Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| characterization of particles formed by the precursor protein vpx of infectious bursal disease virus in insect hi-5 cells: implication on its proteolytic processing. | the precursor (vpx) of host immunogen vp2 protein for infectious bursal disease virus (ibdv) was expressed in insect sf9 and hi-5 cells, and the types of particles generated as well as the immunogenicity induced by these particles were examined. recombinant vpxh (rvpxh) protein, expressed in hi-5 cells at an expression level 4x higher than in sf9 cells, was efficiently processed by proteases to yield vp2-like proteins with corresponding molecular weight, a phenomenon not observed previously. at ... | 2004 | 15381356 |
| molecular characterization of an infectious bursal disease virus isolate from iran. | the segment a of an infectious bursal disease virus (ibdv) isolate from iran was amplified by reverse transcription-polymerase chain reaction (rt-pcr), sequenced and compared with published sequences of 26 ibdv isolates from other parts of the world. the iranian isolate showed 8 unique amino acid differences. in addition, 9 common amino acid differences, namely 3 in vp2, (222 ala, 256 lie and 294 lie), 3 in vp4 (685 asn/ser, 715 ser and 751 asp), 2 in vp3 (990 val and 1005 ala), and 1 in vp5 (49 ... | 2004 | 15462282 |
| enhancement of the immunogenicity of dna vaccine against infectious bursal disease virus by co-delivery with plasmid encoding chicken interleukin 2. | the immunoregulatory activity of a nonmammalian interleukin 2 (il-2), chicken il-2 (chil-2), was investigated using a dna vaccine against infectious bursal disease virus (ibdv) as a model. coadministration of a plasmid encoding the vp2 gene of ibdv (pci-vp2) and a plasmid encoding chicken il-2 gene (pci-chil-2) enhances bursal protection against both the homologous ibdv strain zj2000 and the heterologous strain bc6/85 compared to administration of pci-vp2 alone. vaccination with pci-vp2 alone in ... | 2004 | 15476877 |
| vp1, the rna-dependent rna polymerase and genome-linked protein of infectious bursal disease virus, interacts with the carboxy-terminal domain of translational eukaryotic initiation factor 4aii. | infectious bursal disease virus (ibdv), a member of the family birnaviridae, is a non-enveloped, double-stranded rna virus. viral protein 1 (vp1), the putative rna-dependent rna polymerase, occurs in virions both as a free polypeptide and as a genome-linked protein, called vpg. to gain more insight in its function, we initiated a yeast two-hybrid screen. with this approach we identified the carboxy-terminal domain of eukaryotic translation initiation factor 4aii (eif4aii) as an interactor for vp ... | 2004 | 15503210 |
| rt-pcr amplification and bmri restriction digestion for the rapid detection of exotic strains of infectious bursal disease virus. | 2003 | 15080431 | |
| differentiation of classical and very virulent strains/isolates of infectious bursal disease virus by reverse transcription-polymerase chain reaction. | reverse transcription-polymerase chain reaction (rt-pcr) is a rapid method for identification and differentiation of viruses. it was used to differentiate very virulent from classical (field/vaccine) strains/isolates of infectious bursal disease virus (ibdv). rt-pcr products of 552 bp were generated by amplification of variable region of vp2 gene in three field classical isolates, two vaccine strains and two very virulent isolates of ibdv. the pcr products were digested with saci, hhai, sspi and ... | 2003 | 15068382 |
| efficacy of a recombinant vaccine hvt-vp2 against gumboro disease in the presence of maternal antibodies. | 2003 | 14965139 | |
| dna vaccination with plasmids containing various fragments of large segment genome of infectious bursal disease virus. | the present study was undertaken to determine the effectiveness in including vp2 gene of the large segment genome of infectious bursal disease virus (ibdv) in the dna vaccine for protection of chickens against infectious bursal disease (ibd). different fragments of the large segment gene of ibdv standard challenge (stc) strain were successfully amplified by reverse transcription-polymerase chain reaction (rt-pcr) followed by cloning into a eukaryotic expression plasmid vector (pcr3.1) as dna vac ... | 2003 | 12531650 |
| identification and molecular characterization of the rna polymerase-binding motif of infectious bursal disease virus inner capsid protein vp3. | infectious bursal disease virus (ibdv), a member of the birnaviridae family, is the causative agent of one of the most important infectious poultry diseases. major aspects of the molecular biology of ibdv, such as assembly and replication, are as yet poorly understood. we have previously shown that encapsidation of the putative virus-encoded rna-dependent rna polymerase vp1 is mediated by its interaction with the inner capsid protein vp3. here, we report the characterization of the vp1-vp3 inter ... | 2003 | 12551984 |
| in ovo delivery of dna to the avian embryo. | we have developed a simple method of transfecting avian embryos in ovo with various plasmid vectors that results in protein expression in the embryo. using the chloramphenicol acetyl transferease (cat) reporter gene, we were able to show that transfecting avian embryos with a plasmid/neutral lipid/dimethylsulfoxide (dmso) mixture delivered to the air cell, is better than transfecting naked dna or cationic lipid encapsulated dna, using dmso (p < 0.05). this method resulted in cat expression in se ... | 2003 | 12559809 |
| differentiation of infectious bursal disease viruses by restriction enzyme analysis of rt-pcr amplified vp1 gene sequence. | in order to differentiate infectious bursal disease virus (ibdv) isolates/strains, a quick method of rt-pcr followed by restriction enzyme analysis of vp1 gene sequence is being reported for the first time. a 480 bp fragment, comprising one of the rna dependent rna polymerase motifs of vp1 gene sequence of an indian classical virus, an attenuated vaccine strain, georgia and two indian field isolates, genetically similar to reported very virulent strains of ibdv, was amplified by rt-pcr. restrict ... | 2003 | 12602686 |
| generation of chicken single chain antibody variable fragments (scfv) that differentiate and neutralize infectious bursal disease virus (ibdv). | phage-displayed recombinant antibody libraries derived from splenic mrna of chickens immunized with an australian strain of infectious bursal disease virus (ibdv) were constructed as single chain variable fragments (scfv) by either overlap extension polymerase chain reaction (pcr) or sequential ligation of the individual heavy (v(h)) and light (v(l)) chain variable gene segments. sequential cloning of the individual v(h) and v(l) genes into a newly constructed pcantab-link vector containing the ... | 2003 | 12607101 |
| characterization of the rna-binding activity of vp3, a major structural protein of infectious bursal disease virus. | infectious bursal disease virus (ibdv) is the agent of an immune-depressive disease affecting the poultry industry worldwide. infection of ibdv leads to expression of five mature virus-encoded proteins. proteolytic processing of the virus-encoded polyprotein generates vp3 which coats the inner surface of the ibdv capsid. in this report, we describe the characterization of the rna-binding activity of vp3. for these studies, the vp3 coding region was fused to a histidine tag and expressed in insec ... | 2003 | 12664296 |
| sequence and analysis of genomic segment a and b of very virulent infectious bursal disease virus isolated from china. | a very virulent infectious bursal disease virus (vvibdv) field strain, named sh95, was identified and characterized from flocks with vaccination failure in shanghai. the use of random primer and a reverse transcriptase lacking rnase-h activity produced full-length cdna copies of the viral genomic a and b segments of sh95. the 3259 base pairs (bp) of segment a and 2827 bp of segment b were amplified by long and accurate pcr in a single step, then successfully cloned and sequenced. there were five ... | 2003 | 12667193 |
| identification of crucial residues of conformational epitopes on vp2 protein of infectious bursal disease virus by phage display. | a new method for identifying epitopes in viral proteins expressed by filamentous phage has been developed. filamentous phage fuse 1 containing the variable region of the vp2 gene of infectious bursal disease virus (ibdv) strain 002-73 was constructed. neutralizing monoclonal antibodies 17-82 and 33-10 raised against vp2 protein were used to bind phage containing the original variable region of vp2. the phage bound to monoclonal antibodies, were removed by protein g sepharose and the unbound phag ... | 2003 | 12668271 |
| [rapid construction of infectious clones of infectious bursal disease virus]. | a rapid procedure was established for rescuing infectious bursal disease virus (ibdv), an important pathogen in poultry. a full-length cdna clone of the segment b of a cef-adapted ibdv strain hz2 was constructed by long rt-pcr, and the 2827 bp nucleotide sequence, including the 5 - and 3 -noncoding regions (ncr), was established. then the cdna clone of segment b was engineered to make it contain three silent nucleotide changes, creating a new ecorv site that was different from the parent virus s ... | 2003 | 12673387 |
| cloning and nucleotide analysis of segment a gene of infectious bursal disease virus detected in korea. | a strain of infectious bursal disease virus (ibdv) was detected from bursal tissues of chicks which suffered from infectious bursal disease (ibd) in chinju, korea and provisionally named as chinju strain. a full-length cdna clone for segment a gene of the virus was constructed, and complete nucleotide sequence of the gene including noncoding region was determined and analyzed by comparison with that of other ibdv strains. the segment a gene of chinju strain consisted of 3,269 nucleotides includi ... | 2003 | 12680697 |
| structure-dependent efficacy of infectious bursal disease virus (ibdv) recombinant vaccines. | the immunogenicity and protective capability of several baculovirus-expressed infectious bursal disease virus (ibdv)-derived assemblies as vp2 capsids, vpx tubules and polyprotein (pp)-derived mixed structures, were tested. four-week-old chickens were immunised subcutaneously with one dose of each particulate antigen. vp2 icosahedral capsids induced the highest neutralising response, followed by pp-derived structures and then vpx tubules. all vaccinated animals were protected when challenged wit ... | 2003 | 12706682 |
| differentiation of infectious bursal disease viruses isolated in croatia. | infectious bursal disease viruses (ibdvs) in 26 ibdv-positive bursa samples collected in croatia during the period 1996-2000 and in two commercially available vaccines were differentiated by the presence or absence of the cfoi, saci, sspi, stui, and taqi restriction sites in the 422-bp fragment of segment a of the vp2 gene (nt 732-1153). the fragments from 14 (54%) field isolates were taqi+ stui+ sspi+ and saci- cfoi-, indicating their very virulent (vv) character. the presence of cfoi restricti ... | 2003 | 12713159 |
| comparative immunopathogenesis of mild, intermediate, and virulent strains of classic infectious bursal disease virus. | differences in the immunopathogenesis of several strains of infectious bursal disease virus (ibdv) were compared. the strains included a virulent virus (ibdv-im) and three vaccine viruses that included an intermediate vaccine virus (ibdv-b2) and two mild vaccine viruses (ibdv-lukert and ibdv-bvm). the most significant differences were found in the systemic effects of these strains. in comparison with other strains, ibdv-im antigen was detectable for up to 8 days postinfection (pi) in lymphoid ti ... | 2003 | 12713160 |
| molecular characterization of infectious bursal disease virus from commercial poultry in the united states and latin america. | from june 1999 to september 2001, 216 bursal samples from broiler farms in the united states and from countries of latin america were submitted to the poultry diagnostic and research center at the university of georgia for the purpose of genotyping field infectious bursal disease viruses (ibdvs). the reverse transcriptase-polymerase chain reaction (rt-pcr) was used to amplify a 248-bp product, encompassing the hypervariable region of vp2 gene. the genotyping was conducted by restriction fragment ... | 2003 | 12713162 |
| sequence analysis of malaysian infectious bursal disease virus isolate and the use of reverse transcriptase nested polymerase chain reaction enzyme-linked immunosorbent assay for the detection of vp2 hypervariable region. | the vp2 hypervariable region of p97/302 local infectious bursal disease virus (ibdv) isolate was amplified by the reverse transcriptase (rt) nested polymerase chain reaction (pcr) and cloned. this region of p97/302 local isolate was sequenced and compared with eight other reported ibdv sequences. the result showed that p97/302 ibdv was most identical to the reported very virulent ibdv strains because it has amino acid substitutions at positions 222, 256, 294, and 299, which encode alanine, isole ... | 2003 | 12713171 |
| very virulent infectious bursal disease virus in southeastern europe. | clinical outbreaks of severe acute infectious burial disease (ibd) were recorded since the mid- and late 1990s in several countries in the southeastern part of europe. epidemiologic data showed that both infectious bursal disease virus (ibdv)-vaccinated and ibdv-nonvaccinated chickens were affected with acute ibd and mortality up to 50% independent of the ibdv vaccination status of the appropriate parent flocks. for investigation of the causative agent of acute ibd, the variable region of vp2 wa ... | 2003 | 12713176 |
| the immunologists' debt to the chicken. | the immune system of the chicken is an invaluable model for studying basic immunology and has made seminal contributions to fundamental immunological principles. graft versus host responses and the key role of lymphocytes in adaptive immunity were first described in work with chicken embryos and chickens. 2. most notably, the bursa of fabricius provided the first substantive evidence that there are two major lineages of lymphocytes. bursa-derived lymphocytes, or b cells, make antibodies while th ... | 2003 | 12737220 |
| the oligomerization domain of vp3, the scaffolding protein of infectious bursal disease virus, plays a critical role in capsid assembly. | infectious bursal disease virus (ibdv) capsids are formed by a single protein layer containing three polypeptides, pvp2, vp2, and vp3. here, we show that the vp3 protein synthesized in insect cells, either after expression of the complete polyprotein or from a vp3 gene construct, is proteolytically degraded, leading to the accumulation of product lacking the 13 c-terminal residues. this finding led to identification of the vp3 oligomerization domain within a 24-amino-acid stretch near the c-term ... | 2003 | 12743301 |
| structure-dependent efficacy of infectious bursal disease virus (ibdv) recombinant vaccines. | the immunogenicity and protective capability of several baculovirus-expressed infectious bursal disease virus (ibdv)-derived assemblies as vp2 capsids, vpx tubules and polyprotein (pp)-derived mixed structures, were tested. four-week-old chickens were immunised subcutaneously with one dose of each particulate antigen. vp2 icosahedral capsids induced the highest neutralising response, followed by pp-derived structures and then vpx tubules. all vaccinated animals were protected when challenged wit ... | 2003 | 12804866 |
| purification, crystallization and preliminary x-ray analysis of immunogenic virus-like particles formed by infectious bursal disease virus (ibdv) structural protein vp2. | infectious bursal disease virus (ibdv) causes a highly contagious disease in young chicks and leads to significant economic losses in the poultry industry. vp2 protein, which consists of 452 amino-acid residues, is the primary immunogen of ibdv and contains the epitopes responsible for eliciting neutralizing antibodies. when the chimeric vp2 protein (rvp2h) of a local ibdv strain p3009 was expressed alone using the baculovirus system, virus-like particles of approximately 23 nm in diameter forme ... | 2003 | 12832770 |
| hematology, plasma biochemistry, and serosurvey for selected infectious agents in southern giant petrels from patagonia, argentina. | in conjunction with reproductive and feeding ecology studies on southern giant petrels (sgp, macronectes giganteus) blood samples were collected for baseline health evaluations. twenty-five adult sgp from a breeding colony in chubut, argentina, were sampled during two consecutive breeding seasons, 1999-2000 (n = 15) and 2000-01 (n = 10). values for hematology, plasma biochemistry, and minerals are described for 20 birds in apparent good physical condition. a serologic survey of exposure to selec ... | 2003 | 12910764 |
| expression of vp2 gene protein of infectious bursal disease virus detected in korea. | the vp2 gene dna (1.4 kb in approximate) of a very virulent infectious bursal disease virus (vvibdv) chinju strain detected in chinju, korea was cloned into the bacmid, a baculovirus shuttle vector, through transposition of the gene from initially cloned pfastbachta plasmid, a baculovirus expression vector, and was subsequently expressed in spodoptera frugiperda (sf) cells. biological properties of the expressed vp2 subunit protein were characterized to aid in the development of genetically engi ... | 2003 | 12913360 |
| homotypic interactions of the infectious bursal disease virus proteins vp3, pvp2, vp4, and vp5: mapping of the interacting domains. | infectious bursal disease virus (ibdv), a nonenveloped double-stranded rna virus of chicken, encodes five proteins. of these, the rna-dependent rna polymerase (vp1) is specified by the smaller genome segment, while the large segment directs synthesis of a nonstructural protein (vp5) and a structural protein precursor from which the capsid proteins pvp2 and vp3 as well as the viral protease vp4 are derived. using the recently redefined processing sites of the precursor, we have reevaluated the ho ... | 2003 | 12919736 |
| effect of dietary mannan oligosaccharide on broiler breeder production traits and immunity. | the effects of mannan oligosaccharide (mos) supplementation in broiler breeder diets on egg production, hatchability, fertility, and immunity were examined by randomly allocating 60-wk-old breeders to eight replicates (four replicates of two diet treatments) in a cage trial, and 42-wk-old broiler breeders to 12 replicates (six replicates of two dietary treatments) in a deep litter trial. breeders were fed corn-soybean meal based diets with (mos group) or without mos or antibiotics (control group ... | 2003 | 12943304 |
| vaccination with e. coli recombinant empty viral particles of infectious bursal disease virus (ibdv) confer protection. | the a genome segment of the highly virulent infectious bursal disease virus (ibdv) was amplified using long and accurate-rt-pcr (la-rt-pcr). the entire sequence region encoding vp2, vp4, and vp3 in that order was cloned and sequenced. following subcloning into the escherichia coli expression vector pet21a under the t7 promoter, viral proteins were expressed and processed as demonstrated by western blot analysis. virus-like particles could be visualized by immuno-electron microscopy in iptg-induc ... | 2003 | 14501195 |
| characterization of infectious bursal disease virus isolates from indonesia indicates the existence of very virulent strains with unique genetic changes. | sequencing of the hypervariable region of viral protein vp2 of infectious bursal disease virus (ibdv) isolates obtained from non-vaccinated chickens in indonesia showed that the majority (16/17) were closely related to published very virulent (vv)ibdv strains. four isolates contained identical amino acid sequences to asian and european vvibdvs, sharing vv-specific amino acid residues 222(ala), 256(ile), and 294(ile). eight isolates differed by one amino acid at position 222(ala-->ser); however, ... | 2003 | 14522707 |
| sequence analysis of segment a of a field virus isolate from an outbreak of infectious bursal disease in india. | sequence analysis of genome segment a of an indian infectious bursal disease virus (ibdv) field isolate (kt1/99) revealed total 95 nucleotide substitutions, resulting in 17 amino acid changes. of these, five amino acid changes, namely f60s, t137i, i374v, v519i and e682d were unique to the kt1/99 isolate. the amino acid change p222a and the proposed hot mutation spot 680y, reported to be present in very virulent ibdv isolates were also found in kt1/99. this isolate had nucleotide divergence of 1. ... | 2003 | 14524472 |
| infectious bursal disease virus and proventriculitis in broiler chickens. | acute necrotic proventriculitis is a naturally occurring disease of broiler chickens that causes proventricular rupture during routine evisceration. although infectious bursal disease virus (ibdv) has been implicated, it has not been proven to be a direct cause of this disease. to further study the role of ibdv in proventriculitis, proventriculi and bursas were collected during both acute and chronic phases of naturally occurring proventriculitis and from chickens experimentally infected with se ... | 2003 | 14562897 |
| real-time reverse transcriptase-polymerase chain reaction detection and analysis of nucleotide sequences coding for a neutralizing epitope on infectious bursal disease viruses. | we used real-time reverse transcriptase (rt)-polymerase chain reaction (pcr) to detect infectious bursal disease virus (ibdv) strains. the lightcycler (roche) and hybridization probe system (roche, molecular biochemicals) were used. a mutation probe labeled with fluorescein and an anchor probe labeled with red-640 dye were prepared for each of the stc, del e, d78, and bursine 2 viral sequences. the mutation probes were designed to hybridize to nucleotides that encode the hydrophilic b region of ... | 2003 | 14562905 |
| development of a vaccine for immunization against classical as well as variant strains of infectious bursal disease virus using reverse genetics. | available ibdv vaccines based on classical ibdv strains do not induce full protection in the presence of maternally derived antibodies (mda) against variant strains. the aim of this study was the generation of an ibdv chimera between both classical and variant strains. characterization of the generated chimeric ibdv (d78-chim) was performed in both cell culture and susceptible chickens using the classical vaccine strain d78 for comparison. growth kinetics on cell culture showed that the d78-chim ... | 2003 | 14575776 |
| development and large-scale use of recombinant vp2 vaccine for the prevention of infectious bursal disease of chickens. | infectious bursal disease virus (ibdv) is the causative agent of gumboro disease, an infectious disease of global economic importance in poultry. one of the most effective types of inactivated ibdv vaccine is produced by infecting young chickens with a virulent strain, sacrificing them and extracting the virus from the bursa of fabricius. the goal of this study was to produce an effective subunit vaccine against ibdv thereby providing an effective means of combating the disease. in areas in whic ... | 2003 | 14585684 |
| mapping of conformational epitopes on capsid protein vp2 of infectious bursal disease virus by fd-tet phage display. | conformational epitopes on vp2 protein of infectious bursal disease virus (ibdv) were mapped using fd-tet phage display. a gene-targeted phage display library was made using dna fragments ranging approximately from 80 to 400 bp of the hypervariable region of the vp2 gene of ibdv strain 002-73, as neutralizing monoclonal antibodies against the vp2 protein recognize vp2 conformation-dependent epitopes within the hypervariable region. the phages were selected using immobilized monoclonal antibodies ... | 2003 | 14599686 |
| plasmid dna encoding antigens of infectious bursal disease viruses induce protective immune responses in chickens: factors influencing efficacy. | the complete polyprotein (vp2/4/3) and vp2 genes of two infectious bursal disease viruses (ibdvs) (one attenuated strain jd1 and one virulent strain zj2000) were amplified by long and accurate polymerase chain reaction (la-pcr), cloned, sequenced and inserted into plasmids pci and pcdna3 under the control of human cytomegalovirus (hcmv) immediate early enhancer and promoter. a series of dna vaccine preparations were made using liposome as the adjuvant to examine their immunogenicity. although vp ... | 2003 | 14609631 |
| research on infectious bursal disease--the past, the present and the future. | infectious bursal disease (ibd) virus (ibdv) is the etiological agent of "gumboro disease". although first observed about 40 years ago, this disease continues to pose an important threat to the commercial poultry industry. the emergence of antigenic variant as well as very virulent strains in vaccinated flocks considerably stimulated research efforts on both, ibd and ibdv. in this review, some of the recent advances in the understanding of the structure, morphogenesis and molecular biology of th ... | 2003 | 14637046 |
| sequence analysis of infectious bursal disease virus isolates from india: phylogenetic relationships. | prevalence of infectious bursal disease (ibd) among chickens in different parts of tamil nadu, india, has been studied by collection of bursal samples from suspected flocks and by performing reverse transcription-polymerase chain reaction (rt-pcr) for amplification of a specific product of 474 bp from the variable region of the vp2 gene. among 53 bursal samples examined by rt-pcr, 40 showed a positive reaction. the amplified products were subjected to nucleotide sequencing and the obtained seque ... | 2003 | 14658839 |
| isolates of infectious bursal disease virus from india are of very virulent phenotype. | four indian field isolates, a classical virulent and an attenuated vaccine strains of infectious bursal disease virus (ibdv) have been characterized by sequence analysis of part of the vp1 gene (from nucleotide 1538-1979) comprising one of viral rna dependent rna polymerase motifs. sequence alignment of these viruses with reported viruses of other countries revealed indian ibdv field isolates to be 100% similar to very virulent japanese (okym), european (uk661) and bangladesh (bd3/99) ibd viruse ... | 2003 | 14658846 |
| ability of lactococcus lactis to export viral capsid antigens: a crucial step for development of live vaccines. | the food grade bacterium lactococcus lactis is a potential vehicle for protein delivery in the gastrointestinal tract. as a model, we constructed lactococcal strains producing antigens of infectious bursal disease virus (ibdv). ibdv infects chickens and causes depletion of b-lymphoid cells in the bursa of fabricius and subsequent immunosuppression, morbidity, or acute mortality. the two major ibdv antigens, i.e., vp2 and vp3, that form the viral capsid were expressed and targeted to the cytoplas ... | 2003 | 14660377 |
| protection from infectious bursal disease virus (ibdv)-induced immunosuppression by immunization with a fowlpox recombinant containing ibdv-vp2. | immunosuppression resulting from infectious bursal disease virus (ibdv) infection has critical health and welfare implications for birds, yet it is incompletely understood and largely overlooked as a measure of vaccine efficacy. the ability of a fowlpoxvirus recombinant (fpibd1) containing the vp2 protein of ibdv to protect against ibdv-induced immunosuppression was investigated by measuring the convalescent chicken's ability to mount antibody responses to ibdv infection, and to inactivated ibdv ... | 2003 | 14676010 |
| efficacy of dna vaccines against infectious bursal disease virus in chickens enhanced by coadministration with cpg oligodeoxynucleotide. | the objective of the present study was to investigate the feasibility of a dna vaccine and cpg oligodeoxynucleotide (odn) to protect chickens against infectious bursal disease virus (ibdv) infection. two plasmids dna carrying vp2 genes of the very virulent (vv) strain of ibdv were constructed with reverse transcription-polymerase chain reaction and designated as pcdna3.1-vp2 and pci-vp2. the vp2 protein expressed in cos-7 cells transfected with the plasmid was confirmed by indirect immunofluores ... | 2003 | 14708976 |
| characterization of egyptian field strains of infectious bursal disease virus. | the reverse transcriptase-polymerase chain reaction/restriction fragment length polymorphism (rt-pcr/rflp) technique was used for identification and characterization of egyptian field strains of infectious bursal disease viruses (ibdvs) that caused severe outbreaks with (30%-60%) mortality rate. twenty-four bursal samples collected from 24 field outbreaks in commercially reared chicken flocks experiencing signs typical of infectious bursal disease (ibd) were used. ten of the bursal samples exami ... | 2003 | 14708996 |
| chicken anemia virus in broilers: dynamics of the infection in two commercial broiler flocks. | chicken anemia virus (cav) can cause a disease syndrome characterized by severe anemia, bone marrow atrophy, and severe immunosuppression in young chicks. maternal antibodies prevent these clinical signs but do not prevent infection, transmission of the virus, or immunosuppression. the clinical disease is rare today because of the widespread practice of vaccinating breeders, but the subclinical form of the disease is ubiquitous. the dynamics of cav infection, cav antibody responses, relative lym ... | 2003 | 14708998 |
| effects of early age feed restriction and heat conditioning on heat shock protein 70 expression, resistance to infectious bursal disease, and growth in male broiler chickens subjected to heat stress. | the effects of early age feed restriction and heat conditioning on heat shock protein (hsp) 70 expression, antibody production, resistance to infectious bursal disease (ibd), and growth of heat-stressed male broiler chickens were investigated. chicks were divided into 4 groups: 60% feed restriction on d 4,5, and 6 (fr); exposure to 36 +/- 1 degrees c for 1 h from d 1 to 21 (ht); combination of fr and ht (frht); and control. from d 35 to 50, heat stress was induced by exposing birds to 38 +/- 1 d ... | 2003 | 14717545 |
| blotched snakehead virus is a new aquatic birnavirus that is slightly more related to avibirnavirus than to aquabirnavirus. | by different approaches, we characterized the birnavirus blotched snakehead virus (bsnv). the sequence of genomic segment a revealed the presence of two open reading frames (orfs): a large orf with a 3,207-bp-long nucleotide sequence and a 417-nucleotide-long small orf located within the n-terminal half of the large orf, but in a different reading frame. the large orf was found to encode a polyprotein cotranslationally processed by the viral protease vp4 to generate pvp2 (the vp2 precursor), a 7 ... | 2003 | 12477876 |
| [establishment and biological properties of hybridoma cell lines secreting anti-ibdv idiotypic antibodies]. | in recent years, the prevention and cure of infectious bursal disease (ibd) have become more and more difficult due to the emergence of very virulent strains of infectious bursal disease virus (vvibdv) and the variant strains of ibdv. in this research, the hybridoma cell lines which secretes anti-idiotypic antibodies against anti-ibdv igg were established. according to the jerne's theory of immune network, the use of the anti-idiotypic antibodies as a vaccine will be a new method for the prevent ... | 2003 | 15969065 |
| identification of infectious bursal disease virus quasispecies in commercial vaccines and field isolates of this double-stranded rna virus. | quasispecies of infectious bursal disease virus (ibdv) vaccine and wild-type strains were identified using real-time rt-pcr at a region of the viral genome known for sequence variability. the lightcycler (idaho technology, inc.) and hybridization probe system (roche, molecular biochemicals) were used. an anchor probe labeled with lightcycler red 640 and mutation probe labeled with fluorescein were designed using the del-e ibdv sequence. the sequence of the mutation probe included nucleotides in ... | 2002 | 12490408 |
| evaluation of the immune response and detection of infectious bursal disease viruses by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay after in ovo vaccination of commercial broilers. | maternal immunity can interfere with infectious bursal disease virus (ibdv) vaccine efficacy. the effect of maternal antibody (macab) on the immune response and detection of two vaccine viruses, an ibdv immune complex (cx) and ibdv-2512, was investigated. vaccines were administered in ovo at 100 mean embryo infectious dose to commerical broiler embryos derived from young (29 wk) or old (63 wk) flocks. chickens with low matab were challenged with an antigenic standard ibdv strain at 21 and 35 day ... | 2002 | 12495039 |
| immunosuppression in specific-pathogen-free broilers administered infectious bursal disease virus vaccines by in ovo route. | the effect of two infectious bursal disease virus (ibdv) vaccines (ibdv-immune complex [icx] and ibdv-2512), administered in ovo, on the cell-mediated immunity of specific-pathogen-free (spf) broilers was examined. a decrease (p < 0.05) in the t-cell mitogenic response occurred in birds vaccinated with both vaccines on days 9 and 21 post in ovo vaccination (piov), but an increase (p < 0.05) occurred on day 15 piov. the t cells from birds given the ibdv-2512 were less responsive. there were no si ... | 2002 | 12495040 |
| molecular characterization of spanish infectious bursal disease virus field isolates. | nine spanish isolates of infectious bursal disease virus (ibdv) were characterized and classified after reverse transcriptase-polymerase chain reaction of a 248-bp fragment of the vp2 gene hypervariable region and restriction fragment length polymorphism (rflp). the restriction endonucleases (res) used were bstni, sad, sspi, taqi, drai, and styi. sequencing of the amplified product and further comparison of these sequences with published sequence data from other ibdv strains were also performed. ... | 2002 | 12495046 |
| comparison of a putative second serotype of chicken infectious anemia virus with a prototypical isolate i. pathogenesis. | ciav-7 is a virus with similar pathogenic and physicochemical characteristics to, but antigenically distinct from, chicken infectious anemia virus (ciav). the pathogenesis of ciav-7 was evaluated in a comparative study with a representative isolate of ciav, the del-ros strain. the pathogenesis of ciav-7 was similar to del-ros on the basis of the clinical disease induced and gross and microscopic lesions, although ciav-7 produced fewer and less severe lesions overall. a second comparative pathoge ... | 2002 | 12495056 |
| pathogenicity of embryo-adapted serotype 2 oh strain of infectious bursal disease virus in chickens and turkeys. | the pathogenicity of serotype 2 oh strain of infectious bursal disease virus (ibdv) to specific-pathogen-free (spf) chicken embryos and 2-wk-old spf chickens and turkey poults was investigated. the virus was pathogenic for chicken embryos after five passages as evidenced by pathologic changes in inoculated embryos. the embryo-adapted virus was not pathogenic for 2-wk-old spf chickens and turkey poults as indicated by lack of clinical signs, gross or microscopic lesions in the bursa of fabricius ... | 2002 | 12495064 |
| virulent vaccine strains of infectious bursal disease virus not distinguishable from wild-type viruses with marker the use of a molecular. | molecular techniques have not only made timely and accurate detection of infectious bursal disease viruses (ibdvs) possible but also have allowed the identification of viral strains. previously, we identified a genetic marker that distinguished wild-type ibdv strains from vaccine strains of the virus. the marker was an ngom iv restriction enzyme site in the vp2 gene that was present in 10 wild-type viruses but not 16 vaccine strains of ibdv. on the basis of that study, we concluded that the ngom ... | 2002 | 12495070 |
| the localization and uptake of in ovo injected soluble and particulate substances in the chicken. | the localization of in ovo injected substances in the chicken was investigated. we determined that localization is dependent on the nature of substances and the time of in ovo injection. in ovo injections with soluble bromodeoxyuridin (brdu), particulate colloidal carbon, 40 nm fluorescent microspheres, and live infectious bursal disease virus (ibdv) were performed with a 25-mm (1-in) needle at days 16 and 18 of incubation (di-16 and di-18, respectively). localization of injected substances was ... | 2002 | 12512571 |
| antigenic and molecular characterization of recent infectious bursal disease virus isolates in china. | eleven infectious bursal disease virus (ibdv) strains isolated recently from china were compared with the early classical virulent strain cj801, the chicken embryo fibroblast-adapted (cef) variant strain gz902, and the attenuated vaccine strains bj836, bk912, and lm to discern the evolutionary characteristics of ibdv in china at both antigenic and genetic levels. virus neutralization (vn) assay showed that all ten very virulent (vv) ibdv strains belong to the same subtype as attenuated strains, ... | 2002 | 12018704 |
| molecular cloning and characterization of antheraea mylitta cytoplasmic polyhedrosis virus genome segment 9. | genome segment 9 of the 11-segment rna genomes of three cytoplasmic polyhedrosis virus (cpv) isolates from antheraea mylitta (amcpv), antheraea assamensis (aacpv) and antheraea proylei (apcpv) were converted to cdna, cloned and sequenced. in each case, this genome segment consists of 1473 nucleotides with one long orf of 1035 bp and encodes a protein of 345 amino acids, termed nsp38, with a molecular mass of 38 kda. secondary structure prediction showed the presence of nine alpha-helices in the ... | 2002 | 12029164 |
| major histocompatibility complex-linked immune response of young chickens vaccinated with an attenuated live infectious bursal disease virus vaccine followed by an infection. | the influence of the mhc on infectious bursal disease virus (ibdv) vaccine response in chickens was investigated in three different chicken lines containing four different mhc haplotypes. two mhc haplotypes were present in all three lines with one haplotype (b19) shared between the lines. line 1 further contains the bw1 haplotype isolated from a red jungle fowl. line 131 further contains the b131 haplotype isolated from a meat-type chicken. finally, line 21 further contains the international b21 ... | 2002 | 12033414 |
| detection of infectious bursal disease virus in different lymphoid organs by single-step reverse transcription polymerase chain reaction and microplate hybridization assay. | a rapid and sensitive method for the detection of infectious bursal disease virus (ibdv) rna in different chicken lymphoid organs was developed. the method is based on a single-step reverse transcription polymerase chain reaction (rt-pcr) procedure and the enzyme-linked immunosorbent assay (elisa) detection method of amplified products. vaccinal ibdv strain and field isolates were used for the optimization of rt-pcr and for the determination of conditions for microplate hybridization and colorim ... | 2002 | 12033682 |
| chicken anemia virus and infectious bursal disease virus interfere with transcription of chicken ifn-alpha and ifn-gamma mrna. | chicken anemia virus (cav) and infectious bursal disease virus (ibdv) are the two most important viruses that cause immunosuppression in commercial chickens. because inapparent, subclinical infections by these viruses cause immunosuppression, there is need for assessment of the immune status of chickens. interference with induction of transcription for chicken interferon-alpha (chifn-alpha) and chifn-gamma was noted after subclinical infections with either cav or ibdv. because the immunosuppress ... | 2002 | 12034026 |
| egyptian propolis: 2. chemical composition, antiviral and antimicrobial activities of east nile delta propolis. | three propolis samples from east nile delta, egypt were collected. propolis samples were investigated by gc/ms,103 compounds were identified, 20 being new for propolis. dakahlia propolis was a typical poplar propolis but it contained two new caffeate esters and two new triterpenoids. ismailia propolis was characterized by the presence of new triterpenic acid methyl esters and it did not contain any aromatic acids, esters and flavonoids. sharkia propolis was characterized by the presence of caffe ... | 2002 | 12064745 |
| birnavirus vp1 proteins form a distinct subgroup of rna-dependent rna polymerases lacking a gdd motif. | we have cloned and characterized the drosophila x virus (dxv) genome segment b and its encoded vp1, the putative rna-dependent rna polymerase (rdrp) present in the virion. the 2991-bp open reading frame encodes the largest birnavirus vp1 at 977 aa, with a calculated m(r) of 112.8 kda. as with the vp1 proteins of the type species of the other two genera in the family birnaviridae, namely, infectious pancreatic necrosis virus (genus aquabirnavirus) and infectious bursal disease virus (genus avibir ... | 2002 | 12069523 |
| intentional coinfection of patients with hcv infection using avian infection bursal disease virus. | 2002 | 12085374 | |
| characterisation of an indonesian very virulent strain of infectious bursal disease virus. | an indonesian very virulent (vv) strain of infectious bursal disease virus (ibdv), designated tasik94, was characterised both in vivo and at the molecular level. inoculation of tasik94 into 5-week-old specific-pathogen-free (spf) chickens resulted in 100% morbidity and 45% mortality. the complete nucleotide and predicted amino acid sequences of genomic segments a and b were determined. across each of the three deduced open reading frames (orfs), tasik94 shared the greatest nucleotide homology to ... | 2002 | 12111410 |
| sequence and phylogenetic analysis of the vp2 gene of very virulent infectious bursal disease virus isolates. | previously we have shown that very virulent infectious bursal disease viruses (vvibdv) that are sspi, taqi and styi positive (92/04, 97/61 and 94/b551) but not sspi and taqi positive and styi negative (94/273) cause high mortality, up to 80% in specific-pathogen-free chickens with significant damage of the bursal as well as nonbursal tissues. in this study, we sequenced the vp2 gene (1351 bp) of the 92/04, 94/273 and 94/b551 and compared them with other ibdv strains. all the isolates have the un ... | 2002 | 12186763 |
| a novel transcutaneous plasmid-dimethylsulfoxide delivery technique for avian nucleic acid immunization. | in this report, we show that dimethylsulfoxide (dmso) enhances liposome-mediated transfection of nucleic acid in chicken macrophage cells and that this could be exploited for the transcutaneous delivery of naked dna through the intact skin of chickens. we found that dmso enhanced transfection efficiencies of lipofectamine and polyethyleneimine in hd-11 chicken macrophage cells. based on this principle, we showed that transcutaneous delivery of a dna plasmid-dimethylsulfoxide mixture (1:1) to unt ... | 2002 | 12208052 |
| exchange of the c-terminal part of vp3 from very virulent infectious bursal disease virus results in an attenuated virus with a unique antigenic structure. | infectious bursal disease virus (ibdv) is the major viral pathogen in the poultry industry. live attenuated serotype 1 vaccine strains are commonly used to protect susceptible chickens during their first 6 weeks of life. wild-type serotype 1 ibdv strains are highly pathogenic only in chickens, whereas serotype 2 strains are apathogenic in chickens and other birds. here we describe the replacement of the genomic double-stranded rna (dsrna) encoding the n- or c-terminal part of vp3 of serotype 1 v ... | 2002 | 12239311 |
| quantitative measures of disease in broiler breeder chicks of different major histocompatibility complex genotypes after challenge with infectious bursal disease virus. | criteria for evaluating genetic differences in resistance and susceptibility to infectious bursal disease (ibd) within a commercial broiler breeder line of chickens were compared. line a broiler breeder chickens were challenged with graded doses of animal and plant health inspection service (aphis) strain ibd virus (ibdv) and evaluated at 2 time points, 3 days postinoculation (pi) and 10 days pi. measures obtained at both time points included bursa to body weight, bursa histology, bursa lymphocy ... | 2002 | 12243521 |
| field trial in commercial broilers with a multivalent in ovo vaccine comprising a mixture of live viral vaccines against marek's disease, infectious bursal disease, newcastle disease, and fowl pox. | a multivalent in ovo vaccine (miv) was tested for safety and efficacy in a commercial broiler complex. the miv comprised five replicating live viruses including serotypes 1, 2, and 3 of marek's disease virus (mdv), an intermediate infectious bursal disease virus (ibdv) and a recombinant fowl poxvirus (fpv) vector vaccine containing hn and f genes of newcastle disease virus (ndv). the performance of miv-vaccinated broilers was compared with that of hatchmates that received turkey herpesvirus (hvt ... | 2002 | 12243525 |
| hypoglycemia spiking mortality syndrome in broilers with rickets and a subsequent investigation of feed restriction as a contributing factor. | several cases of elevated mortality with neurologic signs in 14-to-16-day-old broilers were presented to the poultry diagnostic and research center from one local integrated company. suspected of "spiking mortality" associated with hypoglycemia, blood glucose levels were <150 mg/dl overall, with several birds with blood glucose levels as low as 30 mg/dl. tissues, submitted for histopathology, revealed rickets in 50% of the birds. virus isolation and serology for reovirus and infectious bursal di ... | 2002 | 12243543 |
| anti-idiotypic antibody specific for an infectious bursal disease virus-neutralizing monoclonal antibody does not interfere with the virus infection. | infectious bursal disease virus (ibdv) capsid protein, vp2, contains a hypervariable domain that is recognized by virus-neutralizing antibodies. the virus-neutralizing epitope is highly conformation-dependent and the domain is speculated to be involved in the virus-target cell interaction. in this study, a polyclonal anti-idiotypic antibody (anti-id) was generated by the sequential immunization of a rabbit with a virus-neutralizing monoclonal antibody gi-11 which recognizes the vp2 hypervariable ... | 2002 | 12376762 |
| the value of tissue imprint hybridization for rapid detection of infectious bursal disease virus from field outbreaks. | the use of a peroxidase labelled pcr generated probe followed by enhanced chemiluminescence hybridization assay detected infectious bursal disease virus directly from bursal imprints on a nylon membrane. tissue imprint hybridization proved to be a simple, rapid and safe means of detecting ibd virus for screening large numbers of field samples. the pcr generated probe was highly specific for ibd virus and did not hybridize with cellular nucleic acids in control imprints. tissue imprint hybridizat ... | 2002 | 12379057 |
| protective immunity against infectious bursal disease virus in chickens in the absence of virus-specific antibodies. | the role of cell-mediated immunity (cmi) in pathogenesis of infectious bursal disease virus (ibdv) was investigated. one-day-old specific pathogen-free chickens were treated with 3mg of cyclophosphamide (cy) per chicken for 4 consecutive days and, 3 weeks later, infected with the ibdv-im strain. chickens were examined for: (a) mitogenic response of splenocytes to cona, as an indicator of t-cell functions in vitro, (b) antibody against ibdv by elisa, (c) ibdv genome in various tissues by rt-pcr a ... | 2002 | 12383646 |
| the role of t cells in protection by an inactivated infectious bursal disease virus vaccine. | the current belief is that the humoral immune response plays the principal role in defense against virulent infectious bursal disease virus (ibdv). in this study we used a model, in which chickens were compromised in functional t cells by neonatal thymectomy and cyclosporin a (txcsa) treatment, to demonstrate the role of t cells in protective immunity against ibdv. we demonstrated that t cells were necessary to achieve full protection against virulent ibdv. when t cell compromised txcsa-treated ... | 2002 | 12383647 |
| [expression of polyprotein of infectious bursal disease virus in bombyx mori]. | segment a of the genome of infectious bursal disease virus(ibdv) encodes structure protein vp2 and vp3 and protease vp4. in this study a polyprotein gene of ibdv was inserted into a bombyx mori baculovirus transfer vector pachlt--c and contransfected into bmn cells with linear genome dna of virus bm-bacpak6. dot hybridization suggested that the segment a of the virus genome was inserted in the genome of bm-bacpak6. the silkworm of fifth instars were infected by the recombinant virus and the immu ... | 2002 | 12385246 |
| nucleotide sequence analysis of variable region of vp2 gene of two infectious bursal disease virus isolates from commercial poultry farms. | two infectious bursal disease virus (ibdv) isolates were obtained from commercial poultry farms with a history of severe outbreaks. a 474-bp product encompassing hypervariable region of ibdv vp2 gene was amplified by reverse transcription-polymerase chain reaction (rt-pcr). the nucleotide sequences of two isolates, vmb1 and vmb2, were determined and compared with those of twenty ibdv strains, including seven very virulent, four classical virulent, four classical attenuated, three antigenic varia ... | 2002 | 12387501 |
| infectious bursal disease virus capsid protein vp3 interacts both with vp1, the rna-dependent rna polymerase, and with viral double-stranded rna. | infectious bursal disease virus (ibdv) is a double-stranded rna (dsrna) virus of the birnaviridae family. its two genome segments are encapsidated together with multiple copies of the viral rna-dependent rna polymerase, vp1, in a single-shell capsid that is composed of vp2 and vp3. in this study we identified the domains responsible for the interaction between vp3 and vp1. using the yeast two-hybrid system we found that vp1 binds to vp3 through an internal domain, while vp3 interacts with vp1 so ... | 2002 | 12388690 |
| susceptibility of vaccinated and unvaccinated egyptian chickens to very virulent infectious bursal disease virus. | the responses of vaccinated and unvaccinated chickens of different breeds to infection with very virulent infectious bursal disease virus (vvibdv) were investigated. five-week-old chickens of five egyptian breeds (fayoumi, balady, golden, mandarah, and gimmizah), and foreign white leghorn pullets were tested. in unvaccinated birds, mortality, relative bursa and spleen weight, bursal lesion score, antibody titres and the response of blood lymphocytes to mitogens were examined. the gimmizah and fa ... | 2002 | 12396359 |
| risk factors associated with the introduction of acute clinical infectious bursal disease among danish broiler chickens in 1998. | the objective of the present study was to investigate risk factors associated with the introduction of acute clinical infectious bursal disease (ibd) among danish broiler chickens in 1998. data on 218 flocks were collected from hatcheries, abattoirs, farmers and veterinarians; 49 of the flocks had experienced acute clinical ibd (cases), 169 were unexposed (controls). the study was carried out using a case-control design. cases were defined as the first flock on each premises to experience acute ... | 2002 | 12425789 |
| characterization of the antigenic, immunogenic, and pathogenic variation of infectious bursal disease virus due to propagation in different host systems (bursa, embryo, and cell culture). i. antigenicity and immunogenicity. | in vitro and in ovo virus neutralization assays were conducted to assess the role of different host systems in infectious bursal disease virus (ibdv) antigenic and immunogenic variation. four different strains, two variant (1084 e and gls) and two standard (edgar and stc), were propagated separately in the bursa of fabricius and embryos, and were compared with cell culture-adapted preparations of the homologous strains. chicken polyclonal antisera were prepared against each ibdv and neutralizing ... | 2002 | 12427340 |
| characterization of the antigenic, immunogenic, and pathogenic variation of infectious bursal disease virus due to propagation in different host systems (bursa, embryo, and cell culture). ii. antigenicity at the epitope level. | antigenic variation of infectious bursal disease virus (ibdv) due to propagation in different host systems (bursa of fabricius, embryos, or cell cultures) was determined by enzyme-linked immunosorbent assay (indirect and antigen capture) and western blot analysis. to conduct this study, we used 27 non-neutralizing anti-vp(2) monoclonal antibodies, a reference panel of nine neutralizing monoclonal antibodies, and 13 neutralizing anti-ibdv chicken polyclonal antibodies. changes occurred in neutral ... | 2002 | 12427341 |
| characterization of the antigenic, immunogenic, and pathogenic variation of infectious bursal disease virus due to propagation in different host systems (bursa, embryo, and cell culture). iii. pathogenicity. | differences in the relative pathogenicity of variant (1084 e and gls) and standard (edgar and stc) infectious bursal disease virus (ibdv) strains were observed after propagation in the bursa of fabricius, embryos, or cell cultures. bursa-derived ibdv induced the most severe lesions in the bursa of fabricius when compared with strains propagated in embryos or cell cultures. embryo-derived ibdv induced moderate gross bursal lesions, whereas cell culture-derived ibdv did not damage the bursa grossl ... | 2002 | 12427342 |
| confirmation of the existence of two distinct genetic groups of infectious bursal disease virus in australia. | to characterise infectious bursal disease viruses (ibdvs) prevalent at major commercial sites throughout australia and to compare the nucleic acid sequences of local strains of ibdv with those of characterised overseas strains. | 2002 | 12465828 |
| alteration of amino acids in vp2 of very virulent infectious bursal disease virus results in tissue culture adaptation and attenuation in chickens. | reverse genetics technology offers the possibility to study the influence of particular amino acids of infectious bursal disease virus (ibdv) on adaptation to tissue culture. genomic segments a and b of the very virulent (vv) ibdv field strain uk661 were completely cloned and sequenced, and the strain was rescued from full-length cdna copies of both segments (uk661rev). using site-directed mutagenesis, alteration of a single amino acid in the segment a-encoded vp2 (a284t) resulted in a limited c ... | 2002 | 11752708 |
| the maturation process of pvp2 requires assembly of infectious bursal disease virus capsids. | infectious bursal disease virus (ibdv) is a nonenveloped avian virus with a two-segment double-stranded rna genome. its t=13 icosahedral capsid is most probably assembled with 780 subunits of vp2 and 600 copies of vp3 and has a diameter of about 60 nm. vp1, the rna-dependent rna polymerase, resides inside the viral particle. using a baculovirus expression system, we first observed that expression of the pvp2-vp4-vp3 polyprotein encoded by the genomic segment ibda results mainly in the formation ... | 2002 | 11836416 |
| the capsid of infectious bursal disease virus contains several small peptides arising from the maturation process of pvp2. | the capsid proteins vp2 and vp3 of infectious bursal disease virus, a birnavirus, are derived from the processing of a large polyprotein: nh2-pvp2-vp4-vp3-cooh. although the primary cleavage sites at the pvp2-vp4 and vp4-vp3 junctions have been identified, the proteolytic cascade involved in the processing of this polyprotein is not yet fully understood, particularly the maturation of pvp2. by using different approaches, we showed that the processing of pvp2 (residues 1 to 512) generated vp2 and ... | 2002 | 11836417 |
| fate of plasmid dna encoding infectious bursal disease virus vp2 capsid protein gene after injection into the pectoralis muscle of the chicken. | the objective of this study was to determine whether recombinant plasmid dna injected intramuscularly into chickens expressed the gene of interest in vivo and could be subsequently detected in primary and secondary lymphoid tissues with polymerase chain reaction (pcr). the vp2 capsid protein gene of the standard challenge strain (stc) of infectious bursal disease virus (ibdv) was cloned into a eukaryotic plasmid, and purified dna was prepared. fourteen 2-wk-old chickens were injected in the pect ... | 2002 | 11873829 |
| site-directed mutagenesis of avibirnavirus vp4 gene. | virus protein vp4 of infectious bursal disease virus (ibdv) is a protease which separates vpx and vp3 from the polyprotein. we studied the importance of serine and aspartic acid on cleavage at the vpx/vp4 junction and analysed the role of the proposed h547, d590, and s653 catalytic site using five different mutations on vp4. our results suggest that the replacement of serine by lysine in axaas motifs in serotype ii ibdv influences polyprotein (pp) processing by vp4 and also indicate the presence ... | 2002 | 11878927 |
| a simple method for screening bacterial colonies for mutagenized sites in plasmid dna. | because of the multiple-step process that is involved in the detection of mutagenized restriction enzyme sites in plasmid dna, a simple and accurate method was developed to analyse the plasmid dna of site-directed mutagenesis experiments from bacterial colonies. the desired mutated part is located between the eco ri restriction site on puc19. two mutagenic primers were designed to replace only one nucleotide on segments a and b of the bi-segmented genome of infectious bursal disease virus (ibdv) ... | 2002 | 11684307 |
| role of intrabursal t cells in infectious bursal disease virus (ibdv) infection: t cells promote viral clearance but delay follicular recovery. | infectious bursal disease virus (ibdv) induces an acute, highly contagious immunosuppressive disease in young chickens. we examined the role of t cells in ibdv-induced immunopathogenesis and tissue recovery. t cell-intact chickens and birds compromised in their t cell function by a combination of surgical thymectomy and cyclosporin a treatment (tx-csa) were infected with an intermediate vaccine strain of ibdv (bursine 2, fort dodge). our data revealed that functional t cells were needed to contr ... | 2002 | 11890524 |
| genetic and phenotypic correlations between antibody responses to escherichia coli, infectious bursa disease virus (ibdv), and newcastle disease virus (ndv), in broiler lines selected on antibody response to escherichia coli. | the genetic control of antibody (ab) response to escherichia coli (ec), infectious bursa disease virus, and newcastle disease virus and the genetic and phenotypic correlation between these ab responses, were evaluated under farm conditions in which chicks were simultaneously exposed to these antigens. the experimental population comprised five groups: two lines divergently selected for high (hh) or low (ll) ab response to ec vaccination; a commercial broiler dam-line (cc), from which hh and ll h ... | 2002 | 11902404 |
| changes in serum ovotransferrin levels in chickens with experimentally induced inflammation and diseases. | a competitive enzyme immunoassay was developed to measure the changes in serum levels of ovotransferrin (otf) during inflammation and infectious diseases in chickens. the assay is based on the competition of serum otf with a fixed concentration of biotin-labeled otf to bind to a rabbit anti-chicken transferrin antibody immobilized on microtiter wells. after several washing steps, the antibody-bound biotinylated otf is probed with streptavidin-horseradish peroxidase conjugate (hrp) followed by a ... | 2002 | 11922323 |
| pathogenesis and tissue distribution of a variant strain of infectious bursal disease virus in commercial broiler chickens. | the detection of either infectious virus, viral antigen, and/or viral rna in different tissues of commercial broilers inoculated at 1 day of age with e/del variant strain of infectious bursal disease virus (ibdv) was investigated at 2, 4, and 6 wk postinoculation (pi). virus was readily isolated from homogenates of bursa, cecal tonsils, and bone marrow at 2 and 4 wk pi. virus isolation coupled with immunoperoxidase assay or reverse transcription-polymerase chain reaction for ibdv-specific rna ex ... | 2002 | 11922329 |
| complete, long-lasting protection against lethal infectious bursal disease virus challenge by a single vaccination with an avian herpesvirus vector expressing vp2 antigens. | marek's disease herpesvirus is a vaccine vector of great promise for chickens; however, complete protection against foreign infectious diseases has not been achieved. in this study, two herpesvirus of turkey recombinants (rhvts) expressing large amounts of infectious bursal disease virus (ibdv) vp2 antigen under the control of a human cytomegalovirus (cmv) promoter or cmv/beta-actin chimera promoter (pec promoter) (rhvt-cmvvp2 and rhvt-pecvp2) were constructed. rhvt-pecvp2, which expressed the v ... | 2002 | 11991992 |
| restriction fragment length polymorphism analysis of the vp2 gene of australian strains of infectious bursal disease virus. | twenty-four australian strains of infectious bursal disease virus (ibdv) were characterized by reverse transcription/polymerase chain reaction-restriction fragment length polymorphism and compared with previously published overseas strains. a primer pair designed to amplify a 743 base pair fragment of the vp2 gene was used and restriction fragment length polymorphism profiles were determined for each strain using three restriction enzymes, bst ni, mboi and sspi. australian strains comprised 12 m ... | 2002 | 12593738 |
| early stages of infectious bursal disease virus infection in chickens detected by in situ reverse transcriptase-polymerase chain reaction. | two infectious bursal disease virus (ibdv) strains were inoculated both intranasally and by eye drop into 5-week-old specific pathogen free chickens. the bursa, the liver, the kidney, the spleen, the thymus, the caecal tonsil and the thigh muscle were harvested at 4, 8, 16, 28, 40, 56, 72, 96 h post-inoculation (p.i.) for ibdv detection by in situ reverse transcriptase-polymerase chain reaction and, at the same time, the pathological changes in these tissues were investigated. a typical positive ... | 2002 | 12593743 |