evolution of a common structural core in the internal ribosome entry sites of picornavirus.the translational control involving internal ribosome binding occurs in poliovirus (pv), human rhinoviruses (hrv), encephalomyocarditis virus (emcv), foot-and-mouth disease virus (fmdv), and hepatitis a virus (hav). internal ribosome binding utilizes cis-acting genetic elements of approximately 450 nucleotides (nt) termed the internal ribosome entry sites (ires) found in these picornaviral 5'-untranslated region (5'utr). although these ires elements are quite different in their primary sequence, ...19989562889
homologous and heterologous antibody response of cattle and sheep after vaccination with foot and mouth disease and influenza viruses.homologous and heterologous antibody response to fmd and influenza vaccines was studied in 37 calves and 45 lambs at the age of 2 months. the fmd and influenza monovalent killed vaccines were administered simultaneously twice. another group of 18 calves was vaccinated twice, first at the age of 2 months and second at the age of 6 months, with trivalent fmd vaccine. the antibody titers were measured by elisa and hi after second vaccination, for fmdv and influenza, respectively. the conclusions of ...19989569464
induction of anti foot and mouth disease virus t and b cell responses in cattle immunized with a peptide representing ten amino acids of vp1.we previously demonstrated that the immunization of cattle with a synthetic peptide representing the amino acid sequence of foot and mouth disease virus (fmdv) type o1 campos vp1 residues 135-160 (p135-160), containing immunodominant t and b epitopes, was able to induce a strong neutralizing antibody (na) response. the epitope mapping of p135-160 identified t and b epitopes in the area restricted to amino acid residues 135-144 (zamorano et al. 1994, virology 201; 1995, virology 212). we are now ...19989569465
inhibition of foot and mouth disease virus (fmdv) uncoating by a plant-derived peptide isolated from melia azedarach l leaves.meliacine (ma), a peptide isolated from leaves of the high plant melia azedarach l inhibited the multiplication of foot and mouth disease virus (fmdv) in bhk-21 cells. in this report, we establish that the ma-inhibitable process takes place within the first hour of the viral reproductive cycle. ma had no virucidal effect and did not affect adsorption and penetration of the virus in cells. in experiments with neutral red-labeled virus, it was found that ma significantly suppressed the development ...19989572558
recognition of picornavirus internal ribosome entry sites within cells; influence of cellular and viral proteins.the ability of different picornavirus internal ribosome entry site (ires) elements to direct initiation of protein synthesis has been assayed in different cell lines in the presence and absence of viral proteases that inhibit cap-dependent protein synthesis. reporter plasmids that express dicistronic mrnas, containing different ires elements, with the general structure cat/ires/luc, have been assayed. in each plasmid, the cat sequence encodes chloramphenicol acetyl transferase and the luc sequen ...19989582094
[physico-chemical bases of the mechanism of thermal inactivation of the foot-and-mouth disease virus].experiments demonstrated that the effect of water activity on the solvate complex of virions underlies the mechanism of thermal inactivation of the foot and mouth disease virus in suspension; changes in the structure of the complex impair the electrophysical balance of the rna-protein relations and hence, destroy the virus. heating of virus-containing suspensions at moderate positive temperatures leads to destruction of the noninfectious part of virus population of 146s particles, thus decreasin ...19989606878
host factors affecting the homologous and heterologous immune response of cattle to fmdv: genetic background, age, virus strains and route of administration.sixty bulls were tested for antibodies to the heterologous serotype c1 of fmdv following repeatable vaccinations with a commercial trivalent vaccine (o1, a22, asia1). six (10%) bulls were found to possess rather high levels of heterologous neutralizing antibodies which showed accumulative trend with age. two high positive and two negative bulls for the heterologous serotype c1 were selected for progeny test involving ten daughters of each bull. the four bulls, either positive or negative for the ...19989607052
evaluation of primers for pcr amplification of rna polymerase gene sequences of foot-and-mouth disease virus.eight oligonucleotide primers in 7 different combinations were used to amplify 3d gene sequences of foot-and-mouth disease virus (fmdv) by reverse transcription-polymerase chain reaction (rt-pcr). six of the primers were designed at this laboratory. all the primer combinations could specifically amplify 3d gene sequences of fmdv serotypes o, a, and c. the largest fragment amplified was of 1,393 bp and the smallest was of 208 bp in size. the 1,393 bp fragment included sequences from the preceedin ...19979607092
the foot and mouth disease virus type o outbreak of 1992 is not related to vaccine strain (o/r2/75).vaccination is the only pragmatic approach to control foot and mouth disease in india. strict quality control measures are essential to supply potent vaccine to the field application, in addition to monitoring the performance of the vaccine in the field. during the process of monitoring, an outbreak of fmd in vaccinated animals caused by type "o" virus in tanjavur district of tamil nadu and a type "o" virus from unvaccinated herd of karnataka were studied. field isolates and vaccine virus were s ...19989608661
vp1-coding sequences of recent isolates of foot-and-mouth disease virus types a, o and asia1.a large part of the capsid protein vp1-coding sequence of foot-and-mouth disease virus, isolated between 1993 and 1996 in europe, was amplified by the reverse transcription-dependent polymerase chain reaction (rt-pcr). the same was done with some non-european virus isolates, especially those against which vaccines were currently produced. the products were sequenced, and the sequences aligned. the alignment comprises sequences of the types a, o and asia 1. although the provenance of virus introd ...19989608664
[molecular basis of changes in biological properties of foot and mouth disease virus of subtype a22].primary structure of capsid proteins and rna polymerase of three closely related strains of foot and mouth disease virus (fmdv), subtype a22, differing by biological properties (the initial epitheliotropic strain a22 550 and its derivatives: thermoresistant myotropic a22 550/4 and thermosensitive attenuated a22 645) are compared by nucleic acid sequencing and analysis of the amino acid sequencing. the study revealed 1 substitute in vpi and 8 in rna polymerase in the myotropic variant and 1 subst ...19989611758
mutational analysis of discontinuous epitopes of foot-and-mouth disease virus using an unprocessed capsid protomer unprocessed capsid precursor (p1) of foot-and-mouth disease virus (fmdv) has been expressed in mammalian cells to study discontinuous epitopes involved in viral neutralization. amino acid replacements found in virus-escape mutants were engineered in the p1 precursor by site-directed mutagenesis of the plasmid. in all cases the replacements abolished recognition of unprocessed p1 by the relevant monoclonal antibodies (mabs), paralleling the effects of the corresponding substitutions in neutral ...19989617767
detection and characterization of foot-and-mouth disease virus in sub-saharan africa.genomic amplification of the vp1 gene of sat-type foot-and-mouth disease virus (fmdv) was performed with published and novel oligonucleotide primers. the primer pair with the highest sat-type recognition (67%) was identified and selected for optimization. modifications to primers significantly improved sat-type detection (100%), broadened the recognition range to european (a, o and c) and asian (asia-1) serotypes and improved test sensitivity. in addition to being able to confirm the presence of ...19989629589
improved mimicry of a foot-and-mouth disease virus antigenic site by a viral peptide displayed on beta-galactosidase surface.a major antigenic site (site a) of foot-and-mouth disease virus includes multiple overlapping epitopes located within the flexible g-h loop of capsid protein vp1. we have studied the antigenicity of several recombinant e. coli beta-galactosidases displaying the site a from a serotype c virus in different surface regions of the bacterial enzyme. in each one of the explored insertion sites, the recombinant peptide shows different specificity with a set of anti-virus monoclonal antibodies directed ...19959634810
a universal virus inactivant for decontaminating blood and biopharmaceutical products.removal of virus infectivity from blood and biopharmaceutical products prepared from blood is an issue of considerable importance. for biopharmaceutical products, removal can usually be achieved by a series of fractionation steps or by inactivation with a suitable reagent. irrespective of the methods that are chosen it is vital that the biological activity of the product is not impaired. for blood and unfractionated plasma or serum, the problem is even more challenging. selective inactivation of ...19989637748
antibody to the nonstructural proteins of foot-and-mouth disease virus in vaccinated animals exposed to infection.cattle which have been infected with foot-and-mouth disease (fmd) virus can be differentiated from those that have been vaccinated on the basis of the detection of antibody to one or more of the non-structural (ns) proteins of the virus. cattle which have been protected by vaccination can become persistently infected with fmd virus (fmdv) without ever showing clinical signs. vaccinated, protected cattle which are persistently infected cannot be distinguished from animals that merely have been va ...19989652054
differentiating foot-and-mouth disease virus-infected from vaccinated animals with baculovirus-expressed specific proteins.we had shown in preliminary studies with a small number of animals that antibodies against 2c could be detected in cattle and pigs which had been infected with fmdv but not in animals which had been vaccinated against the disease. to determine whether this test was generally applicable, sera from several hundred animals which had been vaccinated with different products in many countries have been tested in an elisa using baculovirus expressed 2c. our results show that only 1-2% of the sera gave ...19989652055
cattle response to foot-and-mouth disease virus nonstructural proteins as antigens within vaccines produced using different concentrations.four groups of ten nine-month-old nelore heifers were used for this study. each group received one of four foot-and-mouth disease (fmd) trivalent vaccines for the duration of the experiment. the four vaccine formulations (normal, 2x, 4x and 8x) differed in 140s content to determine the serological reactivities to fmd virus (fmdv) nonstructural proteins 2c, 3abc and 3d. vaccination was by the intramuscular administration of vaccine on day 0, 180 and 360. bleedings were done at 30 days post vaccin ...19989652056
diagnostic potential of mab-based elisas for antibodies to non-structural proteins of foot-and-mouth disease virus to differentiate infection from vaccination.this paper summarises the development of monoclonal antibody (mab)-based immunoassays measuring antibodies to non-structural proteins of fmdv to differentiate infection from vaccination. of the three non-structural proteins 2c, 3c and 3abc evaluated in this study, the polypeptide 3abc was the most immunogenic. three elisas for the detection of antibodies to 3abc were developed. two assays rely on the competition of test sera against either a anti-3a mab or against antisera to 3abc raised in rabb ...19989652058
detection of cattle exposed to foot-and-mouth disease virus by means of an indirect elisa test using bioengineered nonstructural polyprotein 3abc. 19989652059
rt-pcr in foot-and-mouth disease diagnosis.a rt-pcr assay for the specific detection of rna sequences from foot-and-mouth disease virus (fmdv) has been developed. the procedure permits also the detection of sequences that correlate with established fmdv serotypes. a computer program that allows selection of genotype-specific primers for rt-pcr amplification was used for the identification of fmdv specific sequences for pcr amplification on rna replicase (3d) gene regions. specific, rapid and highly sensitive detection was achieved for a ...19989652064
detection of foot-and-mouth disease by reverse transcription polymerase chain reaction and virus isolation in contact sheep without clinical signs of foot-and-mouth disease.two non-vaccinated sheep were experimentally infected with fmdv and one day later 4 other sheep were brought in contact. although the contact sheep showed no clinical signs, serology indicated that all sheep became infected. various secretion samples, taken over a period of at least one month, and various tissue samples were examined for the presence of fmdv by rt-pcr and by virus isolation. fmdv was most often found in saliva (mouth swabs), followed by nasal secretion and sera. faecal material, ...19989652065
influence of il-12 on interferon-gamma production by bovine leucocyte subsets in response to bovine respiratory syncytial virus.the cytokine il-12 is a key molecule in the regulation of cd4+ t cell development and specifically potentiates the development of t helper 1 responses in mouse and man. however the biological effects mediated by bovine il-12 have not been defined in cattle. to produce the expression of the two mature proteins a polyprotein approach was used. this system is employed by positive strand viruses and encodes both products from a single open reading frame (orf). the 2a region of foot-and-mouth disease ...19989656442
multiple virulence determinants of foot-and-mouth disease virus in cell culture.hypervirulent variants of foot-and-mouth disease virus (fmdv) of serotype c arise upon serial cytolytic or persistent infections in cell culture. a specific mutation in the internal ribosome entry site of persistent fmdv was previously associated with enhanced translation initiation activity that could contribute to the hypervirulent phenotype for bhk-21 cells. here we report that several hypervirulent fmdv variants arising upon serial cytolytic passage show an invariant internal ribosome entry ...19989658076
monoclonal antibodies, against o1 serotype foot-and-mouth disease virus, from a natural bovine host, recognize similar antigenic features to those defined by the mouse.eight neutralizing and two non-neutralizing anti-foot-and-mouth disease virus (fmdv) bovine igg1 and igg2 monoclonal antibodies (bmabs) recognize conformationally dependent epitopes. the majority of those shown to neutralize virus passively protected mice from virus challenge, regardless of isotype. well-characterized anti-fmdv mouse mabs, representing five independent neutralizing epitopes on o1 serotype virus, were examined with each of the ten bmabs in a competition-based elisa. five of the n ...19989680132
in vivo analysis of the stability and fitness of variants recovered from foot-and-mouth disease virus quasispecies.we have analysed the ability to infect pigs of two foot-and-mouth disease virus (fmdv) variants isolated at low frequencies from virus populations (quasispecies) generated in pigs on infection with a parental virus, c-s8c1. a monoclonal antibody-resistant mutant (marm21), and a variant isolated at early times post-infection (s-3t1), each exhibiting a unique amino acid substitution in vp1, were able to cause disease in pigs, both by direct inoculation or by contact transmission. the symptoms deve ...19989680133
the biological relevance of virus neutralisation sites for virulence and vaccine protection in the guinea pig model of foot-and-mouth disease.five neutralisation epitopes have been defined for the o1 kaufbeuren strain of foot-and-mouth disease virus (fmdv) by neutralising murine monoclonal antibodies (mabs). a mutant virus which is resistant to all these mabs also resists neutralisation by bovine polyclonal sera, and this characteristic was exploited in the current study to investigate the biological relevance of neutralisation sites in fmdv virulence and vaccine protection. the five site neutralisation-resistant mutant was shown to b ...19989683571
biosensor characterization of antigenic site a of foot-and-mouth disease virus presented in different vector systems.the region 141-160 of the vp1 protein of foot-and-mouth disease virus known as site a is an immunodominant region that has been extensively studied for the purpose of developing a synthetic vaccine. in the present study, site a of foot-and-mouth disease virus was inserted in three different loops of the maltose-binding protein and its antigenicity was compared with site a presented as a conjugated synthetic peptide or inserted in beta-galactosidase. the affinity of antibodies elicited against th ...19989684999
a rt-pcr assay for the differential diagnosis of vesicular viral diseases of swine.a rt-pcr assay based on specific amplification of rna sequences from each of the etiological agents of three important vesicular diseases that affect swine, foot-and-mouth disease virus (fmdv), swine vesicular disease virus (svdv), and vesicular stomatitis virus (vsv), was developed. genotype-specific primers that amplified dna fragments of differential size from svdv 3d gene or vsv l gene were selected with the aid of a computer program. experimental testing of the primers predicted as svdv-spe ...19989694330
quantitation of foot-and-mouth disease virus genomes in bovine tissue by competitive rt-pcr.the sensitivity of a reverse transcription-dependent polymerase chain reaction (rt-pcr) for detecting foot-and-mouth disease virus (fmdv) genomes was quantified by use of rna transcribed in vitro from fmdv-specific cdna. previously, the cdna had been elongated by 228 base pairs. the minimum number of template molecules required to obtain the specific rt-pcr product was determined to be 10(4). this was achieved by use of 1 microg of primer for cdna synthesis and by undertaking of at least 30 cycl ...19989694331
protection of swine by live and inactivated vaccines prepared from a leader proteinase-deficient serotype a12 foot-and-mouth disease virus.previously, we demonstrated that a genetically engineered variant of foot-and-mouth disease virus (fmdv) serotype a12 lacking the leader proteinase-coding region (a12-llv2) was attenuated and induced an immune response that partially protected cattle from fmd. in this study, a12-llv2 was tested in swine as a live or chemically inactivated vaccine. animals vaccinated with chemically inactivated a12-llv2 or wild-type (wt) virus in oil adjuvant developed high levels of neutralizing antibodies and w ...19989711798
construction and evaluation of an attenuated vaccine for foot-and-mouth disease: difficulty adapting the leader proteinase-deleted strategy to the serotype o1 virus.over the last few years we have utilized a system to genetically engineer foot-and-mouth disease virus (fmdv) to produce live-attenuated vaccine candidates. these candidates have been generated in the genetic background of a tissue culture-adapted strain of serotype a12 virus. based on this a12 system, we created a virus lacking the sequence encoding the leader (l) proteinase (piccone et al., 1995), and demonstrated that this leaderless virus, a12-llv2 was avirulent in bovine and swine, and coul ...19989712511
modulation of the antigen presentation activity in foot and mouth disease virus (fmdv) vaccines by two adjuvants: avridine and a water soluble fraction of mycobacterium sp.we have previously demonstrated that the presence of the antigen presenting cells (apc) is critical in the induction and maintenance of the immune response in animals infected or immunized with inactivated fmdv. the use of immunological adjuvants has been repeatedly shown to be essential for the improvement of the immunogenicity in fmdv vaccines. specifically, we have previously shown that the addition of the synthetic lipoamide avridine (avr) or a water soluble fraction of mycobacterium sp. (ws ...19989713938
d-peptides as immunogens and diagnostic reagents.there has been a regain of interest in the immunological applications of peptides assembled partly or totally from d-amino acids. such peptides are much more stable to proteolysis than natural l-peptides and they have considerable potential as synthetic vaccines and as immunomodulators in t-cell responses. retro-inverso, also called retro-all-d or retroenantio, peptide analogues that closely mimic the structure of protein antigens are obtained by assembling amino acid residues in the reverse ord ...19989720264
genetic heterogeneity of indian field isolates of foot-and-mouth disease virus serotype o as revealed by partial sequencing of 1d gene.the sequence of 165 nucleotides at the 3' end of the 1d gene, determined from rt pcr amplified cdna fragments, of 25 type o strains isolated from different parts/regions of india during 1987 1995 and the vaccine strain (r2/75) currently in use in india were subjected to phylogenetic analysis. one isolate from the neighbouring country nepal was also included in the study. the virus/ field strains showed high degree of genetic heterogeneity among themselves with % divergence in nucleotide sequence ...19989725665
problems with bhk 21 cells.the properties of baby hamster kidney (bhk 21) cells are modified by passage in suspension culture. the suspended cells differ from monolayer cells in the surface expression of some integrin chains involved in attachment of foot-and-mouth disease virus (fmdv), in particular the progressive down-regulation of both alpha5 and alphav integrin chains. this down-regulation is correlated with the loss of actin stress fibres. fmdv particles from these cells are unstable towards the aziridine used in in ...19989737382
differentiation of infection from vaccination in foot-and-mouth disease by the detection of antibodies to the non-structural proteins 3d, 3ab and 3abc in elisa using antigens expressed in baculovirus.the baculovirus expression system was found to be efficient at expressing the 3d, the 3ab and the 3abc non-structural proteins (nsp) of foot-and-mouth disease virus (fmdv) as antigens recognised by immune sera in elisa. elisa's using 3d, 3ab and 3abc detected antibodies from day 8 and 10 after experimental infection of susceptible cattle and sheep and cattle remained seropositive for more than 395 days. the elisa's detected antibodies against any of the seven serotypes of fmdv. the 3d elisa was ...19989739326
inactivation of foot-and-mouth disease virus by heat, formaldehyde, ethylene oxide and gamma radiation. 19989746947
vaccinia virus protein synthesis has a low requirement for the intact translation initiation factor eif4f, the cap-binding complex, within infected cells.the role of the cap-binding complex, eif4f, in the translation of vaccinia virus mrnas has been analyzed within infected cells. plasmid dnas, which express dicistronic mrnas containing a picornavirus internal ribosome entry site, produced within vaccinia virus-infected cells both beta-glucuronidase and a cell surface-targeted single-chain antibody (sfv). cells expressing sfv were selected from nonexpressing cells, enabling analysis of protein synthesis specifically within the transfected cells. ...19989765426
conformational flexibility in a highly mobile protein loop of foot-and-mouth disease virus: distinct structural requirements for integrin and antibody binding.the g-h loop of foot-and-mouth disease virus vp1 protein is a highly mobile peptide, that extends from the capsid surface and that in native virions is invisible by x-ray crystallography. in serotype c, this segment contains a hypervariable region with several continuous, overlapping, b-cell epitopes that embrace the conserved arg-gly-asp (rgd) cell attachment motif. the solvent-exposed positioning of this peptide by selective insertion into different structural frameworks of e. coli beta-galact ...19989769208
a procedure for detecting selection in highly variable viral genomes: evidence of positive selection in antigenic regions of capsid protein vp1 of foot-and-mouth disease virus.a new procedure is described for the detection of positive selection among sequences of viral proteins from highly variable viruses. the approach is based on the estimation of the rates of nonsynonymous to synonymous (ns/s) mutations to the overall genetic distances amongst the sequences compared. rates of ns/s substitutions were calculated, and the individual profiles were arranged as a function of the genetic distance observed between the complete sequences. the resulting surfaces allowed iden ...19989779622
heterotypic recognition of recombinant fmdv proteins by bovine t-cells: the polymerase (p3dpol) as an immunodominant t-cell this study we have examined the recognition of vp0, vp1, vp2, vp3 and p3dpol by pbmc and cd4+ t-cells from infected, vaccinated-challenged, and multiply-vaccinated (o1, a24, c1 or asia1) cattle using recombinant proteins of an o1 serotype virus. the structural protein vp1 was recognised in an homotypic context whereas vp2, vp3, vp4 and p3dpol were also recognised by t-cells from animals exposed to heterotypic viruses. only the non-structural protein p3dpol was consistently recognised by t-cel ...19989783461
new generation of african horse sickness virus vaccines based on structural and molecular studies of the virus particles.african horse sickness virus (ahsv) is a member of the genus orbivirus, which also includes bluetongue virus (btv) and epizootic haemorrhagic disease (ehdv) virus. these orbiviruses have similar morphological and biochemical properties, with distinctive pathobiological properties and host ranges. sequencing studies of the capsid proteins have revealed evolutionary relationships between these viruses. biochemical studies of the viruses together with the expression of individual proteins and prote ...19989785506
rapid selection in modified bhk-21 cells of a foot-and-mouth disease virus variant showing alterations in cell tropism.with persistent foot-and-mouth disease virus (fmdv) in bhk-21 cells, there is coevolution of the cells and the resident virus; the virulence of the virus for the parental bhk-21 cells is gradually increased, and the cells become partially resistant to fmdv. here we report that variants of fmdv c3arg/85 were selected in a single infection of partially resistant bhk-21 cells (termed bhk-rb cells). indirect immunofluorescence showed that the bhk-rb cell population was heterogeneous with regard to s ...19989811758
distinct mechanisms of antibody-mediated enzymatic reactivation in beta-galactosidase molecular sensors.the antibody-mediated reactivation of engineered escherichia coli beta-galactosidases [benito et al. (1996) j. biol. chem. 271, 21251-21256] has been thoughtfully investigated in three recombinant molecular sensors. proteins m278vp1, jx772a and jx795a display the highly antigenic g-h loop peptide segment of foot-and-mouth disease virus vp1 protein, accommodated in different solvent-exposed loops of the assembled tetramer. these chimaeric enzymes exhibit a significant increase in enzymatic activi ...19989827559
structure of the foot-and-mouth disease virus leader protease: a papain-like fold adapted for self-processing and eif4g recognition.the leader protease of foot-and-mouth disease virus, as well as cleaving itself from the nascent viral polyprotein, disables host cell protein synthesis by specific proteolysis of a cellular protein: the eukaryotic initiation factor 4g (eif4g). the crystal structure of the leader protease presented here comprises a globular catalytic domain reminiscent of that of cysteine proteases of the papain superfamily, and a flexible c-terminal extension found intruding into the substrate-binding site of a ...19989857201
molecular cloning, expression and immunological analysis of the capsid precursor polypeptide (p1) from swine vesicular disease virus.swine vesicular disease virus (svdv) is the aetiological agent of a highly contagious viral disease of pigs, whose symptoms are indistinguishable from those caused by foot-and-mouth disease virus (fmdv). the gene coding for the capsid protein precursor of svdv (p1) from a recent spanish isolate (spa/1/'93) was cloned and expressed in bacteria, and the antigenicity and immunogenicity of the recombinant product were evaluated. the recombinant p1 was recognised by antibodies against svdv induced in ...19989870584
multiple molecular pathways for fitness recovery of an rna virus debilitated by operation of muller's ratchet.repeated bottleneck passages of rna viruses result in fitness losses due to accumulation of deleterious mutations. we have analysed the molecular events underlying fitness recovery of a highly debilitated foot- and-mouth disease virus (fmdv) clone, upon serial passage in bhk-21 cells. the debilitated clone included an unusual, internal polyadenylate extension preceding the second functional aug initiation codon, and a number of additional mutations scattered throughout the genome. comparison of ...19999878424
an rna virus can adapt to the multiplicity of infection.rna viruses evolve as complex distributions of mutants termed viral quasispecies. for this reason it is relevant to explore those environmental parameters that favour the selective advantage of some viral subpopulations over others. in the present study we provide direct evidence that the relative fitness of two competing viral subpopulations may depend on the multiplicity of infection (m.o.i.). two closely related subpopulations of foot-and-mouth disease virus (fmdv) of serotype c, which differ ...19989880011
two-helper rna system for production of recombinant semliki forest virus particles.alphavirus expression systems based on suicidal virus particles carrying recombinant replicons have proven to be a very efficient way to deliver genes for heterologous protein expression. however, present strategies for production of such particles have biosafety limitations due to the generation, by rna recombination, of replication-proficient viruses (rpvs). here we describe a new packaging system for semliki forest virus (sfv) based on a the use of a two-helper system in which the capsid and ...19999882310
solution structure of a retro-inverso peptide analogue mimicking the foot-and-mouth disease virus major antigenic site. structural basis for its antigenic cross-reactivity with the parent peptide.the antigenic activity of a 19-mer peptide corresponding to the major antigenic region of foot-and-mouth disease virus and its retro-enantiomeric analogue was found to be completely abolished when they were tested in a biosensor system in trifluoroethanol. this suggests that the folding pattern, which is alpha-helix in trifluoroethanol (confirmed by cd measurement), does not correspond to the biologically relevant conformation(s) recognized by antibodies. the nmr structures of both peptides were ...19999920919
the structure and function of a foot-and-mouth disease virus-oligosaccharide receptor complex.heparan sulfate has an important role in cell entry by foot-and-mouth disease virus (fmdv). we find that subtype o1 fmdv binds this glycosaminoglycan with a high affinity by immobilizing a specific highly abundant motif of sulfated sugars. the binding site is a shallow depression on the virion surface, located at the junction of the three major capsid proteins, vp1, vp2 and vp3. two pre-formed sulfate-binding sites control receptor specificity. residue 56 of vp3, an arginine in this virus, is cr ...19999927414
effect of mycobacterium sp. wall and avridine on the antibody response, igg isotype profile and proliferative response induced by foot and mouth disease virus (fmdv) vaccination in cattle.different immunomodulators have been previously tested in our laboratory as enhancers of the specific immune response to fmdv vaccines in a murine model [2-4]. here, we present results of two of these immunomodulators, a water-soluble fraction of the cell wall of mycobacterium sp. (wsf) and a synthetic lipoamide, avridine (av), which were tested in bovines included in fmdv oil vaccines. two different concentrations of inactivated viral antigen were employed and the effect of different concentrat ...19999987173
highly sensitive detection of swine vesicular disease virus based on a single tube rt-pcr system and dig-elisa detection.a highly sensitive detection of swine vesicular disease virus (svdv) based on a single tube rt-pcr system and digoxigenin (dig)-pcr-elisa detection was developed. using a one tube rt-pcr system, optimisation of the pcr conditions and optimisation of the microwell hybridisation and colourimetric detection of the amplicons resulted in a method that could detect viral rna in infected tissue culture fluid with a titre as low as 0.1 tcid50/100 microl. the same sensitivity was obtained with svdv-spike ...199910029329
low temperature and pressure stability of picornaviruses: implications for virus uncoating.the family picornaviridae includes several viruses of great economic and medical importance. poliovirus replicates in the human digestive tract, causing disease that may range in severity from a mild infection to a fatal paralysis. the human rhinovirus is the most important etiologic agent of the common cold in adults and children. foot-and-mouth disease virus (fmdv) causes one of the most economically important diseases in cattle. these viruses have in common a capsid structure composed of 60 c ...199910049311
flexibility of the major antigenic loop of foot-and-mouth disease virus bound to a fab fragment of a neutralising antibody: structure and neutralisation.the interaction of foot-and-mouth disease virus (fmdv) serotype c (clone c-s8c1) with a strongly neutralising monoclonal antibody (mab) 4c4 has been studied by combining data from cryoelectron microscopy and x-ray crystallography. the mab 4c4 binds to the exposed flexible gh-loop of viral protein 1 (vp1), which appears to retain its flexibility, allowing movement of the bound fab. this is in striking contrast to mab sd6, which binds to the same gh-loop of vp1 but exhibits no movement of the boun ...199910069951
induction of a protective antibody response to foot and mouth disease virus in mice following oral or parenteral immunization with alfalfa transgenic plants expressing the viral structural protein vp1.the utilization of transgenic plants expressing recombinant antigens to be used in the formulation of experimental immunogens has been recently communicated. we report here the development of transgenic plants of alfalfa expressing the structural protein vp1 of foot and mouth disease virus (fmdv). the presence of the transgenes in the plants was confirmed by pcr and their specific transcription was demonstrated by rt-pcr. mice parenterally immunized using leaf extracts or receiving in their diet ...199910069960
noncytopathic flavivirus replicon rna-based system for expression and delivery of heterologous genes.noncytopathic replicons of the flavivirus kunjin (kun) were employed for expression and delivery of heterologous genes. replicon vector c20dx2arep, containing a unique cloning site followed by the sequence of 2a autoprotease of foot-and-mouth disease virus, was constructed and used for expression of a number of heterologous genes including chloramphenicol acetyltransferase (cat), green fluorescent protein (gfp), beta-galactosidase, glycoprotein g of vesicular stomatitis virus, and the core and n ...199910069962
[synthesis and immunogenic properties of peptides--fragments of the immunodominant regions of the vp1 protein of the asia-1 type of foot- and-mouth disease virus].potential immunodominant epitopes were predicted on the basis of a theoretical analysis of the antigenic structure of the vp1 protein of the type asia-1 foot-and-mouth disease virus. peptides corresponding to the 140-153, 136-153, 132-153, 143-157, 137-157, and 193-208 fragments of the vp1 protein sequence were synthesized by the solid phase method, and the immunogenic properties of the peptides were studied on guinea pigs. the shortest peptide exhibiting the protective effect was found to corre ...199810079947
demonstration of bovine cd8+ t-cell responses to foot-and-mouth disease virus.the aim of this study was to investigate the importance of cellular immunity in foot-and-mouth disease in cattle, in particular to determine whether a cd8+ t-cell response could be detected, as these cells may play a role in both immunity and virus persistence. as attempts to characterize classical cytotoxic t cells had yielded non-reproducible results, largely due to high backgrounds in control cultures, a proliferation assay was developed that was demonstrated to detect antigen-specific, mhc c ...199910092006
evidence of partial protection against foot-and-mouth disease in cattle immunized with a recombinant adenovirus vector expressing the precursor polypeptide (p1) of foot-and-mouth disease virus capsid proteins.a recombinant live vector vaccine was produced by insertion of cdna encoding the structural proteins (p1) of foot-and-mouth disease virus (fmdv) into a replication-competent human adenovirus type 5 vaccine strain (ad5 wt). groups of cattle (n = 3) were immunized twice, by the subcutaneous and/or intranasal routes, with either the ad5 wt vaccine or with the recombinant fmdv ad5-p1 vaccine. all animals were challenged by intranasal instillation of fmdv 4 weeks after the second immunizations. in th ...199910092007
development and characterization of monoclonal antibodies to foot and mouth disease virus type 'c'.five fusion experiments were conducted with spleen cells from balb/c mice immunized with purified 146s antigen of foot and mouth disease virus type 'c' (vaccine strain). monoclones (31) thus developed were isotyped as igm (3), igg1 (6), igg2a (5), igg2b (3) and igg3 (14). eleven clones isotyped as igm, igg2a and igg2b showed neutralizing activity in virus neutralization and plaque reduction tests. six of the neutralizing clones precipitated 146s virus in ouchterlony reaction. on the basis of loc ...199810093509
a cell adhesion peptide from foot-and-mouth disease virus can direct cell targeted delivery of a functional enzyme.the g-h loop of foot-and-mouth disease virus is a disordered protrusion of the vp1 protein exposed on the virion surface. this short stretch includes an arginine-glycine-aspartic acid tripeptide, a recognized integrin-binding motif, which is responsible for cell attachment and infection. eight copies of a peptide reproducing the amino acid sequence of this fmdv ligand have been displayed in solvent-exposed regions on an enzymatically active recombinant beta-galactosidase. this viral peptide segm ...199810099340
a comparative study of cyclization strategies applied to the synthesis of head-to-tail cyclic analogs of a viral epitope.a family of head-to-tail cyclic peptide models of the antigenic site a (g-h loop of viral protein 1) of foot-and-mouth disease virus has been designed on the basis of the three-dimensional structure adopted by the linear peptide ytasargdlahlttt upon binding to neutralizing monoclonal antibodies. three different methods of cyclization have been examined to access the peptides. solution cyclization of a minimally protected linear precursor provided the expected products but required several purifi ...199910195442
self-processing 2a-polyproteins--a system for co-ordinate expression of multiple proteins in transgenic plants.achieving co-ordinate, high-level and stable expression of multiple transgenes in plants is currently difficult. expression levels are notoriously variable and influenced by factors that act independently on transgenes at different genetic loci. instability of expression due to loss, re-arrangement or silencing of transgenes may occur, and is exacerbated by increasing numbers of transgenic loci and repeated use of homologous sequences. even linking two or more genes within a t-dna does not neces ...199910205902
production of interleukin-12 as a self-processing 2a polypeptide.interleukin-12 (il-12) is a heterodimeric cytokine composed of two disulfide-linked subunits (p40 and p35) encoded by separate genes. we used the apparent autocleavage property of a 2a peptide from the foot-and-mouth disease virus (fmdv) to express bovine (bo) il-12 as a self-processing polypeptide (p402ap35). we demonstrate that 2a will mediate the cleavage of p402ap35 into two separate subunits in a manner similar to that observed during the processing of the fmdv polypeptide. furthermore, thi ...199910213462
emergency vaccination of sheep against foot-and-mouth disease: protection against disease and reduction in contact transmission.the ability of several emergency fmd vaccine formulations to elicit early protective immunity in sheep was examined. all vaccine formulations were shown to protect sheep against airborne challenge with homologous fmdv within 4 days of vaccination. protection was associated in part with the induction of serum antibody responses but was also demonstrated in the absence of any detectable antibody response at the time of challenge. aqueous al(oh)3/saponin vaccine formulations and oil emulsion vaccin ...199910217583
comparative organization and function of the major histocompatibility complex of domesticated cattle.this review focuses on recent advances in research on the bovine major histocompatibility complex (bola), with specific reference to the genetic organization, polymorphism and function of the class ii genes. the bola region is unlike the mhc of humans and mice in that a large inversion has moved several class ii genes, including the tap/lmp cluster, close to the centromere of bovine chromosome 23. therefore, close linkage of mhc genes and other genes associated with the mhc in humans and mice do ...199910319257
evidence for the persistence of foot-and-mouth disease virus in pigs. 199910328832
recombinant fusion protein and dna vaccines against foot and mouth disease virus infection in guinea pig and this study, we provide evidence that a recombinant fusion protein containing beta-galactosidase and a tandem repeat peptide of immunogenic dominant epitope of foot-and-mouth disease virus (fmdv) vp1 protein elicits high levels of neutralizing antibody and protects both guinea pigs and swine against infection. vaccination with this fusion protein induced a fmdv-specific proliferative t-cell response and a neutralizing antibody response. the immunized guinea pigs and swine were protected agains ...199910333237
serological survey of viral antibodies in llamas (lama glama) in argentina.this study analysed sera from 390 llamas (lama glama) from nine farms located in three different argentine provinces: buenos aires, cordoba and jujuy. the samples were tested for antibodies against 8 virus known to infect cattle: bovine herpesvirus type 1 (bhv-1), bovine viral diarrhea virus (bvdv), bovine adenovirus (badv iii), bovine enterovirus (bev), bovine rotavirus (brv), bluetongue virus (btv), bovine leukaemia virus (blv), and foot-and-mouth virus (fmdv) by conventional methods such as s ...199910337237
interaction of eukaryotic initiation factor eif4b with the internal ribosome entry site of foot-and-mouth disease virus is independent of the polypyrimidine tract-binding protein.eukaryotic translation initiation factor 4b (eif4b) binds directly to the internal ribosome entry site (ires) of foot-and-mouth disease virus (fmdv). mutations in all three subdomains of the ires stem-loop 4 reduce binding of eif4b and translation efficiency in parallel, indicating that eif4b is functionally involved in fmdv translation initiation. in reticulocyte lysate devoid of polypyrimidine tract-binding protein (ptb), eif4b still bound well to the wild-type ires, even after removal of the ...199910364367
recombinant viruses expressing the foot-and-mouth disease virus capsid precursor polypeptide (p1) induce cellular but not humoral antiviral immunity and partial protection in pigs.the importance of the induction of virus neutralizing antibodies to provide protection against foot-and-mouth disease virus (fmdv) infection is well established. however, recent studies with recombinant adenovirus expressing the precursor polypeptide of the viral capsid (p1) indicate that cattle inoculated with this recombinant vector developed partial protection against fmdv infection, in the absence of a detectable specific humoral response. other viral vectors have been widely used to induce ...199910364496
the properties of chimeric picornavirus ireses show that discrimination between internal translation initiation sites is influenced by the identity of the ires and not just the context of the aug codon.the internal ribosome entry segment (ires) of picornaviruses consists of approximately 450 nt of 5'-untranslated region, terminating at the 3' end with an approximately 25 nt element consisting of an absolutely conserved uuuc motif followed by a more variable pyrimidine-rich tract and g-poor spacer, and finally an aug triplet, which is considered to be the actual ribosome entry site. events following entry at this site differ among picornaviruses: in encephalomyocarditis virus (emcv) virtually a ...199910376876
serotyping of foot-and-mouth disease virus by antigen capture reverse transcriptase/polymerase chain reaction.the technique of capturing of foot-and-mouth disease virus (fmdv) from clinical material in microcentrifuge tubes coated with type-specific antibodies and amplifying the viral sequences by rt/pcr in the same tube, promoted the detection and serotyping of fmdv with high sensitivity and specificity. the efficiency of antigen capturing and shelf life of the coated tubes was improved by glutaraldehyde fixation of antibodies to the tubes. virus in infected tissues, even after storage for 25-30 years ...199910403675
capsid protein-encoding (p1) sequence of foot and mouth disease virus type asia 1 ind 63/72.variations in the amino acid sequence of foot-and-mouth disease virus (fmdv) structural proteins are the basis for the antigenic diversity of the virus. majority of antigenic sites for the virus neutralization are present on vp1, the major immunogenic protein. however, a few conformational epitopes are present on the structural proteins vp2 and vp3. the nucleotide sequence encoding all the four structural proteins (p1 region) of fmdv type asia 1 ind 63/72 was determined. the nucleotide and the d ...199910403702
efficient inactivation of viruses and mycoplasma in animal sera using uvc irradiation.transmission of viruses by animal sera represents a considerable risk for humans and animals particularly when the serum is used for the production of pharmaceutical products such as vaccines. procedures applicable for inactivating large numbers of different viruses, both enveloped and non-enveloped, are therefore mandatory. for this purpose we have developed and validated uvc irradiation as the virus-inactivation procedure of choice for serum to be used in an industrial setting. spiking experim ...199910404882
a universal virus inactivant for decontaminating blood and biopharmaceutical products.removal of virus infectivity from blood and biopharmaceutical products prepared from blood is an issue of considerable importance. irrespective of the methods that are chosen it is vital that the biological activity of the product is not impaired. for blood and unfractionated plasma or serum, the problem is even more challenging. selective inactivation of the genome is the key step in the preparation of killed virus vaccines. imines have been used for more than 30 years for the preparation of in ...199910404883
chaperonin 10 of mycobacterium tuberculosis induces a protective immune response to foot-and-mouth disease virus.chaperonin 10 of m. tuberculosis conferred partial or total protection against generalized foot-and-mouth disease (fmd) in guinea-pigs challenged with o1 lausanne fmd virus. chaperonin 10-immunized animals mounted an antibody response to the protein, one epitope of which was found in the c-terminal half. a similar recognition pattern was observed in fmd-convalescent guinea-pigs, swine and cattle. anti-chaperonin 10 sera showed antiviral activity against fmdv-infected bhk-21 cells. there was stro ...199910416374
use of the 2a sequence from foot-and-mouth disease virus in the generation of retroviral vectors for gene therapy.we describe the construction of retroviral plasmid vectors in which two genes are linked by a minimum of 96 nucleotides encoding the 2a sequence from the picornavirus foot-and-mouth disease virus (fmdv). transcription and translation gives rise to a bicistronic mrna and two independent protein products. the system offers advantages to other alternative ways to create polycistronic mrnas and can be used in gene therapy delivery vectors.199910435104
protection of swine from foot-and-mouth disease with one dose of an all-d retro peptide.nine pigs were given a single inoculum of 100 microg of the all-d retro peptide corresponding to the immunodominant gh loop encompassing residues 141-159 of capsid protein vp1 of foot-and-mouth disease virus serotype a, sub-type 12. the peptide was conjugated to activated keyhole limpet haemocyanin and oil-adjuvanted before inoculation. the animals were challenged eleven weeks post-vaccination by exposing them to a pig which had been infected with the virus by inoculation. two naive animals were ...199910438060
translation initiation factor eif4b interacts with a picornavirus internal ribosome entry site in both 48s and 80s initiation complexes independently of initiator aug location.most eukaryotic initiation factors (eifs) are required for internal translation initiation at the internal ribosome entry site (ires) of picornaviruses. eif4b is incorporated into ribosomal 48s initiation complexes with the ires rna of foot-and-mouth disease virus (fmdv). in contrast to the weak interaction of eif4b with capped cellular mrnas and its release upon entry of the ribosomal 60s subunit, eif4b remains tightly associated with the fmdv ires during formation of complete 80s ribosomes. bi ...199910438840
rapidity of specific antibody-antigen interactions.analysis of humoral immune responses against viruses has concentrated on studies with serum dilutions, which reflect characteristics pertaining to the diluent buffer but not the serum environment. the majority of virus-specific antibody in serum from foot-and-mouth disease virus (fmdv)-vaccinated cattle bound to antigen within 10-60 s, whereas aspecific reactions evolved more slowly. upon dilution of sera, the reaction characteristics no longer related to those obtained with the serum, particula ...199910447921
differentiation of convalescent animals from those vaccinated against foot-and-mouth disease by a peptide elisa.we have identified continuous antigenic determinants within the amino acid sequences of the conserved nonstructural region containing proteins 2c and 3abc of foot-and-mouth disease virus which can distinguish between the sera from vaccinated and infected animals. an elisa based on a 3b peptide gave a positive reaction with sera from cattle, pigs, sheep and guinea pigs infected with all seven serotypes of the virus, but not with sera from vaccinated animals. in experiments with cattle and pigs to ...199910462239
antigenic properties and population stability of a foot-and-mouth disease virus with an altered arg-gly-asp receptor-recognition motif.the antigenic properties and genetic stability of a multiply passaged foot-and-mouth disease virus (fmdv) clone c-s8c1 with an arg-gly-gly triplet (rgg) instead of the arg-gly-asp (rgd) integrin-recognition motif at positions 141 to 143 of capsid protein vp1 are described. clear antigenic differences between fmdv rgg and clone c-s8c1 have been documented in elisa, enzyme-linked immunoelectrotransfer (western) blot and neutralization assays using site a-specific monoclonal antibodies and anti-fmd ...199910466785
evidence for the role of his-142 of protein 1c in the acid-induced disassembly of foot-and-mouth disease virus capsids.foot-and-mouth disease virus (fmdv) capsids are inherently labile under mildly acidic conditions, dissociating to pentamers at ph values in the region of 6.5, with the release of protein 1a and the viral rna. this acid-induced disassembly is thought to be required for the entry of the virus genome into the host cell. previous work has highlighted a histidine-alpha-helix charge-dipole interaction at the twofold axes of symmetry between pentamers and has suggested that this interaction plays a rol ...199910466786
expression in cattle of epitopes of a heterologous virus using a recombinant rinderpest virus.we have investigated the bovine immune response to heterologous proteins expressed using a recombinant rinderpest virus (rpv). a new gene unit was created in a cdna copy of the genome of the vaccine strain of rpv, and an open reading frame inserted that encodes the polymerase (3dpol) and parts of the capsid protein vp1 from foot-and-mouth disease virus (fmdv). infectious recombinant rpv was rescued and shown to express the fmdv-derived protein at good levels in infected cells. the rescued virus ...199910466801
design and construction of african swine fever virus chimeras incorporating foreign viral the present work we have studied the feasibility of introducing foreign epitopes into the african swine fever virus (asfv) particle by genetic manipulation of the virus. for this purpose, we developed specific transfer vectors containing the gene encoding for the highly antigenic structural asfv protein p54 in which foreign sequences were introduced. dna sequences encoding continuous linear epitopes, the antigenic site a from foot-and-mouth disease virus (fmdv) vp1 protein and the da3 antigen ...199910481737
development of dna vaccines for foot-and-mouth disease, evaluation of vaccines encoding replicating and non-replicating nucleic acids in swine.we have developed naked dna vaccine candidates for foot-and-mouth disease (fmd), an important disease of domestic animals. the virus that causes this disease, fmdv, is a member of the picornavirus family, which includes many important human pathogens, such as poliovirus, hepatitis a virus, and rhinovirus. picornaviruses are characterized by a small (7-9000 nucleotide) rna genome that encodes capsid proteins, processing proteinases, and enzymes required for rna replication. we have developed two ...199910486933
immuno affinity purification of foot and mouth disease virus type specific antibodies using recombinant protein adsorbed to polystyrene wells.the specificity of foot and mouth disease virus (fmdv) serological tests depends largely on the quality and purity of the antibodies used. such type specific antibodies can be generated by hybridoma technology. alternatively, the specific antibodies can be selected from polyclonal serum by immunoaffinity chromatography using recombinant protein/peptide bound affinity matrices. based on this approach, we purified selectively antibodies against the major epitopes of vp 1 of fmdv serotype asia 1 us ...199910488757
improvement of the immune response to foot and mouth disease virus vaccine in calves by using avridine as adjuvant.the epidemiological analysis of the cattle population during the eradication plan of foot and mouth disease (fmd) in argentina clearly indicated a higher incidence of the disease in animals within their first year of age. it is important to improve the efficacy of the vaccination in those animals. in a previous report, we have shown the effect of an immunomodulator, avridine (avr), in the enhancement of the immune response elicited by fmd virus (fmdv) vaccines in experimental hosts [berinstein, ...199910490231
[progress in developing viral polynucleotide (dna) vaccines].reviews published reports on the progress in development of dna vaccines protecting from viral diseases. emphasizes the advantages of the preparation injection into the epidermis and the possibility of stimulating the immunogenicity of dna vaccines with adjuvants and cytokines. discusses the results of studies on the immunogenicity of dna vaccines from human, simian, and feline immunodeficiency viruses, hepatitis b and c viruses, herpes simplex virus, cytomegalovirus, influenza and measles virus ...199910500980
delineation of a neutralizing subregion within the immunodominant epitope (gh loop) of foot-and-mouth disease virus vp1 which does not contain the rgd motif.the major immunogenic site of foot-and-mouth disease virus (fmdv) is contained in a disordered loop comprising residues 134-158 of capsid protein vp1, located on the surface of the viral particle. peptides corresponding to this sequence generally elicit protective levels of neutralizing antibodies in guinea pigs. in some instances, however, the level of neutralizing antibodies is low although the level of antibodies against the peptide, determined by elisa, is as high as that in the sera with hi ...199910501234
surface plasmon resonance screening of synthetic peptides mimicking the immunodominant region of c-s8c1 foot-and-mouth disease virus.the main antigenic site (site a) of foot-and-mouth disease virus (fmdv, strain c-s8c1) may be adequately reproduced by a 15-peptide with the amino acid sequence h-ytasargdlahlttt-nh(2) (a15), corresponding to the residues 136-150 of the viral protein vp1. the effect of amino acid substitutions within a15 on its antigenicity towards monoclonal antibodies (mab) raised against antigenic site a, has been studied by means of biacore technology, based on surface plasmon resonance (spr). although these ...199910506663
rhinovirus 2a proteinase mediated stimulation of rhinovirus rna translation is additive to the stimulation effected by cellular rna binding proteins.the internal ribosome entry site (ires) of enteroviruses, and especially human rhinoviruses (hrv), functions very inefficiently in rabbit reticulocyte lysates, but can be stimulated by addition of hela cell extracts. two hela cell activities have been identified: the a-type activity is due to polypyrimidine tract binding protein and the b-type to unr. in addition hrv and enterovirus ires function requires a third rna binding protein, poly(rc) binding protein 2, but this is present in reticulocyt ...199910507322
the structures of picornaviral proteinases.picornaviruses are a family of positive-strand rna viruses the members of which include poliovirus, hepatitis a virus, rhinovirus, foot-and-mouth disease virus and encephalomyocarditis virus. the genetic information contained in the single-stranded, positive sense rna genome is expressed as a single protein of around 2000 amino acids. this primary product of protein synthesis, designated the polyprotein, is subsequently cleaved into the mature viral proteins by proteinases present within it. the ...199910507325
biochemical and structural studies with neutralizing antibodies raised against foot-and-mouth disease virus.the function of a loop exposed on the aphthovirus capsid (the g-h loop of protein vp1) has been explored by combining genetic and structural studies with viral mutants. the loop displays a dual function of receptor recognition and interaction with neutralizing antibodies. remarkably, some amino acid residues play a critical role in both such disparate functions. therefore residues subjected to antibody pressure for variation may nevertheless maintain a role in receptor recognition for which inva ...199910507326
localization of foot-and-mouth disease virus rna by in situ hybridization within bovine tissues.foot-and-mouth disease is a highly contagious disease of cloven hooved animals. in cattle, both acute and long-term persistent infections occur. foot-and-mouth disease virus (fmdv), a picornavirus, has been shown, using virus isolation procedures, to replicate in the pharynx and soft palate of cattle. in this study, in situ hybridization has been used to detect fmdv rna within the cells of tissues removed from infected bovines. a digoxigenin-labelled anti-sense rna probe was prepared correspondi ...199910513288
genomic nucleotide sequence of a foot-and-mouth disease virus clone and its persistent derivatives. implications for the evolution of viral quasispecies during a persistent infection.the consensus nucleotide sequence of the entire genome of foot-and-mouth disease virus (fmdv) (biological clone c-s8c1) has been completed, and compared with that of two persistent derivatives r99 and r146, rescued after 99 and 146 passages of the carrier bhk-21 cells. consensus sequences were determined directly from supernatants of persistently infected cells, without intervening cytolytic amplification of the viruses. these genomic sequences have also been compared with that of fmdv r100, a v ...199910518712
protective immune response to 16 kda immunoreactive recombinant protein encoding the c-terminal vp1 portion of foot and mouth disease virus type asia 1.recombinant protein of foot and mouth disease virus (fmdv) type asia 1 corresponding to the c-terminal half of vp1 was expressed in escherichia coli. as an alternative to the synthetic peptide, this selected c-terminal region was used as a protein vaccine in guinea pigs in order to study the immune response with various adjuvant formulations: immune stimulatory complexes (iscoms), montanide isa 206, freund's incomplete adjuvant (fia), lipopolysaccharide (lps) and cytokine mixture. a primary dose ...199910524794
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