Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| marek's disease virus infection in the brain: virus replication, cellular infiltration, and major histocompatibility complex antigen expression. | marek's disease virus (mdv) infection in the brain was studied chronologically after inoculating 3-week-old chickens of two genetic lines with two strains of serotype i mdv representing two pathotypes (v and vv+). viral replication in the brain was strongly associated with the development of lesions. three viral antigens (pp38, gb, and meq) were detected in the brain of infected chickens. marked differences between v and vv+ pathotypes of mdv were identified for level of virus replication, time ... | 2001 | 11572556 |
| lack of contact transmission of recombinant marek's disease virus type 1 expressing the fusion protein of newcastle disease virus. | to clarify the level of excretion of a recombinant marek's disease virus type 1 (rmdv1) that confers good protection in chickens against both marek's and newcastle diseases, even in the presence of maternal antibodies, contact transmission tests were conducted. naïve chickens kept in the same cage or room with chickens inoculated with rmdv1 did not produce antibodies against mdv1 or the fusion protein of newcastle disease virus. moreover, the rmdv1 was not isolated from the dander of chickens in ... | 2001 | 11672913 |
| glycoproteins e and i of marek's disease virus serotype 1 are essential for virus growth in cultured cells. | the role of glycoprotein e (ge) and gi of marek's disease virus serotype 1 (mdv-1) for growth in cultured cells was investigated. mdv-1 mutants lacking either ge (20deltage), gi (20deltagi), or both ge and gi (20deltagei) were constructed by rece/t-mediated mutagenesis of a recently established infectious bacterial artificial chromosome (bac) clone of mdv-1 (d. schumacher, b. k. tischer, w. fuchs, and n. osterrieder, j. virol. 74:11088-11098, 2000). deletion of either ge or gi, which form a comp ... | 2001 | 11689611 |
| increased virulence of marek's disease virus type 1 vaccine strain cv1988 after adaptation to qt35 cells. | cvi988/rispens strain of marek's disease virus type i (mdv-1) is widely used as efficient vaccine to control marek's disease (md) in chicken flocks. similarly to other live md vaccine viruses it is propagated in freshly prepared chicken embryo fibroblasts (cef). in this study, mdv-1 cvi988/rispens strain was adapted to qt35 cells. the adapted virus, designated qt-cvi, exhibited similar cytopathic effect (cpe) in vitro to that of parental virus propagated in cee in contrast, qt-cvi induced md sym ... | 2001 | 11719980 |
| functional characterization of marek's disease virus (mdv) origin-binding protein (obp): analysis of its origin-binding properties. | in previous studies, we identified a marek's disease virus (mdv) origin-binding protein (obp) gene that is highly homologous to the herpes simplex virus type 1 ul9 gene that encodes an obp and functions as an initiator protein for viral dna replication. in this study, a protein of 95 kda was produced in coupled in vitro transcription-translation reaction with the plasmid containing the wild type mdv obp gene. the in vitro synthesized protein was detected by immunoprecipitation with a penta-histi ... | 2001 | 11724278 |
| a strategy to identify positional candidate genes conferring marek's disease resistance by integrating dna microarrays and genetic mapping. | marker-assisted selection (mas) to enhance genetic resistance to marek's disease (md), a herpesvirus-induced t cell cancer in chicken, is an attractive alternative to augment control with vaccines. our earlier studies indicate that there are many quantitative trait loci (qtl) containing one or more genes that confer genetic resistance to md. unfortunately, it is difficult to sufficiently resolve these qtl to identify the causative gene and generate tightly linked markers. one possible solution i ... | 2001 | 11736805 |
| [the clone and comparison of very virulent plus marek's disease virus(vv+ dmv)648 strain glycoprotein e(ge) gene]. | the glycoprotein e(ge) gene of very virulent plus marek's disease (vv+ mdv) 648 strain was amplified by polymerase chain reaction (pcr) and cloned into puc18 vector. the ge sequence was determined and analysed. the whole length of 648 strain ge gene is 1494 base pairs. the protein encoded by ge gene has several features characteristic of a membrane-associated glycoprotein. it contains eight potential glycosylation sites, a markedly hydrophobic region at the n terminus that could function as a si ... | 2001 | 12549019 |
| [studies on in vitro expression for gi gene of marek's disease in e. coli by pgex vector]. | glycoprotein i gene(gi) was amplified from genomic dna of marek's disease virus (mdv) 648 strain by polymerase chain reaction(pcr). pcr product was cloned into pgex-6p-1 according to the right open reading frame(orf). the expression of gst-gi fusion protein was studied in detail on many factors including temperature, timing and iptg. the curve for od600 and the growing time of the recombinant bacteria is also established., which is helpful to find the optimal inducing time. gst-gi fusion protein ... | 2001 | 12552804 |
| induction of host gene expression following infection of chicken embryo fibroblasts with oncogenic marek's disease virus. | microarrays containing 1,126 nonredundant cdnas selected from a chicken activated t-cell expressed sequence tag database (http://chickest.udel.edu) were used to examine changes in host cell gene expression that accompany infection of chicken embryo fibroblasts (cef) with marek's disease virus (mdv). host genes that were reproducibly induced by infection of cef with the oncogenic rb1b strain of mdv included macrophage inflammatory protein, interferon response factor 1, interferon-inducible protei ... | 2001 | 11119623 |
| detection of avian oncogenic marek's disease herpesvirus dna in human sera. | the avian herpesvirus marek's disease virus (mdv) has a worldwide distribution and is responsible for t-lymphoma in chickens. the question as to whether mdv poses a public health hazard to humans was first raised when the virus was isolated in 1967. however, no irrefutable results have been obtained in immunological and virological studies. we used a nested-pcr to detect mdv dna in human serum samples. a total of 202 serum samples from individuals exposed and not exposed to poultry was tested by ... | 2001 | 11125176 |
| the genome of turkey herpesvirus. | here we present the first complete genomic sequence of marek's disease virus serotype 3 (mdv3), also known as turkey herpesvirus (hvt). the 159,160-bp genome encodes an estimated 99 putative proteins and resembles alphaherpesviruses in genomic organization and gene content. hvt is very similar to mdv1 and mdv2 within the unique long (ul) and unique short (us) genomic regions, where homologous genes share a high degree of colinearity and their proteins share a high level of amino acid identity. w ... | 2001 | 11134310 |
| transcriptional analysis of marek's disease virus glycoprotein d, i, and e genes: gd expression is undetectable in cell culture. | the various alphaherpesviruses, including marek's disease virus (mdv), have both common and unique features of gene content and expression. the entire mdv u(s) region has been sequenced in our laboratory (p. brunovskis and l. f. velicar, virology 206:324-338, 1995). genes encoding the mdv glycoprotein d (gd), glycoprotein i (gi), and glycoprotein e (ge) homologs have been found in this region, although no gg homolog was found. in this work, transcription of the tandem mdv gd, gi, and ge genes wa ... | 2001 | 11160711 |
| the use of serotype 1- and serotype 3-specific polymerase chain reaction for the detection of marek's disease virus in chickens. | a serotype 1- and serotype 3-specific detection of marek's disease virus (mdv) by polymerase chain reaction (pcr) was developed. the sensitivity of the method when applied to cell culture grown virus was comparable with that of cultivation. the method was applied to various tissue samples from chickens experimentally inoculated with serotype 1 or serotype 3 mdv.the serotype 1 strains cvi988 and rb-1b could be detected in feather follicle epithelium up to 56 and 84 days post-inoculation (p.i.), r ... | 2001 | 19184906 |
| differential attenuation of the induction by marek's disease virus of transient paralysis and persistent neurological disease: a model for pathogenesis studies. | since different biological characteristics of marek's disease virus (mdv) are attenuated at different passage levels in cell culture, an analysis of attenuation times provides, in theory, a model for establishing the presence or absence of relationships between characteristics, thus providing a basis to link them to genetic changes in the causative virus. we have used this model to better understand the pathogenesis of the central nervous system infection as well as to evaluate the relationship ... | 2001 | 19184925 |
| influence of vaccine deposition site on post-vaccinal viraemia and vaccine efficacy in broiler chickens following in ovo vaccination against marek's disease. | in ovo vaccination against marek's disease is a widely used technology in the broiler industry.a series of experiments was carried out to determine the site of vaccine deposition in the egg during automated in ovo vaccination, and the effect of vaccine deposition site and dose on vaccine responses following vaccination with cell-associated herpesvirus of turkeys in commercial broiler chickens. vaccine deposition site following automated in ovo vaccination was principally influenced by the age of ... | 2001 | 19184942 |
| innovation and discovery: the application of nucleic acid-based technology to avian virus detection and characterization. | polymerase chain reaction (pcr)-based approaches to the detection, differentiation and characterization of avian pathogens continue to be developed and refined. the pcrs, or reverse transcriptase-pcrs, may be general, designed to detect all or most variants of a pathogen, or to be serotype, genotype or pathotype specific. progress is being made with respect to making nucleic acid approaches more suitable for use in diagnostic laboratories. robotic workstations are now available for extraction of ... | 2001 | 19184952 |
| marek's disease in broiler chickens: effect of route of infection and herpesvirus of turkey-vaccination status on detection of virus from blood or spleen by polymerase chain reaction, and on weights of birds, bursa and spleen. | the polymerase chain reaction (pcr) has recently emerged as an additional tool for the monitoring and diagnosis of marek's disease. we investigated a number of factors that may influence the interpretation of pcr results in commercial broiler chickens including the effects of route of infection and herpesvirus of turkeys (hvt)-vaccination status. we also investigated the suitability of peripheral blood lymphocytes (pbl) and spleen as tissues for marek's disease virus (mdv) detection. hvt-vaccina ... | 2001 | 19184956 |
| effect of cryptosporidium baileyi in specific pathogen free chickens vaccinated (cvi988/rispens) and challenged with hprs-16 strain of marek's. | this study was performed to examine the effect of marek's disease virus (mdv) serotype 1 vaccine (cvi988/rispens) on the pathogenicity of cryptosporidium baileyi , and to determine whether c. baileyi infection could prevent the development of vaccinal marek's disease (md) immunity in specific pathogen free (spf) chickens. sixty-eight spf homozygous b13 white leghorn chickens were divided into seven groups. c. baileyi was orally administered at 5 days of age (day 4) in chickens infected with risp ... | 2000 | 19184860 |
| the simple chicken major histocompatibility complex: life and death in the face of pathogens and vaccines. | in contrast to the major histocompatibility complex (mhc) of well-studied mammals such as humans and mice, the particular haplotype of the b-f/b-l region of the chicken b locus determines life and death in response to certain infectious pathogens as well as to certain vaccines. we found that the b-f/b-l region is much smaller and simpler than the typical mammalian mhc, with an important difference being the expression of a single class i gene at a high level of rna and protein. the peptide-bindi ... | 2000 | 11186309 |
| serological monitoring on layer farms with specific pathogen-free chickens. | to monitor the existence of avian pathogens in laying chicken flocks, specific pathogen-free (spf) chickens were introduced into two layer farms and reared with laying hens for 12 months. spf chickens were bled several times after their introduction and examined for their sero-conversion to avian pathogens. as a result, antibodies to eight or ten kinds of pathogens were detected in spf chickens on each farm. antibodies to infectious bronchitis virus (ibv), avian nephritis virus, mycoplasma galli ... | 2000 | 11193353 |
| development of a quantitative-competitive polymerase chain reaction assay for serotype 1 marek's disease virus. | we have developed a quantitative-competitive (qc) polymerase chain reaction (pcr) for the detection of marek's disease virus (mdv) dna. the assay utilizes a competitor dna that differs from the viral dna of interest by having a small insertion. the competitor dna acts as an internal standard for the estimation of viral dna in an unknown sample. the amount of viral dna in a sample is quantitated by coamplification in the presence of a known amount of competitor dna. the same pcr primers that ampl ... | 2000 | 11195630 |
| interaction of marek's disease virus and cryptosporidium baileyi in experimentally infected chickens. | histocompatible b13/b13 white specific-pathogen-free leghorn chickens were used to investigate the effect of coinfection with cryptosporidium baileyi and the hprs 16 strain of marek's disease virus (mdv) in chickens and to assess the pathogenicity of c. baileyi when mdv is given before or after the parasite. groups of chickens concurrently infected with c. baileyi orally inoculated at day (d)4 and mdv inoculated at hatching (c4m0 group) or at d8 (c4m8 group) were compared with relevant control g ... | 2000 | 11195631 |
| viral pathogenesis in chicken embryos and tumor induction in chickens after in ovo exposure to serotype 1 marek's disease virus. | we examined the susceptibility of late-stage chicken embryos to infection with oncogenic serotype 1 marek's disease virus (mdv 1). intravenous inoculation of mdv 1 at embryonic day (ed) 16 resulted in significant replication of the virus in embryonic tissues. within 5 days of virus exposure, pp38 viral antigen (pp38) was detected in embryonic bursae and mdv 1 was isolated by plaque assay from the spleens, thymuses, and bursae of embryos. the pathogenesis of mdv 1 after intravenous inoculation at ... | 2000 | 11195638 |
| antibody titers to infectious bursal disease virus in broiler chicks after vaccination at one day of age with infectious bursal disease virus and marek's disease virus. | the effect of day-of-age vaccination with infectious bursal disease virus (ibdv) alone or in combination with marek's disease virus (mdv) in broiler chicks was investigated. one-day-old commercial broiler progeny obtained from ibdv-immunized breeder flocks were vaccinated subcutaneously according to the manufacturer's directions with live-attenuated commercially available vaccines as follows: ibdv alone, mdv alone, ibdv + mdv, and unvaccinated control. ibdv was not detected after vaccination by ... | 2000 | 11195642 |
| marek's disease: an update on oncogenic mechanisms and control. | marek's disease (md) is a common lymphoproliferative disease of poultry caused by a highly contagious and oncogenic herpesvirus. in spite of the widespread use of highly effective md vaccines, recently there have been worrying trends in the evolution of md virus pathotypes towards greater virulence. in the last few years, there has been significant progress in determining the molecular structure of md virus and several genes that map within the repeat regions of the virus, such as bam hi-h famil ... | 2000 | 10924389 |
| the genome of a very virulent marek's disease virus. | here we present the first complete genomic sequence, with analysis, of a very virulent strain of marek's disease virus serotype 1 (mdv1), md5. the genome is 177,874 bp and is predicted to encode 103 proteins. mdv1 is colinear with the prototypic alphaherpesvirus herpes simplex virus type 1 (hsv-1) within the unique long (ul) region, and it is most similar at the amino acid level to mdv2, herpesvirus of turkeys (hvt), and nonavian herpesviruses equine herpesviruses 1 and 4. mdv1 encodes 55 hsv-1 ... | 2000 | 10933706 |
| neoplastic diseases: marek's disease, avian leukosis and reticuloendotheliosis. | the commercially important neoplastic diseases of poultry are marek's disease, which is caused by a herpesvirus, and the avian leukoses and reticuloendotheliosis, which are caused by retroviruses. these diseases are responsible for economic loss due to both mortality and depressed performance. marek's disease virus (mdv) and avian leukosis viruses (alvs) are prevalent throughout the world, and new strains which arise in particular locations may spread across borders, thereby undermining national ... | 2000 | 10935279 |
| marek's disease virus (mdv) homologues of herpes simplex virus type 1 ul49 (vp22) and ul48 (vp16) genes: high-level expression and characterization of mdv-1 vp22 and vp16. | genes ul49 and ul48 of marek's disease virus 1 (mdv-1) strain rb1b, encoding the respective homologues of herpes simplex virus type 1 (hsv-1) genes vp22 and vp16, were cloned into a baculovirus vector. seven anti-vp22 mabs and one anti-vp16 mab were generated and used to identify the tegument proteins in cells infected lytically with mdv-1. the two genes are known to be transcribed as a single bicistronic transcript, and the detection of only one of the two proteins (vp22) in msb-1 lymphoma and ... | 2000 | 10950980 |
| protective immunity to infectious bronchitis in broilers vaccinated against marek's disease either in ovo or at hatch and against infectious bronchitis at hatch. | two experiments were conducted using commercial broiler chickens to determine if marek's disease (md) vaccines hvt/sb-1 and hvt plus cvi-988 given either in ovo or at hatch adversely affected the efficacy of infectious bronchitis (ib) vaccines (ark and mass serotypes) given by eyedrop on the day of hatch. nonvaccinated negative controls and controls that received only ib vaccines were included in each study. birds were challenged with either infectious bronchitis virus (ibv) mass-41 or ibv ark-9 ... | 2000 | 11007000 |
| marek's disease herpesvirus transforming protein meq: a c-jun analogue with an alternative life style. | in order to adapt to and to cope with an often hostile host environment, many viruses have evolved to encode products that are homologous to cellular proteins. these proteins exploit the existing host machinery and allow viruses to readily integrate into the host functional network. as a result, viruses are able to maneuver their journey seemingly effortlessly inside the host cell to achieve ultimate survival. such molecular mimicries sometime go overboard, allowing viruses to overtake the cellu ... | 2000 | 11022789 |
| transactivation of latent marek's disease herpesvirus genes in qt35, a quail fibroblast cell line, by herpesvirus of turkeys. | the qt35 cell line was established from a methylcholanthrene-induced tumor in japanese quail (coturnix coturnix japonica) (c. moscovici, m. g. moscovici, h. jimenez, m. m. lai, m. j. hayman, and p. k. vogt, cell 11:95-103, 1977). two independently maintained sublines of qt35 were found to be positive for marek's disease virus (mdv)-like genes by southern blotting and pcr assays. sequence analysis of fragments of the icp4, icp22, icp27, vp16, meq, pp14, pp38, open reading frame (orf) l1, and glyc ... | 2000 | 11024146 |
| nitric oxide inhibits marek's disease virus replication but is not the single decisive factor in interferon-gamma-mediated viral inhibition. | the purpose of this study was to determine to what extent nitric oxide (no) may play a role in the antiviral-mediated effect of chicken ifn-gamma against the marek's disease virus (mdv) rb-1b. no-generating compounds s-nitroso-n-acetylpenicillamine (snap) and 3-morpholino-sydononimine (sin-1) strongly inhibited rb-1b replication in chicken embryo fibroblasts (85%) in a dose-dependent manner. the addition of superoxide dismutase (sod) did not alter the inhibitory effect of sin-1, which is also kn ... | 2000 | 11062036 |
| reconstitution of marek's disease virus serotype 1 (mdv-1) from dna cloned as a bacterial artificial chromosome and characterization of a glycoprotein b-negative mdv-1 mutant. | the complete genome of marek's disease virus serotype 1 (mdv-1) strain 584ap80c was cloned in escherichia coli as a bacterial artificial chromosome (bac). bac vector sequences were introduced into the u(s)2 locus of the mdv-1 genome by homologous recombination. viral dna containing the bac vector was used to transform escherichia coli strain dh10b, and several colonies harboring the complete mdv-1 genome as an f plasmid (mdv-1 bacs) were identified. dna from various mdv-1 bacs was transfected in ... | 2000 | 11070004 |
| application of representational difference analysis to genomic fragments of marek's disease virus. | a rapid and simple method for isolation of dna fragments of marek's disease virus (mdv) based on representational difference analysis (rda) was developed. multiple viral dna fragments, the sizes of which were restricted to 0.3 to 3.5 kbp, were simultaneously amplified after subtraction of chicken dna from bamhi-, bglii-, ecori-, hindiii-, or xhoi-digested dna fragments of mdv-infected cells. nucleotide sequence of two rda-derived fragments coincided with the sequence determined from direct seque ... | 2000 | 11101556 |
| development of an effective polyvalent vaccine against both marek's and newcastle diseases based on recombinant marek's disease virus type 1 in commercial chickens with maternal antibodies. | an earlier report (m. sakaguchi et al., vaccine 16:472-479, 1998) showed that recombinant marek's disease virus type 1 (rmdv1) expressing the fusion (f) protein of newcastle disease virus (ndv-f) under the control of the simian virus 40 late promoter [rmdv1-us10l(f)] protected specific pathogen-free chickens from ndv challenge, but not commercial chickens with maternal antibodies against ndv and mdv1. in the present study, we constructed an improved polyvalent vaccine based on mdv1 against mdv a ... | 2000 | 10708438 |
| immunocytochemical techniques to investigate the pathogenesis of infectious micro-organisms and the concurrent immune response of the host. | for poultry as well as for mammalian species used for scientific research, many immunocytochemical techniques have been developed to investigate in detail the interaction between infectious micro-organisms and the nonspecific and specific immune systems of the host. in this review three techniques have been described with all technical details necessary to perform them correctly: (1) single immunocytochemical staining to detect the infectious micro-organisms in situ at their site of infection, ( ... | 2000 | 10717284 |
| specific and nonspecific immune responses to marek's disease virus. | marek's disease (md) virus (mdv) has provided an important model to study immune responses against a lymphoma-inducing herpesvirus in its natural host. infection in chickens starts with a lytic infection in b cells, followed by a latent infection in t cells and, in susceptible birds, t cell lymphomas develop. non-specific and specific immune responses are important for the control of virus infection and subsequent tumor development. interferon-gamma and nitric oxide are important for the control ... | 2000 | 10717288 |
| inhibitory effects of nitric oxide and gamma interferon on in vitro and in vivo replication of marek's disease virus. | the replication of marek's disease herpesvirus (mdv) and herpesvirus of turkeys (hvt) in chicken embryo fibroblast (cef) cultures was inhibited by the addition of s-nitroso-n-acetylpenicillamine, a nitric oxide (no)-generating compound, in a dose-dependent manner. treatment of cef culture, prepared from 11-day-old embryos, with recombinant chicken gamma interferon (rchifn-gamma) and lipopolysaccharide (lps) resulted in production of no which was suppressed by the addition of n(g)-monomethyl l-ar ... | 2000 | 10729136 |
| the genome of fowlpox virus. | here we present the genomic sequence, with analysis, of a pathogenic fowlpox virus (fpv). the 288-kbp fpv genome consists of a central coding region bounded by identical 9.5-kbp inverted terminal repeats and contains 260 open reading frames, of which 101 exhibit similarity to genes of known function. comparison of the fpv genome with those of other chordopoxviruses (chpvs) revealed 65 conserved gene homologues, encoding proteins involved in transcription and mrna biogenesis, nucleotide metabolis ... | 2000 | 10729156 |
| dual-viral vector approach induced strong and long-lasting protective immunity against very virulent infectious bursal disease virus. | to induce strong protective immunity against very virulent infectious bursal disease virus (vvibdv) in chickens, two viral vector systems, marek's disease and fowlpox viruses expressing the vvibdv host-protective antigen vp2 (rmdv, rfpv), were used. most of chickens vaccinated with the rfpv or rmdv alone, or vaccinated simultaneously with both at their hatch (rmdv-rfpv(1d)), were protected against developing clinical signs and mortality; however, only zero to 14% of the chickens were protected a ... | 2000 | 10753704 |
| difference in the meq gene between oncogenic and attenuated strains of marek's disease virus serotype 1. | serotype 1 strains of marek's disease virus (mdv1), except attenuated vaccine strains, are known to cause lymphomas in visceral organs of infected chickens. to know additional genetic differences between oncogenic and nononcogenic mdv1, polymerase chain reaction (pcr) was performed to amplify the meq gene of the viral genome. in addition to the 1,062-bp band including the native meq open reading frame (orf), a 1.2-kb band was amplified from the dna sample prepared from chick embryo fibroblast in ... | 2000 | 10770601 |
| expression of cytokine genes in marek's disease virus-infected chickens and chicken embryo fibroblast cultures. | the role of cytokines in the pathogenesis and immunity of marek's disease (md), a herpesvirus-induced t-cell lymphoma in chickens, is poorly understood. two different experiments were used to examine the potential role of particular cytokines in the pathogenesis and immune responses of md. first, chicken embryo fibroblasts (cef) were stimulated with lipopolysaccharide (lps) and/or recombinant chicken interferon-gamma (rchifn-gamma) and used to develop techniques for examining transcription of if ... | 2000 | 10809961 |
| identification and expression of a mycoplasma gallisepticum surface antigen recognized by a monoclonal antibody capable of inhibiting both growth and metabolism. | in order to identify antigenic proteins of mycoplasma gallisepticum, monoclonal antibodies (mabs) against virulent m. gallisepticum r strain were produced in mice. mab 35a6 was selected for its abilities to inhibit both growth and metabolism of m. gallisepticum in vitro. the mab recognized a membrane protein with an apparent molecular mass of 120 kda. the corresponding gene, designated the mgc3 gene, was cloned from an m. gallisepticum genomic dna expression library and sequenced. the mgc3 gene ... | 2000 | 10816462 |
| the complete unique long sequence and the overall genomic organization of the ga strain of marek's disease virus. | we have determined the dna sequence of the unique long (ul) region and the repeat long (rl) region in the genome of serotype 1 ga strain of marek's disease virus (mdv), a member of the alpha-herpesvirus family. with this information, the complete nucleotide sequence of ga-mdv is now known. the entire ga-mdv genome is predicted to be about 174 kbp in size, with an organization of trl-ul-irl-irs-us-trs, typical of a alpha-herpesvirus. the ul sequence contains 113,508 bp and has a base composition ... | 2000 | 10823954 |
| development of the hot spot-combined pcr assay for detection of retroviral insertions into marek's disease virus. | a two-step pcr, the hot spot-combined pcr assay, was developed for the identification and characterization of recombinant viruses in marek's disease (herpes) and retrovirus co-infections. in the first pcr the herpesvirus genomic fragment, that was recognized in previous studies as a hot spot site for retroviral integration was amplified [reviewed in bronovskis, p., kung, h.-j., 1996. retrotransposition and herpesvirus evolution. virus genes 11, 259-270]. the products served for a second amplific ... | 1999 | 10894628 |
| analysis of transcriptional and translational activities of marek's disease (md) virus genes in md central nervous system lesions in chickens. | the expression of marek's disease virus (mdv) gene products and transcripts was observed in tissues obtained from the central nervous system (cns) of chickens experimentally infected with a very virulent strain (md/5) of mdv. many cells antigen-positive for mdv early gene products, but not for late gene products, were detected immunohistochemically in the necrotizing lymphomatous lesions. the positive signals were found only in necrotic or degenerated neoplastic lymphoblasts. abundant transcript ... | 1999 | 16147548 |
| [cloning of glycoprotein b gene from strain rispens of marek's disease virus and construction of recombinant fowlpox virus]. | purified dnas from chicken embryo fibroblast (cef) cultures infected with mdv strain rispens were used as templates. specific fragment with the size of about 2.9 kb was successfully amplified through polymerase chain reaction(pcr) and identified to be gb gene of mdv by dot blot hybridization with a digoxigenin-labelled mdv gb specific oligonucleotide probe. the gb gene from strain rispens was cloned into puc19 and fpv insertion vector pfg1175-1 to construct plasmid pmgb and pfgbr1775-1 respectiv ... | 1999 | 12555423 |
| proceedings of the 2nd international workshop on molecular pathogenesis of marek's disease. slovak republic, august 8-11, 1998. | 1999 | 10819696 | |
| recombinant marek's disease virus (mdv)-derived lymphoblastoid cell lines: regulation of a marker gene within the context of the mdv genome. | marek's disease is a herpesvirus (marek's disease virus [mdv])-induced pathology of chickens characterized by paralysis and the rapid appearance of t-cell lymphomas. lymphoblastoid cell lines (lbcls) derived from mdv-induced tumors have served as models of mdv latency and transformation. we have recently reported the construction of mutant mdvs having a deletion (m. s. parcells et al., j. virol. 69:7888-7898, 1995) and an insertion (a. s. anderson et al., j. virol. 72:2548-2553, 1998) within the ... | 1999 | 9882341 |
| t-cell transformation by marek's disease virus. | marek's disease virus (mdv) is an avian herpesvirus that causes rapid development of t-cell lymphomas in chickens. the mdv genes currently thought to be involved in lymphomagenesis include a bzip transactivator that is homologous to fos and jun oncogenes but do not appear to have counterparts in other oncogenic herpesviruses. | 1999 | 10068994 |
| re-isolation of marek's disease virus from t cell subsets of vaccinated and non-vaccinated chickens. | to know the effect of marek's disease (md) vaccines, we analyzed the distribution of md virus (mdv) among t cell subsets from chickens vaccinated or non-vaccinated with md vaccine and subsequently challenged with a virulent mdv. the challenged mdv was reisolated preferentially from cd4+ t cells, and the average titers of challenged mdv rescued were significantly lower in vaccinated chickens compared to that of non-vaccinated chickens. in addition, it was also shown that different serotypes of md ... | 1999 | 10076508 |
| functional interactions between herpesvirus oncoprotein meq and cell cycle regulator cdk2. | marek's disease virus, an avian alphaherpesvirus, has been used as an excellent model to study herpesvirus oncogenesis. one of its potential oncogenes, meq, has been demonstrated to transform a rodent fibroblast cell line, rat-2, in vitro by inducing morphological transformation and anchorage- and serum-independent growth and by protecting cells from apoptosis induced by tumor necrosis factor alpha, c2-ceramide, uv irradiation, or serum deprivation. in this report, we show that there is a cell c ... | 1999 | 10196317 |
| gene arrangement and rna transcription of the bamhi fragments k and m2 within the non-oncogenic marek's disease virus serotype 2 unique long genome region. | we determined the nucleotide sequence of a 6593 bp fragment of the marek's disease virus serotype 2 (mdv2) unique long region located in the right part of genomic bamhi-m2 and the adjacent part of bamhi-k fragments. within this region five complete open reading frames (orfs) were identified whose deduced amino acid sequences exhibited homology to the ul53 (glycoprotein k), ul54 (immediate early regulatory protein icp27), and ul55 gene products of herpes simplex virus type 1 (hsv-1). homologue to ... | 1999 | 10225279 |
| protection of chickens against very virulent infectious bursal disease virus (ibdv) and marek's disease virus (mdv) with a recombinant mdv expressing ibdv vp2. | to develop a herpes virus vaccine that can induce immunity for an extended period, a recombinant marek's disease (md) virus (mdv) cvi-988 strain expressing infectious bursal disease virus (ibdv) host-protective antigen vp2 at the us2 site (rmdv) was developed under the control of an sv40 early promoter. chickens vaccinated with the rmdv showed no clinical signs and no mortality and 55% of the chickens were considered protected histopathologically after challenge with very virulent ibdv (vvibdv), ... | 1999 | 10329546 |
| antisense oligonucleotide complementary to the bamhi-h gene family of marek's disease virus induced growth arrest of mdcc-msb1 cells in the s-phase. | dna synthesis was effectively inhibited by antisense oligonucleotide a1 complementary to the bamhi-h gene family in marek's disease virus (mdv)-derived lymphoblastoid mdcc-msb1 cells. when a cell cycle distribution of a total cell population was analyzed by flow cytometry, the proportion of s-phase cells increased in the cell populations by treatment with oligonucleotide a1. approximately 60-70% of the cells appeared in the s phase for 24 and 36 hr of incubation in the presence of oligonucleotid ... | 1999 | 10342290 |
| identification and structure of the marek's disease virus serotype 2 glycoprotein m gene: comparison with glycoprotein m genes of herpesviridae family. | we determined the nucleotide sequence of a portion of bamhi-c fragment of marek's disease virus serotype 2 (mdv2) strain hprs24 which was suspected to contain the homologue of the herpes simplex virus type 1 (hsv-1) gene ul10, encoding glycoprotein m (gm). an open reading frame whose translation product exhibited significant similarities to hsv-1 gm protein and respective proteins of other herpesviruses of 37.5% and 45.5% to 31.8%, respectively, was identified. a number of distinct transcription ... | 1999 | 10379942 |
| genome analysis of marek's disease virus strain cvi-988: effect of cell culture passage on the inverted repeat regions. | the genomes of different derivatives of marek's disease virus (mdv) strain cvi-988, a low oncogenic isolate of a serotype 1 mdv, were analyzed by restriction enzyme analyses to detect whether alterations occurred after passages in cell culture. dna molecules of strain 988 isolated directly from blood cells contained mainly two copies of the 132-bp repeat sequence previously reported within bamh1-h and -d fragment as previously reported for more virulent mdv strains. although a minority of virus ... | 1999 | 10396630 |
| in ovo vaccination of specific-pathogen-free chickens with vaccines containing multiple agents. | we used in ovo technology to protect chickens against multiple diseases by inoculating vaccines containing mixtures of live viral agents. a single in ovo injection of a vaccine containing serotypes 1, 2, and 3 of marek's disease virus (mdv), a vaccine strain of serotype 1 infectious bursal disease virus (ibdv), and recombinant fowl pox vaccine with hn and f genes of newcastle disease virus (rfp-ndv) induced protection against virulent mdv, ibdv, newcastle disease virus, and fowl poxvirus. the mu ... | 1999 | 10396643 |
| electron microscopic and immunohistochemical localization of marek's disease (md) herpesvirus particles in md skin lymphomas. | skin lymphomas induced in 11 specific-pathogen-free chickens by inoculation at 1 day of age with marek's disease virus (mdv) were biopsied weekly and examined by electron microscopy and immunohistochemistry. in the sequentially biopsied lymphomas, immature mdv particles (abortive replication) were found only in the nuclei of necrotic lymphoblasts within necrotizing neoplasms. the necrotizing lymphomas were observed in two of the 11 experimental birds and were associated with prominent vascular e ... | 1999 | 10421098 |
| identification and dna sequence analysis of the marek's disease virus serotype 2 genes homologous to the herpes simplex virus type 1 ul20 and ul21. | we determined 3,135 bp of the nucleotide sequence located in an 8.5 kb ecori-e fragment in the unique long (ul) genome region of marek's disease virus serotype 2 (mdv2), and identified ul20 and ul21 homologous genes of herpes simplex virus type 1 (hsv-1). the ul20 and ul21 homologous genes of mdv2 are arranged colinearly with the prototype sequence of hsv-1. in addition, an open reading frame (mdv2 orf 273), which has been identified within the ul21 homologous gene of mdv2, has no apparent relat ... | 1999 | 10423678 |
| identification and sequence analysis of the marek's disease virus serotype 2 gene homologous to the herpes simplex virus type 1 ul52 protein. | the gene of marek's disease virus serotype 2 (mdv2) homologous to the ul52 gene of herpes simplex virus type 1 (hsv-1) was identified and characterized. the mdv2 ul52 homologous gene encodes 1,071 amino acids with a molecular weight of 118.7 kda, which includes putative metal-binding site and overlapping region with the ul53 homologous gene. although a putative polyadenylation signal sequence was found in the downstream of the mdv2 ul52 gene, a mdv2 ul52 dna probe reacted only with the polycistr ... | 1999 | 10423692 |
| response of embryonic chicken lymphocytes to in ovo exposure to lymphotropic viruses. | to examine effects of virus exposure on embryonic lymphoid organ structure, apoptosis, and lymphoid cell subpopulations. | 1999 | 10451200 |
| detection of new dna polymerase genes of known and potentially novel herpesviruses by pcr with degenerate and deoxyinosine-substituted primers. | a consensus primer pcr approach was used to (i) investigate the presence of herpesviruses in wild and zoo equids (zebra, wild ass, tapir) and to (ii) study the genetic relationship of the herpesvirus of pigeons (columbid herpesvirus 1) to other herpesvirus species. the pcr assay, based on degenerate primers targeting highly conserved regions of the dna polymerase gene of herpesviruses, was modified by using a mixture of degenerate and deoxyinosine-substituted primers. the applicability of the mo ... | 1999 | 10456789 |
| ultrastructural recognition of dendritic cells in the intimal lesions of aortas of chickens affected with marek's disease. | the present study was undertaken to determine whether dendritic cells contributed to the intimal abnormalities seen in the aortas of chickens infected with marek's disease. semithin sections were used to select aortic segments in which the intima was thickened by lymphocytic infiltrates. ultrathin sections were then examined. intermingled with lymphocytes within the intimal thickenings were cells with an appearance typical of dendritic cells including long processes and a unique tubulovesicular ... | 1999 | 10457604 |
| identification and sequence analysis of the marek's disease virus serotype 2 homologous genes of the herpes simplex virus type 1 ul25, ul26 and ul26.5 genes. | we identified and determined the nucleotide sequence of marek's disease virus serotype 2 (mdv2) ul25, ul26 and ul26.5 homologous genes of herpes simplex virus type 1 (hsv-1). the ul25, ul26 and ul26.5 genes of hsv-1 encode virion proteins (ul25 and ul26.5) and serine protease (ul26). the deduced amino acid sequences of the three proteins show a high degree of homology to counterparts of hsv-1. by northern blot analyses we found that four transcripts whose sizes are 4.9, 3.9, 2.0 and 1.3 kb are t ... | 1999 | 10458102 |
| occurrence of acute paralysis virus of the honey bee (apis mellifera) in a hungarian apiary infested with the parasitic mite varroa jacobsoni. | viruses of the honey bee have been known for a long time; however, recently the attention of scientists and apiculturalists has turned towards the relationship between these viruses and the parasitic mite varroa jacobsoni. although clinical symptoms indicated the presence of some of the viruses of bees in hungary, none have previously been isolated or identified. during july unusual adult bee and brood mortality was observed in some colonies of an apiary in budapest known to be infested with var ... | 1999 | 10497825 |
| identification and transcriptional analysis of the homologues of the herpes simplex virus type 1 ul30 to ul40 genes in the genome of nononcogenic marek's disease virus serotype 2. | studies on marek's disease virus serotype 2 (mdv2) are important for understanding the natural nononcogenic phenotype of mdv. this study reports a 27,535 bp nucleotide sequence of part of the mdv2 genome located in the central unique long (u(l)) region. the analysis revealed 11 complete orfs with high amino acid sequence identities to the products of other alphaherpesviruses. the mdv2 orfs were arranged collinearly with the prototype sequence of herpes simplex virus type 1, ranging from the ul30 ... | 1999 | 10501496 |
| a quantitative duplex pcr technique for measuring amounts of cell-associated marek's disease virus: differences in two populations of lymphoma cells. | a duplex polymerase chain reaction (pcr) was developed to measure marek's disease virus (mdv) load in two subpopulations of marek's disease (md) lymphoma cells from chickens. pcr primers were designed using the sequence of the mdv-icp4 gene and the chicken ifngamma gene. each set of primers was present in the same reaction tube so that the 327 bp icp4 product and the 420 bp ifngamma product were co-amplified. two different fluorescent dyes were used to 5'-end label one pcr primer of each pair to ... | 1999 | 10507410 |
| atherosclerosis induced by infection with marek's disease herpesvirus in chickens. | this research was suggested after crystals that we observed in herpesvirus-infected cell cultures were identified as cholesterol. other reports and the development of defined reagents led us to select the use of marek's disease herpesvirus (mdv) infection of chickens to demonstrate a potential role of herpesviruses in the pathogenesis of atherosclerosis. available for our use were a clone-purified strain of mdv of known virulence, genetically selected, specific pathogen-free chickens, and approp ... | 1999 | 10539849 |
| anti-viral and anti-tumor effects induced by an attenuated marek's disease virus in cd4- or cd8-deficient chickens. | by vaccination with an attenuated marek's disease virus (mdv), strain cvi988, chickens are protected from the development of t cell lymphoma caused by an oncogenic mdv. to clarify the role of t lymphocyte subsets in the protection mechanisms of this vaccine, vaccinated chickens were depleted of t cell subsets by neonatal thymectomy and injections of monoclonal antibodies specific to chicken cd4 and cd8 molecules, and then challenged with an oncogenic mdv, strain md5. the mdv titers rescued from ... | 1999 | 10542027 |
| sequence and initial characterization of the u(l)10 (glycoprotein m) and u(l)11 homologous genes of serotype 1 marek's disease virus. | the nucleotide sequence of the u(l)10 (glycoprotein m) and the u(l)11 homologs of marek's disease virus 1 strain ga was determined. the u(l)10 open reading frame encodes a type iii membrane protein of 424 amino acids that contains eight hydrophobic domains and two consensus n-linked glycosylation sites. the u(l)11 homologous gene encodes an 84 amino acid polypeptide, and contains a highly conserved myristylation site at its aminoterminus. by analysis of infected-cell rna with strand-specific rna ... | 1999 | 10542032 |
| the bi-directional transcriptional promoters for the latency-relating transcripts of the pp38/pp24 mrnas and the 1.8 kb-mrna in the long inverted repeats of marek's disease virus serotype 1 dna are regulated by common promoter-specific enhancers. | in cell lines established from marek's disease tumors, several viral transcripts are expressed and among them the products of pp38/pp24 mrna and 1.8 kb-mrna have been suggested to be involved in viral oncogenicity. the long inverted repeats of marek's disease virus serotype 1 (mdv1) genome contain closely located transcriptional promoters for phosphorylated protein pp38/pp24 and 1.8 kb-mrna. these promoters initiate transcription in opposite directions and are separated only by a short enhancer ... | 1999 | 10550664 |
| identification of the marek's disease virus serotype 2 genes homologous to the glycoprotein b (ul27), icp18.5 (ul28) and major dna-binding protein (ul29) genes of herpes simplex virus type 1. | we determined the nucleotide sequence of non-pathogenic marek's disease virus serotype 2 (mdv2) strain hprs24 glycoprotein b (gb) (ul27), icp18.5 (ul28) and major dna-binding protein (mdbp) (ul29) genes homologous to herpes simplex virus type 1 (hsv-1). the sequence data revealed that important motives in the proteins are conserved in mdv2 icp18.5 and mdbp, however the sequence of viral dna replication origin which exists in the regions between the ul29 and ul30 genes of other alphaherpesviruses ... | 1999 | 10563297 |
| an acute form of transient paralysis induced by highly virulent strains of marek's disease virus. | a novel syndrome was observed after inoculation of 3-wk-old chickens with highly virulent marek's disease virus (mdv) strains. this syndrome was characterized by the acute onset of neurologic signs including flaccid paralysis of neck and limbs 9-10 days postinoculation, typically resulting in death 1-3 days after the onset of clinical signs. most affected birds died, and spontaneous recovery was rare. few if any gross tissue changes were found. histologic brain lesions included acute vasculitis ... | 1999 | 10611987 |
| four distinct neurologic syndromes in marek's disease: effect of viral strain and pathotype. | a chronological study of central nervous system disorders induced by marek's disease virus (mdv) has been conducted. neurologic clinical signs were recorded daily for individual chickens of two genetic lines after inoculation of 13 serotype 1 mdv strains representing all three pathotypes. in addition to classical transient paralysis (tp) previously described by many workers, and acute tp, described in the companion paper, we have identified for the first time two other neurologic syndromes, pers ... | 1999 | 10611988 |
| renal cryptosporidiosis (cryptosporidium baileyi) in specific-pathogen-free chickens experimentally coinfected with marek's disease virus. | renal cryptosporidiosis was experimentally induced during a study to investigate the pathogenicity of cryptosporidium baileyi in specific-pathogen-free (spf) chickens coinfected with marek's disease virus (mdv). cryptosporidium baileyi was administered orally at 4 days of age to chickens previously infected at hatching (day 0) with the hprs 16 strain of oncogenic mdv. three control groups received mdv at hatching, c. baileyi on day 4, or placebo consisting of distilled water. renal cryptosporidi ... | 1999 | 10611989 |
| a comparison of the onset of protection induced by newcastle disease virus strain b1 and a fowl poxvirus recombinant newcastle disease vaccine to a viscerotropic velogenic newcastle disease virus challenge. | four-week-old specific-pathogen-free white rock chickens were immunized with either a commercial recombinant fowl poxvirus-vectored newcastle disease vaccine (fpn) expressing the hemagglutinin-neuraminidase and fusion protein genes of newcastle disease virus (ndv) strain b1 or live ndv b1. vaccinates and controls were challenged by eyedrop and intranasal (e/i) route with a viscerotropic velogenic ndv at 14 days postvaccination to determine the time of clearance of challenge virus. in a subsequen ... | 1999 | 10611990 |
| the dynamic herpesvirus dna genome: the case of mdv-1 and hsv-1. | herpesviruses evolved from an ancestral viral genome that contained five blocks of genes which provide the members of this family of viruses with structural and enzymatic properties. these genes allow the herpesviruses to infect a host by entering into the nuclei of the cells, the site of replication and transcription of the viral dna. the viral mrnas are released into the cell cytoplasm where synthesis of enzymatic and structural proteins occurs. the latter proteins are responsible for the form ... | 1999 | 10696425 |
| molecular characteristics of very virulent european mdv isolates. | marek's disease virus (mdv) strains with increasing virulence have been reported from many parts of the world. many of these recent mdv isolates produce an acute early cytolytic disease with high mortality and severe atrophy of the lymphoid organs, thymus and the bursa of fabricius. although the degree of the atrophic changes and the virulence of the virus are correlated, the molecular basis of the increased virulence is not known. we examined the characteristics of the disease induced by 3 such ... | 1999 | 10696426 |
| meq and v-il8: cellular genes in disguise? | one of the hallmarks of oncogenic viruses is their ability to subvert the growth regulation and evade immune response of the host. there are a number of tricks devised by various virus families. oncogenic herpesviruses often accomplish this by encoding homologs of cellular genes involved in these functions. these viral homologs sometimes are hyperactive forms of their cellular counterparts, which function to overtake the cellular pathways, other times serve as decoys to mask the cellular functio ... | 1999 | 10696427 |
| comparison of two serotype 1 mdv isolates. | we compared the rb1b and t. king (tk) serotype 1 isolates of marek's disease virus (mdv) in vivo. body and organ weights, mortality, and lesions indicated that the tk inoculum established early infection more efficiently than rb1b and did greater damage to the bursa of fabricius and thymus. subsequent studies showed that the tk inoculum that we used contained chicken infectious anemia virus (ciav). therefore, pathogenicity profiles shown here should be interpreted with the presence of ciav conta ... | 1999 | 10696428 |
| establishment of a lymphoblastoid cell line using a mutant mdv containing a green fluorescent protein expression cassette. | we have previously described the construction and characterization of mutant marek's disease viruses (mdvs) having mutations within the unique-short (us) region of the genome that have retained oncogenicity (anderson et al., 1998; parcells et al., 1995). we have also reported the characterization of lymphoblastoid cell lines (lbcls) derived using these mutant viruses (parcells et al., 1998). these mutant mdvs were constructed using a lacz expression cassette. expression of lacz was found to be c ... | 1999 | 10696429 |
| a monoclonal antibody to icp4 of mdv recognizing icp4 of serotype 1 and 3 mdv strains. | monoclonal antibodies (mabs) were prepared against icp4 of marek's disease virus (mdv). mice were inoculated with icp4 obtained from high-five insect cells infected with a recombinant baculovirus expressing icp4. mabs were selected by enzyme-linked immunosorbent assay (elisa) using mdv-infected and control chick kidney cells as antigens. one of the mabs, 5h8, recognized an epitope toward the carboxyl terminus of icp4 based on staining of reticuloendotheliosis virus-transformed cells transfected ... | 1999 | 10696430 |
| effect of native chicken interferon on mdv replication. | marek's disease virus (mdv) is an oncogenic alphaherpesvirus. its specific phosphorylated protein, pp38 has been implicated in mdv oncogenesis. in order to check whether the known anti-viral or anti-proliferative actions of interferon (ifn) are of importance in marek's disease (md), chicken embryo fibroblasts (cefs) were infected with attenuated serotype-1 mdv strain cvi988, or with herpesvirus of turkeys (hvt). different concentrations of native chicken ifn were added to the cell cultures, prio ... | 1999 | 10696431 |
| expression of bcl-2 and bcl-x genes in lymphocytes and tumor cell lines derived from mdv-infected chickens. | to characterize the molecular events involved in both apoptosis and transformation process induced by marek's disease virus (mdv), the expressions of the bcl-2 and bcl-x genes, ones of the dominant apoptosis-regulating genes, in marek's disease (md) tumor cell lines and cells prepared from mdv-infected chickens were analyzed. the expression of bcl-2 was down-regulated in both cd4+ and cd8+ t cells prepared from mdv-infected chickens at 3 weeks p.i. no bcl-2 transcript was detected in md tumor-de ... | 1999 | 10696432 |
| inhibition of apoptosis by marek's disease viruses. | strains of marek's disease virus (mdv), a herpesvirus, have been shown to augment the development of lymphoid leukosis induced by retroviruses, the avian leukosis virus (alv) or the reticuloendotheliosis virus. in this study we explored the possibility that the ability to augment lymphoid leukosis may be correlated with the ability of different strains of mdv to block apoptosis. subclones of the alv-transformed b cell line, dt40, which was free of mdv dna were infected with either r2/23 strain o ... | 1999 | 10696433 |
| multiple infection of chickens and turkeys with avian oncogenic viruses: prevalence and molecular analysis. | the avian herpesvirus, marek's disease virus (mdv) and several retroviruses, reticuloendotheliosis virus (rev), avian leukosis virus (alv) (chickens) and lymphoproliferative disease virus (turkeys) are oncogenic and immunosuppressive agents. these viruses were detected either alone, or in various combinations in blood and tumor dnas of commercial birds using pcr. we present a 5-year retrospective study that included 207 chicken and 52 turkey flocks. of these, 32 chicken and 18 turkey flocks were ... | 1999 | 10696434 |
| evidence for marek's disease in turkeys in germany: detection of mdv-1 using the polymerase chain reaction. | since 1994 tumorous lesions have been monitored in turkeys on three farms in germany. on one of these farms, chickens also had tumorous lesions. affected turkeys were retarded in growth, apathic, pale and almost unable to move. the older the animals got, the more indistinct the clinical signs became. mortality started at an age of 5 weeks and reached between 20% and 60% by the end of the fattening period of about 20 weeks. the aetiological differential diagnosis includes reticuloendotheliosis (r ... | 1999 | 10696435 |
| identification and characterization of glycoprotein h of mdv-1 ga strain. | a 2439 bp open reading frame (orf) was identified from the dna sequence of bamhi-f and -k2 fragments of marek's disease virus of serotype 1 (mdv-1) ga strain, which predicts an 813 amino acid polypeptide. this peptide is homologous to hsv-1 gh, and has typical glycoprotein features. there are nine potential n-linked glycosylation sites within the extracellular domain. a fragment of the gh orf was cloned into pgex vector in frame with glutathione s-transferase (gst) to produce a gst-gh fusion pro ... | 1999 | 10696437 |
| mdv glycoprotein d is expressed in the feather follicle epithelium of infected chickens. | glycoprotein d (gd) and its homologues are essential for many alphaherpesvirus life cycles. a gene encoding a homologue of gd was recently found in the marek's disease virus (mdv) genome. interestingly, gd-negative mdv mutants apparently replicate unimpaired in both cell culture and chickens. in this study, we show the expression of the gd homologue of mdv in feather follicle epithelium in infected birds. the gd homologue was detected in a few feather follicles even when most of the follicles we ... | 1999 | 10696438 |
| glycoprotein gd of mdv lacks functions typical for alpha-herpesvirus gd homologues. | glycoprotein d (gd) belongs to family of conserved structural proteins of alpha-herpesviruses. during productive infection of cells by herpes simplex virus 1 (hsv-1) gd has several important functions, is involved in virus penetration to and release from infected cells and is one of main targets of neutralizing antibodies. similar functions are shared also by other alpha-herpesvirus gd homologues. surprisingly, in previous studies it was found that mdv gd expression could not be detected during ... | 1999 | 10696439 |
| construction and characterization of a h19 epitope point mutant of mdv cvi988/rispens strain. | a recombinant virus, cvi/rpp38, was developed from the marek's disease virus (mdv) cvi988/rispens vaccine strain. this recombinant was obtained by transfection of cvi988/rispens-infected chick embryo fibroblasts (cefs) with plasmid pha25 dna containing pp38 gene from ga strain of mdv. monoclonal antibody (mab) h19 which reacts with pp38 from ga but not with that from cvi988 was used to screen for recombinant viruses in transfected cell culture plates by immunofluorescent assay (ifa). a positive ... | 1999 | 10696440 |
| identification and structural analysis of a mdv gene encoding a protein kinase. | dna sequence analysis of the bamhi-c fragment of marek's disease virus (mdv) reveals the presence of a 513 amino acid open reading frame (orf). this orf codes for a protein with an estimated m(r) of 58,901. comparison of the amino acid sequence with those available in the swiss-prot database indicates extensive homology with a protein kinase (pk) of herpes simplex virus (hsv) and varicella-zoster virus (vzv). in northern blot hybridization, a transcript of 2.0 kb was detected in mdv (ga strain) ... | 1999 | 10696441 |
| non-essential loci in the bamhi-i and -f fragments of the hvt fc126 genome. | the sequence of bamhi-i fragment of the herpesvirus of turkeys (hvt) fc126 strain dna was analyzed for the presence of potential open reading frames (orfs). four complete (orfs 2 to 5) and 2 partial orfs (orfs 1 and 6) were detected. orfs 2 and 3 were homologous to the hsv-1 ul55 and the ehv-1 gene 3, respectively. the orf 6 was already partially sequenced by smith et al. (virology 207, 205-216, 1995), and was homologous to a marek's disease virus (mdv) orf located in a similar position (orf 21; ... | 1999 | 10696442 |
| development of a cell line system susceptible to infection with vaccine strains of mdv. | despite reliance on the need to continually prepare fresh cultures of chick embryo fibroblasts (cefs) to make marek's disease (md) vaccines, md vaccines are the most widely used vaccines in the poultry industry. preparation of cef's accounts for approximately 40% of the costs associated with producing md vaccines. a significant reduction in md vaccine production costs could be realized if a continuous cell lines were available for md vaccine production. recently, we reported development and char ... | 1999 | 10696443 |
| efficacy of a combination vaccine containing mdv cvi 988 strain and hvt against challenge with very virulent mdv. | with the emergence of very virulent marek's disease virus (mdv) strains, vaccines based on herpesvirus of turkeys (hvt) appear to be not powerful enough to confer full protection, whereas in chicken flocks vaccinated with mdv cvi 988 strain protective immunity sometimes is generated not early enough for full protection. for this reason combination vaccines containing hvt as well as cvi 988 have been developed. in this paper the beneficial effect of combining both types of virus strains in one va ... | 1999 | 10696445 |
| a recombinant fowlpox virus vaccine expressing glycoprotein b gene from cvi988/rispens strain of mdv: protection studies in different chickens. | recombinant fowlpox virus (rfpv) was constructed to express glycoprotein b (gb) gene from cvi988/rispens strain of marek's disease virus (mdv). the rfpv-gb/r alone and in combination with herpesvirus of turkey (hvt) preparations were evaluated for their protective efficacy against challenge with very virulent mdv strains md5 and rb1b in different chickens. the rfpv-gb/r alone induced protection comparable to that by hvt vaccines in both ab- spf chickens and ab+ production chickens. significant p ... | 1999 | 10696446 |
| development and composition of lymphoid lesions in the spleens of marek's disease virus-infected chickens: association with virus spread and the pathogenesis of marek's disease. | changes in lymphocyte distribution in spleens of marek's disease virus (mdv) infected white leghorn chickens of line 72 (md susceptible) and line 61 (md resistant) were studied by immunocytochemistry. lymphocytes expressing the mdv antigen pp38 (predominantly b cells) were detected from 4 to 6 days post-inoculation (d.p.i.) but not at or after 8 d.p.i., and were more numerous in line 72. in line 61, infection resulted in depletion of b lymphocytes and an increase in t lymphocytes from 3 to 6 d.p ... | 1999 | 26915385 |
| multi-centric histiocytosis: experimental induction in broiler and specific pathogen-free leghorn chickens. | seventy-five 3-day-old broiler chicks and twenty specific pathogen-free leghorn chicks were injected with 0.5 ml of a homogenate, prepared from organs from broilers diagnosed with naturally-occurring multicentric histiocytosis (mh). equal numbers of uninjected broiler and leghorn chicks (controls) were maintained in adjacent pens. ten weeks later, nine broilers had well-developed gross and microscopic mh lesions. the distribution and histological appearance of lesions in these experimental chick ... | 1999 | 26915383 |
| [detection and typing of the genome of marek's disease virus using polymerase chain reaction]. | 1998 | 9914981 |