Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| effect of reticuloendotheliosis virus and infectious bursal disease virus on marek's disease herpesvirus latency. | birds infected with reticuloendotheliosis virus (rev) were exposed to marek's disease virus (mdv) to determine if the establishment of mdv latency was affected by rev-induced immunosuppression, while other chickens, already latently infected with mdv, were challenged with rev or infectious bursal disease virus (ibdv) to determine if the consequent immunosuppression caused a return to cytolytic infection. immunosuppression was assessed by in vitro mitogen stimulation assays with spleen cells. lat ... | 1989 | 18679859 |
| detection of reticuloendotheliosis virus infection using the polymerase chain reaction. | the polymerase chain reaction (pcr) was shown to be a sensitive and useful method for detection of infection by members of the group of avian reticuloendotheliosis virus (rev). genomic dna extracted from chick embryo fibroblasts (cefs), blood and tumours of chickens experimentally infected with the spleen necrosis virus (snv) strain of rev was used as the target for chain elongation. deoxyoligonucleotide primers that encompass a portion of the unique 3', repeat and unique 5' region of the long t ... | 1993 | 18671039 |
| preparation and characterization of chicken intraepithelial leukocytes. | intraepithelial leukocytes (iels) form an important component of the intestinal immune system. several methods of preparing chicken iels were compared for cell yield, cell populations, and functional activity against a natural killer (nk)-susceptible lymphoblastoid cell line (lscc-rp9). in addition, an attempt was made to immortalize iels by infection with reticuloendotheliosis virus (rev) for use in cell-trafficking studies. intestinal fragments were incubated in 5 mm dl-dithiothreitol at 41 de ... | 1993 | 18671036 |
| protection against reticuloendotheliosis virus-strain t tumours is associated with jmv-1 culture supernatant-enhanced natural killer cell activity. | one-day-old chicks were inoculated intraperitoneally with cell-free jmv-1 culture supernatant and were subsequently challenged with a lethal dose of recc-cu60 tumour cells at either 7 or 12 days of age. a significant reduction in mortality was evidenced in chicks that had been inoculated with jmv-1 culture supernatant prior to recc-cu60 tumour cell challenge at 12 days of age, compared with all other treatment groups. reducing the serum content of jmv-1 culture medium or changing the base medium ... | 1992 | 18670954 |
| some observations on naturally occurring neoplasms of domestic fowls in the state of victoria, australia (1977-87). | in the 10 years to november 1987, 33 different types of naturally occurring neoplasms were diagnosed in 2281 domestic fowls submitted for necropsy examination. the most prevalent type was lymphoma (1825/2281 = 80%) including two cases in chickens from a flock free from marek's disease virus, exogenous avian leukosis viruses and reticuloendotheliosis virus; the remaining lymphomas were diagnosed on gross and/or histological criteria as marek's disease (1069) or lymphoid leukosis (754). of the non ... | 1996 | 18645870 |
| enhancement of reticuloendotheliosis virus-induced bursal lymphomas by serotype 2 marek's disease virus. | the effect of serotype 2 and 3 marek's disease virus (mdv) vaccines on the pathogenesis of reticuloendotheliosis virus (rev)-induced bursal and non-bursal lymphomas was examined in chickens of rprl lines 15i(5) x 7(1) and 6(3) x 0, respectively. at hatch, chickens were vaccinated with strain 301b/1 of serotype 2 mdv or strain fc126 of turkey herpesvirus (hvt), a serotype 3 mdv and inoculated with spleen necrosis virus (snv), a non-defective strain of rev. in another experiment, bursas from 14-we ... | 1996 | 18645839 |
| an outbreak of lymphomas in commercial broiler breeder chickens vaccinated with a fowlpox vaccine contaminated with reticuloendotheliosis virus. | gross and microscopic examinations of affected tissues from chickens of two commercial broiler breeder flocks aged 27 and 31 weeks revealed lesions of visceral lymphomas with bursal involvement in some chickens. reticuloendotheliosis virus (rev), but not avian leukosis virus (alv), was isolated from blood of affected chickens. furthermore, dna extracted from tumours tested positive for rev, but not for alv or marek's disease virus by polymerase chain reaction (pcr) test. attempts to determine th ... | 1996 | 18645835 |
| use of the polymerase chain reaction for the diagnosis of natural infection of chickens and turkeys with marek's disease virus and reticuloendotheliosis virus. | marek's disease (md) is a highly contagious lymphoproliferative disease of chickens caused by a herpesvirus, while reticuloendotheliosis (rev) virus is an avian c-type retrovirus that causes bursal and nonbursal lymphomas which often closely resemble mdv lymphomas. to provide a rapid and sensitive means of diagnosing and differentiating between these two neoplastic conditions, we have applied the pcr. the primers chosen to detect mdv sequences flank the 132 bp tandem repeat of the bamhi-h fragme ... | 1995 | 18645767 |
| detection of reticuloendotheliosis virus by immunohistochemistry and in situ hybridization in experimentally infected japanese quail embryos and archived formalin-fixed and paraffin-embedded tumours. | reticuloendotheliosis virus (rev) infection can result in immunosuppression, a runting syndrome, high mortality, acute reticulum cell neoplasia, or t-cell and/or b-cell lymphomas, in a variety of domestic and wild birds. histopathological changes in rev infection are not sufficient to differentiate it from avian lymphoid leukosis and marek's disease, and currently there are no available in situ diagnostic methods for detection of active rev presence in pathologic specimens. to develop immunohist ... | 2008 | 18622864 |
| [reticuloendotheliosis virus infection in ducks--an epidemiological studies]. | to study the epidemiological status of reticuloendotheliosis virus (rev) infection in ducks. | 2008 | 18590239 |
| field isolates of fowlpox virus contaminated with reticuloendotheliosis virus. | the polymerase chain reaction (pcr) method was used to examine samples from field cases of fowlpox for the presence of reticuloendotheliosis virus (rev). the s-strain fowlpox vaccine, known to be contaminated with rev, served as a positive control. fowlpox virus was grown from field samples and vaccines by inoculation of embryonated hen eggs by the chorioallantoic membrane (cam) route. dna was extracted from the cam lesions and examined for rev proviral sequences using primers specific for the l ... | 1998 | 18483965 |
| replication of non-defective reticuloendotheliosis viruses in the avian embryo assayed by pcr and immunofluorescence. | congenital transmission of reticuloendotheliosis virus (rev) is known to occur when one of the parents in either tolerantly infected or viraemic; however little attention has been paid to replication of the virus within the embryo itself. in this study five non-defective and one replication-defective strain of rev were inoculated into the yolk sac of 6-day-old embryonated eggs. with the exception of one non-defective strain, the others induced embryonic deformation or lesions that were apparent ... | 1997 | 18483929 |
| occurrence of reticuloendotheliosis in chinese partridge. | two commercial flocks of chinese partridge experienced increased mortality associated with a wasting disease at 120-day old in june 2006. postmortem examination of dead chickens consistently showed visceral tissues mainly proventriculus, liver and spleen were diffuse enlargement. microscopic examination revealed masses of immature lymphocytes with frequent mitotic figures were seen in various tissues including proventriculus, liver, spleen, kidney, heart, lung, thymus and intestine. reticuloendo ... | 2007 | 18176029 |
| [pathogenicity and genomic sequence comparison of a chicken infectious anemia virus field isolate]. | a field strain c14 of chicken infectious anemia virus (cav) was isolated from a 14 day-old broiler flock with growth runting syndromes. antibody reactions to inactivated vaccines to avian influenza viruses (aiv) were suppressed in spf chickens inoculated with c14 strain cav at 1 day-old. also c14 strain cav and reticuloendotheliosis virus demonstrated a synergism in immunosuppression when chickens were infected with both virus. the viral genomic dna was amplified by pcr in 3 overlapped fragments ... | 2007 | 18062269 |
| detection and differentiation of re-emerging fowlpox virus (fwpv) strains carrying integrated reticuloendotheliosis virus (fwpv-rev) by real-time pcr. | current strains of fowlpox virus (fwpv) carrying circulating reticuloendotheliosis virus (fwpv-rev) sequence are becoming more pathogenic to poultry. this is evidenced by the fact that vaccination with current available fwpv vaccines provides limited protection against them. to characterize rev insertions in a collection of both older and more recent field isolates, we developed three different types of adjacent oligoprobes and primer sets from specific genomic locations of fwpv and rev: rev-env ... | 2008 | 17913400 |
| epidemiological and pathological studies of subgroup j avian leukosis virus infections in chinese local "yellow" chickens. | epidemiological, pathological and molecular studies indicate that subgroup j avian leukosis virus (alv-j) infections are widely spread in "yellow chickens" of local breeds in china. alv-j induced tumour mortality and the serological conversion rates to alv-j were very high in some breeder flocks. typical myelocytomatosis was demonstrated not only in livers, spleens, kidneys, and sternums, as in white meat-type chickens, but also in thymuses and the bursa of fabricius. especially, severe myeloid ... | 2007 | 17497335 |
| pathogenicity and transmission of reticuloendotheliosis virus isolated from endangered prairie chickens. | the pathogenicity and transmission of a field isolate of reticuloendotheliosis virus (rev) was studied using an experimental model in japanese quail. oncogenicity was also evaluated after inoculations in chickens and turkeys. the original rev (designated apc-566) was isolated from attwater's prairie chickens (tympanuchus cupido attwateri), an endangered wild avian species of the southern united states. the transmissibility of the rev isolate was studied in young naive japanese quail in contact w ... | 2007 | 17461264 |
| rna helicase a interacts with divergent lymphotropic retroviruses and promotes translation of human t-cell leukemia virus type 1. | the 5' untranslated region (utr) of retroviruses contain structured replication motifs that impose barriers to efficient ribosome scanning. two rna structural motifs that facilitate efficient translation initiation despite a complex 5' utr are internal ribosome entry site (ires) and 5' proximal post-transcriptional control element (pce). here, stringent rna and protein analyses determined the 5' utr of spleen necrosis virus (snv), reticuloendotheliosis virus a (rev-a) and human t-cell leukemia v ... | 2007 | 17426138 |
| effects of reticuloendotheliosis virus and marek's disease virus infection and co-infection on ifn-gamma production in spf chickens. | two experiments were used to examine the potential role of ifn-gamma in chickens infected with reticuloendotheliosis virus (rev) and marek's disease virus (mdv). first, chickens were infected with rev and/or mdv at 5 days of age and examined from 3 to 50 days post-infection (dpi). in rev+mdv co-infection chickens, ifn-gamma elisa demonstrated a 3-fold increase at 7 dpi compared to the controls, while rev alone caused a 5-fold increase, the ifn-gamma levels peaked, and then gradually decreased. i ... | 2007 | 17339769 |
| experimental infection of attwater's/greater prairie chicken hybrids with the reticuloendotheliosis virus. | reticuloendotheliosis virus (rev), a common pathogen of poultry, has been associated with runting and neoplasia in an endangered subspecies of grouse, the attwater's prairie chicken. the pathogenesis of rev infection was examined in experimentally infected prairie chickens. three groups of four attwater's/greater prairie chicken hybrids were infected intravenously with varying doses (tissue culture infective dose [tcid50], 200, 1000, and 5000) of a prairie chicken-isolated rev. a fourth group of ... | 2006 | 17274303 |
| enzootic reticuloendotheliosis in the endangered attwater's and greater prairie chickens. | reticuloendotheliosis (re) in captive greater prairie chickens (gpc, tympanuchus cupido pinnatus) and attwater's prairie chickens (apc, tympanuchus cupido attwateri) was first reported in 1998. re is caused by avian reticuloendotheliosis virus (rev), an oncogenic and immunosuppressive retrovirus infecting multiple species of wild and domestic birds. during august 2004 through may 2006 a captive population of prairie chickens was affected simultaneously with a neoplastic condition and also avian ... | 2006 | 17274288 |
| serological and virological surveys of reticuloendotheliosis in chickens in taiwan. | reticuloendotheliosis virus (rev) is widespread in the world. no related data has been reported in taiwan. to determine the rev infection status, antibody determination and virus isolation were performed on chickens in taiwan. the results revealed that serological flock prevalence for the rev antibody reached 92.8% (39/42) amongst breeders (> 16 weeks old). two different rev isolates were identified by reverse transcriptase-polymerase chain reaction, electron microscopic, immunofluorescent, and ... | 2006 | 17213700 |
| full genome sequence and some biological properties of reticuloendotheliosis virus strain apc-566 isolated from endangered attwater's prairie chickens. | reticuloendotheliosis virus (rev) causes runting, high mortality, immunosuppression, and chronic neoplasia associated with t and/or b cell lymphomas in a variety of domestic and wild birds, including attwater's prairie chickens (apc) (tympanuchus cupido attwateri). the complete proviral sequence of a recent rev isolate from apc (rev apc-566) was determined. this virus was isolated from an apc maintained in captivity in a reproduction program intended to avoid its extinction. rev apc-566 was dete ... | 2007 | 17098316 |
| detection of reticuloendotheliosis virus in live virus vaccines of poultry. | in vitro and in vivo assays have been used for the detection of reticuloendotheliosis virus (rev) in live virus vaccines of poultry. the presence of rev is confirmed by the demonstration of viral antigen or provirus in chicken embryo fibroblasts (cefs) or in specific-pathogen-free chickens inoculated with vaccine. using rev polyclonal or monoclonal antibodies, cefs inoculated with vaccines can be examined for rev by immunofluorescence or immunoperoxidase staining methods. cell lysates from such ... | 2006 | 17058506 |
| isolation and molecular biological investigations of avian poxviruses from chickens, a turkey, and a pigeon in croatia. | in the last 3 yr, several outbreaks of avian poxviruses (apvs) have been observed in different parts of croatia. four strains of apvs, from chickens, a pigeon, and a turkey, were isolated from cutaneous lesions by inoculation onto the chorioallantoic membranes (cam) of 12-day-old specific-pathogen-free chicken embryos. the resulting proliferative cam lesions contained eosinophilic cytoplasmic inclusion bodies. the characteristic viral particles of poxvirus were detected in the infected cam and a ... | 2006 | 17039847 |
| [sequence analysis of integration sites of reticuloendotheliosis virus ltr in fowlpox vaccine virus genomes]. | by use of genomic dna prepared from 5 fowlpox virus (fpv) vaccines made in china (from shandong, beijing, liaoning, zhejing and shanghai respectively) as the templates, reticuloendotheliosis virus (rev) ltr was amplified in pcr with a pair of primers synthesized according to the sequences flanking the integrated rev-5'ltr in fpv genomes published in us and australia. sequence analysis indicated that the rev-5'ltr integration sites in genomes of all 5 chinese pfv vaccine products were identical t ... | 2006 | 17037075 |
| chicken major histocompatibility complex class ii molecules of the b haplotype present self and foreign peptides. | the chicken major histocompatibility complex (mhc), or b-complex, mediates genetic resistance and susceptibility to infectious disease. for example, the b19 haplotype is associated with susceptibility to marek's disease. here, we describe the sequencing and analysis of peptides presented by b19 mhc class ii molecules. a b19/b19 b-cell line was used for the immunoaffinity purification of mhc class ii molecules, which was followed by acid elution of the bound peptides. the eluted peptides were the ... | 2006 | 16879355 |
| sarcomas and myelocytomas induced by a retrovirus related to myeloblastosis-associated virus type 1 in white leghorn egg layer chickens. | an outbreak of subcutaneous sarcomas in commercial white leghorn egg layers was observed in the northeastern united states during late 2004. subcutaneous tumors were confined to three flocks distributed in two locations and belonging to the same company. the tumors were first observed grossly by farm personnel at approximately 7 wk of age and persisted throughout the economic life of the flocks. most of the tumors observed during the growing period were present on the facial region or around the ... | 2006 | 16863068 |
| sequence analysis for the complete proviral genome of reticuloendotheliosis virus chinese strain ha9901. | the genomic dna extracted from chicken embryo fibroblast (cef) infected with a chinese field isolate ha9901 of reticuloendotheliosis virus (rev) was used as the template to amplify the rev proviral genomic cdna by pcr with 6 pairs of primers according to published sequences. six overlapping fragments were amplified, cloned into the ta vector and sequenced, including a fragment which was amplified from the circular proviral cdna and covering both 5'- and 3'-ends. the complete sequence of the whol ... | 2006 | 16704118 |
| evaluation of immune effects of fowlpox vaccine strains and field isolates. | the immune effects of fowlpox virus (fpv) field isolates and vaccine strains were evaluated in chickens infected at the age of 1 day and 6 weeks. the field isolates and the obsolete vaccine strain (fpv s) contained integrated reticuloendotheliosis virus (rev) provirus, while the current vaccine strain (fpvst) carries only rev ltr sequences. an indirect antibody elisa was used to measure the fpv-specific antibody response. the non-specific humoral response was evaluated by injection of two t-cell ... | 2006 | 16650660 |
| antigenic and genetic characterization of an avian poxvirus isolated from an endangered hawaiian goose (branta sandvicensis). | an avian poxvirus from cutaneous lesions in a hawaiian goose (branta sandvicensis) was characterized in this study. the virus was isolated by inoculation onto the chorioallantoic membranes (cams) of developing chicken embryos. cytoplasmic inclusion bodies were observed on histopathological examination of cam lesions. western blotting analysis using polyclonal antiserum against fowl poxvirus (fwpv) showed differences from fwpv, but a similar antigenic profile between hawaiian goosepox (hgp) isola ... | 2006 | 16617975 |
| phylogenetic analyses indicate little variation among reticuloendotheliosis viruses infecting avian species, including the endangered attwater's prairie chicken. | reticuloendotheliosis virus infection, which typically causes systemic lymphomas and high mortality in the endangered attwater's prairie chicken, has been described as a major obstacle in repopulation efforts of captive breeding facilities in texas. although antigenic relationships among reticuloendotheliosis virus (rev) strains have been previously determined, phylogenetic relationships have not been reported. the pol and env of rev proviral dna from prairie chickens (pc-r92 and pc-2404), from ... | 2006 | 16497405 |
| construction and characterization of a fowlpox virus field isolate whose genome lacks reticuloendotheliosis provirus nucleotide sequences. | fowlpox virus (fwpv) has been isolated from vaccinated chicken flocks during subsequent fowlpox outbreaks that were characterized by a high degree of mortality and significant economic losses. this inability of current vaccines to induce adequate immunity in poultry could be reflective of an antigenic and/or biologic distinctiveness of fwpv field isolates. in this regard, whereas an infectious reticuloendotheliosis virus (rev) provirus is present in the majority of the field viruses' genomes, on ... | 2005 | 16252496 |
| [immunogenicity of envelope glycoprotein gene of reticuloendotheliosis virus expressed in insect cell]. | a recombinant baculovirus expressing reticuloendotheliosis virus env gene was constructed with bac-to-bac baculovirus expression systems. after transfecting the recombinant virus into sf9 cells for 3 days, rev env can be detected by indirect immunofluorescence antibody assay (ifa) and western blot with specific monoclonal antibodies of rev. the oil-water emulsion vaccine was then produced using this infected sf9 cells lycates and inoculated spf chickens to validate the immunogenicity for rev. th ... | 2005 | 16245878 |
| novel criteria for the diagnosis of marek's disease virus-induced lymphomas. | several novel criteria have been tested to assist in the differential diagnosis of tumours induced by marek's disease virus (mdv) from those induced by avian leukosis virus (alv) and reticuloendotheliosis virus (rev). a collection of tumours induced by inoculation of specific strains of mdv, alv and rev, alone or in combination, were tested for quantification of mdv dna by real-time polymerase chain reaction, expression of the mdv oncogene meq, expression of several cell markers associated with ... | 2005 | 16147570 |
| distinct roles for the nf-kappab1 and c-rel transcription factors in the differentiation and survival of plasmacytoid and conventional dendritic cells activated by tlr-9 signals. | reticuloendotheliosis viral oncogene homolog/nuclear factor of kappa light polypeptide gene enhancer in b cells 1 (rel/nf-kappab) activation is a ubiquitous outcome of engaging toll-like receptors (tlrs), yet the cell-type-specific functions of this pathway in response to particular microbial signals remain poorly defined. here we show that nf-kappab1 and c-rel, rel/nf-kappab proteins induced in conventional dendritic cells (cdcs) and plasmacytoid dendritic cells (pdcs) by cytosine-phosphate-gua ... | 2005 | 16037393 |
| serological investigations of infectious bursal disease virus and reticuloendotheliosis virus infections in new zealand chickens. | 1982 | 16030899 | |
| isolation of recombinant field strains of marek's disease virus integrated with reticuloendotheliosis virus genome fragments. | two marek's disease virus (mdv) field strains were isolated from chickens with tumors independently from guangdong and guangxi provinces, and it was confirmed that there were no co-infections with reticuloendotheliosis viruses (rev) in chicken embryo fibroblast cells (cef) in indirect fluorescence antibody test (ifa) with rev-specific monoclonal antibodies. by dot blot hybridization and pcr of genomic dna of mdv-infected cef, it was indicated that ltr fragments of rev genome were integrated into ... | 2005 | 15844360 |
| insect contribution to horizontal transmission of reticuloendotheliosis virus. | the involvement of insects in reticuloendotheliosis virus (rev) transmission was examined by testing insects trapped at commercial farms and by controlled feeding experiments using mosquitoes, culex pipiens l. and house flies, musca domestica l. we established sensitive methods of rev detection, including reverse transcription-polymerase chain reaction (pcr) for rev-ltr and rev-gag genes, rev antigenemia measurements by enzyme-linked immunosorbent assay, and virus isolation in tissue cultures. a ... | 2005 | 15799521 |
| chicken primary enterocytes: inhibition of eimeria tenella replication after activation with crude interferon-gamma supernatants. | a reproducible and original method for the preparation of chicken intestine epithelial cells from 18-day-old embryos for long-term culture was obtained by using a mechanical isolation procedure, as opposed to previous isolation methods using relatively high concentrations of trypsin, collagenase, or edta. chicken intestine epithelial cells typically expressed keratin and chicken e-cadherin, in contrast to chicken embryo fibroblasts, and they increased cell surface mhc ii after activation with cr ... | 2004 | 15529984 |
| spliced spleen necrosis virus vector rna is not encapsidated: implications for retroviral replication and vector design. | rna splicing is a complex event in the retroviral life cycle and can involve multiple steps, as well as cis-acting sequences, to maintain a proper balance of spliced and unspliced viral rna for translation and encapsidation. the retroviral rna can be processed by cellular machinery and enables the removal of intronic sequences. we aimed to utilize the removal of a synthetic intron for targeted gene expression. to analyze intron removal and gene expression, we have constructed a novel self-inacti ... | 2004 | 15093186 |
| characterization of an avianpox virus isolated from an andean condor (vultur gryphus). | a novel pox virus, condorpox virus (cpv) isolated from the spleen of an andean condor (vultur gryphus) by inoculation of chorioallantoic membranes (cam) of specific pathogen free (spf) chicken embryos was compared biologically, antigenically and genetically with fowlpox virus (fpv), the type species of the genus avipoxvirus. susceptible chickens inoculated with cpv developed only mild localized lesions but were not protected against subsequent challenge with fpv. based on western blotting, in ad ... | 2003 | 14559171 |
| cell-type-specific gene delivery into neuronal cells in vitro and in vivo. | the avian retroviruses reticuloendotheliosis virus strain a (rev-a) and spleen necrosis virus (snv) are not naturally infectious in human cells. however, rev-a-derived viral vectors efficiently infect human cells when they are pseudotyped with envelope proteins displaying targeting ligands specific for human cell-surface receptors. here we report that vectors containing the gag region of rev-a and pol of snv can be pseudotyped with the envelope protein of vesicular stomatitis virus (vsv) and the ... | 2003 | 14517061 |
| prevalence of infectious diseases in ring-necked pheasant flocks in poland. | the health status of ring-necked pheasants in view of the prevalence of infectious diseases was estimated in polish pheasantries in the years 1997-2000. anatomicopathological, microbiological and serological examinations were carried out on birds derived from 26 pheasantries, including birds randomly selected from 18 flocks and sick or dead birds sent from 8 pheasantries. antibodies specific to the following viruses were detected in serum blood samples: he, ae, ap, reo, ai, adeno group 1, md, nd ... | 2003 | 14510048 |
| a novel method to analyze viral antigen-specific cytolytic activity in the chicken utilizing flow cytometry. | in order to overcome some of the main drawbacks that have emerged in the conventional assays for cytotoxic t-lymphocytes (ctls) in the chicken, a novel approach to analyze viral antigen-specific cytolytic activity utilizing flow cytometry was developed. in this method, the target cells were distinguished from the effector cells by pre-labelling them with a fluorescent dye pkh67. cell death was detected with propidium iodide which labels the dna of damaged cells. flow cytometric assay also enable ... | 2003 | 12969631 |
| molecular characterization of reticuloendotheliosis virus insertions in the genome of field and vaccine strains of fowl poxvirus. | evidence of the widespread occurrence of reticuloendotheliosis virus (rev) sequence insertions in fowl poxvirus (fpv) genome of field isolates and vaccine strains has increased in recent years. however, only those strains carrying a near intact rev provirus are more likely to cause problems in the field. detection of the intact provirus or rev protein expression from fpv stocks has proven to be technically difficult. the objective of the present study was to evaluate current and newly developed ... | 2003 | 12887193 |
| detection of specific reticuloendotheliosis virus sequence and protein from rev-integrated fowlpox virus strains. | the detection is described of reticuloendotheliosis virus (rev) protein in tissue culture of chicken embryonated cells (cefs) infected with field isolates of fowl poxvirus (fpv). by the polymerase chain reaction (pcr), five out of the six field isolates, but two out of the seven vaccine strains of fpv, were found to have had a 291 bp repeat sequence of rev-ltr integrated in their genomic dna. an immunofluorescence (if) method was employed using a monoclonal antibody (mab) known to specify strain ... | 2003 | 12757926 |
| infection with chicken anaemia virus impairs the generation of pathogen-specific cytotoxic t lymphocytes. | infection with chicken anaemia virus (cav), a circovirus, can result in immunosuppression and subsequent increased susceptibility to secondary infections. this is the first report of impairment of pathogen-specific cytotoxic t lymphocytes (ctl) after natural and experimental infection of chickens with cav and marek's disease virus (mdv) or reticuloendotheliosis virus (rev). mdv- and rev-specific ctl were generated at 7 days post infection by 9-30-day-old-chickens that were positive for maternal ... | 2003 | 12757624 |
| reticuloendotheliosis virus sequences within the genomes of field strains of fowlpox virus display variability. | nine field strains of fowlpox virus (fpv) isolated during a 24-year span from geographically diverse outbreaks of fowlpox in the united states were screened for the presence of reticuloendotheliosis virus (rev) sequences in their genomes by pcr. each isolate appeared to be heterogeneous in that either a nearly intact provirus or just a 248- or 508-nucleotide fusion of portions of the integrated rev 5' and 3' long terminal repeats (ltrs) was exclusively present at the same genomic site. in contra ... | 2003 | 12719579 |
| reticuloendotheliosis viruses and derived vectors for human gene therapy. | the reticuloendotheliosis viruses (rev) spleen necrosis virus (snv) and reticuloendotheliosis virus strain-a (rev-a) are amphotropic retroviruses which infect a large variety of cells of avian and some mammalian species. they normally do not infect primate or rodent cells. however, they efficiently infect and integrate their genome into that of human cells when they are pseudotyped with the envelope protein of other mammalian retroviruses or the g protein of vesicular stomatitis virus (vsv) or r ... | 2003 | 12700113 |
| infectious disease survey of lesser prairie chickens in north texas. | lesser prairie chicken (tympanuchus pallidicinctus) abundance, like that of most grassland birds, has declined rangewide for decades. although habitat loss and degradation are likely ultimate causes for this decline, infectious agents, particularly microparasites, could be proximate contributors. no surveys of pathogenic bacteria or viruses have been published for this species. we surveyed 24 free-living lesser prairie chickens from hemphill county, texas (usa), for evidence of exposure to salmo ... | 2002 | 12528454 |
| infectious disease survey of rio grande wild turkeys in the edwards plateau of texas. | state wildlife agencies have translocated thousands of wild turkeys (meleagris gallopavo) since the 1930s to reestablish this species. because of threats to the domestic poultry industry and wild birds, screening for selected infectious agents has become routine since the early 1980s. one of the principal sources for rio grande wild turkeys (m. gallopavo intermedia) for translocation purposes was the edwards plateau of texas (usa). unfortunately, turkey abundance has declined in the southern edw ... | 2002 | 12528453 |
| isolation and characterization of chicken interleukin-17 cdna. | interleukin-17 (il-17) is a proinflammatory cytokine produced by activated t cells. a 917-bp cdna encoding the il-17 gene was isolated from our est cdna library prepared from intestinal intraepithelial lymphocytes (iels) of eimeria-infected chickens. it contained a 507-bp open reading frame (orf) predicted to encode a protein of 169 amino acids (aa) with a molecular mass of 18.9 kda, a 27-residue nh(2)-terminal signal peptide, a single potential n-linked glycosylation site, and 6 cysteine residu ... | 2002 | 12513911 |
| differential regulation of the inhibitor of apoptosis ch-iap1 by v-rel and the proto-oncogene c-rel. | the v-rel oncogene encoded by reticuloendotheliosis virus is the acutely transforming member of the rel/nf-kappab family of transcription factors. v-rel is a truncated and mutated form of c-rel and transforms cells by inducing the aberrant expression of genes regulated by rel/nf-kappab proteins. the expression of ch-iap1, a member of the inhibitor-of-apoptosis family, is highly elevated in cells expressing v-rel and contributes to the immortalization of cells transformed by this oncoprotein. in ... | 2002 | 12414938 |
| characterization of t-cell lymphomas associated with an outbreak of reticuloendotheliosis in turkeys. | increased mortality and decreased egg production associated with disseminated lymphoma were observed in a turkey breeding flock for more than 20 weeks. a few unrelated meat turkey flocks, from the same integrator, experienced increased condemnation due to neoplasia in a few organs. lymphoma was characterized by a uniform population of large lymphocytes with large vesicular nuclei containing one or two nucleoli and with little, faintly staining, basophilic cytoplasm. neoplastic cells replaced nor ... | 2002 | 12396336 |
| reticuloendotheliosis in hungarian partridge. | a large commercial flock of hungarian partridge (perdix perdix) experienced elevated mortality associated with a wasting disease in may 1998. postmortem examination of females consistently revealed a distended crop and abnormal gray-white tissue infiltrating the wall of the crop and thoracic esophagus. neoplasia in male partridge was observed in the liver. microscopic examination of the crop and thoracic esophagus revealed transmural masses of immature lymphocytes with frequent mitotic figures. ... | 2002 | 12038145 |
| mutational analysis of the v-rel dimerization interface reveals a critical role for v-rel homodimers in transformation. | the v-rel oncogene encoded by reticuloendotheliosis virus strain t is the acutely transforming member of the rel/nf-kappab family of transcription factors. in v-rel-transformed cells, v-rel exists as homodimers or heterodimers with the endogenous rel/nf-kappab proteins c-rel, nf-kappab1, nf-kappab2, and rela. to examine the contribution of these complexes to v-rel-mediated transformation, mutations were introduced into the dimerization interface of v-rel to generate v-rel mutants with selective ... | 2002 | 11967310 |
| serological investigations on reticuloendotheliosis in turkey flocks. | four meat turkey and one turkey breeding flocks were surveyed for antibodies against reticuloendotheliosis virus (rev) at different intervals using commercial enzyme-linked immunosorbent assays. in addition, serum samples collected from 18 flocks at different ages were also tested for antibodies against rev. no antibodies were detected in any of the four meat turkey flocks that were surveyed. in the breeder flock, 20%) of tested samples from 1-day-old poults were positive. between the fourth and ... | 2001 | 11666037 |
| reticuloendotheliosis virus integration in the fowl poxvirus genome: not a recent event. | integration of reticuloendotheliosis virus (rev) into the genome of fowl poxvirus (fpv) has been reported recently. with a view to determine whether this event had occurred in the past, we screened by polymerase chain reaction (pcr) for the presence of rev provirus in the dnas of nine avian poxviruses, some of which had been lyophilized 50 yr ago. for rev, 5' long terminal repeat (ltr) and rev envelope sequences were amplified, whereas for fpv, the major envelope antigen gene and the region flan ... | 2001 | 11569741 |
| efficient gene transfer in mouse neural precursors with a bicistronic retroviral vector. | gene transfer into neural precursors is a powerful approach to study the function of specific gene products during nervous system development. here we describe a retrovirus-based methodology to transduce foreign genes into mouse neural precursors. we used a high-titer bicistronic retroviral vector that encodes a marker gene, placental alkaline phosphatase (plap), and a selection gene, neomycin phosphotransferase ii (neor), under the translational control of two retroviral internal ribosome entry ... | 2001 | 11494355 |
| growth hormone interacts with the marek's disease virus sorf2 protein and is associated with disease resistance in chicken. | marek's disease (md) is a lymphoproliferative disease of chickens induced by a herpesvirus, the md virus (mdv). because md is a significant economic problem to the poultry industry, there is great interest in enhancing genetic resistance, which is controlled by multiple genes. the influence of the mhc has been clearly demonstrated, and several relevant quantitative trait loci have been mapped; however, no single gene influencing md resistance has been identified. transcription of sorf2 is pertur ... | 2001 | 11470922 |
| in vivo events of retroviral long terminal repeat integration into marek's disease virus in commercial poultry: detection of chimeric molecules as a marker. | the present study demonstrated, for the first time, that not only in vitro, but also in vivo, coinfections with marek's disease virus (mdv) and each of the three avian retroviruses (reticuloendotheliosis virus [rev], avian lymphoid leukosis virus [alv], and alv-j) lead to retroviral long terminal repeat (ltr) integration into mdv. a total of 306 chicken and 59 turkey commercial flocks, submitted for differential avian oncogenic virus diagnosis, served to evaluate the flock mixed virus infection ... | 2001 | 11332471 |
| reticuloendotheliosis virus (rev) long terminal repeats incorporated in the genomes of commercial fowl poxvirus vaccines and pigeon poxviruses without indication of the presence of infectious rev. | because of reticuloendotheliosis virus (rev) contamination in commercial poultry vaccines, polymerase chain reaction (pcr) assays have been described to increase the sensitivity of biological assays used to detect rev in vaccines. the pcr assay designed to amplify the long terminal repeat (ltr) region of rev identified rev ltrs in many of the commercial fowl poxvirus (fpv) vaccines evaluated. these commercial vaccines were not thought to be contaminated with replicating rev because of the lack o ... | 2000 | 11195637 |
| rous sarcoma virus translation revisited: characterization of an internal ribosome entry segment in the 5' leader of the genomic rna. | the 5' leader of rous sarcoma virus (rsv) genomic rna and of retroviruses in general is long and contains stable secondary structures that are critical in the early and late steps of virus replication such as rna dimerization and packaging and in the process of reverse transcription. the initiation of rsv gag translation has been reported to be 5' cap dependent and controlled by three short open reading frames located in the 380-nucleotide leader upstream of the gag start codon. translation of r ... | 2000 | 11090156 |
| defence mechanisms against viral infection in poultry: a review. | defence against viral infections in poultry consists of innate and adaptive mechanisms. the innate defence is mainly formed by natural killer cells, granulocytes, and macrophages and their secreted products, such as nitric oxide and various cytokines. the innate defence is of crucial importance early in viral infections. natural killer cell activity can be routinely determined in chickens of 4 weeks and older using the rp9 tumour cell line. in vitro assays to determine the phagocytosis and killi ... | 2000 | 11087131 |
| tricistronic and tetracistronic retroviral vectors for gene transfer. | we have combined the picornavirus foot-and-mouth disease virus (fmdv) 2a sequence and the internal ribosome entry sites (ireses) from encephalomyocarditis virus (ecmv) and avian reticuloendotheliosis virus type a (rev-a) to construct tricistronic and tetracistronic vectors. all the polycistronic constructs show high titers and expression of the genes inserted. clones have been obtained in which cells simultaneously express the three or four genes carried by the polycistronic vectors. | 2000 | 10986564 |
| inhibition of eimeria tenella replication after recombinant ifn-gamma activation in chicken macrophages, fibroblasts and epithelial cells. | we have previously shown that activation of primary cultures of chicken bone-marrow macrophages and embryo fibroblasts with supernatants of concanavaline a-stimulated or reticuloendotheliosis virus (rev)-transformed chicken spleen cells as source of ifn-gamma significantly decreases eimeria tenella growth in vitro. in the present study, we used various chicken cell lines, hd11 macrophages and du24 fibroblasts, both virally transformed, chcc-ou2 fibroblasts and lmh hepatic epithelial cells, both ... | 2000 | 10936544 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| avian reticuloendotheliosis virus strain a and spleen necrosis virus do not infect human cells. | spleen necrosis virus (snv) and reticuloendotheliosis virus strain a (rev-a) belong to the family of reticuloendotheliosis viruses and are 90% sequence related. snv-derived retroviral vectors produced by the rev-a-based d17.2g packaging cell line were shown to infect human cells (h.-m. koo, a. m. c. brown, y. ron, and j. p. dougherty, j. virol. 65:4769-4776, 1991), while similar vectors produced by another snv-based packaging cell line, dsh134g, are not infectious in human cells (reviewed by r. ... | 2000 | 10590142 |
| the nucleocapsid domain is responsible for the ability of spleen necrosis virus (snv) gag polyprotein to package both snv and murine leukemia virus rna. | murine leukemia virus (mlv)-based vector rna can be packaged and propagated by the proteins of spleen necrosis virus (snv). we recently demonstrated that mlv proteins cannot support the replication of an snv-based vector; rna analysis revealed that mlv proteins cannot efficiently package snv-based vector rna. the domain in gag responsible for the specificity of rna packaging was identified using chimeric gag-pol expression constructs. a competitive packaging system was established by generating ... | 1999 | 10516024 |
| identification of an internal ribosome entry segment in the 5' region of the mouse vl30 retrotransposon and its use in the development of retroviral vectors. | mouse virus-like 30s rnas (vl30m) constitute a family of retrotransposons, present at 100 to 200 copies, dispersed in the mouse genome. they display little sequence homology to moloney murine leukemia virus (momlv), do not encode virus-like proteins, and have not been implicated in retroviral carcinogenesis. however, vl30 rnas are efficiently packaged into mlv particles that are propagated in cell culture. in this study, we addressed whether the 5' region of vl30m could replace the 5' leader of ... | 1999 | 10482590 |
| mechanisms of the eimeria tenella growth inhibitory activity induced by concanavalin a and reticuloendotheliosis virus supernatants with interferon gamma activity in chicken macrophages and fibroblasts. | pretreatment of chicken bone marrow macrophages and embryo fibroblasts with supernatants containing chicken interferon gamma (ifn-gamma) for 24 hr prior to inoculation inhibited intracellular eimeria tenella replication, measured by [3h] uracil incorporation. the supernatants (sns) were obtained from culture of lymphoblastoid cells transformed by a reticuloendotheliosis virus (rev) and chicken splenocytes stimulated with concanavalin a (con a). the mechanisms of the e. tenella growth inhibitory ... | 1999 | 10216761 |
| a sodium-dependent neutral-amino-acid transporter mediates infections of feline and baboon endogenous retroviruses and simian type d retroviruses. | the type d simian retroviruses cause immunosuppression in macaques and have been reported as a presumptive opportunistic infection in a patient with aids. previous evidence based on viral interference has strongly suggested that the type d simian viruses share a common but unknown cell surface receptor with three type c viruses: feline endogenous virus (rd114), baboon endogenous virus, and avian reticuloendotheliosis virus. furthermore, the receptor gene for these viruses has been mapped to huma ... | 1999 | 10196349 |
| pulmonary sarcomas in a young chicken. | both lungs of a 5-wk-old broiler chicken contained miliary, round, white tumors. microscopically, these masses were composed of compactly arranged cells with round to oval nuclei and indistinct cytoplasmic borders. immunohistochemically, tumor cells were positive for vimentin but negative for cytokeratin, s-100 protein, neuron-specific enolase, smooth muscle actin, and muscle-specific actin. ultrastructurally, tumor cells were separated by collagen bands and some contained collagen fibrils. thes ... | 1998 | 9876857 |
| reticuloendotheliosis in captive greater and attwater's prairie chickens. | reticuloendotheliosis in captive greater (tympanuchus cupido pinnatus) and attwater's (t. cupido attwateri) prairie chickens is reported for the first time. between september 1993 and august 1994, two adult female wild-caught greater prairie chickens housed at texas a&m university (college station, texas, usa) were observed with multiple subcutaneous nodules. both birds were euthanatized. complete necropsy examinations revealed lesions limited to the skin of each bird. histopathologic examinatio ... | 1998 | 9813849 |
| resistance to salmonella enteritidis organ invasion in day-old turkeys and chickens by transformed t-cell line-produced lymphokines. | we previously reported an increased resistance to salmonella enteritidis (se) organ invasion in chicks and turkey poults injected prophylactically with se-immune lymphokines (ilk). in the present study, concanavalin a (con-a)-activated splenic t cells isolated from se-hyperimmunized hens were transformed in vitro with reticuloendotheliosis virus strain t (rev-t) (chicken syncitial virus). these transformed t cells were then maintained as a long-term (> 1 yr) cell line for the harvest of immune l ... | 1998 | 9777155 |
| the secondary structure of the r region of a murine leukemia virus is important for stimulation of long terminal repeat-driven gene expression. | in addition to their role in reverse transcription, the r-region sequences of some retroviruses affect viral transcription. the first 28 nucleotides of the r region within the long terminal repeat (ltr) of the murine type c retrovirus sl3 were predicted to form a stem-loop structure. we tested whether this structure affected the transcriptional activity of the viral ltr. mutations that altered either side of the stem and thus disrupted base pairing were generated. these decreased the level of ex ... | 1998 | 9733816 |
| retrovirus-induced disease in poultry. | three species of avian retrovirus cause disease in poultry: the avian leukosis/sarcoma virus (alsv), reticuloendotheliosis virus (rev), and lymphoproliferative disease virus (lpdv) of turkeys. the alsv can be classified as slowly transforming viruses, which lack a viral oncogene, and acutely transforming viruses, which possess a viral oncogene. slowly transforming viruses induce late onset leukoses of the b cell lymphoid, erythroid, and myeloid cell lineages, and other tumors, by viral promoter ... | 1998 | 9706091 |
| orbital lymphosarcoma associated with reticuloendotheliosis virus in a peafowl. | lymphosarcoma associated with infection by avian reticuloendotheliosis virus was diagnosed in an indian peafowl with exophthalmia and exposure keratitis. exenteration of the orbit was complicated by a profound oculocardiac reflex and extensive hemorrhage during surgery. orbital bleeding was controlled by direct pressure, electrocautery, topical administration of bovine thrombin, and application of sterile gelatin sponges and oxidized regenerated cellulose. a blood transfusion was also performed. ... | 1998 | 9702227 |
| cytotoxic t lymphocyte response in chickens immunized with a recombinant fowlpox virus expressing marek's disease herpesvirus glycoprotein b. | previously, we demonstrated that cytotoxic t lymphocytes (ctls) from mhc: b19b19 and mhc: b21b21 chickens inoculated with a non-oncogenic marek's disease virus (mdv) vaccine strain, sb-1/12 can lyse syngeneic reticuloendotheliosis virus (rev)-transformed cell lines expressing mdv pp38 or gb genes. in this study, we report the characterization of mdv gb-specific ctls in chickens immunized with recombinant fowlpox virus expressing mdv gb gene (rfpv-gb). spleen cells from rfpv-gb inoculated chicken ... | 1998 | 9618870 |
| isolation of serotype 2 marek's disease virus from a cell line of avian lymphoid leukosis. | to determine a serotype of marek's disease virus (mdv) persistently infected in a lymphoid leukosis (ll)-cell line, lscc-bk3, clone a (bk3a), and to examine the pathogenicity of the virus, an attempt was made to isolate mdv from culture fluid of the ll-cell line, using chick embryo fibroblast cultures resistant to infection with subgroup a avian leukosis virus (alv) to eliminate subgroup a alv. the mdv isolate, serologically identified as serotype 2 mdv and designated as the 2h strain, was free ... | 1998 | 9524935 |
| rapid induction of lymphoid leukosis and ascites by avian leukosis virus from a lymphoid leukosis cell line. | to examine whether a lymphoid leukosis (ll) cell line releases an ll-specific avian leukosis virus (alv) or not, two viral materials, culture fluid and a concentrated viral material from an ll-cell line, were inoculated into a total of 74 day-old chicks of line 15i in 5 experiments. spectrum of diseases induced, their incidence and incubation periods to onset were examined. fifteen chicks were inoculated with the culture fluid and 9 (60%) developed ascites [59-119 days post inoculation (dpi); ge ... | 1998 | 9492364 |
| characterization of an internal ribosomal entry segment within the 5' leader of avian reticuloendotheliosis virus type a rna and development of novel mlv-rev-based retroviral vectors. | the murine leukemia virus (mlv)-related type c viruses constitute a major class of retroviruses that includes numerous endogenous and exogenous mammalian viruses and the related avian spleen necrosis virus (snv). the mlv-related viruses possess a long and multifunctional 5' untranslated leader involved in key steps of the viral life cycle--splicing, translation, rna dimerization, encapsidation, and reverse transcription. recent studies have shown that the 5' leader of friend murine leukemia viru ... | 1997 | 9382952 |
| comparative evaluation of in vitro and in vivo assays for the detection of reticuloendotheliosis virus as a contaminant in a live virus vaccine of poultry. | indirect immunofluorescence (ifa), polymerase chain reaction (pcr), and enzyme-linked immunosorbent assay (elisa) were used for detection of reticuloendotheliosis virus (rev) as a contaminant in a live virus fowl pox (fp) vaccine of poultry. a fp vaccine known to be contaminated with rev was tested by in vitro and in vivo assays in chicken embryo fibroblasts (cefs) and day-old specific-pathogen-free (spf) chicks, respectively. using in vitro assays, ifa and pcr were more sensitive than elisa in ... | 1997 | 9356718 |
| field and vaccine strains of fowlpox virus carry integrated sequences from the avian retrovirus, reticuloendotheliosis virus. | for baculoviruses and herpesviruses, integration of transposons or retroviruses into the virus genome has been documented. we report here that field and vaccine strains of fowlpox virus (fpv) carry integrated sequences from the avian retrovirus, reticuloendotheliosis virus (rev). using pcr and hybridization analysis we observed that vaccine and field strains of fpv carry rev sequences integrated into a previously uncharacterized region of the right 1/3 of the fpv genome. long-range pcr, hybridiz ... | 1997 | 9281517 |
| retroviral techniques for studying organogenesis with a focus on heart development. | the study of development has been revolutionized by the application of molecular techniques, which make it possible to identify factors involved in the developmental process. however, in order to correctly assess the contribution of these growth factors, transcription factors, receptors or signaling molecules, it is necessary to study them in the animal as a whole; it is not enough to conclude that they must be important based on their expression patterns. | 1997 | 9278229 |
| avian tumor viruses: persistent and evolving pathogens. | most neoplasias of lymphoid and other hematopoietic cells in commercial poultry are caused by viruses which belong to one of four distinct groups. marek's disease virus (mdv) is an oncogenic herpesvirus. avian leukosis virus (alv), reticuloendotheliosis virus (rev) and lymphoproliferative disease virus (lpdv) are oncogenic retroviruses. each group is distinguished by nucleic acid type, molecular structure, antigenicity, epidemiology, host range and other characteristics. however, most of these v ... | 1997 | 9276987 |
| viral diseases of the immune system and strategies to control infectious bursal disease by vaccination. | viral infections which are immunosuppressive can affect the economics of poultry production, often as a result of the chicken's increased susceptibility to secondary infections and sub-optimal response to vaccinations. the mechanism of this immunosuppression has been studied in detail for certain chicken viruses. the replicating virus can have both direct and indirect effects on the cells of the immune system. the special role of the bursa of fabricius, as a lympho-epithelial organ, will be ment ... | 1997 | 9276986 |
| c-jun involvement in vitamin e succinate induced apoptosis of reticuloendotheliosis virus transformed avian lymphoid cells. | previous studies have shown that treatment of avian reticuloendotheliosis virus-transformed recc-utc4-1 (c4-1) lymphoblastoid cells with 10 microg/ml (18.8 microm) of rrr-alpha-tocopheryl succinate (vitamin e succinate, ves) for 3 days induced approximately 50% of the cells to undergo apoptosis. elevated and prolonged expression of c-jun mrna and protein was temporally correlated with ves-induced cell death. data presented in this paper show that the elevated and prolonged expression of c-jun me ... | 1997 | 9244357 |
| v-rel activates the proto-oncogene c-jun promoter: a correlation with its transforming activity. | v-rel is a transforming protein of the reticuloendotheliosis virus, and is a transcription factor regulating various cellular genes. we found that v-rel activates the promoter of the proto-oncogene c-jun in a transient transfection assay system. moreover, the expression of endogenous c-jun was augmented in cells expressing exogenous v-rel, but not c-rel. the transcriptional activities of v-rel to the tested promoters containing the kb-site are lower than that of c-rel, but that to the c-jun prom ... | 1997 | 9209405 |
| differences in kappab dna-binding properties of v-rel and c-rel are the result of oncogenic mutations in three distinct functional regions of the rel protein. | the oncogene v-rel of reticuloendotheliosis virus, strain t, is derived from an avian c-rel proto-oncogene. c-rel encodes a member of the rel/nf-kappab family of transcription factors. the highly oncogenic v-rel differs from c-rel which has low transforming potential by the acquisition of numerous mutations. in this manuscript, we demonstrate that the oncogenic mutations in v-rel directly alter the ability of this protein to bind to dna. electrophoretic mobility shift analysis with rel proteins ... | 1997 | 9205096 |
| retroviral insertional mutagenesis of a herpesvirus: a marek's disease virus mutant attenuated for oncogenicity but not for immunosuppression or in vivo replication. | our earlier studies have shown that retrovirus insertion into herpesvirus is an efficient process that engenders recombinant herpesviruses with altered biological properties. the rm1 clone is derived from the jm strain of marek's disease virus (mdv) through retrovirus insertional mutagenesis and contains sequences of reticuloendotheliosis virus inserted at the junction of the internal repeat and unique short regions of the genome. in previous studies, the rm1 clone appeared attenuated for oncoge ... | 1997 | 9201407 |
| characterization of marek's disease herpesvirus-specific cytotoxic t lymphocytes in chickens inoculated with a non-oncogenic vaccine strain of mdv. | previously we have reported that reticuloendotheliosis virus (rev)-transformed cell lines expressing marek's disease virus (mdv) genes pp38, meq or gb were lysed by syngeneic mdv-specific splenocytes from major histocompatibility complex (mhc):b9b19 and mhc:b1b21 chickens. in contrast, rev-transformed cell lines expressing the mdv gene icp4 were only lysed by syngeneic mdv-specific splenocytes from mhc:b21b21 chickens. in this study we report that this syngeneic cell-mediated immune response is ... | 1997 | 9176112 |
| the antiretrovirus drug 3'-azido-3'-deoxythymidine increases the retrovirus mutation rate. | it was previously observed that the nucleoside analog 5-azacytidine increased the spleen necrosis virus (snv) mutation rate 13-fold in one cycle of retrovirus replication (v. k. pathak and h. m. temin, j. virol. 66:3093-3100, 1992). based on this observation, we hypothesized that nucleoside analogs used as antiviral drugs may also increase retrovirus mutation rates. we sought to determine if 3'-azido-3'-deoxythymidine (azt), the primary treatment for human immunodeficiency virus type 1 (hiv-1) i ... | 1997 | 9151812 |
| avian retroviruses. | avian leukosis virus (alv) and reticuloendotheliosis virus (rev) are the most common naturally occurring avian retroviruses associated with neoplastic disease conditions in domesticated poultry. avian leukosis virus infects primarily chickens, whereas rev infects chickens, turkeys, and other avian species. in addition to causing tumors, both alv and rev can reduce productivity and induce immunosuppression and other production problems in affected flocks. | 1997 | 9071747 |