Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| [reconstituting turkey herpesvirus with bacterial artificial chromosome clones]. | herpesvirus of turkey (hvt) is an alpherpesvirus and widely used as a live vaccine against marek's disease (md) because of its antigenic relationship with marek's disease virus (mdv). | 2008 | 18720848 |
| changes in the gallus gallus proteome induced by marek's disease virus. | marek's disease virus (mdv) is a highly oncogenic avian herpesvirus. we have used a modified mudpit analysis to examine the effect of mdv infection on the chicken proteome. we identified 3561 unique nonphosphorylated peptides, representing 1460 chicken proteins, in a mock-infected sample versus 4240 unique nonphosphorylated peptides, representing 1676 proteins, in an mdv-infected sample. of these unique peptides, 59.1% from the mock- and 49.6% from the mdv-infected samples were detected in both ... | 2008 | 18712901 |
| efficacy and safety of cell associated vaccines against marek's disease virus grown in a continuous cell line from chickens. | the marek's disease virus (mdv) vaccine strains cvi 988 and herpes virus of turkeys (hvt) strain fc126, usually are grown in primary chicken embryo fibroblasts (cef). we found that the strains could be grown also in the so-called jbj-1 cell line to titres in the same range as when chicken embryo fibroblasts were used. the jbj-1 cell line is a fibroblast-like continuous chicken cell line, which can be grown in flat bottom tissue culture flasks, roller bottles and on micro carriers. we investigate ... | 2008 | 18706949 |
| detection of equine herpesvirus-1 in nasal swabs of horses by quantitative real-time pcr. | early identification of inhalation-transmitted equine herpesvirus type 1 (ehv-1) infections has been facilitated by the availability of a number of real-time quantitative pcr (qpcr) tests. a direct comparison between nasal swab qpcr and traditional virus isolation (vi) requires a method for normalizing the qpcr samples and controlling for pcr inhibitors present in some clinical samples. | 2008 | 18691363 |
| [the latest advances in research of mechanisms of cell transformation induced by meq gene of marek's disease virus]. | 2008 | 18683564 | |
| vaccination against marek's disease reduces telomerase activity and viral gene transcription in peripheral blood leukocytes from challenged chickens. | we investigated whether telomerase activity and viral gene transcription were associated with protection against the rb-1b strain of marek's disease virus (mdv) in chickens vaccinated with rispens cvi988 or the herpes virus of turkey (hvt). telomerase activity in peripheral blood leukocytes (pbls) seemed to be an appropriate marker of lymphoma and levels of viral transcription were correlated with the virulence of mdv strains. vaccinated protected birds had lower levels of telomerase activity an ... | 2008 | 18680776 |
| marek's disease virus isolates with unusual tropism and virulence for ocular tissues: clinical findings, challenge studies and pathological features. | outbreaks of marek's disease (md) were diagnosed in two flocks from the same company. clinical signs, mainly blindness (>90%), but also depression, mild paralysis, and 11 to 12% mortality by 20 weeks of age were observed. md virus, serotype 1 was isolated. the isolates were designated nc-1 (flock 1) and nc-2 (flock 2). challenge experiments were conducted with these isolates and with two reference md virus strains (jm/102w and md5) in unvaccinated, turkey herpesvirus- (hvt) vaccinated and bivale ... | 1991 | 18680042 |
| comparative studies on pathogenical, virological and serological properties of marek's disease virus isolated from japanese quail and chicken. | the qm-1 strain of marek's disease virus (mdv) isolated from japanese quail (jq) induced higher mortality (96%) with md lesions in quail than the jm strain of mdv isolated from chickens (c) (21%). in contrast both viruses induced md in 90% of chickens. pathological changes produced in quail inoculated with jq-mdv or c-mdv were similar. however, the incidence of tumour lesions in the duodenum of quail inoculated with jq-mdv was significantly higher. neither virus induced tumour lesions in the duo ... | 1991 | 18679999 |
| replication of marek's disease virus in chicken feather tips containing vaccinal turkey herpesvirus dna. | the presence of herpesvirus of turkeys (hvt) dna in the feather tips of chickens vaccinated with hvt was assessed by dot blot hybridisation with a probe specific for hvt and lacking homology to mdv dna. only small amounts of hvt dna were detected in the feather tips of chickens that were vaccinated or left in contact with hvt vaccinated chickens. however when chickens were challenged with virulent mdv, hvt dna was detected in the feather tips of vaccinated chickens and the largest amount was det ... | 1991 | 18679997 |
| isolation of marek's disease virus from japanese quail with lymphoproliferative disease. | sixty-one japanese quail from eight flocks with problems of recurring outbreaks of lymphoproliferative diseases resembling marek's disease (md), were examined aetiologically. gross lymphomatous lesions were seen in 17 of the quail and 11 out of 56 quail had md virus (mdv) feather tips antigens. mdv antibody was detectable in only one of 22 quail. none of 9 quail had antibodies against reticuloendotheliosis virus (rev). no mdv was isolated from the total 42 materials of quail using cell culture t ... | 1990 | 18679919 |
| kinetics of the appearance of marek's disease virus dna and antigens in the feathers of chickens. | a comparison was made of the temporal appearance of six isolates of serotype 1 marek's disease virus (mdv) in the feathers of specific pathogen-free (spf) infected birds using three assays: agar gel precipitation (agp), enzyme-linked immunosorbent assay (elisa) and dot-blot dna hybridisation. isolate ga-5 served to standardise the in vivo pathogenicity assay, while the remaining five were recent isolates from israel. each isolate was inoculated into susceptible 4-day-old birds housed with an equ ... | 1989 | 18679904 |
| marek's disease virus-induced transient paralysis in chickens. 3. differentiation of field cases from classical marek's disease by central nervous system lesions. | vasculitis with intramural pseudocyst formation primarily in the cerebellar white matter, but also in nuclei of the medulla, resulted in leakage of igg and albumin and vacuolation of the neuropil (vasogenic oedema) in brains from chickens with clinical signs of marek's disease virus (mdv)-induced transient paralysis (tp). demyelination was absent. chickens that had recovered from tp had a restored blood-brain-barrier, indicated by the rarity of vasculitis and vascular intramural pseudocysts in t ... | 1989 | 18679873 |
| marek's disease virus-induced transient paralysis in chickens. 2. ultrastructure of central nervous system. | ultrastructural changes of the central nervous system (cns) were compared in inbred white leghorn chickens that are genetically resistant or susceptible to marek's disease virus (mdv)-induced transient paralysis (tp). widened extracellular spaces, containing granular material resembling protein were found in brains of tp-affected chickens. demyelination was absent in all chickens and intramyelinic oedema was rare, present only in tp-affected chickens. both mdv-inoculated tp-resistant and tp-susc ... | 1989 | 18679872 |
| marek's disease virus-induced transient paralysis in chickens. 1. time course association between clinical signs and histological brain lesions. | association between marek's disease virus (mdv)-induced clinical signs of transient paralysis (tp) and brain. histological lesions (vasogenic oedema and perivascular mononuclear cell cuffs) were evaluated in tp-susceptible line g-b2 chickens in a time sequence study. the most consistent histological lesions were seen in the cerebellum. leakage of albumin and vacuolation were parallel in development with clinical signs, but preceded the clinical signs by 6 to 12 h. during resolution of signs, a p ... | 1989 | 18679871 |
| effect of reticuloendotheliosis virus and infectious bursal disease virus on marek's disease herpesvirus latency. | birds infected with reticuloendotheliosis virus (rev) were exposed to marek's disease virus (mdv) to determine if the establishment of mdv latency was affected by rev-induced immunosuppression, while other chickens, already latently infected with mdv, were challenged with rev or infectious bursal disease virus (ibdv) to determine if the consequent immunosuppression caused a return to cytolytic infection. immunosuppression was assessed by in vitro mitogen stimulation assays with spleen cells. lat ... | 1989 | 18679859 |
| host responses in the bursa of fabricius of chickens infected with virulent marek's disease virus. | the bursa of fabricius serves as an important tissue in the process of marek's disease virus (mdv) pathogenesis, since b cells of the bursa harbor the cytolytic phase of mdv replication cycle. in the present study, host responses associated with mdv infection in the bursa of fabricius of chickens were investigated. the expression of mdv phosphoprotein (pp)38 antigen, mdv glycoprotein (gb) and mdv viral interleukin (vil)-8 transcripts was at the highest at 4 days post-infection (d.p.i.) and then ... | 2008 | 18675437 |
| avian encephalomyelitis following oral vaccination. | outbreaks of clinical avian encephalomyelitis (ae) which developed after vaccination of 14-week-old birds by the oral route are reported. mortality during weeks 2 to 5 following vaccination reached 2%. experimental studies showed that, in contrast to popular opinion, ae vaccine virus given orally can spread to the central nervous system and produce encephalomyelitis (mild). the severity of the vaccine induced lesions was not affected by chicken anaemia virus (cav) infection 2 weeks before ae vac ... | 1994 | 18671111 |
| interaction between chicken anaemia virus and live newcastle disease vaccine. | three groups of 150 spf chickens were spray-vaccinated with live newcastle disease la sota-type vaccine (clone 30) at one day of age, and another three groups were ndv spray-vaccinated at 10 days of age. in each of the two series of ndv-vaccinated groups, one group also received at day-old 10(5) tcid50 of chicken anaemia virus (cav) also and another group 10(5) tcid50 of cav plus a low dose of virulent marek's disease virus (mdv). after one week, chickens of the groups which had been ndv-vaccina ... | 1994 | 18671091 |
| effects of age at infection with serotype 2 marek's disease virus on enhancement of avian leukosis virus-induced lymphomas. | inoculation of susceptible, 15i5 x 7i chickens with serotype 2 marek's disease virus (mdv) at various ages had no influence on the development of avian leukosis virus (alv)-induced viraemia or antibody in chickens infected with alv and turkey herpesvirus (hvt) at hatch. however, the incidence of alv-induced lymphoma (ll) was significantly higher in chickens infected with alv and hvt at hatch and inoculated with serotype 2 mdv up to 6 weeks of age than in chickens receiving serotype 2 mdv at 8 to ... | 1993 | 18671041 |
| detection of reticuloendotheliosis virus infection using the polymerase chain reaction. | the polymerase chain reaction (pcr) was shown to be a sensitive and useful method for detection of infection by members of the group of avian reticuloendotheliosis virus (rev). genomic dna extracted from chick embryo fibroblasts (cefs), blood and tumours of chickens experimentally infected with the spleen necrosis virus (snv) strain of rev was used as the target for chain elongation. deoxyoligonucleotide primers that encompass a portion of the unique 3', repeat and unique 5' region of the long t ... | 1993 | 18671039 |
| cytopathology caused by the ac-1 isolate of marek's disease virus in the feather follicle epidermis. | the ac-1 strain of marek's disease herpesvirus (mdv), recently isolated from an outbreak of marek's disease in vaccinated chickens, was used for intraperitoneal inoculation of one-day-old single comb white leghorns. chicks were necropsied 12 to 32 days post inoculation and skin was collected for electron microscopic studies. this paper focuses on early stages of mdhv development in feather follicle epithelial cells and on cytoplasmic changes that occur in formation and release of virus particles ... | 1993 | 18671018 |
| jmv-1 stimulation of avian natural killer cell activity. | the phenotypic characterization of the non-productive, marek's disease virus-transformed, lymphoblastoid cell line, jmv-1 and the immunological effects of its cell-free culture supernatant were examined. it was verified that the jmv-1 cell line is an activated t-helper cell line that bears antigens indicative of t-cell activation, and it is not a natural killer or cytotoxic t-cell line. furthermore, the jmv-1 cell line was shown to be unique among marek's disease-transformed cell lines in that j ... | 1992 | 18670936 |
| characterization of very virulent marek's disease viruses isolated in japan. | pathogenicity of two isolates of marek's disease virus (mdv), ms1 and ms2, from chickens was examined in two genetically different strains of chickens, md-susceptible p-2 chickens and less susceptible pdl-1 chickens. the isolates induced an early mortality syndrome unassociated with lymphoproliferative lesions in p-2 chickens. there were no significant differences in pathogenicity between our isolates and the md/5 strain of very virulent mdv (vvmdv) in both p-2 and pdl-1 chickens. protective ind ... | 1992 | 18670921 |
| load of challenge marek's disease virus dna in blood as a criterion for early diagnosis of marek's disease tumors. | outbreaks of marek's disease (md) in vaccinated flocks still occur sporadically and lead to economic losses. unfortunately, adequate methods to predict md outbreaks are lacking. in the present study, we have evaluated whether high load of challenge md virus (mdv) dna in peripheral blood could aid in the early diagnosis of md and in monitoring efficacy of vaccines against md. one experiment was conducted to simulate field conditions by combining various vaccines (turkey herpesvirus [hvt] and hvt ... | 2008 | 18646447 |
| some observations on naturally occurring neoplasms of domestic fowls in the state of victoria, australia (1977-87). | in the 10 years to november 1987, 33 different types of naturally occurring neoplasms were diagnosed in 2281 domestic fowls submitted for necropsy examination. the most prevalent type was lymphoma (1825/2281 = 80%) including two cases in chickens from a flock free from marek's disease virus, exogenous avian leukosis viruses and reticuloendotheliosis virus; the remaining lymphomas were diagnosed on gross and/or histological criteria as marek's disease (1069) or lymphoid leukosis (754). of the non ... | 1996 | 18645870 |
| sequential skin lesions in chickens experimentally infected with marek's disease virus. | skin biopsies taken at weekly intervals from the same specific-pathogen free (spf) chickens inoculated with md/5 marek's disease virus revealed two distinctive patterns of perifollicular cutaneous lesions, tumour-associated and non-tumour-associated. the tumour-associated pattern was subdivided into two types. the progressive type was manifested by a continuous increase of lymphoid cell aggregates (lca) in the skin, resulting in the development of gross skin tumours with or without visceral tumo ... | 1996 | 18645861 |
| a flow cytometric method for identifying marek's disease virus pp38 expression in lymphocyte subpopulations. | identification of marek's disease virus-infected lymphocytes is essential for a full understanding of the pathogenesis of marek's disease. this paper describes the development of a simple, quantitative and reproducible flow cytometric technique for the identification of the phenotype of marek's disease virus-infected lymphocytes. the method is based upon the detection of the marek's disease virus-specific phosphoprotein pp38, in saponin-permeabilized lymphocytes, using the monoclonal antibody bd ... | 1996 | 18645857 |
| enhancement of reticuloendotheliosis virus-induced bursal lymphomas by serotype 2 marek's disease virus. | the effect of serotype 2 and 3 marek's disease virus (mdv) vaccines on the pathogenesis of reticuloendotheliosis virus (rev)-induced bursal and non-bursal lymphomas was examined in chickens of rprl lines 15i(5) x 7(1) and 6(3) x 0, respectively. at hatch, chickens were vaccinated with strain 301b/1 of serotype 2 mdv or strain fc126 of turkey herpesvirus (hvt), a serotype 3 mdv and inoculated with spleen necrosis virus (snv), a non-defective strain of rev. in another experiment, bursas from 14-we ... | 1996 | 18645839 |
| an outbreak of lymphomas in commercial broiler breeder chickens vaccinated with a fowlpox vaccine contaminated with reticuloendotheliosis virus. | gross and microscopic examinations of affected tissues from chickens of two commercial broiler breeder flocks aged 27 and 31 weeks revealed lesions of visceral lymphomas with bursal involvement in some chickens. reticuloendotheliosis virus (rev), but not avian leukosis virus (alv), was isolated from blood of affected chickens. furthermore, dna extracted from tumours tested positive for rev, but not for alv or marek's disease virus by polymerase chain reaction (pcr) test. attempts to determine th ... | 1996 | 18645835 |
| protection studies against marek's disease using baculovirus-expressed glycoproteins b and c of marek's disease virus type 1. | glycoproteins b (mdv1-gb) and c (mdv1-gc) of marek's disease virus type 1 (mdv 1) expressed by baculovirus recombinants [racnpv(s)] were investigated for their ability to confer protective immunity in chickens against virulent mdv1 challenge. immunization of chickens with racnpv-expressed mdv1-gb induced antibody against mdv1 and resulted in strong protection against the lethal challenge with mdv1. in contrast, immunization of chickens with racnpv-expressed mdv1-gc induced antibody against mdv1, ... | 1996 | 18645833 |
| attenuation of lymphoid leukosis enhancement by serotype 2 marek's disease virus. | serotype 2 marek's disease virus (mdv), already known to augment the protective efficacy of turkey herpes virus (hvt) vaccine against md, may also enhance the frequency of lymphoid leukosis (ll) in retrovirus-infected chickens of certain strains. ll enhancement refers to an increase in frequency and decrease in latent period for development of ll, and is measured by comparison of tumour responses in retro-virus-infected, md-vaccinated chickens to those of retrovirus-infected control chickens. ll ... | 1995 | 18645823 |
| extravascular haemolytic anaemia in chicks infected with highly pathogenic marek's disease viruses. | chicks were infected at 1 day of age with highly pathogenic ac-1 or rb-1b isolates of marek's disease virus and 14 to 36 days post-exposure they were bled for haematocrits and euthanized. at necropsy, specimens were collected for light and electron microscopy. both viruses caused significant reductions in packed cell volume (p<0.01). hyperplasia of reticuloendothelial (re) cells in the liver was a common finding in chicks that were ill from infection with ac-1 or rb-1b viruses. erythrophagocytos ... | 1995 | 18645797 |
| use of the polymerase chain reaction for the diagnosis of natural infection of chickens and turkeys with marek's disease virus and reticuloendotheliosis virus. | marek's disease (md) is a highly contagious lymphoproliferative disease of chickens caused by a herpesvirus, while reticuloendotheliosis (rev) virus is an avian c-type retrovirus that causes bursal and nonbursal lymphomas which often closely resemble mdv lymphomas. to provide a rapid and sensitive means of diagnosing and differentiating between these two neoplastic conditions, we have applied the pcr. the primers chosen to detect mdv sequences flank the 132 bp tandem repeat of the bamhi-h fragme ... | 1995 | 18645767 |
| functional homologies between avian and human alphaherpesvirus vp22 proteins in cell-to-cell spreading as revealed by a new cis-complementation assay. | vp22, encoded by the ul49 gene of marek's disease virus (mdv), is indispensable for virus cell-to-cell spreading. we show herein that mdv ul49 can be functionally replaced with avian and human viral orthologs. replacement of mdv vp22 with that of avian gallid herpesvirus 3 or herpesvirus of turkey, whose residue identity with mdv is close to 60%, resulted in 73 and 131% changes in viral spreading, respectively. in contrast, vp22 replacement with human herpes simplex virus type 1 resulted in 14% ... | 2008 | 18632866 |
| [construction of marek's disease virus serotype 814 strain as an infectious bacterial artificial chromosome]. | the aim of this study was to construct the complete genome of marek's disease virus serotype 814 strain as an infectious bacterial artificial chromosome (bac). using self-designed selection marker eco-gpt (1.3 kb) and bac vector pbelobac11 (7.5 kb), we constructed the transfer plasmid puab-gpt-bac11. the plasmid puab-gpt-bac11 and mdv total-dna were cotransfected into secondary cefs; we put the virus-containing cells in selection medium for eight rounds and obtained purified recombinant viruses. ... | 2008 | 18616164 |
| variations in the h/aca box sequence of viral telomerase rna of isolates of cvi988 rispens vaccine. | the use of the complete dna sequence for the marek's disease virus (mdv) serotype 1 vaccine strain cvi988 rispens in comparative genomic studies with virulent strains of mdv has revealed the presence of a number of insertions, deletions and single-nucleotide polymorphisms. in this study, we investigated a snp in the h/aca box of the viral rna subunit of telomerase (vtr). we sequenced vtr from four different batches of cvi988 vaccine originating from a single commercial company. the a-to-g mutati ... | 2008 | 18594940 |
| molecular cloning and sequence analysis of the duck enteritis virus ul5 gene. | duck enteritis virus (dev) is a herpesvirus that causes an acute, contagious, and fatal disease. in the present article, the dev ul5 gene was cloned and sequenced from a vaccine virus. according to the consensus sequence of herpesvirus ul5 and ul3 gene degenerate oligonucleotide primers were designed and were used in the polymerase chain reaction (pcr) to amplify dna products with 4577 bp in size. dna sequence analysis revealed a 2568 bp open reading frame (orf) encoding a 855 amino acid polypep ... | 2008 | 18582977 |
| high allelic polymorphism, moderate sequence diversity and diversifying selection for b-nk but not b-lec, the pair of lectin-like receptor genes in the chicken mhc. | we previously characterised the c-type lectin-like receptor genes b-nk and b-lec, located next to each other in opposite orientations in the chicken major histocompatibility complex (mhc). we showed that b-nk is an inhibitory receptor expressed on natural killer cells, whereas b-lec is an activation-induced receptor with a broader expression pattern. it is interesting to note that the chicken mhc has been linked with resistance or susceptibility to marek's disease virus (mdv), an oncogenic herpe ... | 2008 | 18574582 |
| inhibition of marek's disease virus replication by retroviral vector-based rna interference. | rna interference (rnai) is a promising antiviral methodology. we recently demonstrated that retroviral vectors expressing short-hairpin rnas (shrna-mirs) in the context of a modified endogenous micro-rna (mirna) can be effective in reducing replication of other retroviruses in chicken cells. in this study, similar rnai vectors are shown to inhibit replication of the avian herpesvirus, marek's disease virus (mdv, also known as gallid herpesvirus type 2), and its close relative, herpesvirus of tur ... | 2008 | 18570965 |
| expression of cytotoxicity-associated genes in marek's disease virus-infected chickens. | cytotoxic host responses to marek's disease virus (mdv) have been attributed to both natural killer (nk) cells and cytotoxic t lymphocytes (ctls). however, the mechanisms of cell lysis initiated by these cytotoxic responses during mdv infection are not well defined. therefore, the current study was aimed at elucidating the molecular mechanisms of host cytotoxic responses to mdv infection by investigating the expression of genes in the cell lysis pathway involving granzyme a. genes encoding cytol ... | 2008 | 18570592 |
| kinetics of marek's disease virus (mdv) infection in broiler chickens 1: effect of varying vaccination to challenge interval on vaccinal protection and load of mdv and herpesvirus of turkey in the spleen and feather dander over time. | two experiments in commercial broiler chickens vaccinated with herpesvirus of turkeys (hvt) and challenged with marek's disease virus (mdv) investigated the effects of the vaccination-to-challenge interval (vci) on vaccinal protection against marek's disease, and the kinetics of mdv and hvt load in the spleen and feather dander determined using real-time quantitative polymerase chain reaction. experiment 1 in isolators tested vci of 2, 4 and 7 days, while experiment 2 in floor pens tested vci of ... | 2008 | 18568648 |
| [cloning and sequence analysis of the meq gene of 4 marek's disease virus isolates from china]. | earlier studies have determined that the repeat regions of oncogenic serotype 1 mdv (marek's disease virus) encode a basic leucine zipper protein, meq, which structurally resembles the jun/fos family of transcriptional activators. meq has been suggested as the mdv-associated oncogene. in this paper, based on the published sequence of meq gene of ga strain of mdv, a pair of primers were designed and synthesized. meq gene orf (open reading frame) of the four chinese local mdv isolates, the referen ... | 2008 | 18533343 |
| clustering of mutations within the inverted repeat regions of a serially passaged attenuated gallid herpesvirus type 2 strain. | marek's disease (md) is the leading cause of losses in chicken production in the world. over the past 40 years significant progress has been made in the control of md through the use of vaccines which reduce or delay tumor formation in vaccinated flocks. however, these vaccines fail to induce an immune response that protects against infection and virus shedding. little is known about the genetic changes that lead to attenuation and are necessary for the generation of vaccine strains. previous re ... | 2008 | 18516669 |
| central nervous system lesions induced experimentally by a very virulent strain of marek's disease virus in marek's disease-resistant chickens. | the histological lesions of central nervous system (cns) in marek's disease-resistant chickens inoculated with a very virulent marek's disease virus strain (vvmdv), md/5, were examined. this vvmdv induced high incidences of cns lesions as well as visceral and peripheral nerve lesions. the principal histopatho-logical changes of cns consisted of non-suppurative meningoencephalomyelitis and lymphomatous lesion, which were categorized into two types, non-necrotizing and necrotizing. the main change ... | 1998 | 18484036 |
| differential diagnosis of two paralytic conditions affecting young chickens with emphasis on pcr findings. | two paralytic conditions affecting flocks of young commercial chickens that were indistinguishable histopathologically from lesions caused by marek's disease virus (mdv) were investigated. the first, transient paralysis, was observed only in broilers while the second condition, a spastic paralysis, was seen in replacement white leghorn pullets aged between 6 and 16 weeks. pcr examination of dna extracted from the blood, brain and spleens of affected birds using primers specific for mdv serotype ... | 1998 | 18484022 |
| isolation of highly cytolytic mdv strains from germany and spain. | four serotype 1 marek's disease virus (mdv) strains were isolated from marek's disease (md) outbreaks in germany and spain and their virulence was tested in spf white leghorn chickens. two of the isolates from germany (mr48/1-2 and /2-8) induced early mortality from cytolytic md in 25% of the chickens whereas one isolate from germany (mr48/3-16) caused early mortality in 58% of the inoculated chickens. histological examination showed severe depletion of the lymphoid tissue of the bursa of fabric ... | 1998 | 18484005 |
| effect of multiple cell culture passages on the biological behaviour of chicken anaemia virus. | the cux-1 isolate of chicken anaemia virus (cav) was passaged over 320 times in marek's disease virus transformed chicken lymphoblastoid (mdcc-msb1) cells. comparison of the infectivity titres of virus pools derived from viruses that had received 0 (p0), 49 (p49), 170 (p170) and 320 (p320) passages in our laboratory indicated that the yields of infectious virus increased over 100-fold with passage number from p0 to p170. p320 exhibited unusual cell culture growth characteristics in that, unlike ... | 1998 | 18483967 |
| significance of marek's disease virus serotype 1-specific phosphorylated proteins in marek's disease skin lesions. | skin tissues were obtained from 12 chickens showing marek's disease (md) skin tumour induced by a very virulent md/5 strain of marek's disease virus serotype 1 (mdvl) and taken from 24 field broiler chickens (8 to 9-weeks-old) manifesting md skin tumour. they were examined by the immunohistochemical method in order to examine the topographic expression of mdv1-specific phosphorylated proteins (pp) and by the reverse-transcription polymerase chain reaction following southern hybridization to anal ... | 1997 | 18483940 |
| phenotype analysis of lymphoid cells in marek's disease of cd4(+) or cd8(+) t-cell-deficient chickens: occurrence of double negative t-cell tumour. | chickens rendered either cd4(+) or cd8(+) t-cell-deficient by thymectomy and subsequent inoculation of anti-cd4 or anti-cd8 monoclonal antibody (mab), were infected with marek's disease herpesvirus (mdv). all the non-treated control (4/4) and cd8-deficient chickens (5/5) formed gross tumours. however, one of three cd4(+) t-cell-deficient chickens developed gross tumours. histologically, all chickens had tumourous lesions in the liver and nerve fibres. in cd4(+) t-cell-deficient chickens, the phe ... | 1997 | 18483926 |
| marek's disease virus induces th-2 activity during cytolytic infection. | marek's disease (md) is a lymphoproliferative disease of chickens that is caused by a highly cell-associated oncogenic alpha-herpesvirus, marek's disease virus (mdv). the role of cytokines and other related proteins in md pathogenesis and immunity is poorly understood. the aim of this study was to examine the transcriptional profiling of a panel of cytokines and other immune-related genes in the splenic tissues of chickens infected with a highly oncogenic strain of mdv during cytolytic infection ... | 2008 | 18433333 |
| deep sequencing of chicken micrornas. | the use of new, deep sequencing technologies has greatly accelerated microrna discovery. we have applied this approach to the identification of chicken micrornas and to the comparison of micrornas in chicken embryo fibroblasts (cef) infected with marek's disease virus (mdv) to those present in uninfected cef. | 2008 | 18430245 |
| different signaling pathways expressed by chicken naive cd4(+) t cells, cd4(+) lymphocytes activated with staphylococcal enterotoxin b, and those malignantly transformed by marek's disease virus. | proteomics methods, based on liquid chromatography and tandem mass spectrometry, produce large "shotgun" proteomes that are most appropriately compared not at the level of differentially expressed proteins only but at the more comprehensive level of biological networks and pathways. this is now possible with the emergence of functional annotation databases and tools, databases of canonical pathways and molecular interactions and computational text mining tools. here, we used shotgun proteomics, ... | 2008 | 18412384 |
| current developments in avian influenza vaccines, including safety of vaccinated birds as food. | until recently, most vaccines against avian influenza were based on oil-emulsified inactivated low- or high-pathogenicity viruses. now, recombinant fowl pox and avian paramyxovirus type 1 vaccines with avian influenza h5 gene inserts (+ or - n1 gene insert) are available and licensed. new technologies might overcome existing limitations to make available vaccines that can be grown in tissue culture systems for more rapid production; provide optimized protection, as a result of closer genetic rel ... | 2007 | 18411943 |
| transcriptional analysis of host responses to marek's disease virus infection in genetically resistant and susceptible chickens. | marek's disease virus (mdv) is a cell-associated oncogenic herpesvirus that targets b cells and t cells, inducing lymphoid tumours in chickens. genetic resistance to marek's disease (md) is regulated in a polygenic fashion. in this study, we sought to compare the gene expression profiles following infection of birds that are genetically resistant or susceptible to md (with the b21 and b19 haplotypes respectively at the mhc locus), including comparisons to uninfected controls. on days 4, 7, 14 an ... | 2008 | 18371127 |
| analysis of the expression profiles of marek's disease virus-encoded micrornas by real-time quantitative pcr. | micrornas (mirnas) are a large class of endogenous approximately 22-nucleotide long non-coding rnas involved in post-transcriptional silencing of gene expression by translational repression or direct cleavage of the target mrnas. several hundreds of mirnas have now been identified in a wide range of organisms including many viruses. marek's disease virus serotype 1 (mdv-1) is a highly contagious oncogenic herpesvirus that induces fatal t-cell lymphomas in chickens. mdv-1 has been shown recently ... | 2008 | 18355930 |
| sequence determination of a mildly virulent strain (cu-2) of gallid herpesvirus type 2 using 454 pyrosequencing. | the complete dna sequence of the mildly virulent gallid herpesvirus type 2 strain cu-2 was determined and consists of 176,922 bp with an overall gene organization typical of class e herpesviruses. phylogenetically, this strain partitions in its own branch between the virulent strains rb-1b, md11, and md5, and the vaccine strain cvi988. overall, the genome of cu-2 is more similar to that of cvi988, with identically sized unique short regions of 11,651 bp. as in cvi988, an insertion of 177 bp was ... | 2008 | 18351449 |
| [the n1-18 terminus of marek's disease virus vp22 is essential for protein transduction]. | we previously showed some differences in marek's disease virus (mdv) vp22 gene between virulent and avirulent strains, in the deletion from 201aa to 206aa, namely 201tksert206. in this study, vp22 genes were amplified from strains: cvi988/rispens and ga. and then the fragments were subcloned into pcdna3.1/zeo(+), respectively, which were co-expressed with an enhancer green fluorescent protein (egfp) after transfection into cos-1 cells. as with both human herpesvirus 1 and bovine herpesvirus 1 vp ... | 2008 | 18338583 |
| recombinant marek's disease virus (mdv) lacking the meq oncogene confers protection against challenge with a very virulent plus strain of mdv. | marek's disease virus (mdv) encodes a basic leucine-zipper protein, meq, that shares homology with the jun/fos family of transcriptional factors. conclusive evidence that meq is an oncogene of mdv came from recent studies of a meq-null virus, rmd5 delta meq. this virus replicated well in vitro, but was non-oncogenic in vivo. further characterization of this virus in vivo indicated that the meq gene is dispensable for cytolytic infection since it replicated well in the lymphoid organs and feather ... | 2008 | 18313812 |
| deletion of the marek's disease virus ul41 gene (vhs) has no measurable effect on latency or pathogenesis. | marek's disease is an economically important disease of poultry and is caused by an alphaherpesvirus, marek's disease virus (mdv). the predicted protein product of the mdv ul41 open reading frame has significant protein sequence identity with the virion host shutoff (vhs) protein gene in other alphaherpesviruses. to determine whether the mdv ul41 gene functions as a vhs protein, we utilized a transient co-transfection assay and demonstrated that the mdv ul41 protein was as active in degrading rn ... | 2008 | 18311518 |
| enzymatically inactive u(s)3 protein kinase of marek's disease virus (mdv) is capable of depolymerizing f-actin but results in accumulation of virions in perinuclear invaginations and reduced virus growth. | marek's disease (md) is a highly contagious, lymphoproliferative disease of chickens caused by the cell-associated md virus (mdv), a member of the alphaherpesvirus subfamily. in a previous study we showed that the absence of the serine/threonine protein kinase (pu(s)3) encoded in the mdv unique-short region resulted in accumulation of primarily enveloped virions in the perinuclear space and significant impairment of virus growth in vitro. it was also shown that pu(s)3 is involved in actin stress ... | 2008 | 18304599 |
| transcriptional profiling of marek's disease virus genes during cytolytic and latent infection. | marek's disease (md), a lymphoproliferative disease of chicken is caused by a highly cell-associated alpha-herpesvirus, marek's disease virus (mdv). mdv replicates in chicken lymphocytes and establishes a latent infection within cd4(+) t cells. the expression analysis of limited viral transcripts have revealed differences in gene expression pattern during cytolytic and latent phases of mdv infection. in this study, we conducted a global gene expression profiling of mdv using oligonucleotide-base ... | 2008 | 18266100 |
| microrna profile of marek's disease virus-transformed t-cell line msb-1: predominance of virus-encoded micrornas. | research over the last few years has demonstrated the increasing role of micrornas (mirnas) as major regulators of gene expression in diverse cellular processes and diseases. several viruses, particularly herpesviruses, also use the mirna pathway of gene regulation by encoding their own mirnas. marek's disease (md) is a widespread lymphomatous neoplastic disease of poultry caused by the highly contagious marek's disease virus type 1 (mdv-1). recent studies using virus-infected chicken embryo fib ... | 2008 | 18256158 |
| antibody response of chickens to serotype 1, 2, or 3 marek's disease vaccines based on elisa with infected cells as antigen. | an enzyme-linked immunosorbent assay (elisa) was applied to evaluate the antibody response of commercial white leghorn chickens to vaccination against marek's disease (md) at hatch (day 0) with serotype-1 (rispens), -2 (sb-1), or -3 (turkey herpesvirus, hvt) vaccine virus and to challenge on day 21 with md virus. antigens for the test were whole chicken embryo fibroblast cells infected with rispens, sb-1, or hvt. the chickens were progeny of stock that had been vaccinated with hvt, and on day 21 ... | 2007 | 18251413 |
| characterization of lorf11, a unique gene common to the three marek's disease virus serotypes. | the unique open reading frame 11 (lorf11) of marek's disease virus (mdv) is present in all three serotypes of mdv and is located in the unique long region of the mdv genome. in the serotype 1 md5 genome, lorf11 comprises 2711 nucleotides and encodes a predicted protein of 903 amino acids. in order to study the biological function of lorf11 we deleted it from the mdv cosmid a6 by using the reca-assisted restriction endonuclease cleavage method. the recombinant cosmid, a6deltalorf11, was transfect ... | 2007 | 18251393 |
| characterization of a newly developed chicken 44k agilent microarray. | the development of microarray technology has greatly enhanced our ability to evaluate gene expression. in theory, the expression of all genes in a given organism can be monitored simultaneously. sequencing of the chicken genome has provided the crucial information for the design of a comprehensive chicken transcriptome microarray. a long oligonucleotide microarray has been manually curated and designed by our group and manufactured using agilent inkjet technology. this provides a flexible and po ... | 2008 | 18237426 |
| self-excision of the bac sequences from the recombinant marek's disease virus genome increases replication and pathogenicity. | cloning of full length genomes of herpesviruses as bacterial artificial chromosomes (bac) has greatly facilitated the manipulation of the genomes of several herpesviruses to identify the pathogenic determinants. we have previously reported the construction of the bac clone (prb-1b5) of the highly oncogenic marek's disease virus (mdv) strain rb-1b, which has proven to be a valuable resource for elucidating several oncogenic determinants. despite the retention of the bac replicon within the genome ... | 2008 | 18230192 |
| quantitative evaluation of viral fitness due to a single nucleotide polymorphism in the marek's disease virus ul41 gene via an in vitro competition assay. | marek's disease, a t cell lymphoma, is an economically important disease of poultry caused by the marek's disease virus (mdv), a highly cell-associated alphaherpesvirus. a greater understanding of viral gene function and the contribution of sequence variation to virulence should facilitate efforts to control marek's disease in chickens. to characterize a naturally occurring single nucleotide polymorphism (snp; ay510475:g.108,206c>t) in the mdv ul41 gene that results in a missense mutation (aas01 ... | 2008 | 18082901 |
| mapping quantitative trait loci affecting susceptibility to marek's disease virus in a backcross population of layer chickens. | marek's disease (md), caused by the oncogenic md avian herpes virus (mdv), is a major source of economic losses to the poultry industry. a reciprocal backcross (bc) population (total 2052 individuals) was generated by crossing two partially inbred commercial leghorn layer lines known to differ in mdv resistance, measured as survival time after challenge with a (vv+) mdv. qtl affecting resistance were identified by selective dna pooling using a panel of 198 microsatellite markers covering two-thi ... | 2007 | 18073438 |
| a herpesvirus ubiquitin-specific protease is critical for efficient t cell lymphoma formation. | the herpesvirus ubiquitin-specific protease (usp) family, whose founding member was discovered as a protease domain embedded in the large tegument protein of herpes simplex virus 1 (hsv-1), is conserved across all members of the herpesviridae. whether this conservation is indicative of an essential function of the enzyme in vivo has not yet been established. as reported here, usp activity is conserved in marek's disease virus (mdv), a tumorigenic alphaherpesvirus. a single amino acid substitutio ... | 2007 | 18056809 |
| correlation of marek's disease herpesvirus vaccine virus genome load in feather tips with protection, using an experimental challenge model. | we previously developed a real-time polymerase chain reaction (pcr) assay for absolute quantitation of serotype 1 marek's disease virus in feather tips of chickens, and this has been used clinically to monitor a flock's response following vaccination with cvi988, an attenuated serotype 1 strain. the level of vaccine virus in feather tips associated with protection against challenge by virulent virus is not known. here, we used an experimental challenge model, in which one dose of vaccine gives o ... | 2007 | 17994325 |
| marek's disease virus-induced skin leukosis in scaleless chickens: tumor development in the absence of feather follicles. | marek's disease virus (mdv) is an oncogenic cell-associated herpesvirus that causes t-cell lymphoma in chickens. lymphoproliferative neoplasms in marek's disease (md) occur in various organs and tissues, including the viscera, peripheral nerves, skin, gonads, and musculatures. mdv is restrictively produced in the feather follicle epithelial (ffe) cells, and it gains access to the external environment via infected cells or as infectious enveloped cell-free virus particles. the goals of the presen ... | 2007 | 17992931 |
| optimization of methods for the isolation of marek's disease viruses in primary chicken cell cultures. | a real-time pcr was used to measure increases in viral dna in marek's disease virus (mdv)-infected primary chicken cell cultures in order to optimize methods for viral isolation. serotype-1 and -3 vaccine and serotype-1 challenge strains exhibited similar growth characteristics, with increases in viral dna being proportional to inoculum size. studies of viral growth revealed a linear relationship between increase in mdv copy number and infectious titre, although the rate of increase for copy num ... | 2008 | 17976832 |
| ty3 gag3 protein forms ordered particles in escherichia coli. | the yeast retrovirus-like element ty3 gag3 gene encodes a gag3 polyprotein analogous to retroviral gag. gag3 lacks matrix, but contains capsid, spacer, and nucleocapsid domains. expression of a ty3 gag3 or capsid domain optimized for expression in escherichia coli was sufficient for ty3 particle assembly. virus-like ordered particles assembled from gag3 were similar in size to immature particles from yeast and contained nucleic acid. however, particles assembled from the ca domain were variable ... | 2008 | 17964628 |
| host responses are induced in feathers of chickens infected with marek's disease virus. | control measures are ineffective in curtailing marek's disease virus (mdv) infection and replication in the feather follicle epithelium (ffe). therefore, vaccinated birds which subsequently become infected with mdv, shed the virulent virus although they remain protected against disease. the present study investigated host responses generated against mdv infection in the feather. we observed that in parallel with an increase in viral genome load and viral replication in the feather, there was a g ... | 2008 | 17949771 |
| creation of diversity in the animal virus world by inter-species and intra-species recombinations: lessons learned from poultry viruses. | the biological diversity within viruses is one of the largest found in all other forms of nature. many mechanisms contribute to virus diversity and include incorporating genetic material from the host, recombination between viruses belonging to the same or to a different family, and even recombination between viruses normally infecting different hosts. in particular, avian viruses can utilize all three of these mechanisms to generate new viruses. it is well documented that recombinations can occ ... | 2008 | 17922180 |
| animal vaccination and the evolution of viral pathogens. | despite reducing disease, vaccination rarely protects against infection and many pathogens persist within vaccinated animal populations. circulation of viral pathogens within vaccinated populations may favour the development of vaccine resistance with implications for the evolution of virus pathogenicity and the emergence of variant viruses. the high rate of mutations during replication of ribonucleic acid (rna) viruses is conducive to the development of escape mutants. in vaccinated cattle, unu ... | 2007 | 17892155 |
| morphogenesis of a highly replicative egfpvp22 recombinant marek's disease virus in cell culture. | marek's disease virus (mdv) is an alphaherpesvirus for which infection is strictly cell associated in permissive cell culture systems. in contrast to most other alphaherpesviruses, no comprehensive ultrastructural study has been published to date describing the different stages of mdv morphogenesis. to circumvent problems linked to nonsynchronized infection and low infectivity titers, we generated a recombinant mdv expressing an enhanced green fluorescent protein fused to vp22, a major tegument ... | 2007 | 17855520 |
| development of a nested polymerase chain reaction method to detect oncogenic marek's disease virus from feather tips. | for the easy survey of marek's disease virus (mdv), feather tip-derived dna from mdv-infected chickens can be used because feather tips are easy to collect and feather follicle epithelium is known to be the only site of productive replication of cell-free mdv. to develop a diagnostic method to differentiate highly virulent strains of mdv from the attenuated mdv vaccine strain, cvi988, which is widely used, nested polymerase chain reaction (pcr) was performed to detect a segment of the meq gene i ... | 2007 | 17823389 |
| effects of vaccine dose, virus challenge dose and interval from vaccination to challenge on protection of broiler chickens against marek's disease virus challenge. | to examine the effects of varying the doses of turkey herpesvirus (hvt) vaccine and marek's disease virus (mdv) challenge at two intervals after vaccination on the protection of chickens against challenge with mdv. | 2007 | 17760936 |
| comparative sequence analysis of a highly oncogenic but horizontal spread-defective clone of marek's disease virus. | marek's disease virus (mdv) is a cell-associated alphaherpesvirus that induces rapid-onset t-cell lymphomas in poultry. mdv isolates vary greatly in pathogenicity. while some of the strains such as cvi988 are non-pathogenic and are used as vaccines, others such as rb-1b are highly oncogenic. molecular determinants associated with differences in pathogenicity are not completely understood. comparison of the genome sequences of phenotypically different strains could help to identify molecular dete ... | 2007 | 17721813 |
| genomics and marek's disease virus. | marek's disease virus (mdv), a lymphotrophic alphaherpesvirus of chickens, causes a disease that is characterized by tumor formation, immunosuppression and neurological disorders. recent developments in chicken genomics have been applied to studies of mdv and have advanced our understanding of both the virus and the disease it causes. we have constructed and used microarrays to identify host genes that are up-regulated in chicken embryo fibroblasts infected with mdv as a first step to catalog th ... | 2007 | 17675881 |
| evidence for widespread epistatic interactions influencing marek's disease virus viremia levels in chicken. | marek's disease (md), a t cell lymphoma induced by the marek's disease virus (mdv), is the main chronic infectious disease concern threatening the poultry industry. enhancing genetic resistance to md in commercial poultry is an attractive method to augment md vaccines, which is currently the control method of choice. in order to implement this control strategy through marker-assisted selection (mas), it is necessary to identify quantitative trait loci (qtl) or genes that influence md incidence. ... | 2007 | 17675873 |
| horizontal transmission of marek's disease virus requires us2, the ul13 protein kinase, and gc. | marek's disease virus (mdv) causes a general malaise in chickens that is mostly characterized by the development of lymphoblastoid tumors in multiple organs. the use of bacterial artificial chromosomes (bacs) for cloning and manipulation of the mdv genome has facilitated characterization of specific genes and genomic regions. the development of most mdv bacs, including prb-1b-5, derived from a very virulent mdv strain, involved replacement of the us2 gene with mini-f vector sequences. however, w ... | 2007 | 17634222 |
| quantitative profiling of the shedding rate of the three marek's disease virus (mdv) serotypes reveals that challenge with virulent mdv markedly increases shedding of vaccinal viruses. | the shedding profile of marek's disease virus serotype 1 (mdv1, virulent), serotype 2 (mdv2, vaccinal) and herpesvirus of turkeys (hvt, vaccinal) in commercial broiler chickens was determined by measuring the daily rate of production of feather dander from chickens housed in isolators and by quantifying the viral load of each of these serotypes in the dander using quantitative real-time pcr (qpcr). mdv1 and hvt viruses were detectable in dander filtered from isolator exhaust air from day 7 and m ... | 2007 | 17622613 |
| identification and characterization of a novel spliced form of the meq transcript in lymphoblastoid cell lines derived from marek's disease tumours. | in tumour cell lines established from marek's disease (md) lymphomas l-meq is consistently expressed. it contains a 180 bp insertion encoding additional copies of the proline-rich repeat in the meq open reading frame and its product may contribute to the maintenance of md virus (mdv) latency. in this study, we identified a novel spliced form of the meq transcript in md-derived lymphoblastoid cell lines and in mdv-infected cells. this transcript, termed deltameq, encodes an n-terminal 98 aa of th ... | 2007 | 17622612 |
| marek's disease virus unique genes pp38 and pp24 are essential for transactivating the bi-directional promoters for the 1.8 kb mrna transcripts. | the pp38 and pp24 genes of marek's diseases virus (mdv) share the same promoter, which controls the transcription of pp38 or pp24 and a 1.8-kb mrna bi-directionally. to understand the trans-activating activity of pp38 and pp24 on the bi-directional promoter, both genes were cloned into pcdna-3 or pbudce4.1 vectors either singly or in combination. these plasmids were expressed in transfected chicken embryonic fibroblast (cef) cells. chloramphenicol acetyltransferase (cat) activity expressed under ... | 2007 | 17619133 |
| marek's disease virus research in the post-sequencing era: new tools for the study of gene functions and virus-host interactions. | despite the fact that the causative agent of marek's disease was described more than 30 years ago, and that subsequently many classical biological studies have been carried out on the marek's disease virus (mdv), detailed analysis of its gene functions has been hampered by lack of suitable research tools. information on the primary structure of mdv-1 and its serologically related viruses, mdv-2 and herpesvirus of turkeys, is now available. this review focuses on the introduction of the modern an ... | 2003 | 17585455 |
| phylogeny and recombination history of gallid herpesvirus 2 (marek's disease virus) genomes. | phylogenetic analyses based on concatenated amino acid sequences from orthologous loci from eight genomes of alpha herpesviruses infecting birds provided strong support for the following hypotheses: (1) gallid hv3 is a sister taxon to gallid hv2 but gallid hv1 is not closely related to the other two chicken herpesviruses; (2) meleagrid hv1 is closer to both gallid hv2 and gallid hv3 than is gallid hv1; (3) within gallid hv2, the virulent ga genome forms an outgroup to both the avirulent cvi988 g ... | 2007 | 17566585 |
| sequence determination of variable regions within the genomes of gallid herpesvirus-2 pathotypes. | comparative genomic studies of attenuated and virulent strains of gallid herpesvirus 2 (gahv-2) have identified 6 regions of sequence variability. these regions include the open reading frames (orfs) encoding ul36 and ul49 and regions devoid of large orfs (132-bp repeats, a-like sequences and the junctions flanking the unique short region). our data indicate that the carboxyl terminus of ul36 contains regions of heterogeneity that are unique to cvi988-derived attenuated strains. a deletion of th ... | 2007 | 17557133 |
| prevalence and molecular characterization of meq in feather follicular epithelial cells of korean broiler chickens. | marek's disease (md) is a highly contagious lymphoproliferative disease of chickens. meq is the relevant oncogene and four isoforms, long (l)-meq, meq, short (s)-meq and very short (vs)-meq, have been identified. although md is important in the poultry industry, the prevalence and molecular properties of korean md virus (mdv) among broiler chickens remain unclear. therefore, we characterized meq in pooled feather tips sampled at 3- and 5-week-old chickens from 21 unvaccinated and 22 vaccinated b ... | 2007 | 17516161 |
| extended gene map reveals tripartite motif, c-type lectin, and ig superfamily type genes within a subregion of the chicken mhc-b affecting infectious disease. | mhc haplotypes have a remarkable influence on whether tumors form following infection of chickens with oncogenic marek's disease herpesvirus. although resistance to tumor formation has been mapped to a subregion of the chicken mhc-b region, the gene or genes responsible have not been identified. a full gene map of the subregion has been lacking. we have expanded the mhc-b region gene map beyond the 92-kb core previously reported for another haplotype revealing the presence of 46 genes within 242 ... | 2007 | 17513765 |
| a full ul13 open reading frame in marek's disease virus (mdv) is dispensable for tumor formation and feather follicle tropism and cannot restore horizontal virus transmission of rrb-1b in vivo. | marek's disease virus (mdv) is an oncogenic alphaherpesvirus that is highly contagious in poultry. recombinant rb-1b (rrb-1b) reconstituted from an infectious genome cloned as a bacterial artificial chromosome (bac) is unable to spread horizontally, quite in contrast to parental rb-1b. this finding suggests the presence of one or several mutations in cloned relative to parental viral dna. sequence analyses of the prb-1b bacmid identified a one-nucleotide insertion in the ul13 orthologous gene th ... | 2007 | 17506972 |
| detection of the virulent marek's disease virus genome from feather tips of wild geese in japan and the far east region of russia. | marek's disease (md) virus (mdv) is known to cause malignant lymphomas in chickens. in 2001, we first reported an md case in a white-fronted goose (anser albifrons) in japan. therefore, the prevalence of mdv in the wild geese was surveyed by nested pcr using feather-tip samples in japan and the far east region of russia, breeding habitats of geese migrating to japan. mdv was detected in about 30% of analyzed white-fronted geese. furthermore, by nucleotide sequence analysis, we confirmed that thi ... | 2007 | 17497232 |
| evaluation of marek's disease field isolates by the "best fit" pathotyping assay. | although determination of the pathotype is central to the study of marek's disease (md) field isolates, methods are not standardized and results from different laboratories may not compare well with the original avian disease and oncology laboratory assay. this study was designed to investigate the validity of the "best fit" pathotyping assay, a simplified method recently described for testing of field isolates of md virus (mdv). twenty serotype 1 mdv strains were isolated from 12 breeder and co ... | 2007 | 17479374 |
| route of challenge is critical in determining the clinical outcome of infection with a very virulent oncogenic herpesvirus, marek's disease virus. | the majority of experimental studies examining marek's disease virus infection have used parenteral injection of cell-associated virus. the aim of this study was to examine whether the route of entry of virus was critical in determining the outcome of infection. susceptible (l7) and resistant (l6) white leghorn chickens were infected with a very virulent marek's disease virus, rb1b, by either the intra-abdominal or intra-tracheal route. birds infected by the intra-tracheal route had earlier, hig ... | 2007 | 17479368 |
| ovotransferrin expression and release by chicken cell lines infected with marek's disease virus. | mammals posses both serum transferrin and lactoferrin, whose functions are taken over in birds by ovotransferrin, displaying both iron transport and antibacterial activities. ovotransferrin also exerts antiviral activity towards marek's disease virus, an avian member of the herpes family of viruses. this virus infects lymphoid organs and induces the transcription of ovotransferrin in infected chicken embryo fibroblasts. however, it has not yet been established whether ovotransferrin gene transcr ... | 2007 | 17464355 |
| marek's disease virus type 2 (mdv-2)-encoded micrornas show no sequence conservation with those encoded by mdv-1. | micrornas (mirnas) are increasingly being recognized as major regulators of gene expression in many organisms, including viruses. among viruses, members of the family herpesviridae account for the majority of the currently known virus-encoded mirnas. the highly oncogenic marek's disease virus type 1 (mdv-1), an avian herpesvirus, has recently been shown to encode eight mirnas clustered in the meq and lat regions of the viral genome. the genus mardivirus, to which mdv-1 belongs, also includes the ... | 2007 | 17459919 |
| expression and intercellular trafficking of the vp22 protein of cvi988/rispens vaccine strain of marek's disease virus. | the viral protein 22 (vp22) in the tegument of marek's disease virus serotype 1 (mdv-1) plays an important role in cell-to-cell spread and viral propagation. antiserum against the carboxyl terminus of vp22 was prepared by immunizing mice with recombinant vp22 expressed in e. coli, and used to investigate its expression in chicken embryo fibroblast (cef) cells infected with different mdv-1 strains. at an infection dose of pfu=50, intercellular trafficking of the vp22 into the nuclei of the surrou ... | 2007 | 17393086 |
| sequential autoprocessing of marek's disease herpesvirus protease differs from that of other herpesviruses. | herpesviruses encode a unique serine protease essential for viral capsid maturation. this protease undergoes autoprocessing at two sites, r and m, at the consensus sequence (v, l, i)(p3)-x(p2)-a(p1)/s(p1') (where x is a polar amino acid). we observed complete autoprocessing at the r and m sites of marek's disease virus (mdv) protease following production of the polyprotein in escherichia coli. site-directed mutagenesis confirmed the predicted sequence of the r and m sites, with the m site sequen ... | 2007 | 17376905 |
| comparative full-length sequence analysis of oncogenic and vaccine (rispens) strains of marek's disease virus. | the complete dna sequence of the marek's disease virus serotype 1 vaccine strain cvi988 was determined and consists of 178 311 bp with an overall gene organization identical to that of the oncogenic strains. in examining open reading frames (orfs), nine differ between vaccine and oncogenic strains. a 177 bp insertion was identified in the overlapping genes encoding the meq, rlorf6 and 23 kda proteins of cvi988. three orfs are predicted to encode truncated proteins. one, designated 49.1, overlaps ... | 2007 | 17374751 |