Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| pathogenesis of infection with attenuated marek's disease virus strains. | recently, attenuated marek's disease virus (mdv) became of renewed interest as a component in bi- or polyvalent vaccines. the effect of attenuation on the pathogenesis of infection was investigated. cloned preparations of the jm-16, bc-1a and rb-1b strains of mdv were attenuated by serial passage in chick kidney cells or chicken embryo fibroblasts. subclones were obtained from the jm-16 strain at passage (p) 26 (jm-16d) and 50 (jm-16a, b and c). the passage level at which each virus became atten ... | 1985 | 18766904 |
| protection by attenuated and polyvalent vaccines against highly virulent strains of marek's disease virus. | tests confirmed that turkey herpesvirus (hvt) vaccine protected chickens poorly against challenge with the highly virulent md5 strain of marek's disease (md) virus, especially in chickens with homologous hvt antibodies. the naturally avirulent sb-1 vaccine virus was likewise poorly protective against challenge with the md5 strain. homologous antibodies reduced the protective efficacy of both vaccines, but sb-1 was not affected by hvt antibodies. in order to provide better protection against stra ... | 1982 | 18770172 |
| ultrastructure of the central nervous system in marek's disease and the effect of route of infection on lesion incidence in the central nervous system. | the ultrastructure of the lesions of the central nervous system (cns) of chickens was examined at intervals after intra-abdominal inoculation of marek's disease virus (mdv). no transient paralysis occurred. peri-vascular accumulations of lymphocytes and macrophages (cuffing) were accompanied by invasion of the cns by these blood-borne leukocytes in the most severe lesions. only minor damage to axons, myelin or glial cells was detected and no structural evidence for viral replication was observed ... | 1982 | 18770186 |
| characterisation of two highly oncogenic strains of marek's disease virus. | the rb-1b and ala-8 strains of marek's disease (md) virus, which were isolated from chickens with md and which had been vaccinated with the herpesvirus of turkeys (hvt), were evaluated for their oncogenic potential in genetically susceptible (p-line) and resistant (n-line, pdrc) chickens. rb-1b and ala-8 were both highly oncogenic, causing a high incidence of md in both susceptible and resistant birds. vaccination of p-line birds with sb-1 or hvt did not protect satisfactorily against rb-1b. how ... | 1982 | 18770225 |
| failure of attenuated marek's disease virus and herpesvirus of turkeys antigens to protect against the jmv marek's disease-derived transplant able tumour. | chickens immunised with chick embryo fibroblasts infected with attenuated marek's disease virus or with the herpesvirus of turkeys and inactivated with glutaraldehyde were not protected against the lethal effects of inoculation with the marek's disease-derived tumour transplant, jmv, although such immunisation protected against experimentally induced marek's disease. it is concluded that there may be virus-coded antigenic determinants that are peculiar to oncogenic marek's disease viruses and la ... | 1980 | 18770257 |
| a new herpesvirus isolated from black storks (ciconia nigra). | an infectious agent was isolated from livers, spleens and bone marrow of two black storks (ciconia nigra l.) originating from the same source. pathological lesions consisted of small whitish focal areas in livers, spleens and bone marrow. the isolated agent was sensitive to chloroform and its multiplication was inhibited by 5-iodine-2-deoxy-uridine. it passed filters with a pore diameter of 220 nm and greater but not 100 nm filters. electron microscopic examination revealed numerous nucleocapsid ... | 1980 | 18770269 |
| a quantitative sequential study of viraemia and neutralising antibody to hvt and mdv in a commercial flock vaccinated with hvt. | levels of viraemia due to the herpesvirus of turkeys (hvt) and neutralising antibodies to hvt and marek's disease virus (mdv) were followed in a flock of commercial broiler breeders held in commercial premises and vaccinated at 1-day-old with hvt. the flock was sampled at 3, 5 and 8 weeks of age and then at 4-weekly intervals until 32 weeks of age. the mean viraemia titre was highest at 3 and 5 weeks and then fell to a low level by 16 weeks where it remained until 32 weeks of age. at all samplin ... | 1980 | 18770292 |
| lack of beneficial effect of levamisole on marek's disease. | levamisole hydrochloride administered by subcutaneous inoculation at 2.5 mg/kg or 25 mg/kg bodyweight under three dosage regimens to chicks infected by marek's disease virus had no beneficial influence on the course of the disease. | 1980 | 18770293 |
| the effect of bursectomy on vaccination against marek's disease with the herpesvirus of turkeys. | protection against marek's disease following vaccination with the herpesvirus of turkeys was significantly impaired but not abolished by ablation of the bursa-dependent lymphoid system by surgery and x-irradiation. it was concluded that the humoral immune system is relatively more important in vaccinal immunity induced by the herpesvirus of turkeys compared with that induced by attenuated marek's disease virus. | 1980 | 18770297 |
| the effect of virus dose on the development of marek's disease in two strains of chickens. | the effect of inoculating different doses of marek's disease virus on the consequent lymphocyte-associated viraemia titres, survival time and mortality was studied in two strains of chickens, one highly susceptible (a strain of rhode island red) and one moderately resistant (a strain of light sussex) to marek's disease. in both strains an increase in the infecting dose of virus increased the ensuing viraemia, and there was an inverse relationship between virus dose and survival time. there was a ... | 1980 | 18770298 |
| marek's disease virus-induced antigens in relation to immunity. | protection experiments using isolated marek's disease (md) antigens were performed in antibody-free rhode island red chickens. in addition to virus a antigen (mdv-a) and herpes virus of turkeys (hvt)-induced intracellular (hvt-via) antigens, tumour-specific antigens from the lympho-blastoid msb-1 cells were prepared and isolated plasma membranes were used as vaccines. neither the tested mdv-a and hvt-via nor tumour-specific marek's disease antigens induced statistically significant protection in ... | 1977 | 18770329 |
| disinfection of marek's disease virus in poultry dust. | dust samples from farms contaminated with marek's disease virus (mdv) were exposed to various disinfectants under experimental and field conditions. after the disinfection treatment, examination was made for the presence and oncogenicity of surviving mdv by the inoculation of tissue cultures and susceptible chickens. a combination of formaldehyde vapour and a preparation based on iodine bound to organic carriers appeared to be the most effective for disinfection. | 1977 | 18770332 |
| cross-protection between jmv marek's disease-derived tumour transplant, marek's disease and turkey herpesviruses. | cross-protection tests were conducted using attenuated jmv (jmv-a) marek's disease-derived lymphoblasts, glutaraldehyde-treated jmv tumour cells, attenuated marek's disease virus (mdv, strain hprs-16/att) and turkey herpesvirus (hvt, strain fc126) as vaccines, and virulent jmv and mdv (hprs-16) for challenge. the jmv and jmv-a preparations were free of mdv, leukosis and reticuloendotheliosis viruses. vaccination of chickens with attenuated mdv or with hvt provided good protection against both jm ... | 1977 | 18770345 |
| further characterisation of the cvi 988 strain of marek's disease virus. | the cvi 988 strain of marek's disease virus (mdv) has been studied for markers in vitro and in vivo. it was shown by indirect immunofluorescence assays that this strain belonged to the hprs-16 serotype of md viruses. the virus was positive for precipitating 'a' antigen. medium plaques were produced in cell cultures. therefore the cvi 988 strain could not be distinguished in vitro from other virus strains of the same serotype. the cvi 988 strain proved to be pathogenic for genetically susceptible ... | 1977 | 18770348 |
| quantitative pathogenicity of marek's disease virus and vaccine virus strains in chickens: macroscopical aspects. | two virulent strains (jm and k) and one vaccine strain (cvi 988) of marek's disease virus (mdv), together with two vaccine strains of the herpesvirus of turkeys (hvt) (fc 126 and pb-thv 1), all in the cell-associated state, were administered intramuscularly at 3.7 log tcid50 per dose to day-old spf white leghorn chickens. a control group of chicks received uninfected cells. the pathological parameters studied were onset and duration of clinical symptoms, mortality, bird weight and macroscopical ... | 1978 | 18770360 |
| absence of marek's disease virus antigen in the feather follicle epithelium of vaccinated chicks demonstrated by immunofluorescence. | in chickens vaccinated with mdv strain cvi 988, hvt strain fc 126 or pb-thv 1, no mdv-specific antigens could be demonstrated in the feather follicle epithelium by immunofluorescence (if). in chickens given virulent mdv strains, the epithelium of the feather follicle was positive in if. in an experiment where chickens were vaccinated with strain cvi 988, positive if was observed in the lung, bursa and pancreas, but not in the feather follicle epithelium, kidney, cloaca, or caecal tonsils. absenc ... | 1978 | 18770361 |
| lymphoproliferative disease of turkeys. ii. experimental transmission and aetiology. | the clinical and pathological features of a previously reported lympho-proliferative disease of turkeys were reproduced by inoculation of 4-week-old poults, and spread to in contact turkeys was demonstrated. from studies on the development of the lesions in inoculated turkeys, it was possible to assay the causative agent based on microscopic examination of early lesions. poults were more susceptible to inoculation when 4 weeks old than to inoculation at 1 day old, and different strains of turkey ... | 1978 | 18770366 |
| protection against the jmv marek's disease-derived transplantable tumour by marek's disease virus-specific antigens. | chickens immunised with inactivated chicken kidney cells infected with marek's disease (md) virus were protected against the lethal effects of inoculation with the md-derived tumour transplant jmv, which appears not to express viral antigens. it is concluded that the distinction between md virus-specific and tumour-specific antigens is not as complete as has been thought. | 1978 | 18770382 |
| vaccination of bursectomised chickens with inactivated marek's disease virus-specific antigens. | bursectomised chickens were protected against marek's disease (md) by vaccination with inactivated md virus-specific antigens. the immunity was associated with lowered lymphocyte-associated md viraemia following challenge. evidence is presented that the immunity was not dependent on a humoral immune response but possibly on the presence of lymphocytes sensitised to virus-specific antigens. | 1978 | 18770396 |
| anti-viral immunity against marek's disease virus infected chicken kidney cells. | the mechanism of immunity conferred by herpesvirus of turkeys (hvt) was investigated using marek's disease virus (mdv)-infected chicken kidney cell (ckc) cultures as target cells. peripheral blood lymphocytes (pbl) from normal or hvt-vaccinated chickens killed mdv-infected target cells in the presence of anti-mdv or anti-hvt serum, whereas normal lymphocytes and hvt-sensitised lymphocytes themselves had no specific cytotoxic effect. cell-mediated cytotoxicity of pbl from hvt-vaccinated chicken w ... | 1979 | 18770425 |
| serological characterisation of marek's disease tumour-associated surface antigens on marek's disease lymphoma cells and on cell lines derived from marek's disease lymphomas. | antisera produced in rabbits against marek's disease lymphoma cells and against four lymphoma-derived cell lines (hprs lines 1 and 2, msb-1 and rpl-1) appeared, after extensive absorption with normal chicken cells, to react specifically by indirect immunofluorescent staining with antigens unique to marek's disease tumour cells. the antigens present on the four cell lines were shown by antiserum titration and absorption tests to be related but not identical. the possibility is discussed that cell ... | 1979 | 18770440 |
| marek's disease vaccines: a solution for today but a worry for tomorrow? | marek's disease (md) is a lymphoproliferative disease of chickens that, in the absence of control measures, is capable of causing devastating losses in commercial poultry flocks. md has been successfully controlled by vaccination since 1968. however, vaccine efficacy has decreased concomitantly with the increase in virulence of marek's disease virus (mdv). the constant evolution of mdv has forced the development of new vaccines or vaccine strategies that control the more virulent emergent strain ... | 2008 | 18773529 |
| a study of vaccination against marek's disease with an attenuated marek's disease virus. | approximately 2,000 day-old white leghorn chickens were distributed into 10 pens and half the pens vaccinated with the attenuated strain of hprs-16. at 72 weeks of age, mortality from non-specific death and marek's disease was 17.6% and 15.6% respectively, in vaccinated chickens compared with 14.2% and 51.7% in unvaccinated chickens. body weights of vaccinated chickens were 5.6% higher at 8 weeks of age than unvaccinated chickens. vaccinated chickens consumed 2.3% more feed and the hen housed eg ... | 1974 | 18777267 |
| comparative features of low-virulence and high-virulence marek's disease virus infections. | virus clones from 2 marek's disease virus (mdv) isolates from flocks with low natural incidences of marek's disease (md) were, at most, only mildly pathogenic compared to clones from the highly virulent jm isolate. clones from a single donor bird appeared to vary in pathogenicity. the infectivity and pathogenicity of cu-2 (low virulence) and jm-10 (high virulence) were compared with age, genetic constitution and virus dosage as variables. in jm-10 infection, s-strain birds had only neural and go ... | 1974 | 18777279 |
| efficacy of marek's disease vaccines: protection and viraemia studies with turkey herpes virus vaccines. | two freeze dried turkey herpes virus vaccines a and c, of similar virus content were administered in graded doses to groups of day old chicks which were genetically susceptible to marek's disease. immediately after vaccination the chicks were challenged by contact with 4-weeks-old birds that had been infected at one day of age with virulent marek's disease virus strain hprs 16. assessment of protection against marek's disease was based on the absence of gross lesions after a 15 week observation ... | 1975 | 18777298 |
| differentiation between strains of marek's disease virus and turkey herpesvirus by immunofluorescence assays. | two serological types of marek's disease virus and a herpesvirus of turkeys have been differentiated by indirect immunofluorescence tests as (1) pathogenic strains of marek's disease virus (mdv) and their attenuated variants: hprs-16, hprs-16/att, hprs-b14, jm, jm/att, ga, vc and 'oldenburg', a recent field isolate; (2) apathogenic strains hprs-24 and hprs-27 of mdv; (3) herpesvirus of turkeys strain fc126 and its hvt(a-) variant. virus strains could not be distinguished on the basis of qualitat ... | 1975 | 18777301 |
| precipitating antigens associated with marek's disease viruses and a herpesvirus of turkeys. | precipitating antigens associated with a number of marek's disease virus strains and with a turkey herpesvirus have been analyzed. the 'a' antigen has been defined as the major soluble antigen in feather follicles of infected chickens, which is identical with the major antigen usually present in supernatants of chicken kidney cell cultures infected with strains of marek's disease virus. 'bc' antigens are 2 or more antigens which are usually not noted in skin extracts but present in cultured cell ... | 1975 | 18777302 |
| the epizootiology of marek's disease. 3. the interrelationship of virus pathogenicity, antibody and the incidence of marek's disease. | approximately 1000 day-old white leghorn chickens were distributed into 5 pens in a brooder house and exposed to natural infection with marek's disease virus (mdv). observations were made on the inter-relationship between strains of mdv infecting the chickens, precipitating antibody, incidence of marek's disease (md), body weight, egg production, feed consumption and stress through movement. a wide variation in mortality from md occurred between similar pens in the same brooding house. it was fo ... | 1976 | 18777336 |
| histo-morphometric analysis applied to spleens of marek's disease virus inoculated chickens. | as part of a larger experiment to compare the pathogenic effects of different strains of marek's disease virus, a counting procedure for tissue components in histological sections is presented which may quantify the relative volumes occupied by the components. the method is demonstrated on spleens taken from 8-weeks-old chickens, treated at one-day-old with a cell-associated pathogenic strain of marek's disease virus (mdv), a cell-associated vaccine strain, or a mdv-free cell suspension. | 1976 | 18777345 |
| [a method for partial purification of marek's disease herpesvirus a-antigen from feather follicles of infected chicken]. | a method for partial purification of marek's disease herpesvirus a antigen from feather follicles of infected chickens is described. the a antigen partially purified by ph 4 treatment and affinity chromatography when analyzed in polyacrylamide gel electrophoresis was found to be a mixture of 7 coomassie blue stained fractions. | 1976 | 18777347 |
| the epizootiology of marek's disease: i. incidence of antibody, viraemia and marek's disease in six flocks. | six flocks consisting of the female grandparent line of a well known broiler strain were studied in an effort to determine the important aetiological factors in marek's disease. each flock was hatched in the same hatchery but at intervals of six weeks. chicks of each flock were reared to between 8 and 9 weeks of age on a rearing site after which they were moved to a production site. mortality was recorded to house and pen in all flocks. in addition six pens of about 300 chickens on each of the p ... | 1972 | 18777367 |
| an age-related resistance of chickens to marek's disease: some preliminary observations. | chickens of 2 strains, 20 to 22 weeks of age and free of prior infection, were substantially more resistant than l-day-old chicks to mortality and tumor induction caused by exposure to marek's disease virus. these older chickens were refractory to inoculation with up to 10(4) chick tumor-inducing doses of marek's disease virus and, following contact infection, lesion frequencies were 8 to 30% of corresponding responses in chick controls. resistance in contact exposed chickens was observed as ear ... | 1973 | 18777381 |
| lack of a threshold of genetic resistance to marek's disease and the incidence of humoral antibody. | on challenge exposure of genetically susceptible (line 7) and genetically resistant (line 6) chickens to graded doses of marek's disease virus, line 5 chickens were at least 10(6)-fold more resistant to clinical marek's disease than line 7 chickens. hence, if there was a "threshold" of resistance of line 6 chickens to the disease, it was not overcome by 10(6) times the dose of marek's disease virus required to induce neoplastic response in line 7. approximately similar doses of virus were requir ... | 1973 | 18777387 |
| using integrative genomics to elucidate genetic resistance to marek's disease in chickens. | while rearing birds in confinement and at high density are very successful practices for producing poultry meat and eggs, these conditions may promote the spread of infectious diseases. consequently, the poultry industry places greatemphasis on disease control measures, primarily at the animal husbandry level. the field of genomics offers great promise to complement these current control measures by providing information on the molecular basis for disease, disease resistance, and vaccinal immuni ... | 2008 | 18817328 |
| sequence conservation and differential expression of marek's disease virus micrornas. | marek's disease virus (mdv), a herpesvirus that causes a lymphoproliferative disorder in chickens, encodes a number of micrornas derived primarily from two locations in the mdv genome. one cluster of microrna genes flanks the meq oncogene, and a second cluster is found within the latency-associated transcript (lat) region. the sequences of mdv micrornas from a collection of field and reference strains with various levels of virulence were compared and found to be highly conserved. however, micro ... | 2008 | 18842708 |
| a functional microrna-155 ortholog encoded by the oncogenic marek's disease virus. | kaposi's sarcoma-associated herpesvirus-encoded microrna (mirna) mir-k12-11 was recently shown to be a functional ortholog of mir-155, a mirna that plays a major role in lymphoid malignancies and the modulation of immune responses. here we show that mir-m4, encoded by the highly oncogenic marek's disease virus of chickens, shares common targets with mir-155 and thus is also a functional ortholog of mir-155, the first one identified in an alphaherpesvirus. the observation that two distinct oncoge ... | 2009 | 18945769 |
| homodimerization of marek's disease virus-encoded meq protein is not sufficient for transformation of lymphocytes in chickens. | marek's disease virus (mdv), the etiologic agent of marek's disease, is a potent oncogenic herpesvirus. mdv is highly contagious and elicits a rapid onset of malignant t-cell lymphomas in chickens within several weeks after infection. mdv genome codes an oncoprotein, meq, which shares resemblance with the jun/fos family of bzip transcription factors. similar to jun, the leucine zipper region of meq allows the formation of homo- and heterodimers. meq homo- and heterodimers have different dna bind ... | 2009 | 18971275 |
| targeting marek's disease virus by rna interference delivered from a herpesvirus vaccine. | live attenuated herpesvirus vaccines such as herpesvirus of turkey (hvt) have been used since 1970 for the control of marek's disease (md), a highly infectious lymphoproliferative disease of poultry. despite the success of these vaccines in reducing losses from the disease, marek's disease virus (mdv) strains have shown a continuing increase in virulence, presumably due to the inability of the current vaccines in preventing mdv replication. the highly specific and effective nature of rna interfe ... | 2009 | 18977264 |
| mdv-1 vp22 conjugated vp2 enhancing immune response against infectious bursal disease virus by dna vaccination in mice. | vp22 of marek's disease virus serotype 1 (mdv-1) could function in protein transduction. in this study, an infectious bursal disease virus vp2 gene was fused to the carboxyl termini of vp22. it showed that the fusion protein did not spread into the bystander cells from the cells transfected with pvp22-vp2, as the vp22 alone could. the vp22 proteins were found to be translocated into all the nuclei in the neighboring cos-1 cells, as analyzed by a fluorescence assay. although mice were immunized w ... | 2008 | 18989640 |
| construction of an infectious marek's disease virus bacterial artificial chromosome and characterization of protection induced in chickens. | marek's disease virus (mdv) is a highly oncogenic alphaherpesvirus that induces rapid-onset t-cell lymphoma in poultry. the complete genome of the avirulent vaccine strain mdv-814 was cloned as an infectious bacterial artificial chromosome (bac) using an 8.8-kb fragment containing the self-designed selective marker guanosine phosphoriboxyl transferase. the recombinant virus mdv-814-bac was generated by co-transfection of a bac transfer vector and mdv-814 total dna, and was purified by eight roun ... | 2009 | 19026690 |
| marek's disease virus-induced expression of cytokine genes in feathers of genetically defined chickens. | marek's disease (md) vaccines, although effective in reducing lymphoproliferation, cannot control infectious virus production in the feather follicle epithelium (ffe) which is the site of virus shedding. therefore, we investigated marek's disease virus (mdv) replication as well as the expression of cytokine genes in feathers of mdv-infected chickens belonging to genetically defined lines (n2a or b(21)/b(21) haplotype-resistant and p2a or b(19)/b(19) haplotype-susceptible). though there was not a ... | 2009 | 19041890 |
| revaccination with marek's disease vaccines induces productive infection and superior immunity. | the most common lymphoproliferative disease in chickens is marek's disease (md), which is caused by the oncogenic herpesvirus marek's disease virus (mdv). the emergence of hypervirulent pathotypes of mdv has led to vaccine failures, which have become common and which have resulted in serious economic losses in some countries, and a revaccination strategy has been introduced in practice. the mechanism by which revaccination invokes superior immunity against md is unknown. after field trials which ... | 2009 | 19052160 |
| purification of dna from the cell-associated herpesvirus marek's disease virus for 454 pyrosequencing using micrococcal nuclease digestion and polyethylene glycol precipitation. | methods for the isolation of dna from cell-associated herpesviruses have often yielded samples contaminated with host cellular dna. because 2nd and 3rd generation nucleotide sequencers do not rely on molecular cloning of viral dna, there is a need to develop methods for isolating highly pure dna from these viruses. the cell-associated alphaherpesvirus marek's disease virus (mdv-1) was chosen as a test virus for the development of such methodologies. the genomes of six mdv-1 strains have previous ... | 2009 | 19103224 |
| effects of transferrins and cytokines on nitric oxide production by an avian lymphoblastoid cell line infected with marek's disease virus. | marek's disease virus (mdv), the causative agent of marek's disease (md), is a herpesvirus that infects poultry causing t lymphomas. although vaccination may prevent lymphomas formation, it is not known whether it controls viral replication and spreading in the environment. ovotransferrin (otrf), a member of the transferrin family, is known to exert in vitro antiviral activity in primary cultures of chicken embryo fibroblasts (cef). in addition otrf is produced by cef and by an avian lymphoblast ... | 2009 | 19133294 |
| mapping qtl affecting resistance to marek's disease in an f6 advanced intercross population of commercial layer chickens. | marek's disease (md) is a t-cell lymphoma of chickens caused by the marek's disease virus (mdv), an oncogenic avian herpesvirus. md is a major cause of economic loss to the poultry industry and the most serious and persistent infectious disease concern. a full-sib intercross population, consisting of five independent families was generated by crossing and repeated intercrossing of two partially inbred commercial white leghorn layer lines known to differ in genetic resistance to md. at the f6 gen ... | 2009 | 19144166 |
| marek's disease virus infection in the eye: chronological study of the lesions, virus replication, and vaccine-induced protection. | marek's disease virus (mdv) infection in the eye was studied chronologically after inoculating 1-day-old chickens with a very virulent mdv strain, md5. the ocular lesions could be classified as early lesions (6-11 days postinoculation [dpi]) and late lesions (26 and 56 dpi), based upon the location and severity of the lesions. the early lesions involved iris, ciliary body, and choroid layer, and were characterized by endothelial cell hypertrophy, vasculitis, and infiltration of lymphocytes (main ... | 2008 | 19166047 |
| 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 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 |
| cloning of gallid herpesvirus 3 (marek's disease virus serotype-2) genome as infectious bacterial artificial chromosomes for analysis of viral gene functions. | marek's disease virus serotype 2 (gallid herpesvirus 3) is a non-pathogenic alphaherpesvirus belonging to the mardivirus genus, used widely in live vaccines against marek's disease. although the complete genome sequence of the mdv-2 strain hprs-24 has been published, very little is known about the gene functions. as a first step for carrying out functional genomic analysis of mdv-2, the full-length genome of the mdv-2 vaccine strain sb-1 was cloned as an infectious bacterial artificial chromosom ... | 2009 | 19187788 |
| in vitro characterization of the meq proteins of marek's disease virus vaccine strain cvi988. | gallid herpesvirus 2 (gahv-2), commonly known as marek's disease virus serotype-1 (mdv-1), causes t cell lymphomas in chickens. vaccines prepared from the attenuated cvi988/rispens mdv-1 strain currently offer the best protection. although attenuated cvi988/rispens is non-oncogenic, it codes for at least two forms of the mdv oncoprotein meq, and these proteins (cvi-meq and cvi-lmeq) have not been fully characterized. here, we report that both cvi-meq proteins, like the meq protein of md5 (a very ... | 2009 | 19189855 |
| cytokine gene expression in splenic cd4(+) and cd8(+) t-cell subsets of chickens infected with marek's disease virus. | specific-pathogen free chickens were infected with the rb1b strain of marek's disease virus (mdv) and t cells from the spleens of infected as well as age-matched controls were fractionated by flow cytometry at 4, 10, and 21 days post-infection (d.p.i.). real-time quantitative reverse transcription pcr was used to assess the amount of cytokine transcripts as well as viral genes meq and glycoprotein b (gb). there was an increase in the number of cd4(+) t cells, as well as a significant increase in ... | 2009 | 19210226 |
| micrornas 221 and 222 target p27kip1 in marek's disease virus-transformed tumour cell line msb-1. | micrornas (mirnas) are a class of short rnas that function as post-transcriptional suppressors of protein expression and are involved in a variety of biological processes, including oncogenesis. several recent studies have implicated the involvement of mir-221 and mir-222 in tumorigenesis as these mirnas are upregulated in a number of cancers and affect the expression of cell cycle regulatory proteins such as the cyclin-dependent kinase (cdk) inhibitor p27(kip1). marek's disease virus (mdv) is a ... | 2009 | 19264608 |
| the marek's disease virus (mdv) protein encoded by the ul17 ortholog is essential for virus growth. | marek's disease virus type 1 (mdv-1) shows a strict dependency on the direct cell-to-cell spread for its propagation in cell culture. as mdv-1 shows an impaired nuclear egress in cell culture, we wished to address the characterization of capsid/tegument genes which may intervene in the maturation of intranuclear capsids. orthologs of ul17 are present in all herpesviruses and, in all reported case, were shown to be essential for viral growth, playing a role in capsid maturation and dna packaging. ... | 2009 | 19284966 |
| identification of an intercistronic internal ribosome entry site in a marek's disease virus immediate-early gene. | in this study, we have identified an internal ribosome entry site (ires) from the highly infectious herpesvirus marek's disease virus (mdv). the ires was mapped to the intercistronic region (icr) of a bicistronic mrna that we cloned from the mdv-transformed cd4(+) t-cell line msb-1. the transcript is a member of a family of mrnas expressed as immediate-early genes with two open reading frames (orf). the first orf encodes a 14-kda polypeptide with two n-terminal splice variants, whereas the secon ... | 2009 | 19297480 |
| differential expression of micrornas in marek's disease virus-transformed t-lymphoma cell lines. | micrornas (mirnas) are increasingly recognized to play crucial roles in regulation of gene expression in different biological events, including many sporadic forms of cancer. however, despite the involvement of several viruses in inducing cancer, only a limited number of studies have been carried out to examine the mirna expression signatures in virus-induced neoplasia, particularly in herpesvirus-induced tumours where virus-encoded mirnas also contribute significantly to the mirnome of the tumo ... | 2009 | 19297609 |
| micrornas of gallid and meleagrid herpesviruses show generally conserved genomic locations and are virus-specific. | many herpesviruses, including marek's disease viruses (mdv1 and mdv2), encode micrornas. in this study, we report micrornas of two related herpesviruses, infectious laryngotracheitis virus (iltv) and herpesvirus of turkeys (hvt), as well as additional mdv2 micrornas. the genome locations, but not microrna sequences, are conserved among all four of these avian herpesviruses. most are clustered in the repeats flanking the unique long region (i/tr(l)), except in iltv which lacks these repeats. two ... | 2009 | 19328516 |
| [construction of a recombinant hvt virus expressing the ha gene of avian influenza virus h5n1 via rde/et recombination system]. | in recent years,manipulation of large herpesvirus genomes has been facilitated by using bacterial artificial chromosome (bac) vectors. we have previously reported the construction of the bac clones (hvt bacs) of herpesvirus of turkey (hvt). with these bac clones in hand,we manipulated the genome of hvt by utilizing red/et recombination system, and developed a biologically safe live vaccine based on the hvt bacs. | 2009 | 19388268 |
| novel micrornas (mirnas) encoded by herpesvirus of turkeys: evidence of mirna evolution by duplication. | herpesviruses account for 134 out of the 140 virus-encoded micrornas (mirnas) known today. here we report the identification of 11 novel mirnas encoded by herpesvirus of turkey (hvt), a virus used as a live vaccine in poultry against the highly oncogenic marek's disease virus type 1. ten of these mirnas were clustered together within the repeat long region of the viral genome, demonstrating some degree of positional conservation with other mardiviruses. close sequence and phylogenetic relationsh ... | 2009 | 19403687 |
| factors influencing the attenuation of serotype 1 marek's disease virus by serial cell culture passage and evaluation of attenuated strains for protection and replication. | this study was carried out to better understand factors that influenced the process of attenuation of marek's disease (md) virus by serial passage in cell cultures. three virulent (v) pathotype and three very virulent plus (vv+) pathotype strains were passed by three techniques up to 131 times, and the passage level at attenuation was determined. the 18 attenuated or partially attenuated viruses were evaluated for protection against challenge with virulent md virus, and the virus load (latent in ... | 2009 | 19432005 |
| detection and quantitation of fowl adenovirus genome by a real-time pcr assay. | the purpose of the study was to develop a highly sensitive real-time polymerase chain reaction (pcr) assay to detect and quantitate fowl adenovirus (fadv) dna in chicken tissues, using fadv-9 as a model. the assay had a dynamic range of 7 logs and minimum detection limit of 9.4 viral genome copies. it was shown to be highly specific, as tissues from uninfected chickens and other viral genomes, such as those of marek's disease virus, fowlpox virus and infectious laryngotracheitis virus did not pr ... | 2009 | 19442846 |
| [kinase domain analysis of mdv-1 cvi988/rispens ul13 and preferred codon fragments expression in escherichia coli]. | to find catalytic center of mdv-1 ul13 and express it in vitro to investigate the function of ul13 kinase. | 2009 | 19445169 |
| marek's disease virus phosphorylated polypeptide pp38 alters transcription rates of mitochondrial electron transport and oxidative phosphorylation genes. | two splice variants of the marek's disease virus phosphorylated polypeptide (pp)38 were previously identified in the quail cell line qtp32 expressing pp38 under the control of an inducible promoter. we developed qt35-derived cell lines expressing these splice variants or full length pp38 with the splice acceptor sites mutated to further elucidate the role of pp38. only induction of full length pp38 resulted in an increase in mitochondrial succinate dehydrogenase activity compared to non-induced ... | 2009 | 19472043 |
| interaction of marek's disease virus oncoprotein meq with heat-shock protein 70 in lymphoid tumour cells. | marek's disease virus (mdv) is a highly oncogenic alphaherpesvirus that induces the rapid onset of t-cell lymphomas in poultry. the mdv-encoded oncoprotein meq plays an important role in oncogenicity, as its deletion abolishes the ability of the virus to induce tumours. it has been shown previously that meq oncogenicity is linked to its interaction with c-terminal binding protein 1 (ctbp), a property also shared by other virus-encoded oncoproteins such as adenovirus e1a and epstein-barr virus eb ... | 2009 | 19494050 |
| mdv-1 vp22: a transporter that can selectively deliver proteins into cells. | the tegument protein vp22 of marek's disease virus (mdv) was previously shown to be able to travel between cells. to further characterize the transport property of vp22 and assess whether it can be used for protein delivery, we investigated the subcellular localization of vp22 fused to five heterologous proteins, including green fluorescent protein, nucleoprotein of avian influenza virus, bovine ifn-gamma, f protein of newcastle disease virus and vp2 protein of infectious bursa disease virus. th ... | 2009 | 19495935 |
| microarray analysis of host immune responses to marek's disease virus infection in vaccinated chickens. | marek's disease (md) is a commercially important disease of chickens caused by md virus (mdv). although avirulent mdv strains have been used for vaccination to prevent md outbreaks, the protective mechanism of the vaccine has not been elucidated. in this study, a comprehensive transcriptional analysis using microarray was conducted in mdv-infected chickens with and without vaccination at 7 and 21 days post-infection (dpi). the data suggested that the expression of t cell receptor (tcr) 1-related ... | 2009 | 19498286 |
| retroviral delivery of rna interference against marek's disease virus in vivo. | the process of rna interference (rnai) has been exploited in cultured chicken cells and in chick embryos to assess the effect of specific gene inhibition on phenotypes related to development and disease. we previously demonstrated that avian leukosis virus-based retroviral vectors are capable of delivering effective rnai against marek's disease virus (mdv) in cell culture. in this study, similar rnai vectors are shown to reduce the replication of mdv in live chickens. retroviral vectors were int ... | 2009 | 19531706 |
| analyses of the spleen proteome of chickens infected with marek's disease virus. | marek's disease virus (mdv), which causes a lymphoproliferative disease in chickens, is known to induce host responses leading to protection against disease in a manner dependent on genetic background of chickens and virulence of the virus. in the present study, changes in the spleen proteome at 7, 14 and 21 days post-infection in response to mdv infection were studied using two-dimensional polyacrylamide gel electrophoresis. differentially expressed proteins were identified using one-dimensiona ... | 2009 | 19540544 |
| molecular characterization of the genome of duck enteritis virus. | the genomic sequence of a strain of duck enteritis virus (dev) was determined and analyzed in this study. the size of its genome is 158,091 bp in length and the genome is predicted to encode 78 putative proteins and resembles the members of the alphaherpesvirinae in genomic organization and gene composition. the genome of the virus is composed of a unique long (ul) region, a unique short (us) region, a unique short internal repeat (irs) region and a unique short terminal repeat (trs) region. its ... | 2009 | 19595405 |
| cytokine gene expression in splenic cd4+ and cd8+ t cell subsets of genetically resistant and susceptible chickens infected with marek's disease virus. | t cells from the spleens of b(19)/b(19) and b(21)/b(21) chickens infected with mdv jm-16 strain were fractionated by flow cytometry at 4, 10, 21 days post infection (d.p.i.). the expression of cytokine and viral genes (meq and glycoprotein b (gb)) was measured by real-time rt-pcr. it was determined that cd4(+) and cd8(+) t cells had both become infected with marek's disease virus (mdv) in both chicken lines. there was significantly higher expression of meq in cd4(+) t cells compared to cd8(+) t ... | 2009 | 19615758 |
| herpesviruses--a zoonotic threat? | herpesviruses are highly host specific and share a long synchronous evolution with their hosts. only in rare cases, species barriers fall and allow animal to human or human to animal transmission. among the zoonotic herpesviruses, cercopithecine herpesvirus 1 is the most significant and can be transmitted from macaques to human. conversely, human herpesvirus 1 is capable of causing severe disease in primates. besides those two examples, there are several herpesviruses with a certainly limited or ... | 2010 | 19616388 |
| [comparision of pathogenicity and horizontal transmission ability between recombinant marek's disease virus field strain with rev-ltr and a very virulent reference strain]. | gx0101 is a recombinant field strain of marek's disease virus (mdv) with a long terminal repeat (ltr) insert from reticuloendotheliosis virus, a chicken retrovirus. in this study, gx0101 strain was compared to a very virulent reference strain md5 for their pathogenicity and transmission ability. | 2009 | 19621645 |
| latency of marek's disease virus (mdv) in a reticuloendotheliosis virus-transformed t-cell line. i: uptake and structure of the latent mdv genome. | marek's disease virus (mdv) is an acute transforming alphaherpesvirus of chickens that causes marek's disease. during the infection of chickens, mdv establishes latency in cd4+ (t-helper) cells, which are also the target of transformation. the study of mdv latency has been limited to the use of mdv tumor-derived cell lines or blood cells isolated from chickens during presumed periods of latent infection. in 1992 pratt et al. described the uptake of the mdv genome by a reticuloendotheliosis-trans ... | 2009 | 19630217 |
| latency of marek's disease virus (mdv) in a reticuloendotheliosis virus-transformed t-cell line. ii: expression of the latent mdv genome. | marek's disease virus (mdv) is an alphaherpesvirus of chickens that causes the paralysis and rapid lymphoma formation known as marek's disease. mdv establishes latent infection in activated cd4+ t-cells, and these cells are also the target for transformation. mdv latency has been studied using mdv lymphoma-derived cell lines and t-cells isolated from infected chickens. each of these models has limitations because mdv-transformed cell lines require the use of oncogenic viruses; conversely, pools ... | 2009 | 19630218 |
| a deletion within glycoprotein l of marek's disease virus (mdv) field isolates correlates with a decrease in bivalent mdv vaccine efficacy in contact-exposed chickens. | we examined the functional role of a naturally occurring deletion within the glycoprotein l (gl) gene of marek's disease virus (mdv) field isolates. we previously showed that this mutation incrementally increased the virulence of an mdv in contact-exposed spf leghorn chickens, when chickens shedding this virus were co-infected with herpesvirus of turkeys (hvt). in our present study, we examined this mutation using two stocks of the very virulent plus (vv+)mdv strain tk, one of which harbored thi ... | 2009 | 19630238 |
| increased dna damage and oxidative stress in chickens with natural marek's disease. | oxidative stress contributes to the accumulation of genomic abnormalities, prevents cellular apoptosis, and also mediates immunosuppression resulting in tumor formation. marek's disease provides excellent opportunities for the study of herpesvirus-induced tumors both in experimental- and natural conditions. the aim of this study was to examine the effects of marek's disease (md) on basal levels of dna strand breaks and on the oxidative-antioxidative status of chickens with md. white-lohmann hens ... | 2010 | 19647879 |
| [marek's disease virus encoded mirnas--an update review]. | 2009 | 19678572 | |
| homodimerization of the meq viral oncoprotein is necessary for induction of t-cell lymphoma by marek's disease virus. | marek's disease virus (mdv) is a lymphotropic alphaherpesvirus that induces fatal rapid-onset t-cell lymphomas in chickens, its natural host. the mdv-encoded nuclear oncoprotein meq is essential for lymphomagenesis and acts as a regulator of transcription. meq has structural features, including a basic domain adjacent to a leucine zipper motif (b-zip), that suggest it is related to the jun/fos family of transcription factors. via the leucine zipper, meq can form homodimers or heterodimerize with ... | 2009 | 19692466 |
| a gammaherpesvirus ubiquitin-specific protease is involved in the establishment of murine gammaherpesvirus 68 infection. | murine gammaherpesvirus 68 (mhv-68) contains a ubiquitin (ub)-specific cysteine protease (usp) domain embedded within the large tegument protein orf64, as do all other herpesviruses. the biological role of this protease is still unclear, but for the alphaherpesvirus marek's disease virus, its usp is involved in t-cell lymphoma formation. we here study the role of the mhv-68 usp, encoded by orf64. by constructing a mutant virus with a single cysteine-to-alanine replacement in the active site of o ... | 2009 | 19706716 |
| induction of innate host responses in the lungs of chickens following infection with a very virulent strain of marek's disease virus. | the natural route of entry of marek's disease virus (mdv) is via the respiratory system. however, little is known about host-virus interactions in the lungs. the objective of the present study was to examine mdv replication and induction of innate host responses in the lungs of chickens infected through inhalation. replication of mdv in lungs was detectable as early as 12 hours post-infection (hpi). the expression of toll-like receptor (tlr)3 and tlr7 genes was enhanced in response to mdv infect ... | 2009 | 19733379 |
| [differentiation of recombinant adenoviruses expressed mdv-1 vp22 subcellular localization pattern]. | to study the transduction and localization mechanism of marek's disease virus serotype 1 (mdv-1) cvi988 vp22 in different cells. | 2009 | 19737462 |
| ty3 nuclear entry is initiated by viruslike particle docking on glfg nucleoporins. | yeast retrotransposons form intracellular particles within which replication occurs. because fungal nuclear membranes do not break down during mitosis, similar to retroviruses infecting nondividing cells, the cdna produced must be translocated through nuclear pore complexes. the saccharomyces cerevisiae long terminal repeat retrotransposon ty3 assembles its gag3 and gag3-pol3 precursor polyproteins into viruslike particles in association with perinuclear p-body foci. these perinuclear clusters o ... | 2009 | 19759143 |
| the 5' leader of the mrna encoding the marek's disease virus serotype 1 pp14 protein contains an intronic internal ribosome entry site with allosteric properties. | we demonstrate the presence of a functional internal ribosome entry site (ires) within the 5' leader (designated 5l) from a variant of bicistronic mrnas that encode the pp14 and rlorf9 proteins from marek's disease virus (mdv) serotype 1. transcribed as a 1.8-kb family of immediate-early genes, the mature bicistronic mrnas have variable 5' leader sequences due to alternative splicing or promoter usage. consequently, the presence or absence of the 5l ires in the mrna dictates the mode of pp14 tra ... | 2009 | 19793814 |
| bg1 has a major role in mhc-linked resistance to malignant lymphoma in the chicken. | pathogen selection is postulated to drive mhc allelic diversity at loci for antigen presentation. however, readily apparent mhc infectious disease associations are rare in most species. the strong link between mhc-b haplotype and the occurrence of virally induced tumors in the chicken provides a means for defining the relationship between pathogen selection and mhc polymorphism. here, we verified a significant difference in resistance to gallid herpesvirus-2 (gahv-2)-induced lymphomas (marek's d ... | 2009 | 19805366 |
| mhc expression on spleen lymphocyte subsets in genetically resistant and susceptible chickens infected with marek's disease virus. | resistance and susceptibility to marek's disease (md) are strongly influenced by the chicken major histocompatibility complex (mhc). in this study, splenic lymphocytes from md-resistant and md-susceptible chickens of three mhc genotypes (b21/b21, b19/b21, and b19/b19) were analyzed by flow cytometry for mhc surface expression. in the spleen, constitutive mhc class i surface expression was found to be highest in homozygous b19, lowest in homozygous b21, and intermediate in heterozygous b19/b21 an ... | 2009 | 19811089 |
| full genome sequences of two reticuloendotheliosis viruses contaminating commercial vaccines. | reticuloendotheliosis virus (rev) fragments are a common contaminant in some commercial vaccines such as fowl poxvirus (fpv) and marek's disease virus. however, only those strains integrating or containing a near-intact rev provirus are more likely to cause problems in the field. we confirm here, by pcr assays and animal experiments, that vaccines against fpv and herpes virus of turkeys were contaminated with full genome sequences of rev. further, we determined the complete proviral sequence of ... | 2009 | 19848070 |
| establishment of an aerosol-based marek's disease virus infection model. | marek's disease virus (mdv), which is the causative agent of marek's disease (md), is shed by infected chickens and transmitted to other chickens through the respiratory route. experimental reproduction of md has been commonly done either by intra-abdominal inoculation of cell-associated mdv or by exposure to mdv-infected 'seeder' chickens. the former method does not mimic the natural route of mdv infection, whereas the latter method suffers from lack of uniformity in the timing and amount of vi ... | 2009 | 19848077 |
| pathological and immunohistochemical study of chickens with co-infection of marek's disease virus and chicken anaemia virus. | chicken anaemia virus (cav) is the most important confounding pathogen in marek's disease virus (mdv) infection. the effect of cav co-infection at 4 weeks of age after inoculation of virulent mdv (vmdv, ks strain) or very virulent mdv (vvmdv, md/5 strain) in 1-day-old chicks was investigated by pathological and immunohistochemical studies. cav increased the mortality rates induced by vmdv or vvmdv. the packed cell volume was reduced significantly in vmdv-cav infection; however, no reduction or n ... | 2009 | 19937536 |
| detection of virulent marek's disease virus in poultry in india. | marek's disease virus (mdv) isolated from poultry flocks in three states of india was monitored for the virus occurrence in the field. the mdv genome was isolated from feather follicles, spleen, and liver of the chicken (173 samples). twenty two samples were positive for mdv genome in pcr and belonged to the serotype 1. the sequencing of meq gene of 11 samples revealed that nucleotide sequences of the isolate ind-ka-01-06 was similar to the very virulent mdv, strain rb-1b. in situ hybridization ... | 2009 | 19941389 |
| comparative evaluation of vaccine efficacy of recombinant marek's disease virus vaccine lacking meq oncogene in commercial chickens. | marek's disease virus (mdv) oncogene meq has been identified as the gene involved in tumorigenesis in chickens. we have recently developed a meq-null virus, rmd5 delta meq, in which the oncogene meq was deleted. vaccine efficacy experiments conducted in avian disease and oncology laboratory (adol) 15i(5) x 7(1) chickens vaccinated with rmd5 delta meq virus or an adol preparation of cvi988/rispens indicated that rmd5 delta meq provided superior protection than cvi988/rispens when challenged with ... | 2010 | 19941987 |
| the construction and characterization of the bi-directional promoter between pp38 gene and 1.8-kb mrna transcripts of marek's disease viruses. | marek's disease virus (mdv) has a bi-directional promoter between pp38 gene and 1.8-kb mrna transcripts. by sequencing for the promoters from 8 different strains (cvi988, 814, ga, jm, md5, g2, rb1b and 648a), it is found, comparing with the other 7 mdv strains, cvi988 has a 5-bp (from -628 to -632) deletion in this region, which caused a sp1 site destroyed. in order to analysis the activity of the promoter, the complete bi-directional promoters from ga and cvi988 were, respectively, cloned into ... | 2009 | 19948021 |
| early replication in pulmonary b cells after infection with marek's disease herpesvirus by the respiratory route. | abstract natural infection with marek's disease virus occurs through the respiratory mucosa after chickens inhale dander shed from infected chickens. the early events in the lung following exposure to the feather and squamous epithelial cell debris containing the viral particles remain unclear. in order to elucidate the virological and immunological consequences of mdv infection for the respiratory tract, chickens were infected by intratracheal administration of infective dander. differences bet ... | 2009 | 19951180 |
| [mutational analysis of meq, rlorf4, rlorf12 and 132bpr genes of epidemic marek's disease virus strains highly passaged on chicken embryo fibroblast]. | recently, much work has been devoted to study md-induced oncogenesis and the genes involved in this process. among many genes in the mdv genome, several genes such as meq, rlorf4, rlorf12, and 132bpr have been considered recently associated with virulence of mdv. in this paper, primers of meq, rlorf4, rlorf12 and 132bpr genes were designed and synthesized, based on the published whole genome sequence of mdv strain ga. the genes of meq, rlorf4 and rlorf12 from four chinese epidemic mdv strains hi ... | 2009 | 19954114 |
| [evaluation of the pathogenicity of a field isolate of marek's disease virus integrated with retroviral long terminal repeat sequence]. | the pathogenicity of a field isolate of marek's disease virus (mdv) named gxy2 integrated with retroviral long terminal repeat (ltr) sequence from a chicken with md tumors was evaluated. experimental chickens were divided into group a, b, c, d and e. the later four groups were vaccinated on one-day-old with cvi988/rispens for group b and d, with hvt for group c and e, while group a was taken as no-vaccinated control. on 8-day-old, group a, b and c were challenged with gxy2 by intra-abdominal inj ... | 2009 | 19954115 |
| functional evaluation of the role of reticuloendotheliosis virus long terminal repeat (ltr) integrated into the genome of a field strain of marek's disease virus. | mdv-gx0101 is a field strain of marek's disease virus with a naturally occurring insertion of the reticuloendotheliosis virus (rev) ltr fragment. in order to study the biological properties of rev-ltr insertion in the mdv genome, we constructed a full-length infectious bac clone of mdv-gx0101 strain and deleted the ltr sequences by bac mutagenesis. the pathogenic properties of the ltr-deleted virus were evaluated in infected spf birds. the study demonstrated that the ltr-deleted virus had a stro ... | 2010 | 19962172 |
| development of a primer-probe energy transfer based real-time pcr for detection of marek's disease virus. | a real-time pcr assay, which enables simultaneous detection and differentiation of all three serotypes of marek's disease virus, without the need for post-pcr sequencing, has been developed. the assay is based on the primer-probe energy transfer real-time pcr, which has a relatively high tolerance towards point mutations in the probe region. the pcr is followed by a probe melting point analysis, which enables confirmation of identity of amplicon and differentiation of serotypes. the assay target ... | 2010 | 20026120 |
| molecular and biological characterization of a marek's disease virus field strain with reticuloendotheliosis virus ltr insert. | a marek's disease virus (mdv) field strain designated gx0101 was isolated from a layer flock and confirmed to be a recombinant virus with an insert of a long terminal repeat (ltr) from the reticuloendotheliosis virus (rev). a chimeric molecule containing an rev-ltr insert of 539 bp and its flanking sequences from mdv was amplified and sequenced. an rev-ltr downstream from the internal repeat short (irs) region has 77.4-98.6% homology to seven rev field strains isolated from different avian speci ... | 2010 | 20043197 |