Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| preparation of chil-2 and ibdv vp2 fusion protein by baculovirus expression system. | this study aims to produce an effective subunit vaccine against infectious bursal disease virus (ibdv). the genes of chicken interleukin-2 (chil-2) and ibdv viral protein 2 (vp2) were amplified and fused by splice overlap extension-polymerase chain reaction (soe-pcr). the fusion gene was digested by ecor i/kpn i and inserted into pbacpak8 vector, resulting in recombinant transfer plasmid pbacpakvp2-il2. the recombinant plasmid was transfected into sf-9 cells accompanied with hybrid nuclear polyh ... | 2005 | 16212892 |
| vaccination against very virulent infectious bursal disease virus using recombinant t4 bacteriophage displaying viral protein vp2. | in order to develop a desirable inexpensive, effective and safe vaccine against the very virulent infectious bursal disease virus (vvibdv), we tried to take advantage of the emerging t4 bacteriophage surface protein display system. the major immunogen protein vp2 from the vvibdv strain hk46 was fused to the nonessential t4 phage surface capsid protein, a small outer capsid (soc) protein, resulting in the 49 kda soc-vp2 fusion protein, which was verified by sodium dodecylsulfate polyacrylamide ge ... | 2005 | 16215632 |
| temporal and spatial analysis of the 1999 outbreak of acute clinical infectious bursal disease in broiler flocks in denmark. | the objective of this study was to describe the spatial and temporal dynamics of the 1999 outbreak of acute clinical infectious bursal disease (ibd) in broiler chicken farms in denmark. the analysis was performed using data from all broiler farms located in the jutland peninsula and the island of funen (168 municipalities). the moran's index i, k-functions and scan statistics were used to describe the dynamics of the epidemic. in addition, spatially correlated survival analyses were performed an ... | 2005 | 16227094 |
| viral genotyping of infectious bursal disease viruses isolated from the 2002 acute outbreak in spain and comparison with previous isolates. | an infectious bursal disease (ibd) outbreak occurred in the east region of spain in the spring of 2002 and rapidly spread thorough the whole country, although proper vaccination programs were applied. in this report, 33 infectious bursal disease viruses (ibdvs) isolated from this outbreak were characterized by nucleotide sequencing of the vp2 gene hypervariable region and were compared with reference ibd strains and the 1990s spanish ibdvs in order to determine possible emergence of ibdv isolate ... | 2005 | 16252484 |
| reproduction of proventriculitis in commercial and specific-pathogen-free broiler chickens. | proventriculitis was studied by experimentally reproducing the disease in broiler chickens. one-day-old infectious bursal disease virus (ibdv) and infectious bronchitis virus (ibv) antibody positive commercial broilers and 1-day-old antibody negative specific-pathogen-free (spf) broilers were orally gavaged with proventricular homogenates produced from the proventriculi of broilers with proventriculitis. at 7 and 14 days, both commercial and spf broilers had enlargement of the proventriculus wit ... | 2005 | 16252487 |
| intracellular interference of infectious bursal disease virus. | a search for dominant-negative mutant polypeptides hampering infectious bursal disease virus (ibdv) replication has been undertaken. we have found that expression of a mutant version of the vp3 structural polypeptide known as vp3/m3, partially lacking the domain responsible for the interaction with the virus-encoded rna polymerase, efficiently interferes with the ibdv replication cycle. transformed cells stably expressing vp3/m3 show a significant reduction (up to 96%) in their ability to suppor ... | 2005 | 16254378 |
| detection of vvibdv in vaccinated spf chickens. | the purpose of our experiment was to investigate, if apparently healthy, vaccinated chickens may be involved in maintaining and spreading infectious bursal disease virus (ibdv) in poultry environments. we aimed at simultaneous detection and identification of very virulent field strain ibdv (vvibdv) as well as vaccine strain ibdv in experimentally infected chickens. two groups of specific pathogen free (spf) chickens were vaccinated using the intermediate infectious bursal disease (ibd) vaccine d ... | 2005 | 16398333 |
| genotyping of infectious bursal disease virus strains by restriction fragment length polymorphism analysis of the vp1, vp2, and vp3 genes. | summary. this study aimed to genotype infectious bursal disease virus (ibdv) isolates from the minas gerais state poultry industry. rna was extracted from bursae obtained from field cases without passage or commercial vaccines. genetic subtyping of ibdv isolates and vaccine strains was carried out by the reverse transcriptase-polymerase chain reaction (rt-pcr) and restriction fragment length polymorphism (rflp) analysis. a 588-bp fragment in the vp1 gene, an 847-bp fragment in the vp2 gene, and ... | 2005 | 16404990 |
| detection of infectious bursal disease virus in various lymphoid tissues of experimentally infected specific pathogen free chickens by different reverse transcription polymerase chain reaction assays. | infectious bursal disease (ibd) is a worldwide distributed immunosuppressive viral disease in young chickens, controlled by vaccination. emergence of several strains of ibd virus (ibdv) has created a demand for strain-specific diagnostic tools. in the present experiment, five different reverse transcription polymerase chain reaction (rt-pcr) assays, including two recently developed strain-specific assays, were employed for detection of ribonucleic acid (rna) from three different ibdv strains in ... | 2005 | 16404995 |
| significance of the genetic relationships deduced from partial nucleotide sequencing of infectious bursal disease virus genome segments a or b. | the rapid genomic characterization of infectious bursal disease virus (ibdv) requires determining which partial nucleotide (nt) sequences derived from ibdv segments a or b would produce phylogenetic information as significant as sequencing the whole corresponding segments. long nt coding sequences of 27 ibdv segments a (aa 20-991) and 21 segments b (aa 7-stop codon) were retrieved from databanks and used to compute reference phylogenetic trees using neighbor joining (nj) and parsimony (p): clust ... | 2005 | 15503222 |
| synthesis of reassortant infectious bursal disease virus in chickens injected directly with infectious clones from different virus strains. | the infectious bursal disease virus (ibdv), a member of the birnaviridae family, containing a bisegmented double-stranded rna genome, encodes four structural viral proteins, vp1, vp2, vp3, and vp4, as well as a non-structural protein, vp5. in the present paper, the segment a from two ibdv strains, field isolate zj2000 and attenuated strain hz2, were inserted into one naei site by site-directed silent mutagenesis and subcloned into the eukaryotic expression plasmid pci under the control of the hu ... | 2005 | 15756422 |
| enhanced immunopathology induced by very virulent infectious bursal disease virus. | immunohistochemical and flow cytometric analyses of the bursa, spleen and thymus following infection with the very virulent infectious bursal disease virus (vvibdv) strain uk661 revealed discrete differences from classical virulent infectious bursal disease virus strains. bu-1+, immunoglobulin (ig)m+ and igg+ cells were all depleted from the bursa, spleen and thymus, suggesting loss of both immature and mature b lymphocytes. small numbers of bu-1+ cells repopulated the bursa 14 days post-infecti ... | 2005 | 15763733 |
| early and transient induction of nitric oxide (no) in infectious bursal disease virus infection is t-cell dependent: a study in cyclosporin-a treated chicken-model. | the level of nitric oxide (no) in the supernatants of mitogen (pha) stimulated lymphocyte cultures from infectious bursal disease (ibd) virus infected t-cell suppressed and immune competent chickens was monitored. the immune competent chickens when infected with ibd virus showed 4-6 folds increased levels of no as compared to uninfected chickens. the levels of no in t-cell suppressed chickens were comparable to uninfected control chickens, in spite of markedly increased hemorrhage suggesting tha ... | 2005 | 15782823 |
| infectious bursal disease virus-induced immunosuppression in the chick is associated with the presence of undifferentiated follicles in the recovering bursa. | infectious bursal disease virus (ibdv) causes an acute cytolytic infection in chicken b lymphocytes resulting in destruction of the b-cell population. most severe depletion occurs in the bursa of fabricius, where the immunoglobulin repertoire is developed by gene conversion. chicks surviving ibdv infection are immunosuppressed despite repopulation of the bursa with b cells. here we show that infection of neonatal chicks with a classical virulent ibdv strain (f52/70) causes severe bursal bcell de ... | 2005 | 15802957 |
| pigeon paramyxovirus: association with common avian pathogens in chickens and serologic survey in wild birds. | pigeon paramyxovirus-1 (ppmv-1) was isolated from pigeons from east-central alabama and used in association with chicken anemia virus (cav), infectious bursal disease virus (ibdv), or finch mycoplasma gallisepticum (mg) in specific-pathogen-free chickens to assess dinical disease and pathology. ppmv-1 infection in all groups was conducted at day 10 of age via the ocular route. the low passage ppmv-1 isolate was inoculated into chickens in different groups at 10 days post-cav infection, 6 days po ... | 2005 | 15839419 |
| interference between mild and pathogenic strains of infectious bursal disease virus in chickens. | infectious bursal disease virus is a contagious, immunosuppressive disease of young chickens that is controlled by vaccination. cross-protection occurs between different strains of the virus as a result of shared neutralizing epitopes. however, interactions between two antigenically similar strains (a mild and a pathogenic) coinfecting the same host have not been investigated. groups of specific-pathogen-free chickens were inoculated with a mild strain followed by a pathogenic strain at 0, 16, 2 ... | 2005 | 15839420 |
| infection and activation of bursal macrophages by virulent infectious bursal disease virus. | in this study the effect of infectious bursal disease virus (ibdv) on bursal macrophages during the acute phase of the infection was examined. specific-pathogen-free (spf) chickens were exposed to virulent ibdv and bursal adherent cells were examined by immunohistochemisrty and rt-pcr for virus infection and by real-time quantitative rt-pcr (qrt-pcr) for mrna transcripts of proinflammatory cytokines and inos. viral genome was detected in bursal macrophages at 3, 5 and 7 days post-infection (dpi) ... | 2005 | 15893401 |
| real-time rt-pcr differentiation and quantitation of infectious bursal disease virus strains using dual-labeled fluorescent probes. | a real-time rt-pcr assay was developed utilizing dual-labeled fluorescent probes binding to vp4 sequence that are specific to the classical (cl), variant (v) and very virulent (vv) strains of infectious bursal disease virus (ibdv). the assay was highly sensitive and could detect as little as 3 x 10(2) to 3 x 10(3) copies of viral template. viral genomic copy number could be accurately assayed over a broad range of 7-8 logs of viral genome. the variant sequence-specific probe was found to be high ... | 2005 | 15893570 |
| differences in the immunopathogenesis of infectious bursal disease virus (ibdv) following in ovo and post-hatch vaccination of chickens. | not much is known about ibdv-pathogenesis and immune mechanisms following in ovo vaccination. in this study, we compared the immunopathogenesis of an intermediate ibdv-vaccine in post-hatch- and in ovo-inoculated chickens. in ovo-vaccinated birds recovered significantly faster from lesions of the bursa of fabricius than post-hatch vaccinated (p<0.05). a significant accumulation of intrabursal cd8(+) t cells was observed in post-hatch but not in in ovo-vaccinated chickens (p<0.05). the innate imm ... | 2005 | 15911001 |
| molecular characterization of infectious bursal disease virus isolates from nepal based on hypervariable region of vp2 gene. | two infectious bursal disease virus (ibdv) isolates, np1ssh and np2k were obtained from a severe infectious bursal disease (ibd) outbreak in nepal in 2002. the hypervariable (hv) region of vp2 gene (1326 bp) of the isolates was generated by rt-pcr and sequenced. the obtained nucleotide sequences were compared with those of twenty other ibdv isolates/strains. phylogenetic analysis based on this comparison revealed that np1ssh and np2k clustered with very virulent (vv) ibdv strains of serotype 1. ... | 2005 | 15929400 |
| vaccine and adjuvant activity of recombinant subunit b of e. coli enterotoxin produced in yeast. | escherichia coli heat-labile enterotoxin (lt) and cholera toxin (ct) have been studied intensively as vaccines against diseases caused by those bacteria and as adjuvants for mucosal vaccination. two major problems interfere with the use of these promising adjuvants: their toxicity and the residual bacterial endotoxins mixed with the desired lt. in this study, subunit b of lt was expressed in pichia pastoris yeast cells (yrltb) and the recombinant protein was purified and concentrated by ion-exch ... | 2005 | 15951067 |
| oesophageal tonsil of the chicken. | the oesophageal tonsil of the chicken is a novel member of the mucosal-associated lymphoid tissue (malt), which is located around the entrance of the proventriculus. it consists of 6 to 8 single units, which are surrounded by a thin fibrous capsule. each one is organised around the bottom of the longitudinal folds of the oesophagus, and serves as a 'tonsillar crypt'. stratified squamous epithelium is infiltrated by lymphoid cells, i.e. t cells, plasma cells, macrophages, and dendritic cells, but ... | 2005 | 15959976 |
| dna immunization against very virulent infectious bursal disease virus with vp2-4-3 gene and chicken il-6 gene. | the present study was to investigate the feasibility and efficiency of the dna vaccine to protect chickens against very virulent infectious bursal disease virus (vvibdv) infection. a plasmid dna carrying vp2-4-3 genes of vvibdv sh95 and a plasmid dna carrying chicken interleukin-6 (chil-6) genes were constructed and designated as palter-max-vp2-4-3 and palter-max-chil-6 respectively. several dna vaccination experiments were performed: 1-week-old chickens were intramuscularly injected with only p ... | 2005 | 15702994 |
| effects of dietary ratio of linoleic to linolenic acid on performance, antibody production, and in vitro lymphocyte proliferation in two strains of leghorn pullet chicks. | the effects of dietary ratio of linoleic acid to linolenic acid on performance, mitogenic lymphocyte proliferation, and antibody production were evaluated in leghorn pullets during a rigorous vaccination program. diets were supplemented with flaxseed and corn oil to achieve 4 dietary ratios of linoleic acid to linolenic acid [17:1 (control), 8:1, 4:1, or 2:1]. each diet was fed to hyline brown or w-36 pullets from 1 d to 16 wk of age. day-old pullets were randomly assigned to 8 replicate cages w ... | 2005 | 15971520 |
| secreted expression of the vp2 protein of very virulent infectious bursal disease virus in the methylotrophic yeast pichia pastoris. | the vp2-encoding gene of very virulent infectious bursal disease virus (vvibdv) was amplified using reverse transcription (rt)-polymerase chain reaction (pcr) and inserted into ppiczalphaa vector. recombinant plasmid dna was integrated into the chromosome of the transformed pichia pastoris by electroporation and expressed protein identified by sds-page and western blotting. high-level secreted expression was performed by determining the mut+ phenotype and secreting multi-copy integrants in the r ... | 2005 | 15620405 |
| structure of birnavirus-like particles determined by combined electron cryomicroscopy and x-ray crystallography. | birnaviruses possess a capsid with a single protein layer in contrast to most double-stranded rna viruses infecting multicellular eukaryotes. using freeze-drying and heavy metal shadowing, the capsids of two birnaviruses, infectious bursal disease virus (ibdv) and infectious pancreatic necrosis virus, as well as of an ibdv virus-like particle (vlp) are shown to follow the same t=13 laevo icosahedral geometry. the structure of the vlp was determined at a resolution of approximately 15 a (1.5 nm) ... | 2005 | 16033982 |
| purification of capsid-like particles of infectious bursal disease virus (ibdv) vp2 expressed in e. coli with a metal-ion affinity membrane system. | protein vp2, matured from the polyprotein encoded by the genome of infectious bursal disease virus (ibdv) and the primary host-protective immunogen of this virus, together with its two n-terminal truncated mutants were cloned and expressed in escherichia coli. to obtain pure recombinant proteins for the development of an efficient subunit vaccine against ibdv infection, these three proteins were fused with six additional histidine residues at their c-termini as a his-purification-tag. following ... | 2005 | 16040134 |
| infectious bursal disease virus recovery from vero cells transfected with rna transcripts is enhanced by expression of the structural proteins in trans. | positive sense rna transcripts of infectious bursal disease (ibd) virus genome segments a and b have previously been shown to be infectious. in this study we demonstrate that recovery of ibd virus from the transfection of vero cells with positive sense rna transcripts of genome segments a and b was enhanced by expression of the viral structural proteins vp2 with vp3 or by expression of viral polyprotein vp243 from dna plasmids in trans. expression of individual viral proteins vp2, vp3, or vp4 al ... | 2005 | 16086099 |
| development of a one-step strip test for the diagnosis of chicken infectious bursal disease. | a rapid diagnostic strip for chicken infectious bursal disease (ibd) was developed based on membrane chromatography using high-affinity monoclonal antibodies directed to chicken infectious bursal disease virus (ibdv). the diagnostic strip has high specificity for detection of chicken ibdv antigen and recognizes a variety of the virus isolates, including virulent and attenuated strains, with no cross-reactivity to other viruses, such as newcastle disease virus, marek's disease virus, infectious b ... | 2005 | 16094819 |
| molecular epidemiology of infectious bursal disease viruses: distribution and genetic analysis of newly emerging viruses in the united states. | genetic mutations in the genome of infectious bursal disease virus (ibdv) have resulted in antigenic and pathogenic variants that continue to cause disease in commercially reared chickens. the extent of the genetic diversity among ibdv strains circulating in the united states is unknown. this study was designed to identify newly emerging viruses infecting chickens on poultry farms experiencing immune suppression-related problems. fifty ibdv-positive samples were identified from 273 bursa samples ... | 2005 | 16094826 |
| protective efficacy of intermediate and intermediate plus infectious bursal disease virus (ibdv) vaccines against very virulent ibdv in commercial broilers. | the evolution of very virulent (vv) infectious bursal disease virus (ibdv) has led to significant economic losses in many poultry-producing areas. despite vigorous vaccination strategies, ibdv has been difficult to control. the protective efficacy of ibdv vaccines is traditionally evaluated in specific pathogen-free (spf) chickens. but under field conditions, residual maternal antibody (mab) levels may interfere with vaccine efficacy. in this study, commercial broilers with various levels of mat ... | 2005 | 16094828 |
| molecular studies on suspect very virulent infectious bursal disease virus genomic rna samples. | infectious bursal disease (ibd) associated with high mortality was first observed in europe in the mid-1980s. the viruses identified in those outbreaks were described as being very virulent infectious bursal disease virus (vvibdv) strains. these viruses have spread to nearly every continent but have not yet been identified in north america, australia, and new zealand. there is a real and immediate concern that the very virulent form of ibdv will continue to spread until it is present on every co ... | 2005 | 16094830 |
| health evaluation of free-ranging and captive blue-fronted amazon parrots (amazona aestiva) in the gran chaco, bolivia. | bolivia has a total of 47 species of psittacidae, seven of which have been identified in our study site, the semiarid gran chaco of the isoso. one species, the blue-fronted parrot (amazona aestiva), is frequently captured by local isoseño guaraní indians for exploitation on the national and international market. these birds are often temporarily housed in small villages under unhygienic conditions with poultry and other domestic species. on occasion, these parrots escape back to the wild. additi ... | 2005 | 17312715 |
| transcriptional profiling reveals a possible role for the timing of the inflammatory response in determining susceptibility to a viral infection. | using a novel cdna microarray prepared from sources of actively responding immune system cells, we have investigated the changes in gene expression in the target tissue during the early stages of infection of neonatal chickens with infectious bursal disease virus. infections of two lines of chickens previously documented as genetically resistant and sensitive to infection were compared in order to ascertain early differences in the response to infection that might provide clues to the mechanism ... | 2006 | 16940532 |
| cloning and nucleotide analysis of the vp2 gene of a very virulent infectious bursal disease virus isolate from iran. | an iranian field isolate (ir01) of infectious bursal disease virus (ibdv) was characterized by sequence analysis of its vp2 gene and protein. comparison of the obtained sequences with those of ibdv isolates from other countries revealed that ir01 was similar to very virulent ibdv (vvibdv) strains with the identities at nucleotide and amino acid levels reaching 98.198.9% and 99.199.3%, respectively. on the other hand, it was less similar to non-vvibdv strains; with nucleotide and amino acid ident ... | 2006 | 17177607 |
| identification of infectious bursal disease viruses from rna extracted from paraffin-embedded tissue. | after histopathologic screening of bursas of fabricius for the presence of infectious bursal disease virus (ibdv) lesions, the hypervariable region of the vp2 gene for ibdv was extracted from formalin-fixed paraffin-embedded tissue blocks. with real-time reverse transcription-polymerase chain reaction (rt-pcr) and sequencing, ibdv was identified in 227 different blocks. the ability to identify the actual virus strain associated with the lesions observed microscopically in the bursa of fabricius ... | 2006 | 17274281 |
| molecular characteristics of infectious bursal disease viruses from asymptomatic broiler flocks in europe. | infectious bursal disease virus (ibdv) exists in several different antigenic and pathogenic forms. the immune suppression caused by this virus in young chickens is not always associated with clinical signs of disease. the antigenic variant viruses originally described in the united states typically do not cause clinical signs of disease but can cause a marked immune suppression via the destruction of b lymphocytes. using a reverse transcription-polymerase chain reaction (rt-pcr) assay we conduct ... | 2006 | 17274290 |
| restriction fragment length polymorphism typing of infectious bursal disease virus field strains in turkey. | infectious bursal disease (ibd), also known as gumboro disease, is a highly contagious, immunosuppressive disease of immature chickens. it is caused by ibd virus (ibdv) and is responsible for major economic losses in the poultry industry worldwide. in this study, 280 bursa samples from 56 commercially reared chicken flocks in turkey with clinical symptoms of ibd were examined for ibdvs using the reverse transcription (rt)-polymerase chain reaction (pcr)/restriction fragment length polymorphism ( ... | 2006 | 17274292 |
| inclusion body hepatitis as a primary disease in broilers in saskatchewan, canada. | in recent years inclusion body hepatitis (ibh) has emerged as an economically important disease in western canada. historically, infections with infectious bursal disease virus (ibdv) and chicken anemia virus (cav) have been known to suppress the immune system of broilers and make them more susceptible to a secondary disease such as ibh. recently it has been reported that virulent adenoviruses are able to cause ibh as a primary disease in broilers without apparent involvement of ibdv and cav. th ... | 2006 | 17274293 |
| a practical tissue sampling method using ordinary paper for molecular detection of infectious bursal disease virus rna by rt-pcr. | a practical sampling method for bursal tissue using ordinary paper for molecular diagnosis of infectious bursal disease (ibd) was established. ibd virus-infected bursa was directly smeared on chromatography paper, filter paper, or stationery copy paper and was then fixed with absolute ethanol, tris-hcl-saturated phenol, or phenol:chloroform:isoamyl alcohol (25:24:1). flinders technology associates (fta) card, which is designed for the collection of biological samples for molecular detection, was ... | 2006 | 17274294 |
| detection of very virulent strains of infectious bursal disease virus (vvibdv) in commercial broilers from uruguay. | bursal samples were collected from commercial broiler flocks exhibiting clinical signs suggestive of infectious bursal disease (ibd). the presence of ibd virus (ibdv) was confirmed by partial amplification of the vp2 and vp1 genes by reverse transcription and polymerase chain reaction. the uruguayan viruses were identified as very virulent strains of ibdv (vvibdv) by nucleotide and amino acid sequence analysis. the comparison of the vp2 nucleotide sequences among the uruguayan samples revealed t ... | 2006 | 17274305 |
| molecular characterization of indian isolates of infectious bursal disease virus from broiler chickens. | the present study was undertaken to characterize recent field isolates of infectious bursal disease virus (ibdv) by reverse transcription-polymerase chain reaction (rt-pcr) and partial sequencing of vp2 gene. the virus could be detected in 17 of 20 field samples from broiler chickens in haryana state, india as well as in all the four vaccine strains. nucleotide sequences of four field isolates and one vaccine strain were compared with 10 reported ibdv strains from different parts of the world. n ... | 2006 | 17381044 |
| oral administration of hyperimmune igy: an immunoecological approach to curbing acute infectious bursal disease virus infection. | infectious bursal disease (ibd) is one of the most important viral diseases of poultry. hygienic management and proper vaccination are currently the only economic approach for control of this disease. attempts have been made to control the disease after the onset of an outbreak using parenteral administration of hyperimmune igy preparations. such attempts are usually cumbersome and time consuming with an overall reduced economic return. we investigated the use of oral administration of hyperimmu ... | 2006 | 18689274 |
| molecular epidemiology of chicken anemia virus in nigeria. | between february 2002 and may 2004, chicken anemia virus (cav) was detected by pcr in organ samples from 14 flocks of poultry farms in lagos, ogun and oyo states in southwestern nigeria. the farms reported low (<5%) to high mortalities (up to 100%) with various lesions at necropsy. the complete vp1 gene of 30 of these positive strains was sequenced. strains that diverged by up to 4.4% on a nucleotide level differed only by up to 2.5% at the amino acid level (7 aa) as a result of clustered silent ... | 2006 | 16096706 |
| differential detection of turkey coronavirus, infectious bronchitis virus, and bovine coronavirus by a multiplex polymerase chain reaction. | the objective of the present study was to develop a multiplex polymerase chain reaction (pcr) method for differential detection of turkey coronavirus (tcov), infectious bronchitis coronavirus (ibv), and bovine coronavirus (bcov). primers were designed from conserved or variable regions of nucleocapsid (n) or spike (s) protein gene among tcov, ibv, and bcov and used in the same pcr reaction. reverse transcription followed by the pcr reaction was used to amplify a portion of n or s gene of the cor ... | 2006 | 16137773 |
| passive immunization using purified igys against infectious bursal disease of chickens in pakistan. | infectious bursal disease (ibd) is an acute and highly contagious disease of young chickens caused by birnavirus. mortality of infected birds can be best prevented if injected with antibodies. the present study was an attempt to raise specific hyper-immune polyclonal antibodies against ibd virus in pakistan. commercial layers divided into four groups were injected with ibd vaccine subcutaneously according to four different treatment regimens. eggs were collected daily and antibodies were purifie ... | 2006 | 16434848 |
| preparation and evaluation of vero-cell infectious bursal disease vaccine in pakistan. | the present work was carried out to develop an effective vaccine to control infectious bursal disease (ibd). the very virulent infectious bursal disease virus (vvibdv) was adapted to grow in vero-cell line after three serial passages. the virus was then attenuated by further serial passages and pathogenicity of different passages was determined in broiler chicks free from antibodies against ibdv. the ninth passage virus was completely attenuated, as it was non-pathogenic to chicks. the birds ino ... | 2006 | 16490290 |
| chicken recombinant antibodies specific for very virulent infectious bursal disease virus. | a phage-displayed single chain variable fragment (scfv) antibody library was constructed from the immune spleen cells of chickens immunized with very virulent infectious bursal disease virus (vvibdv) strain cs89. a library consisting of around 9.2 x 10(7) clones was subjected to 3 rounds of panning against captured cs89 virus. analysis of individual clones by nucleotide sequencing revealed at least 22 unique scfv antibodies binding to vvibdv in elisa. testing of the scfv antibody panel in elisa ... | 2006 | 16514499 |
| inactivation of infectious bursal disease virus by binary ethylenimine and formalin. | in this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (ibdv) by binary ethylenimine (bei) in comparison with formalin, ibdv was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. viral suspensions were subjected to inactivation with bei and formalin for pre-set time intervals. bei was employed at concentrations of 0.001 and 0.002 mol/l while formalin was used at 0.1% and 0.2%. sampling was done a ... | 2006 | 16532536 |
| association of twelve immune-related genes with performance of three broiler lines in two different hygiene environments. | elite populations of farm animals under genetic selection are often maintained in high hygiene conditions, yet the commercial populations may be raised in, and are expected to perform well in, environments of varied hygiene levels. this presents special challenges to genetically improve those traits for which genotype by environment interactions are important. twelve immune-related genes were studied for associations with general mortality and other performance traits in 3 elite commercial broil ... | 2006 | 16977841 |
| evaluation of fta paper and phenol for storage, extraction and molecular characterization of infectious bursal disease virus. | infectious bursal disease virus (ibdv) is an important poultry pathogen and is distributed world wide that can cause immune suppression and lesions of the bursa of fabricius. the main component of the virus, vp2, is not only responsible for the bird's immune response, but is important for the molecular identification of this virus as well. the nucleic acid of the virus must be adequately preserved to be analyzed by reverse-transcriptase pcr (rt-pcr) and sequenced for the molecular characterizati ... | 2006 | 16978712 |
| impact of coccidial infection on vaccine- and vvibdv in lymphoid tissues of spf chickens as detected by rt-pcr. | this study aimed at investigating a potential effect caused by coccidia on the immune response to vaccine- and very virulent infectious bursal disease virus (vvibdv) in spf chickens. | 2006 | 16987396 |
| genetic reassortment of infectious bursal disease virus in nature. | infectious bursal disease virus (ibdv), a double-stranded rna virus, is a member of the birnaviridae family. four pathotypes of ibdv, attenuated, virulent, antigenic variant, and very virulent (vvibdv), have been identified. we isolated and characterized the genomic reassortant ibdv strain zj2000 from severe field outbreaks in commercial flocks. full-length genomic sequence analysis showed that zj2000 is a natural genetic reassortant virus with segments a and b derived from attenuated and very v ... | 2006 | 17010936 |
| altered circulating levels of serotonin and immunological changes in laying hens divergently selected for feather pecking behavior. | the aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (fp) behavior [high fp (hp) line and low fp (lp) line] for 5 generations. the hens from the hp line had a higher plasma serotonin level than those from the lp line (0.059 vs. 0.037 micromol/l, f(2,27) = 0.031, p < 0.05). the plasma level of tryptophan was, on average, 67.30 micromol/l and di ... | 2006 | 17012161 |
| effects of chicken intestinal antimicrobial peptides on humoral immunity of chickens and antibody titres after vaccination with infectious bursal disease virus vaccine in chicken. | sixty chickens were randomly divided into two groups (30 chickens in each group) to determine the effect of oral administration of chicken intestinal antimicrobial peptides (ciamp) on the humoral immune response. chickens of both groups were fed the same diet. in the treatment group chickens received drinking water supplemented with ciamp (1 microg/ml) right after hatching. samples of blood, bursa of fabricus, spleen and intestine were taken at day 1, 4, 7, 10 and 17 of experiment. ciamp supplem ... | 2006 | 17036752 |
| molecular analysis of infectious bursal disease virus from bursal tissues collected on fta filter paper. | we investigated the feasibility of using fta filter cards for the storage of bursas of fabricius containing infectious bursal disease virus (ibdv) and for ibdv detection by reverse transcriptase (rt)-polymerase chain reaction (pcr), and characterization by restriction fragment length polymorphism (rflp) or nucleotide sequencing. the fta card is a cotton-based cellulose membrane containing lyophilized chemicals that lyses many types of bacteria and viruses. ibdv was inactivated upon contact with ... | 2006 | 17039839 |
| the effect of co-administration of dna carrying chicken interferon-gamma gene on protection of chickens against infectious bursal disease by dna-mediated vaccination. | the purpose of the present study was to determine whether dna vaccination by co-administration of dna coding for chicken interferon-gamma (ifn-gamma) gene and dna encoding for the vp243 gene of ibdv could enhance immune response and protection efficacy of chickens against challenge by ibdv. plasmids carrying vp243 gene of ibdv strain variant e (ve) (p/vp243/e) and chicken ifn-gamma gene (p/cifn-gamma) were constructed, respectively. one-day-old chickens were intramuscularly injected with p/vp243 ... | 2006 | 17050043 |
| hematology, serum chemistry, and serology of galápagos penguins (spheniscus mendiculus) in the galápagos islands, ecuador. | the galápagos penguin (spheniscus mendiculus) is an endangered species endemic to the galápagos islands, ecuador. in 2003 and 2004, 195 penguins from 13 colonies on the islands of isabela and fernandina in the galápagos archipelago were examined. genetic sexing of 157 penguins revealed 62 females and 95 males. hematology consisted of packed cell volume (n = 134), white blood cell differentials (n = 83), and hemoparasite blood smear evaluation (n = 114). microfilariae were detected in 22% (25/114 ... | 2006 | 17092893 |
| effects of dda, cpg-odn, and plasmid-encoded chicken ifn-gamma on protective immunity by a dna vaccine against ibdv in chickens. | this study examined the adjuvant effects of dimethyl dioctadecyl ammonium bromide (dda), cpg oligodeoxynucleotides (cpg-odn), and chicken interferon-gamma (chifn-gamma) on a dna vaccine (pcdna-vp243) against the infectious bursal disease virus (ibdv). a plasmid encoding chicken ifn-ã was constructed. twice at 2-week intervals, two-week-old chickens were injected intramuscularly and intraperitoneally with either a dna vaccine alone or a dna vaccine together with the respective adjuvants. on week ... | 2006 | 17106228 |
| epidemiological and experimental evidence for immunodeficiency affecting avian infectious bronchitis. | we evaluated the effects of viral immunodeficiency on the outcome of infectious bronchitis virus (ibv) infection in chickens as a hypothetical cause for failure of adequate protection in vaccinated chickens. initially, we investigated ibv isolations from cases of respiratory disease in association with the presence of thymic and/or bursal atrophy in 322 submissions during 1997 to 2002. arkansas (ark)-type ibv was most frequently isolated in spite of extensive arkdpi vaccination in the broiler in ... | 2006 | 17121734 |
| in vitro expression and monoclonal antibody of rna-dependent rna polymerase for infectious bursal disease virus. | vp1, the rna-dependent rna polymerase of infectious bursal disease virus (ibdv), has been suggested to play an essential role in the replication and translation of viral rnas. in this study, we first expressed the complete vp1 protein gene in escherichia coli (e. coli), and then the produced polyclonal antibody and four monoclonal antibodies (mabs) to recombinant vp1 protein (rvp1) were shown to bind the ibdv particles in chicken embryo fibroblast and vero cells. the epitopic analysis showed tha ... | 2006 | 17132096 |
| diseases of indigenous chickens in bokaa village, kgatleng district, botswana. | this study examined flock size and management, level of internal and external parasite burden and seroprevalence of antibodies to poultry pathogens in indigenous chickens in bokaa village, kgatleng district, botswana. the mean flock size was 22.6 +/- 6.85 with a range of 11-34. the mean body weights of cocks and hens were 2.28 +/- 0.56 kg and 1.70 +/- 0.38 kg, respectively. housing and commercial poultry feed were not provided. ascaridia galli, heterakis gallinarum and syngamus trachea were foun ... | 2006 | 17137053 |
| b subunit of e. coli enterotoxin as adjuvant and carrier in oral and skin vaccination. | mucosal sites are one of the main natural ports of entry into the body. stimulation of a local response by antibodies as the systemic protection may enhance the efficacy of non-living vaccines, and allow for vaccination by subunit vaccines without the need for injection. mucosal or skin vaccination necessitates a suitable adjuvant and carrier. escherichia coli heat-labile enterotoxin (lt) and its b subunit (ltb) have been found to be effective adjuvants. the aim of this study was to efficiently ... | 2006 | 16701905 |
| purification of vp3 protein of infectious bursal disease virus using nickel ion-immobilized regenerated cellulose-based membranes. | in this study, hexa-histidine tagged vp3 protein of infectious bursal disease virus (ibdv) was purified using immobilized metal ion affinity technique from the fermentation of escherichia coli bl21 (de3) containing a recombinant plasmid with a vp3 gene. the purification efficiencies of vp3 protein (tvp3 and deltatvp3) using ni(2+)-nta commercial agarose gels and ni(2+)-ida regenerated cellulose-based membranes at 4 degrees c were compared. a good washing condition for removing most impurity prot ... | 2006 | 16716768 |
| l-arginine stimulates intestinal intraepithelial lymphocyte functions and immune response in chickens orally immunized with live intermediate plus strain of infectious bursal disease vaccine. | infectious bursal disease (ibd) continues to pose potential threat to poultry industry all over the world. the disease can spell disaster not only through its infection but also by break of immunity in chickens vaccinated for other diseases. l-arginine, a ubiquitous, semi-essential amino acid has emerged as an imunostimulant from variety of human and animal studies. in the present study, we demonstrate the stimulatory effects of l-arginine on intestinal intraepithelial lymphocyte (iiels) functio ... | 2006 | 16723175 |
| processing of infectious bursal disease virus (ibdv) polyprotein and self-assembly of ibdv-like particles in hi-5 cells. | the capsid of infectious bursal disease virus (ibdv), with a size of 60-65 nm, is formed by an initial processing of polyprotein (pvp2-vp4-vp3) by vp4, subsequent assemblage of pvp2 and vp3, and the maturation of vp2. in sf9 cells, the processing of polyprotein expressed was restrained in the stage of vp2 maturation, leading to a limited production of capsid, i.e., ibdv-like particles (vlps). in the present study, another insect cell line, high-five (hi-5) cells, was demonstrated to efficiently ... | 2006 | 16739960 |
| phylogenetic diversity of avian nephritis virus in hungarian chicken flocks. | avian nephritis virus (anv) infection was detected in 4-day-old to 22-day-old chickens collected on hungarian farms between 2002 and 2005. the animals suffered from diarrhoea, growth retardation, runting-stunting syndrome, and 2 to 6% mortality was reported. tubulonephrosis, interstitial nephritis and uricosis (gout) was diagnosed. the presence of anv rna was detected in chicken carcasses using reverse transcriptase-polymerase chain reaction. the virus was demonstrated in 69% of the investigated ... | 2006 | 16753614 |
| reciprocal antibody and complement responses of two chicken breeds to vaccine strains of newcastle disease virus, infectious bursal disease virus and infectious bronchitis virus. | serum antibody responses and haemolytic complement activity were evaluated in white leghorn (wlh) and rhode island red (rir) chickens that were vaccinated with live-attenuated vaccines of newcastle disease virus, or infectious bronchitis virus, or infectious bursal disease virus by means of ocular challenge at 10 times the normal vaccination dose. complement titres in non-vaccinated birds were significantly higher in wlh birds compared to rir birds. the lentogenic viral infection resulted in an ... | 2006 | 16755366 |
| [construction and immunological characterization of recombinant marek's disease virus expressing ibdv vp2 fusion protein]. | a transfer plasmid vector puc18-us10-vp2 was first constructed by inserting the gene of the enhancer green fluorescent protein(egfp) fused to the vp2 gene of very virulent infectious bursal disease virus (ibdv) js strain into the us10 fragment of the marek's disease virus (mdv) cv1988/rispens. the recombinant virus, designated as rmdv, was developed by co-transfecting cef with the transfer plasmid vector and simultaneously infecting with the cvi988/rispens virus. the pcr and ifa results indicate ... | 2006 | 16755916 |
| oral dna vaccination with the polyprotein gene of infectious bursal disease virus (ibdv) delivered by the attenuated salmonella elicits protective immune responses in chickens. | our previous study showed that vaccination with plasmid dna containing infectious bursal disease virus (ibdv) gene which encodes complete polyprotein (vp2/4/3) induced protective immune responses. in this study, we examined the efficacy of an oral dna vaccine carrying the ibdv polyprotein antigen delivered by attenuated salmonella enterica sv. typhimurium (s. typhimurium). the recombinant plasmid pci-vp2/4/3 was transformed by electroporation into an attenuated s.typhimurium strain (dam phop) (d ... | 2006 | 16769159 |
| immune response to a killed infectious bursal disease virus vaccine in inbred chicken lines with different major histocompatibility complex haplotypes. | the influence of mhc on antibody responses to killed infectious bursal disease virus (ibdv) vaccine was investigated in several mhc inbred chicken lines. we found a notable mhc haplotype effect on the specific antibody response against ibdv as measured by elisa. some mhc haplotypes were high responders (b201, b4, and br5), whereas other mhc haplotypes were low responders (b19, b12 and bw3). the humoral response of 1 pair of recombinants isolated from a red jungle fowl (bw3 and bw4) being identic ... | 2006 | 16776466 |
| calculation of spherical harmonics and wigner d functions by fft. applications to fast rotational matching in molecular replacement and implementation into amore. | the fft calculation of spherical harmonics, wigner d matrices and rotation function has been extended to all angular variables in the amore molecular replacement software. the resulting code avoids singularity issues arising from recursive formulas, performs faster and produces results with at least the same accuracy as the original code. the new code aims at permitting accurate and more rapid computations at high angular resolution of the rotation function of large particles. test calculations ... | 2006 | 16788266 |
| the 2.6-angstrom structure of infectious bursal disease virus-derived t=1 particles reveals new stabilizing elements of the virus capsid. | infectious bursal disease virus (ibdv), a member of the birnaviridae family, is a double-stranded rna virus that causes a highly contagious disease in young chickens leading to significant economic losses in the poultry industry. the vp2 protein, the only structural component of the ibdv icosahedral capsid, spontaneously assembles into t=1 subviral particles (svp) when individually expressed as a chimeric gene. we have determined the crystal structure of the t=1 svp to 2.60 a resolution. our res ... | 2006 | 16809295 |
| in vivo activation of chicken macrophages by infectious bursal disease virus. | infectious bursal disease virus (ibdv) infects and replicates in the dividing b lymphocytes of chickens. in the present study, the in vivo effect of ibdv infection on chicken macrophage populations and macrophage activation were examined. specific-pathogen-free chickens were exposed to virulent ibdv and splenic macrophages were recovered during the acute phase of the disease. at 3 and 5 days post-infection (dpi), spleens of virus-exposed chickens had fewer macrophages than those of virus-free co ... | 2006 | 16817773 |
| effects of two infectious bursal disease vaccine virus strains on hepatic microsomal enzyme activities in chickens. | the influence of two infectious bursal disease vaccines on the activities of hepatic microsomal enzymes aniline hydroxylase, ethylmorphine n-demethylase, nadph-cytochrome c reductase, aryl sulphotransferase and p-nitrophenol udp-glucuronyltransferase was investigated in chickens. the vaccines contained attenuated winterfield 2512 and vmg-91 strains, respectively. the activities of enzymes were determined on postvaccination days 0, 2, 5 and 7. at the same time, post-mitochondrial supernatant, cyt ... | 2006 | 16841765 |
| immunogenicity of formaldehyde and binary ethylenimine inactivated infectious bursal disease virus in broiler chicks. | infectious bursal disease virus (ibdv) was inactivated by two different chemicals--formaldehyde and binary ethylenimine (bei). formaldehyde was used at 0.1% and 0.2%, while bei was used at concentrations of 0.001 and 0.002 mol/l. these four vaccines were tested for their efficiency in generating humoral immune response in different groups of broiler chicks. both bei-inactivated vaccines gave relatively higher antibody titers and were almost twice as efficient as formaldehyde-inactivated ones. | 2006 | 16845721 |
| chicken recombinant antibodies against infectious bursal disease virus are able to form antibody-virus immune complex. | virus particles exposed to specific anti-virus antibodies result in the formation of immune complexes (icx). recent vaccination strategies have employed this feature, and an infectious bursal disease virus (ibdv) vaccine based on icx has been released and is expected to replace conventional ibdv vaccines. we evaluated whether chicken recombinant antibodies (rab) specific for ibdv, rather than conventional chicken anti-ibdv sera, could be used to generate icx. out of 14 rab expressed as soluble s ... | 2006 | 16854642 |
| the anti-nuclease humoral immune response of broiler chickens exposed to staphylococcus aureus, infectious bursal disease virus and chicken anaemia virus in an experimental model for bacterial chondronecrosis and osteomyelitis. | this study aimed to develop an enzyme-linked immunosorbent assay to detect antibody associated with staphylococcus aureus that is produced during the chicken immune response to this organism. the protein nuclease was tested for suitability as an antigen to detect antibody in sera from broiler chickens that had been exposed to aerosolized s. aureus on day 1 post hatch during experiments to reproduce bacterial chondronecrosis and osteomyelitis. an enzyme-linked immunosorbent assay was developed to ... | 2006 | 16854643 |
| impact of heterophil granulocyte depletion caused by 5-fluorouracil on infectious bursal disease virus infection in specific pathogen free chickens. | the purpose of this study was to investigate the influence of the cytostatic drug, 5-fluorouracil (5-fu), which causes depletion of heterophil granulocytes, on clinical symptoms and histological lesions during the progress of infectious bursal disease virus (ibdv) infection in chickens. the aim was to disclose the mechanism behind the clinical disease symptoms. three groups of specific pathogen free chickens were used for the experiment. chickens in groups 1 and 3 were pretreated with 5-fu, whil ... | 2006 | 16854650 |
| infectious bursal disease virus-induced immunosuppression exacerbates campylobacter jejuni colonization and shedding in chickens. | campylobacter jejuni is the leading cause of food-borne bacterial gastroenteritis in humans in the united states. infectious bursal disease virus (ibdv) causes an immunosuppressive disease in young chickens. to analyze a possible role of ibdv-induced immunosuppression in colonization and shedding of c. jejuni, two experiments were conducted. in both experiments, group 1 consisted of noninoculated control chickens, groups 2 and 3 were inoculated with varying doses of c. jejuni, and groups 4 and 5 ... | 2006 | 16863064 |
| reduced serologic response to newcastle disease virus in broiler chickens exposed to a chinese field strain of subgroup j avian leukosis virus. | in this study, a chinese field strain of subgroup j avian leukosis virus (alv-j), nx0101, was studied for its immunosuppressive effects in both commercial broilers and spf white leghorn chickens infected at 1 day of age. our data demonstrated that nx0101 induced much more significant body and immune organ weight loss in the infected commercial broiler chickens in an earlier age than that in the spf white leghorn chickens. at the same time antibody responses to vaccinations of newcastle disease v ... | 2006 | 16863066 |
| characterization of infectious bursal disease viruses from argentina. | infectious bursal disease (ibd) viruses detected in commercial flocks of different regions of argentina were analyzed by reverse transcription-polymerase chain reaction-restriction fragment length polymorphism (rflp) of a vp2 gene fragment, followed by sequence analysis. two out of eight ibd viruses presented an sspi restriction site, typical of the very virulent phenotype. three ibd viruses presented a saci restriction site, typical of classic virulent strains, and one isolate presented restric ... | 2006 | 16863075 |
| effect of infectious bursal disease virus insult on iron, copper, and zinc concentration in liver, bursa of fabricius, spleen, pancreas, and serum of chickens. | the effect of a systemic disease on the dynamics of iron, zinc, and copper in chickens fed ad libitum was examined by infecting 10-day-old specific pathogen-free chickens with infectious bursal disease virus (ibdv). liver, bursa of fabricius, pancreas, spleen, and serum were sampled in 10 controls and 10 challenged chickens at 3-day intervals postinfection (pi) for 15 days. the samples were analyzed using atomic absorption spectroscopy. serum levels were similar to that reported in the literatur ... | 2006 | 16863087 |
| efficacy of vp2 protein expressed in e. coli for protection against highly virulent infectious bursal disease virus. | the ability of a heat-inactivated whole virus from a highly virulent infectious bursal disease virus (hvibdv) and vp2 protein from hvibdv expressed in e. coli provided protection against a hvibdv challenge in specificpathogen-free (spf) chickens. six out of seven chickens that were injected three times with crude vp2 protein developed significant antibody titer against ibdv. however, only four out of the seven chickens survived the hvibdv challenge. despite showing low antibody titer profiles, a ... | 2006 | 16871018 |
| economically important non-oncogenic immunosuppressive viral diseases of chicken--current status. | immunosuppressive viral diseases threaten the poultry industry by causing heavy mortality and economic loss of production, often as a result of the chickens' increased susceptibility to secondary infections and sub-optimal response to vaccinations. this paper aimed to present an up-to-date review of three specific economically important non-oncogenic immunosuppressive viral diseases of chickens, viz. chicken infectious anaemia (cia), infectious bursal disease (ibd) and hydropericardium syndrome ... | 2006 | 16883664 |
| phylogenetic analysis reveals a correlation between the expansion of very virulent infectious bursal disease virus and reassortment of its genome segment b. | infectious bursal disease virus (ibdv) is a birnavirus causing immunosuppressive disease in chickens. emergence of the very virulent form of ibdv (vvibdv) in the late 1980s dramatically changed the epidemiology of the disease. in this study, we investigated the phylogenetic origins of its genome segments and estimated the time of emergence of their most recent common ancestors. moreover, with recently developed coalescence techniques, we reconstructed the past population dynamics of vvibdv and t ... | 2006 | 16912300 |
| l-arginine stimulates immune response in chickens immunized with intermediate plus strain of infectious bursal disease vaccine. | infectious bursal disease continues to pose an important threat to the commercial poultry industry, especially after the emergence of virulent infectious bursal disease virus (ibdv). l-arginine, a ubiquitous, basic amino acid is used as an immunostimulant in variety of human and animal studies with great success in immunosuppressed hosts. in the present study, we evaluated the immunomodulatory effects of l-arginine on humoral and cellular immune response in chickens immunized with live intermedi ... | 2006 | 16168528 |
| nonstructural protein of infectious bursal disease virus inhibits apoptosis at the early stage of virus infection. | infectious bursal disease virus (ibdv), the causative agent of a highly contagious disease in chickens, carries a small nonstructural protein (ns). this protein has been implicated to play a role in the induction of apoptosis. in this study, we investigate the kinetics of viral replication during a single round of viral replication and examine the mechanism of ibdv-induced apoptosis. our results show that it is caspase dependent and activates caspases 3 and 9. nuclear factor kappa b (nf-kappab) ... | 2006 | 16537604 |
| infectious bursal disease virus: strains that differ in virulence differentially modulate the innate immune response to infection in the chicken bursa. | little is understood about the immune responses involved in the pathogenesis of infectious bursal disease virus (ibdv). strains of ibdv differ in their virulence: f52/70 is a classical virulent strain (vibdv), whereas uk661 is a very virulent strain (vvibdv) that causes greater pathology and earlier mortality. the exact causes of clinical disease and death are still unclear. pro-inflammatory cytokines such as interleukin (il)-1beta and il-6, produced by activated macrophages, could play a role, ... | 2006 | 16553553 |
| diversified bursal medullary b cells survive and expand independently after depletion following neonatal infectious bursal disease virus infection. | the primary immunoglobulin repertoire of chickens is generated not by gene rearrangement but by a subsequent process of gene conversion in proliferating immature b cells within the follicles of a specialized gut-associated lymphoid organ, the bursa of fabricius. neonatal infection with infectious bursal disease virus can eliminate almost the entire bursal b-cell compartment. thereafter, two types of follicle reappear. larger follicles, with rapidly proliferating b cells and normal structure, are ... | 2006 | 16556270 |
| crystal structure of a novel viral protease with a serine/lysine catalytic dyad mechanism. | the blotched snakehead virus (bsnv), an aquatic birnavirus, encodes a polyprotein (nh2-pvp2-x-vp4-vp3-cooh) that is processed through the proteolytic activity of its own protease (vp4) to liberate itself and the viral proteins pvp2, x and vp3. the protein pvp2 is further processed by vp4 to give rise to the capsid protein vp2 and four structural peptides. we report here the crystal structure of a vp4 protease from bsnv, which displays a catalytic serine/lysine dyad in its active site. this is th ... | 2006 | 16584747 |
| molecular characterization of recent infectious bursal disease virus isolates from malaysia. | three isolates of infectious bursal disease virus (ibdv), designated upm04178, upm04190 and upm04238, were obtained from severe outbreaks of infectious bursal disease (ibd) in malaysia in 2004. the hypervariable region (hpvr) of vp2 gene of these isolates was sequenced. the obtained sequences were compared with those of other isolates. the highest similarity (98%) concerning both nucleotide and amino acid sequences was found to very virulent ibdv (vvibdv) strains. phylogenetic analysis revealed ... | 2006 | 16599185 |
| protection capability of recombinant plasmid dna vaccine containing vp2 gene of very virulent infectious bursal disease virus in chickens adjuvanted with cpg oligodeoxynucleotide. | in the present study the efficacy of recombinant plasmids dna vaccine encoding vp2 gene of very virulent strain of infectious bursal disease virus (vvibdv) isolated from pakistan was investigated with or without coadministration of cytocine-phosphate-guanine oligodeoxynucleotide (cpg odn) to protect the chickens against the disease. vp2 gene of vvibdv was successfully amplified by reverse transcription-polymerase chain reaction (rt-pcr) and was cloned into eukaryotic expression plasmid vector, w ... | 2006 | 16600440 |
| [inhibitory effect of new antimicrobial substance by bacillus subtilis fmbj on newcastle disease virus and infectious bursal disease virus in vitro]. | the resistance effect on newcastle disease virus (ndv) and infectious bursal disease virus(ibdv) in vitro of a new antimicrobial substance (as), which produced by a bacillus subtilis strain named b. subtilis fmbj. results showed that the td50 and td0 value of this as on chicken embryo fibroblasts cell (cef) were 128.95mg/l and 25.79mg/l, respectively. this as could strongly inhibit the cytopathic effects of cell induced by ndv as well as ibdv, and increase the survival rate of cell remarkably. t ... | 2006 | 16607965 |
| detection of antibodies against serotypes 1 and 2 infectious bursal disease virus by commercial elisa kits. | two distinct serotypes of infectious bursal disease virus (ibdv) are recognized in chicken and turkey flocks in the united states. serologic testing of chicken flocks for serotype 1 viruses is routinely performed to monitor disease status and vaccination. earlier studies indicated that enzyme-linked immunosorbent assay (elisa) test detects antibodies to both serotypes of the virus, while the virus neutralization (vn) test is serotype specific. it is useful to evaluate currently available commerc ... | 2006 | 16617991 |
| in ovo dna immunisation followed by a recombinant fowlpox boost is fully protective to challenge with virulent ibdv. | the aim of this study was to investigate the potential use of dna vaccination delivered in ovo for protecting against challenge with infectious bursal disease virus (ibdv). using a plasmid expressing the beta-galactosidase gene, dna was successfully delivered to the embryo after in ovo injection and localises to the proventriculus and thymus. the coding sequence for the immunogenic ibdv protein, vp2, was cloned into pci-neo, creating pci-vp2. complete protection against ibdv was obtained by prim ... | 2006 | 16621184 |
| application of on-line our measurements to detect actions points to improve baculovirus-insect cell cultures in bioreactors. | the continuous monitoring of a process based on the culture of sf9 insect cells and infection by a baculovirus as a vector to obtain recombinant vp2 protein is studied. on-line our determination is based on the direct oxygen measurement in the cell culture vessel and the application of the dynamic method. this approximation allows a proper description of cell growth, with precise identification of the balanced cell growth end and the most important action times in the process, as virus infection ... | 2006 | 16647779 |
| crystal structure of infectious bursal disease virus vp2 subviral particle at 2.6a resolution: implications in virion assembly and immunogenicity. | the structural protein vp2 of infectious bursal disease virus (ibdv) spontaneously forms a dodecahedral t=1 subviral particle (svp), and is a primary immunogen of the virus. in this study, the structure of ibdv svp was determined in a cubic crystal and refined to 2.6a resolution. it contains 20 independent vp2 subunits in a crystallographic asymmetric unit. each subunit is folded mainly into a shell domain and a protrusion domain, both with the swiss-roll topology, plus a small helical base doma ... | 2006 | 16677827 |
| infectious bursal disease virus infection induces macrophage activation via p38 mapk and nf-kappab pathways. | in the present study, we show that infection with infectious bursal disease virus (ibdv) causes activation of macrophages, the key cells involved in inflammatory and immune-regulatory functions. exposure of cultured spleen macrophages (sm) from spf chickens to ibdv resulted in the production of nitric oxide (no). in addition, there was upregulation of mrna expression of inducible nitric oxide synthase (inos), il-8 and cyclooxygenase-2 (cox-2). the signal transduction pathways involved in macroph ... | 2006 | 16388870 |
| very virulent infectious bursal disease virus: reduced pathogenicity in a rare natural segment-b-reassorted isolate. | the purpose of this study was to compare the molecular epidemiology of infectious bursal disease virus (ibdv) segments a and b of 50 natural or vaccine ibdv strains that were isolated or produced between 1972 and 2002 in 17 countries from four continents, with phenotypes ranging from attenuated to very virulent (vv). these strains were subjected to sequence and phylogenetic analysis based on partial sequences of genome segments a and b. although there is co-evolution of the two genome segments ( ... | 2006 | 16361433 |