challenge interval markedly influences protection provided by rispens cvi988 vaccine against very virulent marek's disease virus challenge. | the rispens (cvi988) vaccine is widely used to vaccinate chickens worldwide. we tested the protective effects of the rispens vaccine against challenge with very virulent marek's disease virus (vvmdv) at various intervals at, before or after vaccination. the experiment used commercial isa brown layers and vvmdv isolate 02lar. the protective index (pi) was measured for vaccination challenge intervals (vci) of -10, -5, 0, 5 and 10 days, with the negative values indicating challenge prior to vaccina ... | 2013 | 24098951 |