Publications

diagnostic procedures after completion of oral immunisation against classical swine fever in wild boar.	the purpose of this paper is to define diagnostic procedures for wild boar after the completion of oral immunisation against classical swine fever (csf). epidemiological analysis of csf in wild boar in germany demonstrated that it is vital to carry out virological investigations on all animals found dead, sick or involved in traffic accidents. in principle, this should ensure an effective and prompt diagnosis of csf. in addition, a defined number of wild boar, especially young animals < or = 6 m ...	2006	17361765
assessment of classical swine fever diagnostics and vaccine performance.	rapid and accurate diagnosis is of the utmost importance in the control of epizootic diseases such as classical swine fever (csf), and efficacious vaccination can be used as a supporting tool. while most of the recently developed csf vaccines and diagnostic kits are mostly validated according to world organisation for animal health (oie) standards, not all of the well-established traditional vaccines and diagnostic tests were subject to these validation procedures and requirements. in this repor ...	2006	17361768
comparative susceptibility of indigenous and improved pig breeds to classical swine fever virus infection: practical and epidemiological implications in a subsistence-based, developing country setting.	this study investigated the comparative susceptibility of indigenous moo laat and improved large white/landrace pig breeds to infection with classical swine fever virus (csfv) under controlled conditions in the lao people's democratic republic (lao pdr). the moo laat (ml) and large white/landrace cross-breed (lwc) pigs were inoculated with a standard challenge strain designated lao/kham225 (infectivity titre of 10(2.75) tcid50/ml). the results demonstrated that both the native breed and an impro ...	2006	17243474
serodiagnostic comparison between two methods, elisa and surface plasmon resonance for the detection of antibodies of classical swine fever.	a protein chip based on surface plasmon resonance (spr) was developed to measure the antibody (ab) titers of classical swine fever virus (csfv) using the recombinant gp55 protein as an antigen. the diagnostic potential of this spr assay for detecting the ab titers to csfv gp55 was compared that of the enzyme-linked immunosorbent assay (elisa) using 170 serum samples from 14 pig farms. the spr assay was highly specific and sensitive, and there were no cross-reactions detected. there was a strong ...	2006	17213702
pasteurella multocida and its role in porcine pneumonia.	pasteurella multocida has been recognized as a contributor to debilitating and fatal porcine pneumonia for at least 120 years and there continues to be sustained, unabated high prevalence of the organism in cases submitted for diagnostic work up. understanding of its role in disease has been limited, in part because of difficulty in reproducing the disease experimentally with capsular type a strains of p. multocida, the predominant type associated with porcine pneumonia. this limitation has stym ...	2006	17389051
characterization of epitopes for neutralizing monoclonal antibodies to classical swine fever virus e2 and erns using phage-displayed random peptide library.	infection of cells with classical swine fever virus (csfv) is mediated by the interaction of envelope glycoproteins e2 and erns with receptor molecules on the cell surface. these proteins are also the major antigens for eliciting neutralizing antibodies and conferring protective immunity. here we report the identification of multiple neutralizing epitopes on these proteins by screening a phage-displayed random peptide library with csfv-specific neutralizing monoclonal antibodies. two different e ...	2006	16132176
detection and quantitative pathogenesis study of classical swine fever virus using a real time rt-pcr assay.	a real time reverse transcription (rt) taqman pcr assay for the detection of classical swine fever virus (csfv) previously described for use on a smartcycler was validated on the applied biosystems ab 7700 sequence detection system using the roche magna pure instrument for nucleic acid extraction and reaction set up. the primers and probe were specific for the csfv strains (nsw, baker and weybridge) and did not react with other pestiviruses (bdv tobias, bdv #327, bvdv non-cpe and bvdv c24v). ana ...	2006	16139899
phylogenetic analysis of recent isolates of classical swine fever virus from colombia.	the ability to discriminate between different classical swine fever virus (csfv) isolates is a prerequisite for identifying the possible origin of an outbreak. to determine the relatedness between colombian isolates from different geographical regions, genetic sequences of the glycoprotein e2 and the 5'utr of csfv were amplified by pcr, sequenced and compared with reference strains of different genetic grouping. the viruses originated from classical swine fever (csf) outbreaks in colombia during ...	2006	16143418
candidate peptide-vaccine induced potent protection against csfv and identified a principal sequential neutralizing determinant on e2.	previously, two candidate multi-peptide-vaccines (mpvs) consisted of five overlapping synthetic peptides covering the antigenic domain b/c (aa693-777) on envelope protein e2 were prepared in our lab. and they successfully induced peptide-specific neutralizing antibodies and provided pigs with complete protection from the lethal challenge of virulent classical swine fever virus (csfv) strain shimen. in this study, these five peptides were conjugated to bovine serum albumin (bsa), with which five ...	2006	16154668
secreted expression of the classical swine fever virus glycoprotein e(rns) in yeast and application to a sandwich blocking elisa.	e(rns) is an envelope glycoprotein of classical swine fever virus (csfv) with rnase activity. the purpose of this study was to produce an active e(rns) for further applications using the yeast secreted expression system. the e(rns) gene was cloned into the expression vector pgapzalphac which was introduced into pichia pastoris. expression of e(rns) protein in culture supernatant was confirmed by western blot analysis using both the monoclonal antibody against csfv e(rns) and csfv-positive swine ...	2006	16213600
in silico studies of the african swine fever virus dna polymerase x support an induced-fit mechanism.	the african swine fever virus dna polymerase x (pol x), a member of the x family of dna polymerases, is thought to be involved in base excision repair. kinetics data indicate that pol x catalyzes dna polymerization with low fidelity, suggesting a role in viral mutagenesis. though pol x lacks the fingers domain that binds the dna in other members of the x family, it binds dna tightly. to help interpret details of this interaction, molecular dynamics simulations of free pol x at different salt con ...	2006	16214865
mutation of e1 glycoprotein of classical swine fever virus affects viral virulence in swine.	transposon linker insertion mutagenesis of a full-length infectious clone (ic) (pbic) of the pathogenic classical swine fever virus (csfv) strain brescia was used to identify genetic determinants of csfv virulence and host range. here, we characterize a virus mutant, rb-c22v, possessing a 19-residue insertion at the carboxyl terminus of e1 glycoprotein. although rb-c22v exhibited normal growth characteristics in primary porcine macrophage cell cultures, the major target cell of csfv in vivo, it ...	2005	16168455
genetic typing of classical swine fever viruses from lao pdr by analysis of the 5' non-coding region.	the 5' non-coding region (5'-ncr) of 27 classical swine fever virus (csfv) isolates from lao people's democratic republic (lao pdr) during 1997 and 1999 were amplified by rt-pcr. a 150-bp region of the 5'-ncr amplicons was analysed and compared with reference csfv of european and asian origin and a phylogenetic dendrogram constructed. following analysis, all viruses were determined to belong to genogroup 2. viruses from lao pdr grouped on a geographical basis with the majority of northern/centra ...	2005	16175340
susceptibility of in vivo- and in vitro-produced porcine embryos to classical swine fever virus.	the objective of this study was to investigate the susceptibility of in vivo- and in vitro-produced (ivp) porcine embryos to classical swine fever virus (csfv). ivp zona pellucida (zp)-intact porcine embryos (n = 721) were co-cultured with csfv for 120 h. after washing according to the international embryo transfer society guidelines (without trypsin) and transferring embryos to csfv-susceptible porcine kidney cells (pk15 cell line), no virus was isolated. however, when 88 ivp zp-intact porcine ...	2005	16149945
role of double-stranded rna and npro of classical swine fever virus in the activation of monocyte-derived dendritic cells.	classical swine fever virus (csfv) is a noncytopathogenic (ncp) positive-sense rna virus that replicates in myeloid cells including macrophages and dendritic cells (dc). the virus does not induce type i interferon (ifn-alpha/beta), which in macrophages has been related to the presence of the viral npro gene. in the present work, the role of viral double-stranded (ds)rna and npro in the virus-host cell interaction has been analyzed. higher levels of detectable dsrna were produced by a genetically ...	2005	16154171
vimentin rearrangement during african swine fever virus infection involves retrograde transport along microtubules and phosphorylation of vimentin by calcium calmodulin kinase ii.	african swine fever virus (asfv) infection leads to rearrangement of vimentin into a cage surrounding virus factories. vimentin rearrangement in cells generally involves phosphorylation of n-terminal domains of vimentin by cellular kinases to facilitate disassembly and transport of vimentin filaments on microtubules. here, we demonstrate that the first stage in vimentin rearrangement during asfv infection involves a microtubule-dependent concentration of vimentin into an "aster" within virus ass ...	2005	16140754
dimerization of glycoprotein e(rns) of classical swine fever virus is not essential for viral replication and infection.	the pestivirus glycoprotein e(rns), a ribonuclease, is expressed on the surface of virions and in infected cells as a disulfide-linked homodimer. e(rns) is involved in the infection process and its rnase activity is probably involved in viral replication and pathogenesis. the most c-terminal cysteine residue forms an intermolecular disulfide bond with another e(rns) monomer, resulting in an e(rns) dimer. to study the function of dimerisation of e(rns) for viral replication, the cysteine residue ...	2005	15986175
[evaluation on the biosafety of classical swine fever dna vaccine].	the biosafety of dna vaccine is one of the key questions which should be solved before it is used in the clinical trail. in order to evaluate the biosafety of dna vaccine, the csfv dna vaccine was used in the studying target, two main aspects of the vaccine were explored in the study. firstly, the possibility of integration of two kinds of dna vaccine plasmids into pig genome was analyzed by pcr technology after the different vaccines were injected through the intramuscular introduction. the res ...	2005	15989279
classical swine fever (csf) in wild boar: the role of the transplacental infection in the perpetuation of csf.	thirty-four pregnant wild sows and their unborn progeny derived from an endemically infected population in the district of nordvorpommern (mecklenburg-western pomerania) were investigated for classical swine fever virus (csfv) and antibodies. during the last 2.5 years of the epidemic, 20 out of 34 pregnant wild sows investigated were serologically positive. no csfv or viral rna was detected in organs derived from these animals and their progeny. this indicates that young wild boars persistently ...	2005	16000110
statistical evaluation of classical swine fever surveillance plans in italy (1995-2003).	summary surveillance plans were carried out in italy from 1995 to 2003, with the main aim of controlling the possible circulation of low-virulence classical swine fever viral strains. the repetition of a serological monitoring programme over several years, with constantly negative results, can prove the absence of the infection while increasing the degree of confidence. in our case, in 2003, after eight repetitions of the surveillance plan, the probability that there was at least one infected fa ...	2005	16000117
enzyme-linked immunosorbent assay based on a chimeric antigen bearing antigenic regions of structural proteins erns and e2 for serodiagnosis of classical swine fever virus infection.	the antigenic region (residues 109 to 160) of classical swine fever virus (csfv) protein e(rns) and the n-terminal antigenic region (residues 1 to 136) of protein e2 were constructed in the form of a fused, chimeric protein, c21e(rns)e2, for use as an enzyme-linked immunosorbent assay (elisa) antigen for the serodiagnosis of csfv infection. tested with 238 negative-field (csfv-free) sera from canadian sources, the specificity of the elisa was determined to be 93.7%. all 20 sera from experimental ...	2005	16002639
lymphocyte apoptosis and thrombocytopenia in spleen during classical swine fever: role of macrophages and cytokines.	thirty-two large white x landrace pigs, 4 months old, were inoculated with the classical swine fever (csf) or hog cholera virus strain "alfort" in order to identify the mechanism responsible for the lymphopenia and thrombocytopenia observed in the spleen during the experimental induction of disease, by immunohistochemical and ultrastructural techniques. results showed a progressive depletion of splenic lymphoid structures and evidence of platelet aggregation processes. lymphoid depletion was due ...	2005	16006607
fc gamma rii-dependent sensitisation of natural interferon-producing cells for viral infection and interferon-alpha responses.	natural interferon-producing cells (nipc), also called plasmacytoid dendritic cells, are the most potent producers of ifn-alpha in response to viral and bacterial components, serving an important function in innate immune defences. the present work demonstrates that nipc responsiveness can be primed by immunisation, increasing their capacity to produce ifn-alpha after viral infection. nipc isolated from pigs immunised against classical swine fever virus (csfv), a member of the flaviviridae, were ...	2005	16021600
de novo rna synthesis and homology modeling of the classical swine fever virus rna polymerase.	classical swine fever virus (csfv) non-structural protein 5b (ns5b) encodes an rna-dependent rna polymerase (rdrp), a key enzyme which initiates rna replication by a de novo mechanism without a primer and is a potential target for anti-virus therapy. we expressed the ns5b protein in escherichia coli. the rgtp can stimulate de novo initiation of rna synthesis and mutation of the gdd motif to gly-asp-asp (gaa) abolishes the rna synthesis. to better understand the mechanism of viral rna synthesis i ...	2005	16022897
outbreaks of classical swine fever in the republic of korea in 2003.		2005	16040944
n(pro) of classical swine fever virus is an antagonist of double-stranded rna-mediated apoptosis and ifn-alpha/beta induction.	classical swine fever virus (csfv) protects cells from double-stranded (ds) rna-mediated apoptosis and ifn-alpha/beta induction. this phenotype is lost when csfv lacks n(pro) (deltan(pro) csfv). in the present study, we demonstrate that n(pro) counteracts dsrna-mediated apoptosis and ifn-alpha/beta induction independently of other csfv elements. for this purpose, we generated porcine sk-6 and pk-15 cell lines constitutively expressing n(pro) fused to the enhanced green fluorescent protein (egfp) ...	2005	16043207
validation of a real-time rt-pcr assay for sensitive and specific detection of classical swine fever.	a fully validated, ready-to-use, real-time reverse transcription-polymerase chain reaction (rt-pcr) assay, multiplexed for simultaneous detection of an internal control, for the simple and rapid diagnosis of classical swine fever (csf) was developed. primers and fam-labeled taqman-probes specific for classical swine fever virus (csfv) were selected from the consensus sequence of the 5' non-translated region (5' ntr) of 78 different csfv strains. for determining analytical sensitivity, an in vitr ...	2005	16055202
in vivo depletion of cd8+ t lymphocytes abrogates protective immunity to african swine fever virus.	to understand the mechanisms involved in protective immunity to african swine fever virus (asfv) infection, the observation that infection with the avirulent portuguese asfv isolate our/t88/3 protects outbred pigs from challenge with the virulent portuguese asfv isolate our/t88/1 was exploited. it was demonstrated that pigs exposed to our/t88/3 and then depleted of cd8+ lymphocytes were no longer fully protected from our/t88/1 challenge. this indicated that cd8+ lymphocytes play an important rol ...	2005	16099902
identification of classical swine fever virus protein e2 as a target for cytotoxic t cells by using mrna-transfected antigen-presenting cells.	vaccination of pigs against classical swine fever virus (csfv) by using live-virus vaccines induces early protection before detectable humoral immune responses. immunological analyses indicate that this is associated with t-cell activation, underlining the importance of targeting cytotoxic t-lymphocyte (ctl) responses for vaccine improvement. antigen-presenting cells (apcs) transfected with mrna encoding structural protein e2 or non-structural viral proteins ns3-ns4a were used to identify viral ...	2005	16099911
genetic characterization of a caprine pestivirus as the first member of a putative novel pestivirus subgroup.	currently, the genus pestivirus comprises four approved species, namely bovine viral diarrhoea viruses 1 and 2 (bvdv-1, bvdv-2), classical swine fever virus and border disease virus (bdv). recently, three major genotypes have been identified within the species bdv and termed as subgroups bdv-1, bdv-2 and bdv-3. here, an isolate from animals in a herd showing bd-like syndromes, which occurred in central italy was analysed. a reverse transcriptase polymerase chain reaction was performed using prim ...	2005	16115092
nictitating membrane as a potentially useful postmortem diagnostic specimen for classical swine fever.	the gold standard for diagnosis of classical swine fever (csf) is cell culture virus isolation combined with reverse transcriptase-polymerase chain reaction (rt-pcr) and fluorescent antibody test (fat) in cryosections of tonsils, spleen, various lymph nodes, ileum, and kidney. autolytic and heterolytic samples render correct fat evaluation difficult and can even yield false-negative or ambiguously positive results. to extend the spectrum of csf diagnostic specimens, the authors tested whether th ...	2005	16130991
long-term monitoring of classical swine fever in wild boar (sus scrofa sp.) using serological data.	in the european community, epizootics of classical swine fever (csf) in the wild boar (sus scrofa) are compulsorily monitored because transmission may occur between wild boars and domestic pigs, causing heavy economic losses to the pork industry. the estimation of incidence in populations of wild boars is generally based on viroprevalence. however, viral isolation becomes rare when the incidence is low because the virus cannot be detected for more than a few weeks following infection. on the con ...	2005	15610721
[identification and comparison of neutralizing epitopes of glycoprotein e(rns) of classical swine fever virus].	structural and envelope glycoprotein e(rns) (gp48) of classical swine fever virus (csfv) is the second antigenic protein being responsible for eliciting neutralizing antibodies and conferring protective immunity. infection of cells with csfv is mediated by the interaction of glycoprotein e(rns) and e2 with the cell surface receptors. the glycoprotein e(rns) has been shown to contain rnase activity, which plays a role in the viral life cycle and is also involved in virus neutralization. neutraliz ...	2005	15847166
origin and evolution of viruses causing classical swine fever in cuba.	we have analyzed the origin and evolution of viruses from the classical swine fever (csf) epidemic that affects cuba since 2001 by nucleotide sequencing of regions within the e2 glycoprotein and the ns5b (polymerase) genes. the sequence of 190 nucleotides from e2 gene was determined for 10 csf viruses isolated at different locations of the island, and used for phylogenetic analyses, including sequences from viruses of the 1993--1997 epizootic, previously determined, as well as those from represe ...	2005	15878213
[sensitivity of methods of titration of the vaccine strain of porcine fever virus].	methods of titration of the cs vaccine strain of classical swine fever virus were compared in vitro and vivo. the titration in the tl and pk-15 cell culture without cytopathic effect is based on the detection of virus antigen by labeled antibodies. the infection intensity in the cell culture virtually correlated with the antigenic and immunogenic activity of dry vaccine used for swine.	2005	15881399
candidate multi-peptide-vaccine against classical swine fever virus induced potent immunity with serological marker.	our previous study proposed a protective multi-peptide-vaccine (mpv) with freund's adjuvant against classical swine fever virus (csfv). in this study, another candidate mpv, using aluminum adjuvant, was further examined. all immunized pigs kept healthy during the experimental period, while the control group rapidly showed clinical symptoms and died. moreover, anti-sera from mpv-immunized pigs could interact with peptides involved in the mpv, in contrast to anti-sera from non-immunized or infecte ...	2005	15882522
a dna vaccine expressing the e2 protein of classical swine fever virus elicits t cell responses that can prime for rapid antibody production and confer total protection upon viral challenge.	immunization of domestic pigs with a dna vaccine expressing the complete e2 protein of classical swine fever virus (csfv) conferred total protection against a severe viral challenge. immunization with three doses of plasmid pcdna3.1/e2 elicited a consistent and specific, mhc class ii restricted t cell response in the three domestic pigs analyzed, in the absence of detectable anti-csfv antibodies in serum. upon challenge specific t cell responses were boosted in the three vaccinated pigs, and a r ...	2005	15882536
loss of interferon regulatory factor 3 in cells infected with classical swine fever virus involves the n-terminal protease, npro.	we show that cells infected with the pestivirus classical swine fever virus (csfv) fail to produce alpha/beta interferon not only following treatment with double-stranded rna but also after superinfection with a heterologous virus, the alphavirus sindbis virus, a virus shown to normally induce interferon. we investigated whether the inhibition of interferon synthesis by csfv involved a block in interferon regulatory factor 3 (irf3) activity. cells infected with csfv exhibited a lack of transloca ...	2005	15890962
evolution of t lymphocytes and cytokine expression in classical swine fever (csf) virus infection.	this study characterized the cell-mediated immune response in pigs inoculated with the alfort 187 isolate of classical swine fever (csf) virus. quantitative changes in the t-lymphocyte population (cd3(+), cd4(+) and cd8(+)) and qualitative changes in cytokine expression (il-2, il-4 and ifngamma) by these cells in serum, thymus and spleen were demonstrated. these changes coincided spatially and temporally with previously described quantitative and qualitative changes in monocyte-macrophage popula ...	2005	15893983
an error-prone viral dna ligase.	our recent demonstration that dna polymerase x (pol x), the dna repair polymerase encoded by the african swine fever virus (asfv), is extremely error prone during single-nucleotide gap filling led us to hypothesize that it might contribute to genetic variability in asfv. for the infidelity of pol x to be relevant, however, the dna ligase working downstream of it would need to be capable of sealing nicks containing 3'-oh mismatches. we therefore examined the nick ligation capabilities of the asfv ...	2005	15938630
monte carlo simulation of classical swine fever epidemics and control. ii. validation of the model.	a stochastic and spatial simulation model was developed to simulate the spread of classical swine fever virus among herds in a certain area. a model is a simplification of a real system. the mechanisms and parameters are often not exactly known. validation is necessary to gain insight into model behaviour and to identify risk factors with great impact on the response variables. several risk factors such as incubation period, number of daily farm contacts, probability of detection, probability of ...	2005	15939558
estimating the probability of freedom of classical swine fever virus of the east-belgium wild-boar population.	a report of the scientific committee on animal health and animal welfare of the european commission (cec, 1999.) includes recommendations for setting up monitoring programmes for classical swine fever (csf) infection in a wild-boar population, based on the assumption that one would detect at least 5% prevalence in a csf-infected wild-boar population. this assumption, however, is not science based. we propose an alternative method to provide evidence for a wild-boar population being free of csf a ...	2005	15953649
immunomodulatory effect of plasmids co-expressing cytokines in classical swine fever virus subunit gp55/e2-dna vaccination.	the aim of this study was to determine the immunomodulatory effects of il-12, il-18 and cd154 (cd40 ligand, cd40l) in dna-vaccination against the classical swine fever virus. four recombinant plasmids were constructed including the csfv coding region for the glycoprotein gp55/e2 alone or together with porcine il-12, il-18 or cd154 genes. five groups of four pigs each were immunized intramuscularly (i.m.) three times with the respective constructs. the control group was inoculated with empty plas ...	2005	15955282
the kinetics of cytokine production and cd25 expression by porcine lymphocyte subpopulations following exposure to classical swine fever virus (csfv).	surface expression of il-2r-alpha (cd25) is widely used to identify activated lymphocyte populations, while interferon-gamma (ifn-gamma) levels have been shown to be a good indicator of cell-mediated immunity (cmi) in pigs. to investigate the relationship between these two parameters, we developed an intracellular cytokine-staining assay and studied the kinetics of cytokine (ifn-gamma and interleukin-10, il-10) production relative to cd25 expression in porcine lymphocyte subpopulations, followin ...	2005	15963818
expression of proinflammatory cytokines by hepatic macrophages in acute classical swine fever.	fourteen pigs were inoculated with the 'alfort 187' strain of classical swine fever (csf) virus and killed in pairs at 2, 4, 7, 9, 11, 14 or 17 days post-inoculation for histopathological, ultrastructural and immunohistochemical examination. for the latter method, the antibodies used were those against viral antigen gp55, porcine myeloid marker swc3, il-1alpha, il-6, tnf-alpha and factor viii-related antigen. activation and increase in the number of hepatic macrophages was observed following vir ...	2005	15899492
monte carlo simulation of classical swine fever epidemics and control. i. general concepts and description of the model.	a monte carlo simulation has been developed to describe the spread of classical swine fever virus between farms within a certain region. the data of the farms can be imported and considered individually. transmission occurs via the infection routes direct animal and indirect person and vehicle contact, as well as by contaminated sperm and local spread. parameters, such as incubation period and probability of detection, can be varied by the user and their impact on disease spread can be studied. ...	2005	15908147
viruses in boar semen: detection and clinical as well as epidemiological consequences regarding disease transmission by artificial insemination.	many viruses have been reported to be present in boar semen, particularly during the viremic phase of the diseases. some of them, such foot-and-mouth disease virus, porcine reproductive and respiratory syndrome virus, swine vesicular disease virus, porcine parvovirus, picornaviruses, adenoviruses, enteroviruses, japanese encephalitis virus, pseudorabies virus, african swine fever virus and reoviruses are of particular importance and accurate monitoring prior to and during the presence of boars i ...	2005	15626416
preclinical diagnosis of african swine fever in contact-exposed swine by a real-time pcr assay.	a fluorogenic probe hydrolysis (taqman) pcr assay for african swine fever virus (asfv) was developed and evaluated in experimentally infected swine. this sensitive and specific one-step single-tube assay, which can be performed in 2 h or less, detected viral dna in tonsil scraping samples 2 to 4 days prior to onset of clinical disease. thus, the assay would have application for preclinical diagnosis of african swine fever and surveillance and/or emergency management of a disease outbreak.	2005	15634958
diagnostic evaluation of a real-time reverse transcriptase pcr assay for detection of classical swine fever virus.	a fluorogenic-probe hydrolysis (taqman)-reverse transcriptase (rt) pcr for classical swine fever virus (csfv) was evaluated for diagnostic sensitivity and specificity by using clinical samples obtained from the dominican republic, where the disease is enzootic. the sensitivity of this test, using nasal swab samples taken from both symptomatic and asymptomatic animals, exceeded the diagnostic sensitivity of virus isolation (100% versus 72.4%, respectively) with little loss of specificity (98.9% v ...	2005	15635018
antibody responses of pigs to defined erns fragments after infection with classical swine fever virus.	antibody responses of pigs to defined erns fragments, after classical swine fever virus (csfv) infection, were studied by using an enzyme-linked immunosorbent assay (elisa). selection of various e(rns) fragments was based on an immunodominant erns region encompassing three overlapping antigenic regions, amino acids 65 to 145 (erns(aa)65-145) (ar1), 84 to 160 (erns(aa)84-160) (ar2), and 109 to 220 (erns(aa)109-220) (ar3), identified earlier by our group (m. lin, e. trottier, j. pasick, and m. sab ...	2005	15643004
cloning and expression of interferon-alpha/gamma from a domestic porcine breed and its effect on classical swine fever virus.	to further evaluate the clinical impact of recombinant poifn-alpha/gamma, poifn-alpha/gamma genes from a chinese domestic big-white porcine breed were cloned using pcr, and expressed in a high-level prokaryotic system. the antiviral activities of rpoifn-alpha/gamma on vesicular stomatitis virus (vsv), porcine reproductive and respiratory syndrome virus (prrsv), and classical swine fever virus (csfv) were investigated in different cell lines. the cloned poifn-alpha gene encodes a protein of 166 a ...	2005	15661333
characterization of helper virus-independent cytopathogenic classical swine fever virus generated by an in vivo rna recombination system.	molecular analyses revealed that most cytopathogenic (cp) pestivirus strains evolve from noncytopathogenic (noncp) viruses by nonhomologous rna recombination. in contrast to bovine viral diarrhea virus (bvdv), cp classical swine fever virus (csfv) field isolates were rarely detected and always represented helper virus-dependent subgenomes. to investigate rna recombination in more detail, we recently established an in vivo system allowing the efficient generation of recombinant cp bvdv strains in ...	2005	15681445
porcine adenovirus as a delivery system for swine vaccines and immunotherapeutics.	porcine adenovirus (padv) has many qualities which make it an ideal choice for use as a delivery vector in swine. it is a low grade pathogen, present almost world-wide in a number of serotypes varying in their virulence and tissue tropism, which may allow for serotype specific vaccine targeting. padv is species specific having only been isolated from swine, reducing the possibility of its spread to other animals or man following administration. when engineered to contain a foreign gene, recombin ...	2005	15683761
phylogenetic analysis of classical swine fever virus in taiwan.	two envelope glycoprotein (erns and e2) regions of the classical swine fever virus (csfv) were amplified by rt-pcr and sequenced directly from 158 specimens collected between 1989 and 2003 in taiwan. phylogenetic analysis of the two regions revealed a similar tree topology and the erns region provided better discrimination than the e2 region. one hundred and fifteen isolates out of the 158 isolates were clustered within subgroup 2.1 (further classified as 2.1a and 2.1b) and 2.2, which were consi ...	2005	15703847
[recombinant analysis of classical swine fever virus].	to study the possible recombinant relationship among differently derived classical swine fever virus, the coding regions of 21 isolates were analyzed to detect recombination and breakpoints through gene trees comparison and quartet analyses. the results show nucleotide area corresponding to e0, e1 and e2 as a possible recombinant tract between ald ( d49532) and gpe-(d49533) while ns5a-ns5b of the isolate 39 (af407339) appears to be derived from a virulent shimen strain (af092448) sequence. this ...	2005	15715438
african swine fever virus infection disrupts centrosome assembly and function.	african swine fever virus (asfv) is a large, enveloped dna virus that assembles in perinuclear sites located close to the centrosome. it is reported here that the microtubule network becomes disorganized soon after the onset of viral dna replication and formation of assembly sites. asfv infection resulted in loss of gamma-tubulin and pericentrin at the centrosome; this was due to protein relocalization, but not degradation. asfv infection also inhibited the ability of the centrosome to nucleate ...	2005	15722518
the e2 glycoprotein of classical swine fever virus is a virulence determinant in swine.	to identify genetic determinants of classical swine fever virus (csfv) virulence and host range, chimeras of the highly pathogenic brescia strain and the attenuated vaccine strain cs were constructed and evaluated for viral virulence in swine. upon initial screening, only chimeras 138.8v and 337.14v, the only chimeras containing the e2 glycoprotein of cs, were attenuated in swine despite exhibiting unaltered growth characteristics in primary porcine macrophage cell cultures. additional viral chi ...	2005	15731272
immunoprotective properties of transgenic plants expressing e2 glycoprotein from csfv and cysteine protease from fasciola hepatica.	immune responses were elicited in laboratory animals after oral vaccination by transgenic plants (lettuce and alfalfa) expressing the e2 glycoprotein of classical swine fever virus (csfv) or cysteine protease from fasciola hepatica. elisa analyses demonstrated that the oral route is effective in inducing a specific antibody response against these antigens in mice.	2005	15734053
[cultivation of the vaccine strain of the virus of porcine classic plague].	several cell cultures were compared and examined for their capability to support reproduction of classical swine fever virus (csfv). experimental conditions of virus cultivation were optimized. the subculture of primary lamb testicular (lt) cells was selected for large cell cultivation of csfv. in contrast to many cell lines, these cells were free of bovine viral diarrhea virus (bvdv) contamination partly due to liquid nitrogen storage and gamma-ray sterilization of serum used in the growth medi ...	2005	15747873
[isolation of classical swine pest virus from homologous and heterologic cell lines].	this study was devoted to the choice of cell line for isolation of cspv with high sensitivity. for this purpose the homologous transplantable cell lines from the collection of european references laboratory of csf (national veterinary research institute, pulawy, poland) and heterological primary cell culture from the collection "biotest-laboratory". cell cultures were cultivated as a monolayer in 96-hole microtitration plates. antigen of csfv was detected in peroxides-linked assay (pla). cell cu ...	2005	15765885
fibrocytes are potent stimulators of anti-virus cytotoxic t cells.	fibrocytes (fb) are a population of circulating leukocytes reported to be capable of presenting antigen to cd4(+) t lymphocytes. in contrast, no information is available about their capacity to stimulate cd8(+) cytolytic t lymphocyte (ctl) responses. to this end, fb were isolated from porcine blood to investigate their ability to stimulate ctl responses using a classical swine fever virus model. the isolated fb (referred to as primary fb) displayed the phenotype previously reported for mouse and ...	2005	15767291
phylogenetic analysis of classical swine fever virus isolated from taiwan.	by analyzing the e2 sequences of classical swine fever virus from field outbreaks in taiwan during 1993-2001, three virus populations with distinct genotypes were determined including one historical (subgroup 3.4) and two exotic (subgroup 2.1) strains. the first subgroup 2.1 virus was isolated in 1994 and further sporadic outbreaks occurred after 1996. phylogenetic analysis using the e2 region has segregated the taiwanese strains of 2.1 virus into two different genotypes (termed 2.1a and 2.1b). ...	2005	15778024
[detection and species-specific differentiation of pestiviruses using real-time rt-pcr].	an important prerequisite for an efficient eradication of pestiviruses like bovine viral diarrhea virus or classical swine fever virus are sensitive and specific detection methods. beside antigen detection with antigen capture elisas and virus isolation using cell culture, the detection of virus genomes by reverse transcriptase polymerase chain reaction (rt-pcr) becomes more and more important. by using real-time rt-pcr, the disadvantages of conventional pcr methods concerning the risk of contam ...	2005	15803758
oronasal vaccination with classical swine fever virus (csfv) replicon particles with either partial or complete deletion of the e2 gene induces partial protection against lethal challenge with highly virulent csfv.	a cdna clone of the classical swine fever virus (csfv) strain alfort/187 [ruggli n, tratschin jd, mittelholzer c, hofmann ma. nucleotide sequence of classical swine fever virus strain alfort/187 and transcription of infectious rna from stably cloned full-length cdna. j virol 1996;70(6):3478-87] was used to construct two e2 deletion mutants lacking either the complete e2 gene or, alternatively, a stretch of 204 nucleotides encoding 68 amino acids located in the c-terminal region of the e2 glycopr ...	2005	15837238
phylogenetic analysis of classical swine fever virus (csfv) field isolates from outbreaks in south and central america.	to date, there is little information concerning the epidemiological situation of classical swine fever (csf) in the americas. besides summarizing the available data, genotyping of isolates from outbreaks in domestic pigs in several countries of south and central america was performed. for this, a 190 base fragment of the e2 envelope glycoprotein gene was used. european strains and isolates, and historical isolates from the united states (us) were included for comparison. in contrast to the situa ...	2005	15845261
evaluation of the epidemiological importance of classical swine fever infected, e2 sub-unit marker vaccinated animals with rt-npcr positive blood samples.	it has been demonstrated that pigs that have been double vaccinated with an e2 sub-unit marker vaccine and that are infected with classical swine fever virus (csfv) through a natural contact infection may react positive in a csfv detecting rt-npcr test, whereas no virus could be isolated by using the conventional virus isolation (vi) technique. to evaluate whether these vaccinated and infected pigs may spread the virus, three experiments were set up. in the first, susceptible pigs were inoculate ...	2005	16283914
[salmonella choleraesuis c500 delivering dna immunization against classical swine fever virus].	classical swine fever virus (csfv) e2 protein eukaryotic expression plasmid pvaxe2 was constructed. the plasmid pvaxe2 was transformed into salmonella choleraesuis c500 (s. c500) attenuated vaccine strain by electroporation to generate salmonella choleraesuis engineering strain s. c500/pvaxe2. the characterization of s. c500/pvaxe2 in morphology, growth, biochemistry and serology indicated that it retained the same properties as its original strain s. c500 with exception of kanamycin resistance ...	2005	16468338
comparison of six rna extraction methods for the detection of classical swine fever virus by real-time and conventional reverse transcription-pcr.	six rna extraction methods, i.e., rnaqueous kit, micro-to-midi total rna purification system, nucleospin rna ii, genelute mammalian total rna kit, rneasy mini kit, and trizol ls reagent, were evaluated on blood and 7 tissues from pig infected with classical swine fever virus (csfv). each of the 6 extraction methods yielded sufficient rna for positive results in a real-time reverse transcription-pcr (rt-pcr) for csfv, and all rna, except the one extracted from blood by trizol ls reagent, yielded ...	2005	16475517
when can a veterinarian be expected to detect classical swine fever virus among breeding sows in a herd during an outbreak?	the herd sensitivity (hse) and herd specificity (hsp) of clinical diagnosis of an infection with classical swine fever (csf) virus during veterinary inspection of breeding sows in a herd was evaluated. data gathered from visits to herds during the csf outbreak in 1997-1998 in the netherlands were used for the analysis. herds were visited one or more times by the same or by different veterinarians. on the basis of the veterinarians' reports, each visit was coded as 0 (negative clinical diagnosis) ...	2004	15737431
development of new concepts in vaccines and their effects on the control of infectious diseases (classical swine fever in particular).	molecular biology and technological advances in dna recombination have ushered in a new era in vaccinology. in particular, "deleted" vaccines have emerged over the past 10 years. the first such vaccines were used to protect pigs against aujeszky's disease. the same principles were subsequently applied to the development of vaccines against classical swine fever (csf), relaunching the debate on whether to use sanitary or medical measures. the decision about the measures to be applied depends on s ...	2004	15742634
adaptation of an invader assay for the detection of african swine fever virus dna.	a closed tube isothermal invader assay (third wave technologies inc., madison, wisconsin, usa) was adapted for the detection of african swine fever virus (asfv) dna. several asfv invader assays were designed successfully and tested on a real-time pcr instrument (icycler, biorad). the assay exhibiting the lowest signal/noise ratio (vp73 asfv invader assay) was analysed further using serial 10-fold dilutions of lisbon 60 asfv viral genome. the assay sensitivity was determined to be in the order of ...	2004	15664044
identification of antigenic regions of the erns protein for pig antibodies elicited during classical swine fever virus infection.	the structural glycoprotein e(rns) of classical swine fever virus (csfv) is one of the major antibody targets upon infection of pigs with the virus. molecular dissection of the structure of e(rns) would define the minimal immunodominant regions that induce antibody responses after infection and may thus help design an effective diagnostic reagent or vaccine. in this study, deletion analysis was made within amino acids (aa) 297 to 776 of the csfv alfort/187 polyprotein containing the large c-term ...	2004	15671490
african swine fever virus multigene family 360 genes affect virus replication and generalization of infection in ornithodoros porcinus ticks.	recently, we reported that african swine fever virus (asfv) multigene family (mgf) 360 and 530 genes are significant swine macrophage host range determinants that function by promoting infected-cell survival. to examine the function of these genes in asfv's arthropod host, ornithodoros porcinus porcinus, an mgf360/530 gene deletion mutant (pr4delta35) was constructed from an asfv isolate of tick origin, pr4. pr4delta35 exhibited a significant growth defect in ticks. the deletion of six mgf360 an ...	2004	14963141
neutralizing antibodies to african swine fever virus proteins p30, p54, and p72 are not sufficient for antibody-mediated protection.	although antibody-mediated immune mechanisms have been shown to be important in immunity to asf, it remains unclear what role virus neutralizing antibodies play in the protective response. virus neutralizing epitopes have been identified on three viral proteins, p30, p54, and p72. to evaluate the role(s) of these proteins in protective immunity, pigs were immunized with baculovirus-expressed p30, p54, p72, and p22 from the pathogenic african swine fever virus (asfv) isolate pr4. asfv specific ne ...	2004	14980493
characterization of functional hepatitis c virus envelope glycoproteins.	hepatitis c virus (hcv) encodes two envelope glycoproteins, e1 and e2, that assemble as a noncovalent heterodimer which is mainly retained in the endoplasmic reticulum. because assembly into particles and secretion from the cell lead to structural changes in viral envelope proteins, characterization of the proteins associated with the virion is necessary in order to better understand how they mature to be functional in virus entry. there is currently no efficient and reliable cell culture system ...	2004	14990718
the effect of highly active antiretroviral therapy for hiv on the anti-hcv specific humoral immune response.	the effect of highly active antiretroviral therapy (haart) on hcv replication is controversial, with some studies reporting no effect and others increases, reductions and even clearances of hcv rna after treatment. in this study, the effect of haart was investigated on the titre of anti-hcv specific antibodies and on the relationship between these antibodies and hcv rna level in a cohort of 24 patients with inherited bleeding disorders. a significant inverse correlation between antibodies to bot ...	2004	14695658
what determines whether mammalian ribosomes resume scanning after translation of a short upstream open reading frame?	if the 5'-proximal aug triplet in a mammalian mrna is followed by a short open reading frame (sorf), a significant fraction of ribosomes resume scanning after termination of sorf translation, and reinitiate at a downstream aug. to examine the underlying mechanism, we examined reinitiation in vitro using a series of mrnas that differed only in the 5'-untranslated region (utr). efficient reinitiation was found to occur only if the eif4f complex, or at a minimum the central one-third fragment of ei ...	2004	14701882
apoptosis of thymocytes in experimental african swine fever virus infection.	this paper report on the lesions occurred in the thymus in experimental acute african swine fever (asf). twenty-one pigs were inoculated with the highly virulent asf virus (asfv) isolate spain-70. animals were slaughtered from 1 to 7 days post infection (dpi). three animals with similar features were used as controls. thymus samples were fixed in 10% buffered formalin solution for histological and immunohistochemical study and in 2.5% glutaraldehyde for ultrastructural examination. for immunohis ...	2004	14702174
the cd2v protein of african swine fever virus interacts with the actin-binding adaptor protein sh3p7.	the predicted extracellular domain of the cd2v protein of african swine fever virus (asfv) shares significant similarity to that of the cd2 protein in t cells but has a unique cytoplasmic domain of unknown function. here we have shown that cd2v is expressed as a glycoprotein of approximately 105 kda in asfv-infected cells. in the absence of an extracellular ligand, the majority of cd2v appears to localize to perinuclear membrane compartments. furthermore, we have shown using the yeast two-hybrid ...	2004	14718626
cd81 is required for hepatitis c virus glycoprotein-mediated viral infection.	cd81 has been described as a putative receptor for hepatitis c virus (hcv); however, its role in hcv cell entry has not been characterized due to the lack of an efficient cell culture system. we have examined the role of cd81 in hcv glycoprotein-dependent entry by using a recently developed retroviral pseudotyping system. human immunodeficiency virus (hiv) pseudotypes bearing hcv e1e2 glycoproteins show a restricted tropism for human liver cell lines. although all of the permissive cell lines ex ...	2004	14722300
african swine fever virus multigene family 360 and 530 genes affect host interferon response.	african swine fever virus (asfv) multigene family 360 and 530 (mgf360/530) genes affect viral growth in macrophage cell cultures and virulence in pigs (l. zsak, z. lu, t. g. burrage, j. g. neilan, g. f. kutish, d. m. moore, and d. l. rock, j. virol. 75:3066-3076, 2001). the mechanism by which these novel genes affect virus-host interactions is unknown. to define mgf360/530 gene function, we compared macrophage transcriptional responses following infection with parental asfv (pr4) and an mgf360/5 ...	2004	14747550
tick-borne viruses.	at least 38 viral species are transmitted by ticks. virus-tick-vertebrate host relationships are highly specific and less than 10% of all tick species (argasidae and ixodidae) are known to play a role as vectors of arboviruses. however, a few tick species transmit several (e.g. ixodes ricinus, amblyomma variegatum) or many (i. uriae) tick-borne viruses. tick-borne viruses are found in six different virus families (asfarviridae, reoviridae, rhabdoviridae, orthomyxoviridae, bunyaviridae, flaviviri ...	2004	15938513
[ubiquitin-proteasome pathway and virus infection].	ubiquitin is highly conserved 76 amino acid protein found in all eukaryotic organisms and ubiquitin-proteasome pathway (upp) plays a very important role in regulated non-lysosomal atp dependent protein degradation. this pathway participates in or regulates numerous cellular processes, such as selective protein degradation, cell cycle progression, apoptosis, signal transduction, transcriptional regulation, receptor control by endocytosis, immune response and the processing of antigens. neverthele ...	2004	15969100
classical swine fever--a step closer.		2004	15977610
vaccination against classical swine fever virus: limitations and new strategies.	the most widely used vaccines for the control of classical swine fever (csf) in countries where it is endemic are live attenuated virus strains, which are highly efficacious, inducing virtually complete protection against challenge with pathogenic virus. in the european union (eu), the combination of prophylactic mass vaccination and culling of infected pigs in endemic regions has made it possible to almost eradicate the disease. however, it is not possible to discriminate between infected and v ...	2004	15984328
detection of classical swine fever virus in archival formalin-fixed tissues by reverse transcription-polymerase chain reaction.	classical swine fever (csf) is an economically important office international des epizooties list a disease of swine. inadequate diagnostic infrastructure in developing countries may sometimes make the conduit of viable samples to diagnostic laboratories difficult and at times formalin-fixed tissues may be the only morbid materials available which are not amenable to most laboratory tests. the potential diagnostic abilities in such situations would be enhanced if a highly sensitive and specific ...	2004	15894029
quality management in reference tests for the diagnosis of classical swine fever.	inter-laboratory comparison tests for the diagnosis of classical swine fever (csf) have been established by the national swine fever laboratories of european union (eu) member states. they provide a method of measuring both the quality of the results of diagnostic tests performed by laboratories and the competence with which they were performed. the objective is that all laboratories obtain the same result when investigating the same sample. this study evaluates the results of serological and vi ...	2004	15861884
codon-optimized cloning, expression and characertization of the c-terminal region of human apoptotic protein gadd34 in escherichia coli.	the human gadd34 (growth arrest and dna damage-inducible 34) is the product of an apoptosis- and dna-damage-inducible gene. the c-terminus domain of gadd34 is highly homologous to hsv-1 gamma-1 34.5, hsv-2 and the african swine fever virus virulence-associated factor nl-s. among these viral proteins, hsv-1 gamma 34.5 protein is known to prevent apoptosis of viral-infected cells. because of the difficulty in expressing gadd34 protein or any of its fragments, including the c-terminus (amino acids ...	2004	14657671
attenuation of classical swine fever virus by deletion of the viral n(pro) gene.	we have reported earlier that replacement of the n(pro) gene of classical swine fever virus (csfv) by the murine ubiquitin gene only slightly affects the characteristics of virus replication in the porcine kidney cell line sk-6 [j. virol. 72 (1998) 7681]. here, for the moderately virulent csfv strain alfort/187 as well as for the highly virulent strain eystrup we show that the respective n(pro)-deleted viruses are attenuated. vaccination of pigs with either of the two deletion mutants resulted i ...	2004	14670312
the subcellular distribution of multigene family 110 proteins of african swine fever virus is determined by differences in c-terminal kdel endoplasmic reticulum retention motifs.	african swine fever virus (asfv) is a large double-stranded dna virus that replicates in discrete areas in the cytosol of infected cells called viral factories. recent studies have shown that assembling virions acquire their internal envelopes through enwrapment by membranes derived from the endoplasmic reticulum (er). however, the mechanisms that underlie the formation of viral factories and progenitor viral membranes are as yet unclear. analysis of the published genome of the virus revealed a ...	2004	15016891
inclusion bodies from recombinant bacteria as a novel system for delivery of vaccine antigen by the oral route.	a fragment of non-glycosylated e2 antigen of classical swine fever virus (csfv), lacking the trans-membrane anchor (tm-) of the native glycoprotein, was produced in recombinant escherichia coli strain bl21(de3) in the form of inclusion bodies. these inclusion bodies isolated from the bacteria cells were administrated orally to mice twice at either 10 or 50 microg per dose. each mouse fed with inclusion bodies carrying the e2 antigen responded with plasma antibodies and/or fecal iga at least once ...	2004	15019290
scenario tree modeling to analyze the probability of classical swine fever virus introduction into member states of the european union.	the introduction of classical swine fever virus (csfv) into a country free of disease without vaccination may have huge consequences in terms of both disease spread and economic losses. more quantitative insight into the main factors determining the probability of csfv introduction (pcsfv) is needed to optimally use resources for the prevention of csfv introduction. for this purpose a spreadsheet model was constructed that calculates the annual pcsfv into member states of the european union (eu) ...	2004	15028015
cytopathogenicity of classical swine fever viruses that do not show the exaltation of newcastle disease virus is associated with accumulation of ns3 in serum-free cultured cell lines.	pestiviruses can be distinguished as two biotypes, cytopathogenic (cp) and noncytopathogenic (noncp), by the morphological changes that they induce during growth in cultured cells. in this study, the cp phenotype of several classical swine fever viruses (csfv) was evaluated by the detections of the nonstructural proteins ns2-3 and ns3 using immunoprecipitation and western blotting in different porcine cell lines. most csfvs that showed the exaltation of newcastle disease virus (end) phenomenon ( ...	2004	15031544
does multiple oral vaccination of wild boar against classical swine fever (csf) have a positive influence on the immunity?	we studied the efficacy of multiple vaccinations of wild boar against classical swine fever (csf) using a c-strain vaccine. the study consisted of two experiments. in the first experiment, 7 to 8 months old animals were vaccinated either three or four times at an interval of 7 days or twice at an interval of 14 or 28 days. in the second experiment, the efficacy of oral immunisation in young boars (3 months old) was examined after fivefold vaccination at intervals of 14 or 28 days. independently ...	2004	15032263
classical swine fever virus induces proinflammatory cytokines and tissue factor expression and inhibits apoptosis and interferon synthesis during the establishment of long-term infection of porcine vascular endothelial cells.	infection with virulent strains of classical swine fever virus (csfv) results in an acute haemorrhagic disease of pigs, characterized by disseminated intravascular coagulation, thrombocytopenia and immunosuppression, whereas for less virulent isolates infection can become chronic. in view of the haemorrhagic pathology of the disease, the effects of the virus on vascular endothelial cells was studied by using relative quantitative pcr and elisa. following infection, there was an initial and short ...	2004	15039545
exceptionally diverse morphotypes and genomes of crenarchaeal hyperthermophilic viruses.	the remarkable diversity of the morphologies of viruses found in terrestrial hydrothermal environments with temperatures >80 degrees c is unprecedented for aquatic ecosystems. the best-studied viruses from these habitats have been assigned to novel viral families: fuselloviridae, lipothrixviridae and rudiviridae. they all have double-stranded dna genomes and infect hyperthermophilic crenarchaea of the orders sulfolobales and thermoproteales. representatives of the different viral families share ...	2004	15046572
african swine fever virus structural protein p54 is essential for the recruitment of envelope precursors to assembly sites.	the assembly of african swine fever virus (asfv) at the cytoplasmic virus factories commences with the formation of precursor membranous structures, which are thought to be collapsed cisternal domains recruited from the surrounding endoplasmic reticulum (er). this report analyzes the role in virus morphogenesis of the structural protein p54, a 25-kda polypeptide encoded by the e183l gene that contains a putative transmembrane domain and localizes at the er-derived envelope precursors. we show th ...	2004	15047843
comparison of reverse transcriptase-polymerase chain reaction, virus isolation, and immunoperoxidase assays for detecting pigs infected with low, moderate, and high virulent strains of classical swine fever virus.	pigs were experimentally inoculated with glentorf, lelystad/97, and alfort/187: representative low, moderate, and high virulent strains of classical swine fever virus (csfv). animals were tested for viremia using virus isolation and reverse transcriptase-polymerase chain reaction (rt-pcr) assays run under routine diagnostic conditions. the virus was detected in the peripheral blood by virus isolation and rt-pcr assays of all glentorf- and lelystad/97-infected pigs beginning at 3 days postinocula ...	2004	15053364
an avirulent chimeric pestivirus with altered cell tropism protects pigs against lethal infection with classical swine fever virus.	a chimeric pestivirus was constructed using an infectious cdna clone of bovine viral diarrhea virus (bvdv) [j. virol. 70 (1996) 8606]. after deletion of the envelope protein e2-encoding region, the respective sequence of classical swine fever virus (csfv) strain alfort 187 was inserted in-frame resulting in plasmid pa/cp7_e2alf. after transfection of in vitro-transcribed cp7_e2alf rna, autonomous replication of chimeric rna in bovine and porcine cell cultures was observed. efficient growth of ch ...	2004	15063124
influence of a 12-nt insertion present in the 3' untranslated region of classical swine fever virus hclv strain genome on rna synthesis.	the function of a 12-nt insertion 'cttttttctttt' in the 3' untranslated region (3'utr) of the hclv strain, a vaccine strain derived from the shimen strain of classical swine fever virus (csfv), was examined in vitro. rna synthesis increased when the 12-nt insertion was deleted from the 3'utr of the hclv strain. rna synthesis also decreased when the 12-nt insertion was introduced into the 3'utr of the csfv shimen, virulent strain. therefore, the 12-nt insertion present in the 3'utr of the hclv st ...	2004	15084401