TitleAbstractYear(sorted ascending)
recent advances in bovine vaccine technology.a description of new commercial and experimental vaccines for viral and bacterial diseases of cattle can be broadly divided into those used for both beef and dairy cows and those used predominantly in dairy cattle. for both types of cattle, newer and experimental vaccines are directed against several of the important viral (e.g., bovine herpesvirus 1, bovine viral diarrhea virus, bovine respiratory syncytial virus, parainfluenza type 3, and foot-and-mouth disease virus) and bacterial pathogens ( ...19938408872
molecular epidemiology of foot-and-mouth disease virus type o.a phylogenetic tree based on the vpi sequences of type o foot-and-mouth disease virus (fmdv) has been derived. direct sequencing of pcr products has been used to obtain the vp1 gene sequences of new isolates. the tree exhibits four main lineages that largely correlate with the geographical origin of isolates. the analysis supports a close relationship between european o1 field isolates and vaccine strains, with the exception of o thalheim aus/81 and o wuppertal ger/82 which were probably of non- ...19938409952
dilute passage promotes expression of genetic and phenotypic variants of human immunodeficiency virus type 1 in cell culture.we have studied the extent of genetic and phenotypic diversification of human immunodeficiency virus type 1 (hiv-1) upon 15 serial passages of clonal viral populations in mt-4 cell cultures. several genetic and phenotypic modifications previously noted during evolution of hiv-1 in infected humans were also observed upon passages of the virus in cell culture. notably, the transition from non-syncytium-inducing to syncytium-inducing phenotype (previously observed during disease progression) and fi ...19938474182
characterization of the foot-and-mouth disease virus 3c protease expressed in escherichia coli.we have constructed a clone encoding the foot-and-mouth disease virus (fmdv) 3c protease gene (p3c) using the polymerase chain reaction. the construct was engineered to contain initiation and termination codons and cloned into a plasmid under the control of the bacteriophage t7 promoter. the p3c gene was expressed both in an in vitro transcription-translation system and in vivo in an escherichia coli system containing an inducible t7 rna polymerase gene. in both systems the expressed products we ...19938212567
split decomposition: a technique to analyze viral evolution.a clustering technique allowing a restricted amount of overlapping and based on an abstract theory of coherent decompositions of finite metrics is used to analyze the evolution of foot-and-mouth disease viruses. the emerging picture is compatible with the existence of viral populations with a quasispecies structure and illustrates various forms of evolution of this virus family. in addition, it allows the correlation of these forms with geographic occurrence.19938234292
transient inhibition of foot-and-mouth disease virus infection of bhk-21 cells by antisense oligonucleotides directed against the second functional initiator aug.the antiviral activity of antisense oligonucleotides corresponding to different regions of foot-and-mouth disease virus (fmdv) genome has been assessed in bhk-21 cells. the locations of the oligonucleotides used were: (i) two regions within the internal ribosome entry site (ires), involved in the regulation of the translation initiation of the viral polyprotein; (ii) each of the two functional initiator augs; (iii) an internal sequence of p2a gene; and (iv) a region at the 3' end non-coding regi ...19938250540
co-replication of several isotypes of foot-and-mouth disease virus.genome segments of the foot-and-mouth disease virus isolates o1lombardy and o3 venezuela that encode, among other products, capsid protein vp1 were amplified using pcr, and the products were cloned and sequenced. the alignment of up to 11 o3-specific sequences revealed six silent nucleotide changes a well as six changes that cause amino acid substitutions in capsid protein vp1 at positions 45, 83, 141, 145, 170 and 178. the heterogeneity of three o1-specific sequences consisted of seven silent e ...19938277282
viral antibodies in bovine fetuses in order to establish the prevalence of viral infections of the bovine fetus in argentina, a serological survey for antibodies against viral agents currently affecting cattle in this country was conducted. antibodies against foot-and-mouth disease virus (fmdv), bovine herpesvirus-1 (bhv-1), bovine leukaemia virus (blv), bovine rotavirus (brv), bovine coronavirus (bcv), bovine viral diarrhoea virus (bvdv) and parainfluenza-3 (pi-3) were investigated in a total of 315 fetal serum samples. conventi ...19938284507
effects of different continium dielectric models in a molecular dynamics and energy minimization study of the antigenic loop of foot-and-mouth disease virus.this study presents the influence of the dielectric constant on the final structure of the major antigenic loop of the fmdv serotype c. minimizations have been performed on the nine-residue peptide ac-tasargdla-nhme, using two expressions for the dielectric constant: a distance-independent (epsilon = kappa), and a distance-dependent (epsilon = kappa *r) forms, and for kappa values from 1 to 10. in addition, kappa = 40 and 80 has also been considered for the constant expression of the dielectrics ...19938286066
genotypic and phenotypic changes of bhk-21 cells grown in suspension cultures.the propagation of foot-and-mouth disease virus on bhk-21 suspension cells, although economically convenient, may yield a scarcely immunizing antigen. helpful insights were obtained by investigating a few genotypic and phenotypic features of the cell cultures. the appearance of polyploid populations, higher cell concentrations at the end of culturing, the progressive reduction of spreading on surfaces and an abnormal expression of the α5β1 integrin were found to be correlated with the number of ...199322358669
trans complementation by rna of defective foot-and-mouth disease virus internal ribosome entry site elements.a region of about 435 bases from the 5' noncoding region of foot-and-mouth disease virus rna directs internal initiation of protein synthesis. this region, termed the internal ribosome entry site (ires), is predicted to contain extensive secondary structure. precise deletion of five predicted secondary structure features has been performed. the mutant ires elements have been constructed into vectors which express bicistronic mrnas and assayed within cells. each of the modified ires elements was ...19948289373
foot-and-mouth disease virus particles contain replicase protein antibody against the escherichia coli-expressed rna polymerase of foot-and-mouth disease virus (fmdv) reacts with the virus in elisa and radioimmunoprecipitation experiments and with a protein of the disrupted virus particle in an immunoblot analysis. treatment of the virus with trypsin, which cleaves capsid protein vp1 and a 56-kda polypeptide present in trace amount in the particles, reduces the level of the reaction in elisa and radioimmunoprecipitation and eliminates the immunoblot reacti ...19948290591
function of minor polypeptides in foot-and-mouth disease virus and poliovirus.foot-and-mouth disease virus and poliovirus each contain several minor polypeptides, in addition to the four structural proteins. one of these, the viral rna polymerase, can also act as a nuclease, hydrolysing the rna and thus destroying viral infectivity. it is tightly bound to the rna and may be the packaging signal for assembly of the particle.19947889327
t-lymphocyte responses in guinea pigs vaccinated with foot-and-mouth disease virus.the guinea pig provides an alternative experimental model for analysis of the immune response against foot-and-mouth disease virus (fmdv). the cellular immune response against fmdv in this experimental animal is unknown and was analyzed by in vivo and in vitro studies. in guinea pigs immunized with an fmdv a5 vaccine, a marked change in t-lymphocyte count appeared. for analyzing which functional t-cell compartment was affected, immunofluorescence studies, using monoclonal antibodies directed aga ...19947909182
specific inhibition of aphthovirus infection by rnas transcribed from both the 5' and the 3' noncoding regions.rna molecules containing the 3' terminal region of foot-and-mouth disease virus (fmdv) rna in both antisense and sense orientations were able to inhibit viral fmdv translation and infective particle formation in bhk-21 cells following comicroinjection or cotransfection with infectious viral rna. antisense, but not sense, transcripts from the 5' noncoding region including the proximal element of the internal ribosome entry site and the two functional initiation augs were also inhibitory, both in ...19947933126
antigenic heterogeneity of a foot-and-mouth disease virus serotype in the field is mediated by very limited sequence variation at several antigenic sites.antigenic variation in a major discontinuous site (site d) of foot-and-mouth disease virus (fmdv) of serotype c has been evaluated with neutralizing monoclonal antibodies. isolates representing the major evolutionary sublines previously defined for serotype c were compared. extensive variation, comparable to that of continuous epitopes within the hypervariable immunodominant site a (the vp1 g-h loop), was found. the amino acid sequences of the complete capsids of three antigenically highly diver ...19948107204
foot-and-mouth disease virus 2a oligopeptide mediated cleavage of an artificial polyprotein.we describe the construction of a plasmid (pcat2agus) encoding a polyprotein in which a 19 amino acid sequence spanning the 2a region of the foot-and-mouth disease virus (fmdv) polyprotein was inserted between the reporter genes chloramphenicol acetyl transferase (cat) and beta-glucuronidase (gus) maintaining a single, long open reading frame. analysis of translation reactions programmed by this construct showed that the inserted fmdv sequence functioned in a manner similar to that observed in f ...19948112307
analysis of mixed foot-and-mouth disease virus infections in saudi arabia: prolonged circulation of an exotic serotype.plaque purification of foot-and-mouth disease (fmd) type o viruses isolated from cattle in saudi arabia showed the presence of mixed serotype infections. sixteen out of 31 samples collected between 1985 and 1991 also contained asia 1 virus, a serotype which had previously only been isolated from a single outbreak in that country in 1980. nucleotide sequences of the asia 1 component of all these samples revealed little variation and showed that they were closely related to both a russian lapinize ...19948119359
genetic relationships between foot-and-mouth disease type asia 1 viruses.the sequence of 165 nucleotides at the 3' end of the 1d (vp1) gene of foot-and-mouth disease (fmd) virus was determined for 44 type asia 1 strains isolated from throughout asia between 1954-92. analysis of the relationships between the virus genomes showed epidemiological links not previously evident. the possible origin of the only outbreak of fmd asia 1 to have occurred in europe, in greece in 1984, was identified because the nucleotide sequence of this virus was closely-related to the sequenc ...19948119360
rgd sequence of foot-and-mouth disease virus is essential for infecting cells via the natural receptor but can be bypassed by an antibody-dependent enhancement pathway.foot-and-mouth disease virus appears to initiate infection by binding to cells at an arg-gly-asp (rgd) sequence found in the flexible beta g-beta h loop of the viral capsid protein vp1. the role of the rgd sequence in attachment of virus to cells was tested by using synthetic full-length viral rnas mutated within or near the rgd sequence. baby hamster kidney (bhk) cells transfected with three different rnas carrying mutations bordering the rgd sequence produced infectious viruses with wild-type ...19948127909
a rapid and sensitive chemiluminescence dot-immunobinding assay for screening hybridoma supernatants.the present report describes a simple and rapid dot-immunobinding assay combined with a chemiluminescence detection system for screening hybridoma supernatants for specific monoclonal antibodies (mabs). small rectangular nitrocellulose filters dotted with either crude mixtures of antigens, or with control samples, were placed in six well plates, incubated with hybridoma supernatants, then stained with peroxidase-conjugated anti-mouse igg. the reaction was performed with a chemiluminescence detec ...19948157996
crystallization and preliminary x-ray diffraction studies of a monoclonal antibody fab fragment against foot-and-mouth disease virus and of its complex with the main antigenic site peptide.the fab fragment of the neutralizing monoclonal antibody sd6 elicited against foot-and-mouth disease virus (fmdv) c-s8c1 and its complex with a peptide, corresponding to the major antigenic site of fmdv (vp1 residues 136-150, ytasargdlahlttt), have been crystallized using the hanging drop vapor diffusion techniques. for the isolated fab, crystals diffracting to 2.5 a resolution were obtained at room temperature using ammonium sulfate as precipitant. these crystals are monoclinic, space group c2, ...19948159669
picornaviral 3c cysteine proteinases have a fold similar to chymotrypsin-like serine proteinases.the picornavirus family includes several pathogens such as poliovirus, rhinovirus (the major cause of the common cold), hepatitis a virus and the foot-and-mouth disease virus. picornaviral proteins are expressed by direct translation of the genomic rna into a single, large polyprotein precursor. proteolysis of the viral polyprotein into the mature proteins is assured by the viral 3c enzymes, which are cysteine proteinases. here we report the x-ray crystal structure at 2.3 a resolution of the 3c ...19948164744
rapid cell variation can determine the establishment of a persistent viral infection.evidence for a mechanism of initiation of viral persistence in which the cell, and not the virus, plays a critical role has been obtained using the important animal pathogen foot-and-mouth disease virus (fmdv). we have developed a virulence assay consisting of quantification of the ability of virus to kill cells and of cells to divide in the presence of virus and to initiate a carrier state. cells were cured of fmdv at early times following a cytolytic infection of bhk-21 monolayers with fmdv. w ...19948170973
experimental transmission of foot-and-mouth disease virus from carrier african buffalo (syncerus caffer) to cattle in zimbabwe.four female cattle and three male african buffalo (syncerus caffer) which were free of foot-and-mouth disease (fmd) virus were held together on an island in lake kariba, zimbabwe. the buffalo were experimentally infected with fmd virus type sat2, developed generalised disease and became virus carriers. while the buffalo were in the acute phase of the disease the susceptible contact cattle did not show lesions, no virus was recovered from them and they did not develop serum antibodies. however, f ...19948171808
recognition of b and t cell epitopes by cattle immunized with a synthetic peptide containing the major immunogenic site of vp1 fmdv 01 campos.the precise location of b and t cell epitopes have been established in a peptide containing the major immunogenic site (residues 135-160) of fmdv strain 01 campos (01c) vp1. the peptide (p135-160), administered free or conjugated to bovine serum albumin, induced complete protection in guinea pigs and a strong neutralizing antibody (nab) response in cattle. using a set of partially overlapping peptides it was shown that although several b cell epitopes were distributed along the p135-160, the res ...19948184548
natural transmission of foot-and-mouth disease virus from african buffalo (syncerus caffer) to cattle in a wildlife area of outbreak of foot-and-mouth disease (fmd) occurred during april 1991 in a trypanosomiasis sentinel cattle herd by the rifa river to the east of lake kariba, zimbabwe. despite the cattle having been vaccinated biannually for the previous five years the disease was severe. the viruses isolated from the affected animals were typed as fmd virus type sat 1. free-living african buffalo (syncerus caffer) which had been using the same watering place as the affected cattle were sampled and fmd type sat ...19948197679
antibody response to 146s particle, 12s protein subunit and isolated vp1 polypeptide of foot-and-mouth disease virus type asia-1.the antibody response to foot-and-mouth disease virus (fmdv) antigens of type asia-1 in guinea-pigs was studied by micro-serum neutralization test (msnt) and enzyme-linked immunosorbent assay (elisa). one inoculation of as little as 1 microgram of binary ethyleneimine (bei)-inactivated 146s virus particles in guinea-pigs elicited enough neutralizing antibodies to protect them against challenge with virulent virus. however, one inoculation of live 146s virus particles elicited higher levels of ne ...19948203119
expression of a foreign protein by influenza a this report we describe the rescue of a transfectant influenza a virus which stably expresses a heterologous protein, bacterial chloramphenicol acetyltransferase (cat). the foreign sequences encoding cat are expressed as part of an essential influenza virus segment, that coding for the neuraminidase (na) protein. the novel way by which this was achieved involved inserting in frame the 16-amino-acid self-cleaving 2a protease of foot-and-mouth disease virus between the cat and the na coding seq ...19948207822
use of combined shewhart-cusum control charts in internal quality control of enzyme-linked immunosorbent assays for the typing of foot and mouth disease virus enzyme-linked immunosorbent assay (elisa) for the typing of foot and mouth disease virus (fmdv) antigen was employed for the routine laboratory diagnosis of fmd at a regional veterinary laboratory in northern thailand. an objective procedure was developed to monitor the test performance of the elisa, using absolute test control limits in a shewhart-cusum (cumulative sum) control chart method. the procedure detected significant data trends and 'beyond control limit' situations for each antigen ...19947949345
establishment of a typing enzyme-linked immunosorbent assay for foot and mouth disease antigen, using reagents against viruses endemic in thailand.antisera were produced at a central laboratory in thailand against the endemic serotypes (o, a and asia 1) of foot and mouth disease (fmd) virus. at a regional veterinary laboratory, these antisera were used in an indirect sandwich enzyme-linked immunosorbent assay (elisa) for the detection and serotyping of fmd virus (fmdv) antigen. elisa readings of < 0.10 optical density (od) units were considered negative. this was verified using fifty tissue samples which were known to be negative for fmdv. ...19947949346
t cell-stimulatory fragments of foot-and-mouth disease virus released by mild treatment with cathepsin d.cathepsin d and cathepsin b are endosomal/lysosomal proteases that are thought to play a role during in vivo antigen processing, releasing fragments for binding to major histocompatibility complex class ii products and subsequent presentation to t cells. here we treated purified foot-and-mouth disease virus (fmdv) strain a10holland with both enzymes. cathepsin d, but not cathepsin b, was shown to release fragments from reduced or non-reduced fmdv under mild conditions in vitro. twenty-eight pred ...19947964603
haptoglobin response of cattle infected with foot-and-mouth disease virus.haptoglobin, a major bovine acute phase protein, was evaluated as a marker of the primary replication of foot-and-mouth disease virus in 12 naturally infected cattle from which blood was collected daily. an acute phase response, as measured by an increase in serum haptoglobin concentration and the presence of fever, was not detected during the previraemic stage of disease, but there was a significant increase in serum haptoglobin after the onset of viraemia. it occurred on the same day as the fi ...19947973086
need for cellular and humoral immune responses in bovines to ensure protection from foot-and-mouth disease virus (fmdv)--a point of view.the published studies on immunization of experimental animals, cattle, and sheep with synthetic peptides containing the antigenic domains in fmdv structural protein vp1 were analyzed. the results obtained with various fmdv synthetic peptides designed to stimulate the humoral immune response in bovines were compared to the current knowledge on mhc class i and class ii, and the properties of the peptide binding grooves in each of them. x-ray crystallography of mhc class i proteins provided the thr ...19947975267
nucleotide sequence of the p1 region of serotype asia1 foot-and-mouth disease virus.differences in the amino acid sequence of foot-and-mouth disease virus (fmdv) virion proteins (vp) among the various fmdv serotypes, particularly in the vp1 polypeptide, are the basis for antigenic diversity of this virus group. this phenomenon provides the basis for type diagnosis of fmdv by the polymerase chain reaction (pcr). in order to specifically identify the asia1 fmdv serotype by pcr, the nucleotide sequence of its p1-coding region was determined. the sequence exhibited over 70% homolog ...19947975273
effect of adjuvant formulations on the induction of virus-neutralizing and virus-binding antibodies by chemosynthetic peptides of vp1 of foot-and-mouth-disease virus.synthetic peptides corresponding to the 141-160 amino acid sequence of the protein vp1 of virus type o1 kaufbeuren (o1k) and a5 riems (a5r) were conjugated to thyroglobulin and mixed with complete freund's adjuvant (cfa) or incomplete freund's adjuvant (ifa) together with quil a. although the peptide of a5r, together with ifa and quil a, or with cfa, elicited a high antibody response to the virus in the elisa, formula containing both ifa and quil a induced only high titres of virus-neutralizing ...19947985430
insertion of a 27 amino acid viral peptide in different zones of escherichia coli beta-galactosidase: effects on the enzyme internal, putatively exposed regions of escherichia coli beta-galactosidase have been explored regarding their tolerance to insertions of large foreign peptides. small sequence modifications, including amino acid substitutions and small deletions, were introduced into the lacz gene to generate unique bamhi restriction sites. by using these mutant genes, a 27 amino acid stretch reproducing the hypervariable loop of foot-and-mouth disease virus vp1 protein (site a) was further inserted in pr ...19947988875
immunogenicity of non-structural proteins of foot-and-mouth disease virus: differences between infected and vaccinated swine.non-structural as well as vp1 recombinant proteins of foot-and-mouth disease virus (fmdv) produced in e. coli, have been used to study the specific antibody response of infected or vaccinated swine. an analysis of sera from infected pigs, using a direct elisa, showed that polypeptide 3abc (spanning non-structural proteins 3a, 3b and 3c) was the most antigenic among the recombinant proteins studied and allowed specific detection of fmdv infected swine from the second week after the infection. the ...19948002780
[synthesis of new fragments of vp1 protein fragments from foot and mouth disease virus type a22. synthesis of fragments 134-139, 134-145, 140-145, 150-155, and 150-159].fragments 134-145 and 150-159 of the antigenic-region of the vp1 protein of the a22 foot-and-mouth disease virus were synthesized by classic methods of peptide chemistry with isobutyl chloroformate as a coupling reagent. after purification by hplg and amino acid analysis, the free peptides h-gly-lys-tyr-ser-ala-gly-gly-leu-gly-arg-arg-gly-oh and h-leu-ala-ala-arg-val-ala-lys-gln-leu-pro-oh were conjugated with bsa by means of n,n-dicyclohexylcarbodiimide. the conjugates were used, with complete ...19948003043
efficient use of lactose for the lac promoter-controlled overexpression of the main antigenic protein of the foot and mouth disease virus in escherichia coli under fed-batch fermentation conditions.derivatives of the lac promoter (tac, pac, rac) belong to the strongest bacterial promoters which are frequently used for the induced overexpression of foreign genes in escherichia coli. however, their use in fermentation processes is strongly restricted because of the high cost of the inducer iso-propyl-beta-d-thiogalactopyranoside (iptg). the aim of this work was to investigate the possibility of using lac-derived promoters in high cell density processes resulting in a high yield of the induce ...19948011364
development of cowpea mosaic virus as a high-yielding system for the presentation of foreign has recently been shown that cowpea plants can be infected with a cowpea mosaic virus (cpmv) chimera containing an antigenic site from foot-and-mouth disease virus (usha et al., virology 197, 366-374, 1993). analysis of progeny rna produced during such an infection has revealed that the inserted sequence is rapidly lost during serial passaging, probably by a process of homologous recombination. using the information gained from this analysis, we have redesigned the chimeras in such a way that ...19948030255
analysis of sites of foot and mouth disease virus persistence in carrier cattle via the polymerase chain reaction.this study was undertaken in order to explore possible sites of foot-and-mouth disease virus (fmdv) persistence during the carrier state. tissue samples taken from experimentally infected animals at different times post-infection (p.i.) were examined by conventional viral isolation and the polymerase chain reaction (pcr) technique. the analysis of samples from several organs taken from 17 bovines between 3 and 270 days p.i. allowed the following conclusions: 1) virus present in oesophageal-phary ...19948031235
the structure of an immunodominant loop on foot and mouth disease virus, serotype o1, determined under reducing conditions.residues 136-159 of vpi of foot and mouth disease virus (fmdv) comprise the g-h loop of the protein and form a prominent feature on the surface of virus particles. this sequence contains an immunodominant neutralizing epitope, which can be mimicked with synthetic peptides, and includes an arg, gly, asp motif which has been implicated in the binding of the virus to cellular receptors. crystallographic analysis of native virus particles failed to resolve the structure of this region due to its dis ...19948032279
comparison of liquid-phase and mab-blocking elisa for assessment of the reactivity of monoclonal antibodies to foot-and-mouth disease virus. 19948034975
animal-derived antigenic variants of foot-and-mouth disease virus type a12 have low affinity for cells in culture.we recently have shown that binding of foot-and-mouth disease virus (fmdv) to cells in culture requires an arginine-glycine-aspartic acid (rgd) sequence in the g-h loop of the capsid protein vp1 (p. w. mason, e. rieder, and b. baxt, proc. natl. acad. sci. usa 91:1932-1936, 1994). in this report, we show that fmdv type a12 viruses found in infected bovine tongue tissue (btt) differ from their tissue culture-grown derivatives at amino acid residues near the rgd. viruses genetically engineered to c ...19948035529
ompa-fmdv vp1 fusion proteins: production, cell surface exposure and immune responses to the major antigenic domain of foot-and-mouth disease virus.exposure at the bacterial outer surface of the major antigenic epitope of the foot-and-mouth disease (fmdv) viral protein vp1 was studied using protein fusion with outer membrane protein a (ompa) of shigella dysenteriae for production and transport of the foreign polypeptide to the outer membrane of escherichia coli. fusion constructs with vp1 peptide insertions of up to 56 amino acids in the third outer domain of ompa could be demonstrated on the bacterial surface by indirect immunofluorescence ...19948036821
modelling the spread of foot-and-mouth disease virus.foot-and-mouth disease is an economically important viral disease in animals. it is shown that airborne diffusion is one of the main sources of contamination between animals and between herds. epidemiological data linked to viral particle excretion can thus be used in a predictive model, added to meteorological data related to the few days before the slaughter of animals. the model computes, on a 10 km radius around the outbreak and in every space direction, the quantity of viral particles that ...19948038801
a comparative study of serological and biochemical methods for strain differentiation of foot-and-mouth disease type a viruses.three serological and three biochemical methods were used to compare five field isolates of foot-and-mouth disease virus (fmdv) from western india with nine reference vaccine strains and five field isolates from other countries. the serological tests (liquid-phase elisa and virus neutralization) were able to distinguish between the three reference vaccine strains examined, but the five indian field isolates reacted poorly with antisera produced against these vaccine strains. analysis of monoclon ...19948042276
induction of effective cross-reactive immunity by fmdv peptides is critically dependent upon specific mhc-peptide-t cell interactions.bocd4+ t-cell clones specific for a peptide derived from foot-and-mouth disease virus envelope protein, vp1 (fmdv15) were generated from two responder cattle. one animal was a high and the other was an intermediate responder in terms of both t-cell and antibody responses. however both animals had identical major histocompatibility complex (mhc) class ii dr-like types (drbf3,6) according to a one-dimensional isoelectric focusing method which distinguishes dr-like alleles. in contrast, mixed lymph ...19948045586
foot-and-mouth disease virus leader proteinase: purification of the lb form and determination of its cleavage site on eif-4 gamma.many picornaviruses cause a dramatic decrease in the translation of cellular mrnas in the infected cell, without affecting the translation of their own rna. specific proteolysis of protein synthesis initiation factor eif-4 gamma occurs during infection with rhinoviruses, enteroviruses, and aphthoviruses, apparently leading to an inability of the ribosomes to bind capped mrnas. cleavage of eif-4 gamma in human rhinoviruses and enteroviruses is carried out by the viral 2a proteinase; in aphthoviru ...19948057448
dituftsin and polytuftsin induce an anti-peptide igg response to non-immunogenic peptides in mice.the effect of covalently attaching multiple forms of the immunomodulating tetrapeptide tuftsin to normally non-immunogenic peptides was studied in balb/c and c57bl/6 mice. the peptides: (nanp)3 from the plasmodium falciparum circumsporozoite protein and peptides 136-152 and 205-213 derived from the capsid protein of foot-and-mouth disease virus were coupled to polytuftsin or dituftsin. anti-peptide igg titers were determined after two immunizations. all of these three non-immunogenic peptides co ...19948070848
direct pcr detection of foot-and-mouth disease virus.a pcr assay for the detection and characterization of foot-and-mouth disease virus was developed. the procedure allows rt-pcr amplification following direct adsorption of viral suspensions to microtiter plates, avoiding previous steps of phenol-extraction or heating. using this procedure, fmdv-specific (based on 3d gene sequences), as well as serotype-specific (based on vp1 gene sequences) amplification were achieved for viral samples of serotypes a, o and c, either from cell culture supernatant ...19948071421
sequence of the s fragment of foot-and-mouth disease virus type a12.the foot-and-mouth disease virus (fmdv) genome contains a 5' untranslated region (s fragment) capable of forming a stem-loop structure of over 350 bases, which is separated from the remainder of the genome by a homopolymeric cytidylic acid tract (poly(c)) of variable length. the sequence of the s fragment of serotype a12 appears more similar to those of type o1 or type c3 than to subtype a10. the relatively large difference between the s fragment sequences of two type a viruses suggests that the ...19948073639
circular dichroism, molecular modeling, and serology indicate that the structural basis of antigenic variation in foot-and-mouth disease virus is alpha-helix antigenic variants obtained from a single field isolate of foot-and-mouth disease virus, serotype a12, differ only at residues 148 and 153 in the immunodominant loop of viral protein vp1. synthetic peptides corresponding to the region 141-160 are highly immunogenic. uv circular dichroism shows that (i) in aqueous solution the peptides are nearly identical, but in 100% trifluoroethanol they display helix-forming properties which correlate well with their serological crossreactivities for an ...19948078900
genetic variation of foot-and-mouth disease virus from field outbreaks to laboratory isolation.foot-and-mouth disease virus (fmdv), by nature of its rna genome, possesses a high rate of mutation during replication. this results in extensive genetic polymorphism of virus populations in nature. the emergence of fmdv variants during replication has been reported. genetic changes in the viral capsid protein (vp1) gene can result in amino acid changes affecting the immunodominant epitopes of fmdv. the genetic heterogeneity of fmdv in the field and the antigenic variants observed after cell cul ...19948079512
the structure and antigenicity of a type c foot-and-mouth disease virus.picornaviruses are responsible for a wide range of mammalian diseases and, in common with other rna viruses, show considerable antigenic variation. foot-and-mouth disease viruses (fmdvs) constitute one genus of the picornavirus family and are classified into seven serotypes, each of which shows considerable intratypic variation. this antigenic variation leads to continuing difficulties in controlling the disease. to date the structure of only one serotype, o, has been reported.19948081743
application of monoclonal antibodies to quality control of foot-and-mouth disease vaccines.panels of monoclonal antibodies (mabs) produced against foot-and-mouth disease (fmd) virus types o, a and c were selected for cell culture neutralization titre (nt), mouse protection index (mpi), trypsin sensitivity (ts) and avidity to different epitopes. the selected sets were used to assay the antigen concentration and the fit between fmdv vaccine and challenge strains. it was observed that fmd vaccines protect more than 75% of vaccinated cattle when manufactured with antigens characterized by ...19948091844
foot-and-mouth disease in ethiopia from 1988 to 1991.during the period 1988 to 1991 samples from 16 foot-and-mouth disease outbreaks in ethiopia were examined at the national veterinary institute, ethiopia, and at the fao world reference laboratory for foot-and-mouth disease, uk. typing of the virus responsible was possible in 13 of these outbreaks representing 10 separate disease events; 8 of these were caused by serotype o and 2 by serotype sat2. this is the first record of the presence of serotype sat2 foot-and-mouth disease virus in ethiopia. ...19947809989
demonstration of antibodies against foot and mouth disease virus (fmdv) type o and asia-1 in non-descriptive crossbred calves.sera from non-descriptive crossbred calves were screened for the presence of neutralizing antibodies against fmdv type o and asia-1 for a period up to 215 days. the antibody titer of 16 remained constant up to 215 days against type o and up to 190 days against type asia-1 virus in some animals. in majority of the animals the antibody titers remained constant up to three months. the possible reason for a frequent breakdown of immunity in the vaccinated animals even 3-4 months after vaccination co ...19947817899
genetic variation of foot-and-mouth disease virus during persistent infection in cattle.genetic variation of foot-and-mouth disease virus o1 campos has been analyzed in consecutive isolates recovered over a one- or two-year period from four cattle with experimental persistent infection. comparisons of rnase t1 two-dimensional maps and nucleotide sequences of the vp1-coding region revealed a continual, although irregular, increase in the fixation of mutations as the infection progressed. most changes were not conserved in consecutive isolates. these results, together with the substa ...19947831963
a modified liquid phase (lp) blocking elisa used to assess type o foot-and-mouth disease virus antigenic variation in thailand.a selection of type o foot-and-mouth disease (fmd) viruses isolated in thailand between 1986 and 1989 were compared to the reference viruses o1 thailand 1960 (o bkk/60) and o nakorn pathom 1965 (o npt/65) using a liquid-phase blocking elisa (lp elisa) to derive serum titres and associated r values. interpolation techniques were used to increase the precision for estimation of r values through a more accurate estimation of serum titres at predicted equivalent levels of antigen input. mean r value ...19947839587
validation of an inhibition elisa using a monoclonal antibody for foot-and-mouth disease (fmd) primary inhibition elisa (ih-elisa) test for foot-and-mouth disease virus (fmdv) was validated using 106 epithelial samples from suspected cases of fmd in argentina submitted to the argentine national diagnostics laboratory (gelab) over a period of 12 months and examined in parallel with the complement fixation test (cft). ih-elisa was found to be more sensitive, detecting 25% (26 samples) more fmdv positives than the cft in original suspensions of field samples. the effect of storage conditions on 1 ...19947839753
rapid coagglutination test for the detection and typing of foot and mouth disease virus.protein a containing staphylococcus aureus was used to develop a coagglutination (coa) test for the detection and typing of foot and mouth disease virus (fmdv) o, a and c serotypes in infected cells and tissues. different batches and amounts of guinea pig anti-fmdv sera were assessed to optimize the preparation of coa conjugates. the sensitivity and specificity of the coa test for the detection of fmdv o, a and c serotypes and heterologous viruses was also characterized. comparison between the c ...19947714052
immunogenicity of foot-and-mouth disease virus grown in bhk-21 suspension cells. correlation with cell ploidy alterations and abnormal expression of the alpha 5 beta 1 integrin.bhk-21 suspension cells were characterized with regard to genetic and phenotypic features which might adversely affect the immunogenic properties of foot-and-mouth disease virus (fmdv) grown therein. a positive correlation was found between number of passages in suspension culture and both prevalence of polyploid cells and reduced cell growth on surfaces. suspension cells also revealed differences in the expression of rgd-specific integrins and, in particular, of alpha 5 beta 1, which was shown ...19947511862
unprocessed foot-and-mouth disease virus capsid precursor displays discontinuous epitopes involved in viral neutralization.a foot-and-mouth disease virus (fmdv) cdna cassette containing sequences encoding the capsid precursor p1, peptide 2a and a truncated 2b (abbreviated p1-2a) of type c fmdv, has been modified to generate the authentic amino terminus and the myristoylation signal. this construct has been used to produce a recombinant baculovirus (acmm53) which, upon infection of spodoptera frugiperda insect cells, expressed a recombinant p1-2a precursor with a high yield. this polyprotein reacted with neutralizing ...19947515974
vaccines prepared from chimeras of foot-and-mouth disease virus (fmdv) induce neutralizing antibodies and protective immunity to multiple serotypes of fmdv.the g-h loop of vp1 (residues 132 to 159) of foot-and-mouth disease virus (fmdv) is a prominent feature on the virion surface and has an important role in vaccine efficacy, generation of antigenic variants, and cell binding. using an infectious cdna of fmdv, we have constructed serotype a viruses in which the g-h loop has been substituted with the homologous sequences from serotype o or c. these chimeric viruses replicated to high titer and displayed plaque morphologies similar to those of wild- ...19947523697
antigenic specificity of porcine t cell response against foot-and-mouth disease virus structural proteins: identification of t helper epitopes in vp1.the contribution of each of the viral capsid proteins of foot-and-mouth disease virus (fmdv) in the t cell response of vaccinated pigs has been studied. viral polypeptides, vp1 to vp4, were expressed as fusion proteins in escherichia coli, and were used to stimulate peripheral blood mononuclear cells of vaccinated animals. significant, dose-dependent responses to whole virion were detected in the seven animals analyzed and, in five of them, responses to recombinant polypeptides vp1, vp2, and vp3 ...19947526534
antibodies to the vitronectin receptor (integrin alpha v beta 3) inhibit binding and infection of foot-and-mouth disease virus to cultured cells.the amino acid sequence arg-gly-asp (rgd) is highly conserved on the vp1 proteins of different serotypes and subtypes of foot-and-mouth disease virus (fmdv) and is essential for cell attachment. this sequence is also found in certain extracellular matrix proteins that bind to a family of cell surface receptors called integrins. within the picornaviridae family, enterovirus coxsackievirus a9 also has an rgd motif on its vp1 capsid protein and has recently been shown to utilize the vitronectin rec ...19957533862
the influence of mhc polymorphism on the selection of t-cell determinants of fmdv in cattle.there is a quest for the development of a new generation of vaccines consisting of well-defined subunit antigens. for a number of practical reasons it is attractive to develop vaccines on the basis of synthetic peptides. however, their efficacy may be limited by genetic restrictions imposed on t-cell recognition via major histocompatibility complex (mhc) polymorphism, as shown by many studies using inbred animal species. to study the effect of mhc polymorphism in an outbred species, we selected ...19957534267
structure of the major antigenic loop of foot-and-mouth disease virus complexed with a neutralizing antibody: direct involvement of the arg-gly-asp motif in the interaction.the crystal structure of a synthetic peptide representing the major antigenic loop of foot-and-mouth disease virus (fmdv), complexed with the fab fragment of a neutralizing monoclonal antibody raised against the virus, has been determined at 2.8 a resolution. the peptide shows a high degree of internal structure with a nearly cyclic conformation. the conserved arg-gly-asp motif, involved in the viral attachment of aphtoviruses to cells, participates directly in the interaction with several compl ...19957537661
response of foot-and-mouth disease virus c3 resende to immunological pressure exerted in vitro by antiviral polyclonal sera.the foot-and-mouth disease virus (fmdv) shows a remarkable antigenic variability. like other rna viruses, fmdv has a high mutation rate and it has been proposed that selection exerted by antibodies of the host could play a major role in its evolution. in this work, antiserum-resistant variants of fmdv (nr variants) were selected upon 25 serial passages of a cloned c3 resende strain on secondary monolayers of fetal bovine kidney (fbk-2) cells in the presence of subneutralizing levels of antiviral ...19957542827
antigenic analysis of sat 2 serotype foot-and-mouth disease virus isolates from zimbabwe using monoclonal antibodies.this paper compares strains of foot-and-mouth disease (fmd) serotype sat (south african territories) 2 viruses isolated from zimbabwe and other african countries using monoclonal antibodies (mab). a sandwich-elisa was used to examine the relative binding of anti-sat 2 mab to the various viruses. the mab-binding profiles of viruses isolated from field samples were compared using hierarchical cluster analysis. viruses were obtained from game animals, mainly african buffalo (syncerus caffer) which ...19957543860
[susceptibility of picornaviruses++ to an antiviral of plant origin (meliacin)].meliacine, a peptide associated with antiviral activity isolated from the high plant melia azedarach l (ma) inhibits the replication of different strains of foot and mouth disease virus (fmdv) and poliovirus in bhk-21 or vero cells, respectively, infected at a multiplicity of infection (m.o.i.) of 1. a leaf extract of ma, containing meliacine was added to the culture medium after virus adsorption and maintained up to virus harvest (18 hs). fmdv o1 campos and o69 strains showed 60% and 52% inhibi ...19957568867
a 10-amino-acid linear sequence of vp1 of foot and mouth disease virus containing b- and t-cell epitopes induces protection in mice.the area of foot and mouth disease virus (fmdv) comprising residues 140 and 160 of capsid protein vp1 has been used extensively as an immunogen in natural and experimental hosts. a detailed epitope mapping of this region, however, has not been reported. for this purpose a synthetic peptide containing the residues 135 to 160 (p135-160) of vp1 of fmdv o1 campos was analyzed for its t- and b-cell epitopes. the p135-160 is highly immunogenic, either by itself or coupled to a carrier protein (bsa), e ...19957571431
inactivation of viruses in liquid manure.the stability of some viruses and methods of virus inactivation in liquid manure are reviewed. the authors discuss experimental data on the stability of foot and mouth disease virus, classical swine fever virus, aujeszky's disease virus, african swine fever virus, swine influenza virus, porcine paramyxovirus, bovine virus diarrhoea virus and transmissible gastroenteritis of pigs virus. recommendations and practical advice are given for the choice and application of chemical disinfectants for slu ...19957579641
use of disinfectants in zoos and game parks.disinfection is used in the animal quarters of zoos and game parks as an adjunct to physical cleaning and the removal of potentially contaminated materials. disinfection is particularly useful in reducing infection risks in young animal nursery facilities, and in routine cleaning operations of animal quarters and feeding utensils. specific disinfectants may be selected for certain known microbial contaminants following an infectious disease outbreak. for example, premises contaminated by foot an ...19957579642
m7gpppg cap dependence for efficient translation of drosophila 70-kda heat-shock-protein (hsp70) investigate whether preferential translation of the heat-shock mrnas occurs via cap-independent translation, the requirement for the m7gpppg cap structure for efficient translation of 70-kda heat-shock-protein (hsp70) mrna was quantified by in vitro translation and by in vivo translation following electroporation. hsp70 mrna was transcribed in vitro with and without a cap structure. translation in the rabbit reticulocyte or wheat germ lysate was reduced about 70% when the cap was absent. for ...19957588716
a recombinant foot-and-mouth disease virus antigen inhibits dna replication and triggers the sos response in escherichia coli.the 3d gene of foot-and-mouth disease virus encodes the viral rna dependent rna polymerase, also called virus infection associated (via) antigen, which is the most important serological marker of virus infection. this 3d gene from a serotype c1 virus has been cloned and overexpressed in escherichia coli under the control of the strong lambda lytic promoters. the resulting 51 kda recombinant protein has been shown to be immunoreactive with sera from infected animals. after induction of gene expre ...19957607396
identification of the active-site residues of the l proteinase of foot-and-mouth disease virus.the foot-and-mouth disease virus (fmdv) leader (l) protein is involved in autocatalytic cleavage at the l/p1 junction and in the cleavage of translation initiation factor p220, a subunit of the cap-binding protein complex. it has been suggested that this proteinase has homology to the papain-like family of cysteine proteinases, and from this information, we have investigated the active-site residues by introducing specific mutations into the l gene. mutations of cys-23 to ala or his-120 to leu r ...19957609064
[the use of a carboxymethylcellulose coating for titrating the foot-and-mouth disease virus by the plate-culture method]. 19957620781
bovine t cells preferentially recognize non-viral spacer epitopes in a putative fmdv vaccinal a group of immunized cattle with a variety of mhc class ii types, t-cell responses were detected to a synthetic peptide (fmdv15) proposed as a basis for a vaccine against foot-and-mouth disease. this peptide combines the loop region of vp1 with the c-terminal sequence connected by a spacer (pps). two major immunodominant regions of fmdv15 for bovine t cells were detected, one within the loop region and the other around the spacer. a substantial proportion of the t-cell response to fmdv15 was ...19957625121
the foot-and-mouth disease virus leader proteinase gene is not required for viral replication.the foot-and-mouth disease virus (fmdv) leader (l) proteinase has only two known functions: (i) autocatalytic removal from the n terminus of the viral polyprotein and (ii) cleavage of the p220 subunit of the eukaryotic initiation factor 4f complex, which helps to shut off host protein synthesis. cleavage of p220 appears to be important for picornavirus replication, since rhinoviruses and enteroviruses utilize a different proteinase (2a) to cleave p220. to explore the role of l in fmdv replicatio ...19957636982
receptor binding site-deleted foot-and-mouth disease (fmd) virus protects cattle from fmd.binding of foot-and-mouth disease virus (fmdv) to cells requires an arginine-glycine-aspartic acid (rgd) sequence in the capsid protein vp1. we have genetically engineered an fmdv in which these three amino acids have been deleted, producing a virus particle which is unable to bind to cells. cattle vaccinated with these receptor binding site-deleted virions were protected from disease when challenged with a virulent virus, demonstrating that these rgd-deleted viruses could serve as the basis for ...19957637023
ultrastructural and replicative features of foot-and-mouth disease virus in persistently infected bhk-21 cells.persistent foot-and-mouth disease (fmd) virus infection in vitro has been studied in a chronically infected cloned bhk-21 cell line. virus growth during serial cell passages was followed by infectivity assay and immunocytochemical staining. only a small percentage of cells (0.006-6%) was found to harbour virus during persistence. light and electron microscopy showed the presence of cytoplasmic protuberances ("blebs") at the surface of persistently infected cells. the curing of cell cultures was ...19957646338
mapping of functional domains in eukaryotic protein synthesis initiation factor 4g (eif4g) with picornaviral proteases. implications for cap-dependent and cap-independent translational initiation.cap-dependent binding of mrna to the 40 s ribosomal subunit during translational initiation requires the association of eukaryotic initiation factor 4g (eif4g; formerly eif-4 gamma and p220) with other initiation factors, notably eif4e, eif4a, and eif3. infection of cells by picornaviruses results in proteolytic cleavage of eif4g and generation of a cap-independent translational state. rhinovirus 2a protease and foot-and-mouth-disease virus l protease were used to analyze the association of eif4 ...19957665619
enhanced immunogenicity and cross-reactivity of retro-inverso peptidomimetics of the major antigenic site of foot-and-mouth disease virus.retro-inverso analogues of peptides corresponding to the major antigenic site 141-159 of vp1 from two foot-and-mouth disease virus variants have been synthesized and tested for their antigenic and immunogenic properties. antibodies to the l- and retro-inverso peptides were produced by injecting rabbits with peptides covalently coupled to small unilamellar liposomes containing monophosphoryl lipid a as adjuvant. when compared to the antibody response raised against the l-peptides, the duration of ...19957670228
effect of cleavage of the p220 subunit of eukaryotic translation initiation factor eif-4f on protein synthesis in vitro. 19957672346
detection of foot-and-mouth disease virus in nasal swabs of asymptomatic cattle by rt-pcr within 24 hours.a method for extracting rna from animal-derived materials that provides foot-and-mouth disease viral template suitable for tth polymerase-dependent synthesis of cdna and subsequent pcr is described. viral genomes were detected in less than 24 h. nasal swabs that can be easily and repeatedly collected, proved suitable for virus detection by pcr, even during the asymptomatic stages of infection.19957673392
effect of expression of the aphthovirus protease 3c on viral infection and gene expression.cells transformed with specific regions of the foot-and-mouth disease virus (fmdv) genome have been constructed and analyzed with respect to viability and susceptibility to fmdv infection. constitutive expression of an active protease 3c under the control of the tk promoter has been documented by the ability of transformed cells to catalyze the processing of a p1 capsid precursor. high-level, transient expression but not low-level, constitutive expression, of 3c caused a 10-fold reduction in the ...19957676620
[cloning fragments of the rna polymerase gene of an attenuated variant of the foot-and-mouth disease virus a22].the cdna fragments complementary to rna-polymerase gene and 3'-untranslated genome region of attenuated foot-and-mouth disease virus strain a(22)645 have been synthesized and cloned into a plasmid vector puc19 in e. coli jm109. the cloned cdna fragments were characterized as to their size, orientation towards the plasmid, and localization in the virus genome. restriction maps for complete gene and two cdna clones were constructed.19957477032
picornavirus internal ribosome entry segments: comparison of translation efficiency and the requirements for optimal internal initiation of translation in vitro.on the basis of primary sequence comparisons and secondary structure predictions, picornavirus internal ribosome entry segments (ireses) have been divided into three groups (entero- and rhinoviruses; cardio- and and aphthoviruses; and hepatitis a virus). here, we describe a detailed comparison of the ability of ireses from each group to direct internal initiation of translation in vitro using a single dicistronic mrna (the only variable being the ires inserted into the dicistronic region). we st ...19957478993
identification of critical amino acids within the foot-and-mouth disease virus leader protein, a cysteine protease.the leader protein of foot-and-mouth disease virus (fmdv) is the first component of the virus polyprotein. it is synthesized in two forms, lab and lb, both of which display the ability to cleave the l/p1 junction in trans and to induce the cleavage of the cap-binding complex component eif-4g (p220). the l protease has weak homology to the family of cysteine proteases, which have a catalytic dyad composed of a cysteine and a histidine. mutations have been introduced into fmdv cdna to modify each ...19957483257
foot and mouth disease virus replication in bovine skin langerhans cells under in vitro conditions detected by rt-pcr.the replication of foot and mouth disease virus (fmdv) was studied in isolated bovine skin langerhans cells (lc), in keratinocytes from epidermal cell suspension, and in migrating lc obtained from cultured bovine epidermal sheets in vitro. viral rna replication in infected cells was determined by the reverse transcriptase-polymerase chain reaction (rt-pcr) of the negative fmdv rna strand and by the plaque forming assay of fmdv. it was established that bovine skin lc, keratinocytes, and migratory ...19957483289
immune response of calves to foot-and-mouth disease virus vaccine emulsified with oil adjuvant. strategies of vaccination.calves born to vaccinated cows under the regular annual vaccination programme were vaccinated at different ages using commercial quadrivalent (01, a79, a87 and c85 fmdv strains) vaccine emulsified in oil adjuvant. the antibody responses of vaccinated calves were evaluated using liquid-phase blocking sandwich elisa. all calves 20, 30 and 40 days old having high maternal antibody titres responded well to vaccination. moreover, 25-57% of vaccinated calves showed protective antibody titres both at 9 ...19957483763
isotype profiles induced in balb/c mice during foot and mouth disease (fmd) virus infection or immunization with different fmd vaccine formulations.the igg isotype response in balb/c mice infected with fmdv or immunized with different vaccine formulations using inactivated virus particles as antigen was analyzed at various times post-inoculation. for this purpose an elisa based on polyclonal antibodies for detection and quantification of mouse igg isotypes with fmd virus (fmdv) specificity was developed. three immunomodulators, which have been shown to be very effective in inducing strong and long-lasting antibody responses (bahnemann, arch ...19957483770
antigenic variants in a plaque-isolate of foot-and-mouth disease virus: implications for vaccine production.the occurrence of many subtypes within a serotype of foot-and-mouth disease virus (fmdv) makes it difficult to control the disease by vaccination. although inactivated vaccines are used successfully in many countries, the appearance in the field of antigenic variants against which the vaccines do not confer protection is a constant problem in vaccine manufacture. we had found previously a mixture of antigenic variants in a field isolate of serotype a12. in this report we demonstrate the presence ...19957483796
in vitro synthesis of foot-and-mouth disease virus specific antibodies by porcine leukocytes.we have characterized the in vitro secondary antibody response to fmdv of peripheral blood mononuclear cells (pbmc) from immunized pigs. the results obtained indicated that primed swine leukocytes can support an in vitro t-b cell cooperation which is functional and leads to the production of viral specific antibodies. the response was shown to be independent of viral replication, being induced by both infective and inactivated virus as well as by recombinant polypeptides vp1 and vp3. in all case ...19957487496
pathogenesis of foot-and-mouth disease in swine, studied by in-situ hybridization.eight 7-month-old pigs were inoculated intradermally with 10(3) plaque-forming units of foot-and-mouth disease virus, type o, and killed 24, 48, 72, or 96 h later. numerous tissues from each animal were collected and examined histopathologically and by in-situ hybridization to determine the presence of virus and its correlation with lesion development. the probe for in-situ hybridization was a biotinylated 500-base negative-sense transcription product corresponding to a portion of the gene encod ...19957490337
identification of the active-site residues of the 3c proteinase of foot-and-mouth disease identify the active-site residues of the 3c proteinase of foot-and-mouth disease virus (fmdv), we introduced mutations into the 3c coding region and examined the activity of mutant enzymes on various substrates. based on alignment of fmdv 3c with other picornavirus 3c proteinases and with the trypsin family of serine proteinases, mutations were introduced at residues presumed to be part of the catalytic triad, involved in substrate binding, or present in nonconserved regions. wild-type and mu ...19957491782
quantification of whole virus particles (146s) of foot-and-mouth disease virus in the presence of virus subunits (12s), using monoclonal antibodies in a sandwich elisa.this paper describes a method for the specific quantification of whole virions of foot-and-mouth disease (146s) in the presence of virus subunits (12s). the method involves the use of virus neutralising monoclonal antibodies directed against a linear epitope of the vp1 loop region of a type o virus. the monoclonal antibodies were used as both capture and detecting reagents (labelled with horse radish peroxidase) in a sandwich elisa. such monoclonal antibodies also have the advantage that they do ...19957491813
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