PMID(sorted ascending)
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
[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
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
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
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
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
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
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
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
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
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
[a rapid solid-phase immunoenzyme method in the diagnosis of viral infections].an accelerated solid-phase enzyme-immunoassay has been developed which permits identification of antigens and antibodies to them within 30-40 min, even directly at the site of specimen collection. the method was tested on the models of foot-and-mouth disease virus, vesicular disease of swine, vesicular exanthema of swine, aujeszky's disease, leukemia, and coronavirus infection of cattle.19938303893
phenotypic and functional characterization of mouse attenuated and virulent variants of foot-and-mouth disease virus type o1 campos.a series of genetically related variants arising from a parental wild-type isolate of o1 campos and its tissue culture adapted variant were differentiated by various cell culture markers (temperature sensitivity, plaque size, viral yield) and lethality in mice. these isolates were additionally characterized functionally and biochemically by examining poly(c) length, rna synthesis, protein synthesis, and cell receptor binding. in primary bovine kidney cells, the virulent isolates had greater leve ...19938384748
detection of foot-and-mouth disease virus rna in clinical samples and cell culture isolates by amplification of the capsid coding region.foot-and-mouth disease is one of the most economically important virus diseases of livestock. two important requirements for the control of this disease are rapid laboratory diagnosis and epidemiological investigation. the use of the polymerase chain reaction method (pcr) to amplify specific nucleic acid regions offers the unique possibility of combining swift viral detection with the production of genetic material suitable for sequencing and other methods of molecular epidemiological analysis. ...19938391540
rhipicephalus zambeziensis unlikely to transmit foot-and-mouth disease virus.the potential of the ixodid tick, rhipicephalus zambeziensis, was investigated as a vector in the transstadial transmission of the foot-and-mouth disease virus by feeding nymphae on viraemic (log 1.0-4.0 tcid50/ml) cattle. suspensions were prepared, at various intervals after detachment, from pools of engorged nymphae--some of which were allowed to moult first. suspensions were inoculated into sucking mice, cell cultures and, in some cases, cattle to detect the fmd virus. newly moulted adult tic ...19938392681
the carrier state in foot and mouth disease--an immunological review.the carrier state in foot and mouth disease (fmd) is characterized by the asymptomatic low-level excretion of foot and mouth disease virus (fmdv) from the oropharynx of ruminants for periods that are species and virus strain-dependent. persistent infection with fmdv readily occurs following the failure of virus elimination at the acute stage of infection, a process thought to be mediated through the phagocytosis of antibody/virus immune complexes. recent evidence supports the view that carrier c ...19938392891
large-scale use of liquid-phase blocking sandwich elisa for the evaluation of protective immunity against aphthovirus in cattle vaccinated with oil-adjuvanted vaccines in argentina.specific serum activity levels against four reference strains of foot-and-mouth disease virus (fmdv) were evaluated from 1634 animals vaccinated with commercial quadrivalent oil vaccines and from 746 unvaccinated, naive animals, using the liquid-phase blocking sandwich elisa (lpelisa) test. cows from the fmdv-free area of argentina were tested for the absence of specific fmdv antibodies (sp fmdv abs) and those showing lpelisa titres < 1.0 were grouped in lots of 16 animals. they were vaccinated ...19938393607
identification of a fifth neutralizable site on type o foot-and-mouth disease virus following characterization of single and quintuple monoclonal antibody escape mutants.a monoclonal antibody (c3) produced against foot-and-mouth disease virus type o1caseros was found to neutralize quadrivalent monoclonal antibody escape mutant (g67) of foot-and-mouth disease virus type o1kaufbeuren. this mutant had been characterized at the sequence level as having distinct changes affecting four non-overlapping neutralizable sites. the c3 monoclonal antibody was used to prepare a quintuple escape mutant from the g67 and a single escape mutant from the parental o1kaufbeuren viru ...19938393912
the detection of foot-and-mouth disease virus in oesophageal-pharyngeal samples by a polymerase chain reaction technique.a polymerase chain reaction (pcr) technique was used to detect the presence of foot-and-mouth disease virus (fmdv) in oesophageal-pharyngeal(op) samples from experimentally infected steers. ten-fold dilutions of op samples were also diluted, inoculated onto lamb kidney cell cultures, and incubated overnight. the cultures that did not show overt cytopathogenic effects (cpe) of fmdv infection were frozen and thawed; both the fluid and the cell pellet were tested by the pcr technique. the pcr detec ...19938395537
cross-reactive idiotopes among anti-foot and mouth disease virus neutralizing antibodies.foot and mouth disease virus (fmdv) viral protein 1 is the only one of the four viral proteins (vp) that induces neutralizing antibodies as an isolated protein. a 32 amino acid (aa) residue (32dimer) of fmdv subtype a12 lp ab vp1 (aa 137-168) was immunogenic against the a12 subtype. three antibody populations each recognizing different epitopes on 32dimer were isolated by affinity chromatography (afc) from the serum of a steer which had been immunized with the 32dimer. the 32dimer contains an aa ...19938406565
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
identification of native foot-and-mouth disease virus non-structural protein 2c as a serological indicator to differentiate infected from vaccinated livestock.cattle and pigs which have been vaccinated against foot-and-mouth disease can be distinguished from convalescent animals by radio-immunoprecipitation and sodium dodecyl sulphate polyacrylamide gel electrophoresis of the virus-induced proteins reacting with the respective sera. baby hamster kidney cells infected with foot-and-mouth disease virus (fmdv) (serotype a24) were labelled with 35s-methionine and the virus-induced proteins were precipitated with sera from vaccinated and subsequently chall ...19958525090
the persistence of foot-and-mouth disease virus on wool.five suffolk sheep, held in a high-security isolation room, were exposed for 2 hours to the aerosol of 3 mature pigs that had been infected with foot-and-mouth disease virus (fmdv), strain o1-bfs. the fleeces of 3 of the sheep were contaminated with fmdv at 2 days post exposure (dpe), while at 5 dpe the fleeces of all 5 sheep were more extensively, and more heavily, contaminated. the persistence of fmdv on contaminated wool was examined in vitro using multiple 0.5 g samples of merino wool that w ...19958579558
assessment of foot and mouth disease vaccine potency by liquid-phase blocking elisa: a proposal for an alternative to the challenge procedure in argentina.the lowest expected protection (lep) at a 95% confidence of 245 foot and mouth disease (fmd) commercial vaccines was calculated from the titres of liquid-phase blocking sandwich elisa (lpelisa) of cattle sera obtained from 3920 animals at 60 days post-vaccination (d.p.v.) and challenged with live virus at 90 d.p.v. it was found that lep evaluation is highly specific (i.e. it is able to predict the failure in 100% of the cases) although its ability to predict the challenge (pg test) approval (i.e ...19958585292
serological comparison of type asia 1 foot and mouth disease virus isolates from thailand.antigenic variation of type asia 1 foot and mouth disease (fmd) virus in thailand was examined using a total of 50 field viruses isolated between 1986 and 1992. a two-dimensional serum neutralisation test was used to calculate r values for comparison of these isolates with a reference vaccine strain, asia 1 bangkok 1960 (bkk/60). viruses were also compared to two field isolates, asia 1 36-2/88 and asia 1 45/88, and some were compared to another vaccine strain, asia 1 nakhon pathom 1984 (npt/84). ...19958593388
serological comparison of type a foot and mouth disease virus isolates from thailand.antigenic variation of type a foot and mouth disease (fmd) virus in thailand was examined using a total of 82 field viruses isolated between 1986 and 1989. a two-dimensional serum microneutralisation test was used to compare these isolates to a reference strain, a15 bangkok 1960 (a bkk/60). viruses regarded as unrelated to a bkk/60 were compared to another reference strain, a22 nakhon pathom 1986 (a npt/86). this approach divided the viruses into two groups. most of the viruses shared a close an ...19958593389
susceptibility of llamas (lama glama) to infection with foot-and-mouth-disease experimental trial was conducted to evaluate the ability of foot-and-mouth-disease (fmd) virus (serotypes a79, c3, o1) to infect susceptible llamas exposed either directly to affected livestock, or indirectly to llamas that had been directly exposed to affected livestock. in addition, susceptible livestock species (cattle, pigs, goats, and sheep) were exposed to those llamas that had been both directly and indirectly exposed to the fmd virus to further look at potential transmission possibili ...19958594845
a protective anti-peptide antibody against the immunodominant site of the a24 cruzeiro strain of foot-and-mouth disease virus and its reactivity with other subtype viruses containing the same minimum binding sequence.a synthetic peptide vaccine of the general sequence cys-cys-(200-213)-pro-pro-ser-(l41-158)-pro-cys-gly(peptide a40), where the numbered residues refer to the vp1 sequence of foot-and-mouth disease virus (fmdv) strain a24 cruzeiro, has previously been shown to elicit neutralizing and protective antibodies in guinea-pigs and cattle. to examine this immunogenic tract in more detail monoclonal antibodies (mabs) were raised to this peptide. one such mab c1.1, which recognized the homologous peptide, ...19968609466
recognition of foot-and-mouth disease virus and its capsid protein vp1 by bovine peripheral t lymphocytes.the role of t cells in immunity to foot-and-mouth disease virus is still poorly defined compared to that of the humoral response. in this paper we describe a systematic, longitudinal study on the cellular recognition of fmdv and its subunit protein vp1 by bovine peripheral blood t lymphocytes. multiple vaccination with a single virus serotype induced a serotype cross-reactive proliferative t cell repertoire that varied in magnitude between individual animals and with the serotype of the vaccine ...19968627261
detection of foot-and-mouth disease viral sequences in various fluids and tissues during persistence of the virus in assess whether foot-and-mouth disease virus (fmdv)-specific sequences could be identified in tissues from persistently virus-infected animals.19968633795
rapid and sensitive polymerase chain reaction based detection and typing of foot-and-mouth disease virus in clinical samples and cell culture isolates, combined with a simultaneous differentiation with other genomically and/or symptomatically related viruses.reverse transcription followed by the polymerase chain reaction method (pcr) allowed the detection of foot-and-mouth disease virus (fmdv), regardless of the serotype. a primer set corresponding to highly conserved regions of the 2b sequence was selected. by combining in a single reaction tube specific primer pairs for fmdv, swine vesicular disease virus, (svdv), encephalomyocarditis virus (emcv) and bovine viral diarrhea virus (bvdv), all four viruses could be identified and differentiated in on ...19968634024
the use of cyclophosphamide as an enhancer of the vaccine against foot-and-mouth disease.the immunization of biungulate animals with killed foot-and-mouth disease virus (fmdv) requires periodic vaccinations due to a low vaccine immunogenicity. therefore, fmdv antigens need to be combined with adjuvants such as aluminium hydroxide, saponin or oil emulsions. animal handling for periodic inoculations, and the repeated doses of vaccines that have to be administered increase the commercialization costs. moreover, the use of adjuvants may induce adverse effects. in the present work we sho ...19968698098
strategy for producing new foot-and-mouth disease vaccines that display complex epitopes.widely used inactivated vaccines for foot-and-mouth disease (fmd) induce protective immunity, but vaccine production plants and residual virus in the vaccine itself have been implicated in disease outbreaks. the structure of the fmd virion has been determined, and although much of the surface of the viral particle is produced by complex folding of the three surface-exposed capsid proteins (vp1-3), some surface regions representing important linear epitopes can be mimicked by recombinant proteins ...19968717390
absence of protein 2c from clarified foot-and-mouth disease virus vaccines provides the basis for distinguishing convalescent from vaccinated animals.we have recently reported that cattle and pigs which have been vaccinated against foot-and-mouth disease can be distinguished from convalescent animals by the absence of antibodies to viral non-structural protein 2c (lubroth and brown, res. vet. sci., 1995, 59, 70-78(1)). in this study, we show that the absence of 2c antibodies from the sera of vaccinated animals can be explained by the association of this viral protein with cellular debris which is separated from the virus harvest prior to inac ...19968735554
detection of antibodies against foot-and-mouth disease virus using a liquid-phase blocking sandwich elisa (lpbe) with a bioengineered 3d protein.a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (elisa-3d) was developed to detect specific antibodies to the 3d protein in sera from foot-and-mouth disease (fmd) virus (fmdv)-infected animals. the assay uses a nonstructural 3d recombinant protein and two polyclonal antisera, one for capture (bovine) and the other for detector (guinea pig). the specificity of the assay was demonstrated by negative results with 101 sera of cattle from the fmd-free zone in argentina and with bov ...19968744733
persistent infection of african buffalo (syncerus caffer) with sat-type foot-and-mouth disease viruses: rate of fixation of mutations, antigenic change and interspecies transmission.transmission of a plaque-purified sat-2 foot-and-mouth disease virus (fmdv) occurred erratically from artificially infected african buffaloes in captivity to susceptible buffaloes and cattle in the same enclosure; in some instances transmission occurred only after contact between persistently infected carriers and susceptible animals lasting a number of months. because the rate at which fmdv mutations accumulated in persistently infected buffaloes was approximately linear (1.64 percent nucleotid ...19968757987
efficient infection of cells in culture by type o foot-and-mouth disease virus requires binding to cell surface heparan sulfate.foot-and-mouth disease virus (fmdv) enters cells by attaching to cellular receptor molecules of the integrin family, one of which has been identified as the rgd-binding integrin alpha(v)beta3. here we report that, in addition to an integrin binding site, type o strains of fmdv share with natural ligands of alpha(v)beta3 (i.e., vitronectin and fibronectin) a specific affinity for heparin and that binding to the cellular form of this sulfated glycan, heparan sulfate, is required for efficient infe ...19968764038
pathogenesis of wild-type and leaderless foot-and-mouth disease virus in cattle.four calves were experimentally infected via aerosol with foot-and-mouth disease virus. two were infected with a wild-type virus derived from a full-length infectious clone (a12-ic), and two were infected with a clone-derived virus lacking the leader gene (a12-llv2), with euthanasia and tissue collection at 24 and 72 h postexposure (hpe). clinical disease was apparent only in the animal given a12-ic and euthanized at 72 hpe. in situ hybridization revealed that the animal infected with a12-ic and ...19968764079
[nucleotide sequence of the rna polymerase gene attenuated by a variant of foot-and-mouth disease virus and its comparison with the virulence of related variants of subtype a22].the nucleotide sequence of rna-polymerase gene and 3'-terminal untranslated genome region of attenuated foot-and-mouth disease virus (fmdv) strain a(22)645 has been determined. rna-polymerase gene and predicted amino acid sequences of attenuated fmdv strain a(22)645 were compared with those of the original virulent fmdv strain a(22)550. the examined genome region of strain a(22)645 differed from that of strain a(22)550 by 22 nucleotides and 3 amino acids. three mutations occurred within nucleoti ...19968786750
identification of foot-and-mouth disease virus-free regions by use of a standardized enzyme-linked immunoelectrotransfer blot assess the potential of a highly sensitive enzyme-linked immunoelectrotransfer blot (eitb) assay to monitor persistent foot-and-mouth disease (fmd) viral activity in a livestock population.19968807005
preparation of virus-infection-associated (via) antigen of foot-and-mouth disease (fmd) virus from inactivated vaccine.virus-infection-associated (via) antigen of foot-and-mouth disease (fmd) virus was prepared from an inactivated fmd vaccine. the via antigen coupled with an adjuvant of aluminium hydroxide gel supplemented vaccine was efficiently eluted by suspending and stirring in high concentration of phosphate buffer solution (0.3m, ph 7.6). the final elute purified by deae-sephadex a50 from the vaccine was concentrated in 1/500-1/1,000 of the original volume. via antigens prepared from two kinds of vaccine ...19968811637
[mechanisms involved in the prolonged humoral immune response: behavior of aphthous fever virus].foot and mouth disease (fmd) is a widespread infectious disease affecting cloven-hoofed animals with severe economic consequences. animals infected with fmd virus (fmdv) develop an immunological status of immunity characterized by high titers of virus serotype-specific neutralizing antibodies (nab) which persist for at least 18 months. in contrast, currently inactivated virus vaccines elicit lower antibody response for shorter periods. protection against fmdv infection has been commonly related ...19968815460
prevalence of foot-and-mouth disease antibodies in dairy herds in the netherlands four years after vaccination.a total of 298 serum samples were collected from dutch cattle born in 1988 or before, and examined in the virus neutralisation test for antibodies against foot-and-mouth disease virus types a10 holland. o bfs, and c1detmold. all the cattle had been vaccinated at least twice during the annual vaccination programme, which stopped in 1991. antibody titres equal to or higher than the titre at which 95 per cent of the cattle would be expected to be protected against challenge, were found in 57 to 73 ...19968819202
serological and molecular analysis of serotype o foot-and-mouth disease virus isolated from disease outbreaks in india during 1987-91.foot-and-mouth disease virus (fmdv) type o outbreaks have been reported frequently in vaccinated cattle in india. twenty-five field isolates, recovered from outbreaks in vaccinated and unvaccinated cattle between 1987 and 1991, were analyzed in relation to the vaccine strain (r2/75) by complement fixation, serum neutralization and partial nucleotide sequencing of the vp1 gene. these sequences were compared with the viral sequences in genembl database. although the indian type o viruses were clos ...19968822633
serological study of type a indian foot-and-mouth disease virus isolates.the antigenic relationship of sixty type a foot-and-mouth disease (fmd) viruses isolated between 1968 and 1993 has been determined with reference to a post-vaccinal bovine serum produced against type a ind 17/82. a micro-neutralization test and elisa were used to compare isolates. analysis of the results indicated that there was a positive correlation between the data from the two methods. the study indicated that type a ind 17/82 had a broad immunogenic spectrum and could be considered as a can ...19958825299
emerging foot-and-mouth disease virus variants with antigenically critical amino acid substitutions predicted by model studies using reference of the major obstacles to the design of effective antiviral vaccines is the frequent generation of antigenic viral variants in the field. the types of variants that will become dominant during disease outbreaks is often unpredictable. however, here we report the genetic and antigenic characterization of emerging foot-and-mouth disease virus (fmdv) variants with antigenically critical amino acid substitutions predicted by model studies using reference viruses and monoclonal antibodies. the ne ...19968852403
antigenic analysis of type o foot-and-mouth disease virus in the persistently infected bovine.the antigenic profiles of serotype o strains of fmdv collected from the oropharynx of persistently infected cattle were defined with a panel of monoclonal antibodies (mab's) in an indirect antigen-trapping elisa. the mab profiling showed no significant loss of reactivity in two neutralising antigenic sites of persistent fmdv isolates collected over a period of eight months. early and late serum taken from a carrier animal showed similar neutralising activity against early and late carrier isolat ...19968856023
isotype-specific antibody responses to foot-and-mouth disease virus in sera and secretions of "carrier' and "non-carrier' cattle.isotype-specific antibody responses to foot-and-mouth disease virus (fmdv) were measured in the sera and upper respiratory tract secretions of vaccinated and susceptible cattle challenged with fmdv by direct contact or by intranasal inoculation. a comparison was made between cattle that eliminated fmdv and those that developed and maintained a persistent infection. serological and mucosal antibody responses were detected in all animals after challenge. iga and igm were detected before the develo ...19968870633
increase of murine splenic natural antibody-secreting cells after cyclophosphamide treatment.administration of a low sub-immunosuppressive dose of cyclophosphamide (cy) to naive mice induced a marked increase in the number of splenic cells forming natural antibodies against unrelated antigens such as foot-and-mouth disease virus, keyhole limpet hemocyanin, horseradish peroxidase, or bovine serum albumin, as determined by an enzyme-linked immunosorbent assay spot technique. these results suggest that in mice there exists a repertoire of b cells forming natural antibodies which is restrai ...19968906754
[the use of synthetic peptides for detection of antibodies against foot-and-mouth disease virus in the blood from convalescent animals].peptides were synthesized, which, according to theoretical analysis of the antigenic structure of protein vp1 of foot-and-mouth disease (fmd) virus types a, 0, and asia 1, corresponded to potential immunodominant protein sites. activities of the peptides were studied by solid-phase indirect radioimmunoassay on polyethylene film with purified immunoglobulins against intact fmd virus. virtually no cross reactions were observed. blood sera of cattle convalescent after fmd were tested with the fmd v ...19968999315
evaluation of a live-attenuated foot-and-mouth disease virus as a vaccine candidate.a variant of foot-and-mouth disease virus (fmdv) lacking the leader (l) coding region (a12-llv2) was previously constructed and shown to be less virulent in cattle than its wild-type parent (a12-ic). in this study, cattle were tested for their clinical and immunological responses to subcutaneous inoculation with a12-llv2 or a12-ic or to intramuscular vaccination with chemically inactivated a12-ic. five weeks postinoculation animals were challenged by intradermal inoculation in the tongue with a ...19979007062
development of tests for antibodies against foot-and-mouth disease virus in cattle milk.the liquid-phase blocking elisa (lpbe) and a specific isotype assay (sia) for bovine igg1 were modified to detect antibodies against fmdv isolate o1 manisa in cattle milk. samples from vaccinated animals were mostly indistinguishable from negative control cattle in the lpbe but 90% of milks from convalescent animals (which had also been vaccinated several times previously) gave positive results. the sia was able to detect 95% of cattle vaccinated up to 12 months previously, and 100% of the recov ...19979015288
the performance of southern african territories serotypes of foot and mouth disease antigen in oil-adjuvanted vaccines.the performance of selected oil adjuvants containing southern african territories (sat) serotypes of foot and mouth disease virus was assayed by testing antibody levels elicited in cattle, sheep and goats, and by testing protection of cattle on challenge. various oil adjuvant formulations were tested initially in cattle and guinea pigs, and compared with a standard alhydrogel and saponin-based (as) vaccine. a commercial double oil emulsion vaccine elicited higher antibody titres and a more prolo ...19969025141
evaluation of the presence and risk of foot and mouth disease virus by commodity in international trade.potential sources of foot and mouth disease (fmd) virus include semen from bulls, rams, goats and boars; embryos and ova from ruminants and pigs; meat and meat products and milk and milk products. the author discusses precautions to prevent the transmission of fmd via these commodities.19969025152
antiviral activity of crude extracts of guarea guidona.crude extracts of leaves and fruits of guarea guidona were tested for antiviral activity against pseudorabies virus and foot-and-mouth disease virus in the ib-rs-2 pig cell line and against bovine herpesvirus-1 (bhv-1) in the gbk bovine cell line. the highest nontoxic doses of extracts from fruits and leaves were 125 micrograms/ml and 500 micrograms/ml. respectively. crude extracts presented antiviral activity against pseudorabies virus with a decrease in virus titer of 3.0 log units at 500 micr ...19969033817
a large-scale evaluation of peptide vaccines against foot-and-mouth disease: lack of solid protection in cattle and isolation of escape mutants.a large-scale vaccination experiment involving a total of 138 cattle was carried out to evaluate the potential of synthetic peptides as vaccines against foot-and-mouth disease. four types of peptides representing sequences of foot-and-mouth disease virus (fmdv) c3 argentina 85 were tested: a, which includes the g-h loop of capsid protein vp1 (site a); at, in which a t-cell epitope has been added to site a; ac, composed of site a and the carboxy-terminal region of vp1 (site c); and act, in which ...19979060612
an analysis of foot-and-mouth-disease epidemics in the uk.there was a major epidemic of the foot-and-mouth-disease virus among cattle herds in the uk in 1967-68 which showed a very rapid early spread, a much slower later spread, and eventually infected 12% of herds in the core epidemic area. a simple discrete-time version of a susceptible-latent-infectious-removed epidemiological model is used to generate a set of estimates of the transmission rate. this parameter has high values over the first few days, then the values are lower and they subsequently ...19979080685
functional expression of a cattle mhc class ii dr-like antigen on mouse l cells.cattle dra and drb genes, cloned by reverse-transcription polymerase chain reaction, were transfected into mouse l cells. the cattle dr-expressing l-cell transfectant generated was analyzed serologically, biochemically, and functionally. sequence analysis of the transfected drb gene clearly showed showed that it was drb3 allele drb3(*)0101 , which corresponds to the 1d-ief-determined allele drbf3. 1d-ief analysis of the transfectant confirmed that the expressed dr product was drbf3. functional i ...19969110933
infectivity assays of foot-and-mouth disease virus: contact transmission between cattle and buffalo (bubalus bubalis) in the early stages of differences were observed between cattle and indian buffalo (bubalus bubalis) in terms of temperature, viraemia or virus replication in the pharyngeal area, during the acute phase of foot-and-mouth disease. like cattle, the indian buffalo became infected and excreted virus before any clinical signs of foot-and-mouth disease developed. the disease was transmitted from cattle to buffalo and vice versa, during the acute stage of infection, as if the animals had been of the same species, presumab ...19979123797
baculovirus expressed 2c of foot-and-mouth disease virus has the potential for differentiating convalescent from vaccinated animals.determining whether animals have been infected with foot-and-mouth disease virus or vaccinated is important because infected animals frequently become carriers of the virus, shed it intermittently and thus may be the source of new outbreaks of the disease. we had shown previously that the sera of convalescent animals contain antibodies to 2c, a highly conserved non-structural protein, whereas the sera of vaccinated animals do not. this is explained by observation that 2c is retained on the membr ...19979128860
dexamethasone inhibits virus production and the secretory iga response in oesophageal-pharyngeal fluid in cattle persistently infected with foot-and-mouth disease virus.cattle persistently infected with foot-and-mouth disease virus were treated with dexamethasone to suppress the immune system in an attempt to influence the level of virus recovery from oesophageal pharyngeal (probang) samples. twelve carrier cattle were assigned to one of three groups: control; 0.1 mg/kg dexamethasone; and 0.5 mg/kg dexamethasone. groups 2 and 3 were injected intramuscularly three times weekly for 3 weeks with dexamethasone between days 33 and 56 post-infection with foot-and-mou ...19979129595
foot-and-mouth disease virus-infected but not vaccinated cattle develop antibodies against recombinant 3ab1 nonstructural protein.foot-and-mouth disease (fmd) vaccines induce antibodies against structural and some nonstructural proteins present in vaccine preparations. to differentiate between fmdv-infected and vaccinated animals, we developed immunochemical assays capable of detecting antibodies against a fmdv nonstructural protein. recombinant nonstructural 3ab1 protein was expressed in e.coli and in insect cells and used to detect anti-3ab1 antibodies. elisa and western blot analysis showed that sera from cattle infecte ...19979170505
characteristic in vitro evolution pattern of foot and mouth disease virus a81/castellanos/arg/87.the in vitro evolution of foot and mouth disease virus (fmdv) a/81/castellanos/arg/87 (a/castellanos/87) was studied by partial biological and biochemical characterization of viral populations selected after 25 passages on secondary fetal bovine kidney cell monolayers. these passages were performed in the presence or absence of immune pressure exerted in the form of antiviral polyclonal serum. while the viral populations passaged in the absence of immune pressure acquired characteristics such as ...19979175254
total and isotype humoral responses in cattle vaccinated with foot and mouth disease virus (fmdv) immunogen produced either in bovine tongue tissue or in bhk-21 cell suspension cultures.the anti-foot and mouth disease virus (fmdv) serum antibody activity of protected and non protected animals immunized with inactivated fmdv originated in either bovine tongue tissue (bttv vaccines) or bhk-21 cell suspension cultures (bhkv vaccines) was evaluated. the results show that 80-100% of the bttv immunized and only 40-60% of the bhkv immunized animals with liquid-phase blocking sandwich elisa (lp elisa) serum titres of 1.5-1.7 u, were protected against the challenge with any of the four ...19979178462
tissue culture adaptation of foot-and-mouth disease virus selects viruses that bind to heparin and are attenuated in cattle.isolates of foot-and-mouth disease virus (fmdv) exist as complex mixtures of variants. two different serotype o1 campos preparations that we examined contained two variants with distinct plaque morphologies on bhk cells: a small, clear-plaque virus that replicates in bhk and cho cells, and a large, turbid-plaque virus that only grows in bhk cells. cdnas encoding the capsids of these two variants were inserted into a genome-length fmdv type a12 infectious cdna and used to produce chimeric viruses ...19979188578
[seroprevalence of viral infections in llamas (lama glama) in the republic of argentina].this study reports the seroprevalence of bovine viral infections in llamas (lama glama) in argentina. this is the first study made in the country including 390 llamas and testing antibodies against eight viruses. samples were collected from nine farms distributed in three different provinces: buenos aires, córdoba and jujuy. the samples were tested for antibodies against eight viruses known to infect cattle: bovine herpesvirus type 1 (bhv-1), bovine viral diarrhea virus (bvdv), bovine adenovirus ...19979229724
computer simulations to identify in polyproteins of fmdv ok1 and a12 strains putative nonapeptides with amino acid motifs for binding to bola class i a11 and a20 haplotype molecules.the computer program "findpatterns" was used to search fmdv- (ok1 and a12 strains) coded structural and nonstructural proteins for the availability of putative proteasome-generated nonapeptides with motifs reported for bola class i a11 and a20 haplotypes. these bola class i a11 and a20 nonapeptide motifs are identical to motifs of nonapeptides that interact with the peptide binding grooves of hla class i b35 and b27 haplotypes, respectively. the computer findpattern program was used to analyze t ...19979237351
antigenic features of foot-and-mouth disease virus serotype asia1 as revealed by monoclonal antibodies and neutralization-escape mutants.neutralizable antigenic sites/epitopes of serotype asial foot-and-mouth disease virus (strain ind63/72) were identified using monoclonal antibodies (mabs) and their neutralization-escape mutants. relative affinity/reactivity of the mabs for viral (both native and trypsin-cleaved) and subviral antigens in enzyme-linked immunosorbent assay (elisa) showed dominance of trypsin-sensitive and conformation-dependent neutralizable antigenic sites. characterization of neutralization escape mutants identi ...19979282776
nucleotide sequence of the p1 region of foot-and-mouth disease virus strain o1 has been shown that variation of antigenic site i in vp1 of foot-and-mouth disease virus (fmdv) plays an important role in the antigenic diversification of this virus. however, the o1 campos strain is able to efficiently cross-protect cattle against the o1 caseros strain, despite having a different sequence in the site i. in this paper we report and compare the p1 coding region for the capsid proteins of fmdv o1 caseros and o1 campos. the deduced amino acid sequence showed a total of 31 amino ...19979311571
plasmid dna encoding replicating foot-and-mouth disease virus genomes induces antiviral immune responses in swine.dna vaccine candidates for foot-and-mouth disease (fmd) were engineered to produce fmd virus (fmdv) particles that were noninfectious in cell culture or animals. the prototype plasmid, pwrm, contains a cytomegalovirus immediate-early promoter-driven genome-length type a12 cdna followed by the bovine growth hormone polyadenylation site. bhk cells transfected with this plasmid produced virus, but the specific infectivity of pwrm was much lower than that achieved with in vitro-generated rna genomes ...19979311823
antiviral activity of an extract from leaves of the tropical plant acanthospermum hispidum.incubation of the alphaherpesviruses pseudorabiesvirus (prv) and bovine herpesvirus 1 during infection of cell cultures with an extract prepared from the leaves of acanthospermum hispidum impaired productive replication of these viruses in a concentration-dependent manner whereas propagation of classical swine fever virus, foot-and-mouth disease virus and vaccinia virus was not affected. the 50% inhibitory concentration for cell growth (ic50) was 107 +/- 5 microliters/ml, and the concentration r ...19979330761
escape mutants of foot-and-mouth disease virus selected by monoclonal antibodies directed to a trypsin-sensitive neutralization epitope.five monoclonal antibodies (moabs) against indian reference/vaccine strain of foot-and-mouth disease (fmd) virus subtype a22 (ind17/77) and a guinea pig antibody against a synthetic peptide representing amino acids (aa) 136-151 of vp1 polypeptide of a22 virus were used in the study. all the antibodies either failed to react or showed a reduced reactivity with trypsin-treated (tt)-146 s virus particles in enzyme-linked immunosorbent assay (elisa), and could neutralize the infectivity of the refer ...19979385400
the non-structural polyprotein 3abc of foot-and-mouth disease virus as a diagnostic antigen in elisa to differentiate infected from vaccinated cattle.a diagnostic assay to differentiate antibodies induced by foot-and-mouth disease virus (fmdv) infection from those induced by vaccination was developed. the test is an indirect-trapping elisa which uses a monoclonal antibody to trap the non-structural 3abc-fmdv polypeptide expressed in e. coli. experimental and field sera from naive, vaccinated and infected cattle were examined. using the established threshold of 0.20 optical density units, the sensitivity of the assay was 100%, as all the exper ...19979413510
a similar pattern of interaction for different antibodies with a major antigenic site of foot-and-mouth disease virus: implications for intratypic antigenic variation.the three-dimensional structures of the fab fragment of a neutralizing antibody raised against a foot-and-mouth disease virus (fmdv) of serotype c1, alone and complexed to an antigenic peptide representing the major antigenic site a (g-h loop of vp1), have been determined. as previously seen in a complex of the same antigen with another antibody which recognizes a different epitope within antigenic site a, the receptor recognition motif arg-gly-asp and some residues from an adjacent helix partic ...19989420281
differentiating infection from vaccination in foot-and-mouth disease using a panel of recombinant, non-structural proteins in elisa.a profiling elisa was developed to detect antibody to the non-structural (ns) proteins lb, 2c, 3a, 3d, and the polyprotein 3abc, of foot-and-mouth disease virus (fmdv). the assay was used to examine panels of sera from naive cattle, and from experimentally infected or vaccinated animals. all sera from cattle experimentally infected with any of the seven serotypes of fmdv were positive for antibody to 2c, 3a, 3d and 3abc, and the majority were positive for lb. the three categories of sera could b ...19989491499
assessment using elisa of the herd immunity levels induced in cattle by foot-and-mouth disease oil vaccines.the development of a liquid-phase blocking sandwich elisa (lpbe) to measure antibodies (ab) produced in cattle with the o, a and c foot-and-mouth disease virus (fmdv) types of commercial vaccines used in argentina is described. the test was specific: 99% of naïve cattle sera (n = 130) gave titres below log10 = 1.2, and none had a titre above log10 = 1.5. comparative studies with serum neutralization test (snt) using sera from cattle which received one or more vaccine doses is reported. the overa ...19989500182
antigenic structure of foot and mouth disease virus type a22 (indian isolates).variations in foot and mouth disease virus are due to amino acid substitutions in the vp1, which is a major immunogen. analysis of this hypervariable region is essential to know the antigenic structure of the serotype and is necessary to select a suitable vaccine strain. fmdv type a22 is one of the four prevailing virus types for which the vaccine is used regularly. to understand the antigenic structure of this type, carboxy- terminal region of vp1 from two field isolates and vaccine virus were ...19989536655
foot-and-mouth disease virus virulent for cattle utilizes the integrin alpha(v)beta3 as its receptor.adsorption and plaque formation of foot-and-mouth disease virus (fmdv) serotype a12 are inhibited by antibodies to the integrin alpha(v)beta3 (a. berinstein et al., j. virol. 69:2664-2666, 1995). a human cell line, k562, which does not normally express alpha(v)beta3 cannot replicate this serotype unless cells are transfected with cdnas encoding this integrin (k562-alpha(v)beta3 cells). in contrast, we found that a tissue culture-propagated fmdv, type o1bfs, was able to replicate in nontransfecte ...19989557639
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
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
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
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
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
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
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
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
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
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
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
Displaying items 201 - 300 of 862