Publications

TitleAbstractYear
Filter
PMID
Filter
failure of haematobia thirouxi potans (bezzi) to transmit foot-and-mouth disease virus mechanically between viraemic and susceptible cattle.in 2 separate experiments the blood-feeding fly haematobia thirouxi potans (bezzi) failed to transmit foot-and-mouth disease virus when transferred from viraemic (log 2,6-log 4,3 mld50 or tcid50/ml) to susceptible cattle. each experiment involved 2 susceptible and 2 viraemic animals housed in separate stables and 2,000-4,000 flies of which most had fed on viraemic hosts 120 min prior to transfer. furthermore, only minimal quantities of virus were isolated from free-living flies captured on exper ...19882839809
the suitability of a rolled bhk21 monolayer system for the production of vaccines against the sat types of foot-and-mouth disease virus. i. adaptation of virus isolates to the system, immunogen yields achieved and assessment of subtype cross reactivity.in an examination of 34 southern african sat-type foot-and-mouth disease viruses, all but 1 attained satisfactory levels of infectivity within 6 passages in rolled bhk21 monolayer cell cultures. however, there were marked differences between adapted viruses with respect to the mass of immunogen (146s material) produced. several isolates which consistently produced levels greater than or equal to 2 micrograms/ml were identified. in cross neutralization tests using post-vaccinal sera, sat-1 and sa ...19882839810
a comparison of enzyme-linked immunosorbent assay, complement fixation and virus isolation for foot and mouth disease diagnosis.a total of 205 epithelial tissue samples were examined for the presence of foot and mouth disease virus by either the complement-fixation (cf) test, enzyme-linked immunosorbent assay (elisa) and/or by virus isolation in bovine thyroid or kidney cell cultures. the virus was isolated from 134 of the 201 (67%) specimens. samples, from which virus was isolated, were termed virus-positive samples. the cf test detected viral antigen in 30 (24%) of 123 virus-positive samples, whereas the elisa detected ...19882845633
a continuous bovine kidney cell line for routine assays of foot-and-mouth disease virus.a continuous bovine kidney cell line, lf-bk, arose from primary bovine calf kidney cells that survived infection with a temperature-sensitive mutant of foot-and-mouth disease virus. no virus was recovered after the first passage. cells of passage 48 were inoculated into two steers which remained healthy and did not develop neutralizing antibodies to the virus. the karyotype of cells of the 53rd and 87th passages was similar and revealed that the cells were markedly transformed. the modal number ...19882847400
rapid correlation between field isolates and vaccine strains of foot-and-mouth disease virus.antigenic relationships between field isolates of foot-and-mouth disease virus and available vaccine strains can be rapidly determined by elisa. the most suitable vaccine strain to control an outbreak caused by the field isolate can then be quickly identified. the classical method of subtyping strains of foot-and-mouth disease virus should be replaced with a nomenclature which describes the relationship between a strain and the most antigenically closely related vaccine strain.19882848376
single dilution elisa for detection of serum antibody to foot-and-mouth disease virus in cattle.a single dilution blocking elisa was developed and evaluated for measuring serum antibody to foot-and-mouth disease virus (fmdv). basic parameters of the assay were established and a positive-negative threshold determined from testing 176 specific antibody negative sera from australian cattle. sera collected from immunised animals in thailand were tested by elisa and virus-neutralisation (vn) tests and the results compared. a positive correlation between elisa and vn titres was recorded for each ...19882852874
indirect immunofluorescence and immunodiffusion tests in the detection of antibodies to foot-and-mouth disease virus.the antibody response detected by indirect immunofluorescence (iif) as well as that directed against 140 s and virus infection associated antigen (via), as detected by agar immunodiffusion, was studied in three mammal species susceptible to foot and mouth disease virus, after challenge with living virus, immunization and hyperimmunization with inactivated virus, and immunization followed by challenge. by spot indirect immunofluorescence, antibodies were detected only in animals undergoing an act ...19852983488
dose-response evaluation of a genetically engineered foot-and-mouth disease virus polypeptide immunogen in cattle.four groups of 9 cattle each were vaccinated with 10, 50, 250, or 1,250 micrograms of foot-and-mouth disease (fmd) virus a12 vp1 fusion protein that was produced in escherichia coli and emulsified in an oil adjuvant. the groups given the 10 and 50 micrograms of antigen were revaccinated at 15 weeks and were challenge exposed at 30 weeks; 5 of 9 and 7 of 9 cattle, respectively, were protected from fmd virus infection. the remaining 2 groups, vaccinated with 250 or 1,250 micrograms of antigen, wer ...19852986495
detection of foot-and-mouth disease virus antibody using counterimmunoelectrophoresis and serum neutralisation tests.a comparative investigation was made on the applicability, sensitivity and specificity of counterimmunoelectrophoresis (ciep) for the rapid detection of antibody to foot-and-mouth disease virus in cattle sera using as reference a standard serum neutralisation test. the ciep test was sensitive and exhibited a reasonable specificity.19852992139
buffalo in the northern natal game parks show no serological evidence of infection with foot-and-mouth disease virus.a total of 594 sera collected from buffalo (syncerus caffer) in the hluhluwe/umfolozi game reserve complex, ndumu game reserve and the eastern shores of lake st lucia were examined for antibody to sat 1, 2 and 3 types of foot-and-mouth disease (fmd) virus in neutralization tests. no neutralization of sat 2 or 3 viruses was exhibited by any of the sera tested at final dilutions greater than 10. a small proportion (2,9%) of sera neutralized sat 1 virus at dilutions up to 10, but these were conside ...19852995896
biochemical characterization of an aphthovirus type 0(1) strain campos attenuated for cattle by serial passages in chicken embryos.the biochemical properties of a virulent and an attenuated strain of foot-and-mouth disease virus (fmdv) type 0(1) campos (0(1)c) were compared in order to establish differences that could account for their altered biological functions. the avirulent strain (0(1)c-o/e) was derived from the virulent strain 0(1)c by serial passages in chicken embryos. analysis of the rnase t1-generated oligonucleotides of the viral rna through one- and two-dimensional (2d) gel electrophoresis (fingerprints) reveal ...19852998071
biochemical characterization of a foot-and-mouth disease virus strain attenuated for cattle. brief report.wild-type, virulent (a-24 cruzeiro subtype) foot-and-mouth disease virus (fmdv), a related attenuated strain and revertants of the attenuated strain were examined by titration on primary bovine kidney (pbk) and baby hamster kidney (bhk-21) cells, as well as, by infection of unweaned mice. wild type virus grew equally well in all three systems, whereas the attenuated strain had a titer 2-3 log lower in pbk cells than in the other 2 assays. within 9 successive passages in bhk-21 cells the attenuat ...19863006639
protection of cattle against foot-and-mouth disease by a synthetic peptide.a chemically synthesized peptide consisting essentially of two separate regions (residues 141 to 158 and 200 to 213) of a virus coat protein (vp1) from the o1 kaufbeuren strain of foot-and-mouth disease virus was prepared free of any carrier protein. it elicited high levels of neutralizing antibody and protected cattle against intradermolingual challenge by inoculation with infectious virus. comparative evaluation of this peptide with a single-site peptide (residues 141 to 158) in guinea pigs su ...19863008333
potential for the transmission of foot-and-mouth disease virus from african buffalo (syncerus caffer) to cattle.foot-and-mouth disease viruses of types sat 1 and sat 2 isolated from diseased cattle and carrier buffalo, either on the same farm or in the same ecological area within a short time of each other, were compared by t1 oligonucleotide mapping. no similarity was observed between the maps obtained, indicating that the different populations of virus were unique to each species and that no interspecies transmission had occurred.19863010415
[a hitherto unknown reaction pattern in vertebrate cells (riv). 2. the protective effect of riv particle preparations against foot-and-mouth disease in guinea pigs].further observations concerning the previously described riv-particles are reported. they were isolated from a diploid cell line of bovine origin, embryonal duck fibroblasts and bhk-21 cells. a protective effect against foot-and-mouth-disease virus in guinea pigs could be observed following inoculation with the riv-preparation of bovine origin. all 3 preparations isolated from the 3 cell lines showed immunologic cross reactions.19863020838
a new enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against foot-and-mouth disease virus. i. development and method of elisa.a liquid-phase blocking sandwich elisa has been developed for the quantification of antibodies against foot-and-mouth disease virus which may replace the virus neutralisation (vn) test. this test employs the incubation of a constant amount of antigen with a range of test serum dilutions in the liquid-phase before being assayed using a trapping elisa. thus it does not rely on the availability or growth of tissue culture cells. the assay is rapid and relatively simple to perform, reagents are used ...19863021854
a new enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against foot-and-mouth disease virus. ii. application.the liquid-phase blocking sandwich elisa has been evaluated for the serological study of antibodies against foot-and-mouth disease virus (fmdv). the titres recorded for sera from a population of more than 300 british uninfected, unvaccinated cattle which were examined against each of the seven immunologically distinct fmdv types were less than 1 in 40. a positive correlation between elisa and vn titres was recorded for sera either vaccinated or involved in outbreaks of fmdv. the overall regressi ...19863021855
peptide vaccine--a new approach to a safer foot-and-mouth disease virus vaccine.a synthetic peptide, of which the region of the major antigenic determinant of foot-and-mouth disease virus serotype o1k located on the coat protein vp1 consists, was coupled to different protein carriers. comparing the potency of the conjugates to elicit neutralising antibodies it has been shown that klh was the best carrier protein. using different amounts of peptide a (aa 144-aa 159) the dependence of neutralising antibody response on the amount of injected peptide has been demonstrated. pept ...19873032213
multiple variants in foot-and-mouse disease virus (fmdv) populations: the achilles heel for peptide and rec. dna vaccines?variants of type a10 fmdv were isolated by passage of virus in bhk-cells in the presence of a neutralizing anti-peptide serum or monoclonal antibodies. these variants which were no longer neutralized by the particular anti-peptide serum or monoclonal antibody were easily obtained from (crude) virus populations ("cattle" virus and bhk-adapted virus). the rapidity of isolation (in two or three passages) suggested that these variants are already present in normal virus populations. all (plaque puri ...19873034708
effect of lysosomotropic compounds on early events in foot-and-mouth disease virus replication.the effect of three lysosomotropic compounds, chloroquine, monensin and nh4cl, on the replication of foot-and-mouth disease virus (fmdv) type a12 was studied. viral replication was almost totally inhibited by 0.5 mm chloroquine, 50 microm monensin, or 25 mm nh4cl. monensin and nh4cl affected replication when added either before or within the first hour of infection. chloroquine, however, still inhibited viral replication when added up to 2.5 h after infection. assays of binding of radiolabeled v ...19873037820
antigenic comparison of foot-and-mouth disease virus serotypes with monoclonal antibodies.the capsid structures of the 7 serotypes of foot-and-mouth disease virus have been compared utilizing a series of neutralizing monoclonal antibodies which were previously shown to recognize at least 4 distinct epitopes on type a12 virus. a radioimmune binding assay using radioactively labeled antigens and the monoclonal antibodies revealed that certain conformation dependent epitopes are conserved among a subtypes, while some continuous epitopes are conserved among a subtypes as well as other fm ...19863026110
serologic survey of viral antibodies in the peruvian alpaca (lama pacos).sera from more than 100 alpacas (lama pacos) from the peruvian southern sierra were examined for antibodies to 8 viruses known to infect other domestic animals. on the basis of these serologic findings and previously published serologic or clinical data, it is now known that the alpaca can be infected with the following viruses: parainfluenza-3, bovine respiratory syncytial virus, bovine herpesvirus-1, bluetongue virus, border disease virus, influenza a virus, rotavirus, rabies virus, vesicular ...19873826854
isolation of variants during passage of a strain of foot-and-mouth disease virus in partly immunized cattle. 19654283920
influence of salts on foot-and-mouth disease virus.the effect of sodium and magnesium chloride in 1 and 2 m concentration at temperatures of 37 and 50 c on type c, strain 149, foot-and-mouth disease virus during storage for 6 days was studied. the exclusively passaged cattle strain and its tissue culture-adapted line were compared. preparations of the various chemicals and their concentrations were made directly in suspensions of the virus, which, together with untreated control virus suspensions, were stored at indicated temperatures and tested ...19664289623
[survival in cattle of the modified foot-and-mouth disease virus]. 19664296536
detection of foot-and-mouth disease virus antibodies. i. "passive" hemagglutination test.a passive hemagglutination test has been developed to detect and measure foot-and-mouth disease virus (fmdv) antibody by using glutaraldehyde as a coupling reagent. an optimal concentration of 10 to 40 mug of virus per ml with 0.25% glutaraldehyde at 25 c for 1 hr was established for the sensitization of sheep erythrocytes. a reaction time of 18 hr at 4 c or 2 hr at 37 c induced good agglutination in the presence of specific antibody. sensitization was carried out in phosphate buffer, whereas ag ...19704318573
foot-and-mouth disease virus in cattle and pigs: use of polyethylene glycol or dextran for purifying 19s gamma-m immunoglobulin from sera. 19714325971
detection of foot-and-mouth disease virus antibodies. ii. use of fractionated bovine antisera for improving the specificity of a "passive" hemagglutination test.because 7s immunoglobulin (ig) g antibodies of low type specificity were present in mixtures with highly specific 19s igm antibodies, many bovine antisera to foot-and-mouth disease virus (fmdv) type a(12), strain 119 cross-reacted with type o of fmdv and to some degree with type c in the passive hemagglutination (ha) test. after 19s igm antibodies were separated by density gradient centrifugation or precipitated with 4% (w/v) polyethylene glycol, the antigen could be determined with "block" ha t ...19714329433
further information on the survival of modified foot-and-mouth disease virus in cattle. 19704337797
the survival of foot-and-mouth disease virus in african buffalo with non-transference of infection to domestic cattle. 19744364599
the effect of repeated vaccination in an enzootic foot-and-mouth disease area on the incidence of virus carrier cattle.a comparison was made of the incidence of foot-and-mouth disease virus ;carrier' cattle in an unvaccinated enzootic area and an area where routine 6-monthly vaccination with an inactivated vaccine had been carried out for 3-4 years. the incidence of carriers in the vaccinated area was 0.49% as compared to 3.34% in the non-vaccinated area. the results indicate that, provided the immune status of the vaccinated herd is maintained at a level sufficient to prevent outbreaks of clinical disease and t ...19744370898
studies on the carrier state of cattle exposed to foot-and-mouth disease virus. 19665219023
further information on the persistence of infective foot-and-mouth disease virus in cattle exposed to virulent virus strains. 19665995671
serological and biochemical analysis of foot-and-mouth disease virus (serotype c3) isolated in argentina between 1981 and 1986.the evolution in the field is described for foot-and-mouth disease viruses belonging to serotype c3 in argentina between 1981 and 1986. during 1981 and 1982 only three isolations of this serotype took place, which showed minor serological and biochemical variations from the prototype strain c3 resende-brasil/55. at the beginning of 1983 an outbreak was detected in a restricted geographical region caused by strains which had important serological and biochemical differences from the prototype str ...19882844033
the effect of antiserum quality on strain specificity assessment of foot and mouth disease virus by the neutralization reaction.the factors affecting the virus strain specificity of antibody to foot an mouth disease virus prepared by a variety of protocols in several species were evaluated by neutralization tests. the time at which the serum was taken, the antigen dose given, whether or not revaccination had occurred and the animal species in which the sera were prepared, did not appear to affect the strain specificity of serum prepared to inactivated antigens when measured in neutralization tests, probably because of th ...19846090465
a rapid enzyme-linked immunosorbent assay for the detection of foot-and-mouth disease virus in epithelial tissues.a rapid double sandwich enzyme-linked immunosorbent assay (elisa) has been used for the identification and type differentiation of foot-and-mouth disease (fmd) viruses in epithelial tissue samples submitted for diagnosis from the field. no difficulty was experienced in the direct typing of freshly harvested epithelium from recently ruptured vesicles by the complement fixation (cf) test or elisa. the elisa was more sensitive and specific, but proved no more efficient than the traditional cf test ...19846093338
purification and immunogenicity of fusion vp1 protein of foot and mouth disease virus.a procedure has been developed to purify foot and mouth disease virus (fmdv) vp1 surface antigens from recombinant escherichia coli. the vp1 antigens are expressed as fusion proteins derived from the e. coli trp operon and vp1 surface protein of fmdv. the procedure is capable of recovering greater than 96% of the desired product at a purity of greater than 96%. the resulting antigens induce significant levels of virus-neutralizing antibody in guinea pigs and cattle as determined by a mouse prote ...19846099140
response to foot-and-mouth disease vaccines in newborn calves. influence of age, colostral antibodies and adjuvants.oil-emulsified (oe) and aqueous (aq) vaccines were prepared with the same batch of inactivated a24 8345 foot and mouth disease virus (fmdv). calves born to vaccinated dams did not respond to the aq vaccine 30 or 90 days post partum. when the oe vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. however, calves 30 or more days old responded like adult cattle to the oe vaccine. when the oe vaccine was used in colostral antibody-free calves 3-30 day ...19882828089
a micro-enzyme-lavelled immunosorbent assay (micorelisa) for the detection of foot-and-mouth disease virus antigen and antibody.the indirect technique of a micro-enzyme-labelled immunosorbent assay (microelisa) was standardized and found efficient in detecting the foot-and-mouth disease virus antigen in cell culture fluids, mice carcases and cattle tongue epithelium as well as the antibody titre of sera.19816112866
subtyping of foot-and-mouth disease virus by the micro-enzyme-labelled immunosorbent assay (microelisa).the micro-enzyme-labelled immunosorbent assay (microelisa) was used successfully for the subtyping of foot-and-mouth disease (fmd) virus strains recovered from field outbreaks. the rabbit anti-guinea pig globulin-peroxidase conjugate employed in the indirect microelisa has the advantage of being used with any of the seven types of fmd virus.19816112867
stimulation by heterotypic antigens of foot-and-mouth disease virus antibodies in vaccinated cattle.immunisation of cattle with foot-and-mouth disease virus failed to raise a level of antibody that provides protection against heterotypic challenge. further the 12s substructure, produced from the 146s particle, was ineffective in providing protection against challenge by homotypic virus. these findings suggest considerable antigenic differences in the virus serotypes and between the virus and its substructure. inoculation of homologous 12s and heterologous 1246s and 12s antigens into vaccinated ...19826179141
enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against foot-and-mouth disease virus. iii. evaluation of antibodies after infection and vaccination.investigations using a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (elisa) for the measurement of antibodies against foot-and-mouth disease virus (fmdv) in sera from sheep and from cattle are reported, and results compared with those obtained by virus neutralization (vn) tests. serum antibody titres in sheep after primary vaccination and in cattle challenged with a natural aerosol after vaccination were similar by elisa and vn. however, the antibody levels detected in sera o ...19873428376
heterogeneity of the polyribocytidylic acid tract in aphthovirus: biochemical and biological studies of viruses carrying polyribocytidylic acid tracts of different lengths.in this paper we report a study of a sample of foot-and-mouth disease virus carrying two polyribocytidylic acid [poly(c)] tracts of different lengths. by plaque purification in tissue culture, we isolated two populations of particles, one carrying the long poly(c) tract and the other carrying only the short homopolymer. the fingerprints of both viruses were indistinguishable from each other and from that of the virus present in the original sample, suggesting that the main difference between the ...19846088803
detection and quantification of igm, iga, igg1 and igg2 antibodies against foot-and-mouth disease virus from bovine sera using an enzyme-linked immunosorbent assay.a simple solid-phase enzyme immunoassay is described for the detection of antibody classes showing activity against foot-and-mouth disease (fmd) virus in bovine sera. the assay achieves a preliminary separation of the specific class of antibody from other serum proteins through immuno-adsorption to class-specific immunoglobulin-coated wells of micro-titre plates. the specific antibody is reacted with fmd virus, which is then detected by an enzyme-labelled anti virus igg.19816257779
identification of a protein kinase activity in purified foot- and-mouth disease virus.purified preparations of foot-and-mouth disease virus types a, o, and c contain a protein kinase activity which can transfer the gamma phosphate of [32p]atp to virion structural proteins vp2 and vp3 and exogenous acceptor proteins. utilizing protamine sulfate as an acceptor, the kinase activity can be demonstrated in disrupted virus but not in intact virus. the enzyme is heat labile with optimal activity at ph 7 or greater. serine residues of protamine sulfate were identified as the amino acid p ...19816268834
vesicular exocytosis of foot- and -mouth disease virus from mammary gland secretory epithelium of infected cows.foot-and-mouth disease virus particles were observed by electron microscopy in the cytoplasma of alveolar secretory cells of the bovine mammary gland after contact exposure of uninfected cows to pits with foot-and-mouth disease. virus, contained in membrane-limited vesicles, was released from the basal and peranuclear portions of the cells into the intracellular and extracellular spaces by an exocytotic mechanism similar to that of the release of th milk-fat globule. virus was released into the ...19816271913
cloned viral protein vaccine for foot-and-mouth disease: responses in cattle and swine.a dna sequence coding for the immunogenic capsid protein vp3 of foot-and-mouth disease virus a12, prepared from the virion rna, was ligated to a plasmid designed to express a chimeric protein from the escherichia coli tryptophan promoter-operator system. when escherichia coli transformed with this plasmid was grown in tryptophan-depleted media, approximately 17 percent of the total cellular protein was found to be an insoluble and stable chimeric protein. the purified chimeric protein competed e ...19816272395
observations on the stability of foot and mouth disease vaccine antigens.the 146s particle of the foot and mouth disease virus which is used as a vaccine antigen was found to be relatively stable when stored for prolonged periods at 4 degrees c. however, stored antigens of virus strains of the sat serotypes but not of a virus strain of the type o serotype became less thermostable at 37 degrees c following 4 degrees c storage. vaccines returned from the field 10 months after they were made were shown to contain significant amounts of 146s antigen of the o, a, sat 1 an ...19836099640
serological differentiation of foot-and-mouth disease virus on electron microscope grids coated with protein a and antibody.a serological technique using electron microscope grids coated with protein a and antiserum was able to detect foot-and- mouth disease virus particles in oesophageal-pharyngeal fluids from infected cattle without the need for prior concentration of the sample. the technique was adapted to differentiate serologically among foot-and-mouth disease virus types a, o and c with antigen-adsorbed sera. when grids were coated with heterotypic antigenadsorbed antisera, the homotypic antigen could be obser ...19816280815
sensitivity of seven different types of cell cultures to three serotypes of foot-and-mouth disease virus.the ability of bovine tongue origin foot-and-mouth disease virus serotypes a, o and c to replicate in seven different types of cell cultures was studied. primary and secondary calf thyroid cells were equivalent in susceptibility to bovine kidney cell cultures passaged up to five times. calf thyroid cells lost their susceptibility after two passages. cryopreserved bovine kidney cell cultures passaged three and four times were equivalent in susceptibility to sensitive calf thyroid and bovine kidne ...19826284329
immunosuppression in bovine trypanosomiasis: response of cattle infected with trypanosoma congolense to foot-and-mouth disease vaccination and subsequent live virus challenge.the primary and secondary antibody responses to foot-and-mouth disease virus vaccine were examined in cattle infected with trypanosoma congolense and the response of some of these animals to live foot-and-mouth disease virus challenge was assessed. infected groups of cattle had rather lower antibody responses than uninfected control cattle after primary vaccination but the antibody titres were not significantly depressed until after secondary vaccination. these levels remained depressed for the ...19826285433
foot-and-mouth disease virus: immunogenicity and structure of fragments derived from capsid protein vp and of virus containing cleaved vp.peptide fragments were obtained from the immunogenic capsid protein vp3, ca. 24 kilodaltons (kd), of foot-and-mouth disease virus type a12 119ab by three procedures: (1) spontaneous proteolysis of in virion vp3 in tissue cultures to produce a 15 kd peptide, designated s fragment; (2) trypsin treatment of purified virus to produce a 16 kg peptide, designated t fragment; and (3) cyanogen bromide cleavage of purified vp3 to produce a 13 kd fragment. following isolation and purification by gel elect ...19826287701
aspects of heat inactivation of foot-and-mouth disease virus in milk from intramammarily infected susceptible cows.in skim milk obtained from susceptible cows after intramammary and intravenous inoculation (primary infected milk), foot-and-mouth disease (fmd) virus type o1 was slower inactivated by heat treatment than virus that had been added to pre-exposure skim milk. residual virus infectivity in heated primary infected milk was more efficiently detected in bovine thyroid cell cultures than in secondary pig kidney (pk2) cell cultures. untreated primary infected milk was found to inhibit both fmd-virus and ...19806244342
long distance transport of foot-and-mouth disease virus over the sea.the conditions required for the transport of foot-and-mouth disease (fmd) virus in the atmosphere over long distances and in sufficient concentrations to cause infection in exposed animals are described. using these factors a series of 23 outbreaks of fmd in europe, where the original outbreaks were separated from later outbreaks by sea passage, have been investigated. the findings obtained support the hypothesis that under certain conditions the airborne transmission of fmd over a long sea pass ...19826278697
the influence of normal guinea-pig serum and tissue culture assay system on foot-and-mouth disease virus neutralisation.the inclusion of normal guinea-pig serum in neutralisation reactions involving foot-and-mouth disease virus (fmdv) increased the neutralisation titre and rate of neutralisation by guinea-pig antiserum derived from animals convalescent from fmdv. such inclusion had little or no effect on neutralisation involving guinea-pig antiserum collected early in infection or early or convalescent bovine antisera. higher neutralisation titres and more rapid neutralisation were found from assay in bovine thyr ...19836189669
physicochemical transformation of milk components and release of foot-and-mouth disease virus.possible mechanisms for protective roles of milk components on foot-and-mouth disease virus present in the milk of infected cows were examined. light scattering bands collected from ficoll-sucrose gradient fractions of skim-milk contained membrane-limited structures but these were non-infectious for bovine kidney cells. infectivity titres in buttermilk higher than those of the original cream or butter suggested association of virus with milk fat globules. increased infectivity titres in skim-mil ...19836302144
competition for cellular receptor sites among selected aphthoviruses.the competition between different types of aphthoviruses (foot-and-mouth disease virus [fmdv]) for receptor site utilization was determined. the southern african territories (sat) types of fmdv absorbed poorly to bhk-21 cells as measured by a radioactivity binding assay but grew to relatively high titers on these cells. on bk cells, however, all three sat types bound well and competed with each other for receptor sites. in addition, unlabeled fmdv types a12 and o1b were able to completely inhibi ...19826297430
an investigation into causes of resistance of a cloned line of bhk cells to a strain of foot-and-mouth disease virus.the reduced ability of foot-and-mouth disease virus (fmdv) strain asia 1 iran 1/73 to replicate in the cloned bhk cell line aa7 was not due to lack of virus attachment at the cell surface. instead, the main restriction in the viral growth cycle occurred during synthesis and processing of viral macromolecules, and/or during the earliest stages of their assembly. reduced efficiency of penetration and uncoating of virus attached to the cells may also have contributed to inhibition of virus replicat ...19836310850
immunogenicity of foot-and-mouth disease virus type o1 replicated in either monolayer or suspended bhk cell system.the efficacy of vaccines formulated from the 10th passage of foot-and-mouth disease virus (fmdv) type o1 in monolayer baby hamster kidney (bhk) cells and the 8th passage in suspension bhk cells was compared in steers. the vaccines were inactivated with ethylenimine, contained an equal amount of antigen and were emulsified in oil-adjuvant. six animals were vaccinated with each vaccine. during the challenge of immunity (91 days post-vaccination, dpv), one out of the six steers from the monolayer v ...19836297845
association of foot-and-mouth disease virus induced rna polymerase with host cell organelles.the localization of foot-and-mouth disease viral-induced rna polymerase has been determined in situ and in partially fractionated cell components by using polymerase antisera tagged with either peroxidase or ferritin. electron microscopic examination revealed the polymerase to be heavily concentrated on membranes of the smooth membranous vacuoles (smv) which are newly formed during infection and which were previously shown to be the site where newly synthesized viral rna appeared. polymerase ant ...19836313290
innocuity testing of foot-and-mouth disease vaccines. ii. aziridine-inactivated antigen produced in baby hamster kidney cells.methods for the testing of preparations of aziridine-inactivated foot-and-mouth disease virus for the absence of infective particles were studied. the system used for virus production, suspension cultures of baby hamster kidney cells, proved to be the most sensitive detection system for traces of infective virus as long as the 146s antigen concentration was below 1 microgram per 10(6) cells. above this level interference may mask the presence of non-inactivated virus. thus in a 1-1 suspension cu ...19836315737
aerosol exposure of cattle to foot-and-mouth disease virus.slight modifications of a small, plastic covered greenhouse provided a chamber for the exposure of cattle of all ages to aerosols of foot-and-mouth disease virus. particle size distributions of aerosols were 76% less than 3 microns, 17% 3-6 microns, and 7% greater than 6 microns immediately after the devilbis no. 40 nebulizer used was turned off and 90% less than 3 microns, 8% 3-6 microns, and 2% greater than 6 microns 20-30 min later. pharyngeal virus growth curves and viremia patterns correlat ...19836315813
a serological and biochemical study of new field isolates of foot-and-mouth disease virus type a in peru, 1975 to 1981.three foot-and-mouth disease virus type a isolates recovered from field outbreaks in the department of san martin, peru, during the period 1975 to 1981 were compared with each other, and the south american vaccine strains a24 and a27, by complement fixation (cf), virus neutralization (vn) and polyacrylamide gel electrophoresis (page). complement fixation and vn tests gave comparable results distinguishing the field isolates from each other and from the vaccine strains. analysis of the structural ...19836318421
concentration of foot-and-mouth disease virus in milk of cows infected under simulated field conditions. 19826292275
histological and histochemical characterisation of mammary gland tissue of cows infected with foot-and-mouth disease by contact exposure.foot-and-mouth disease virus was observed to replicate in secretory epithelial cells of bovine mammary gland alveoli as a result of systemic infection initiated by exposure to infected animals. viral antigens were demonstrated using fluorescent antibody and immunoperoxidase labelling techniques before the development of signs of clinical disease. in addition, labelled antigens were observed associated with cytoplasmic-like fragments in luminal membrane limited structures. histologically, lesions ...19836312518
correlation of surface and internal ultrastructural changes in cells infected with foot-and-mouth disease virus.the surfaces of primary and continuous line cell cultures displayed the same sequence of morphological changes during the course of infection with foot-and-mouth disease virus. these changes could be classified into four broad stages: i) cells were flattened, closely attached to one another and microvilli appeared, ii) cells rounded, microvilli began to disappear and the cells started to separate from one another by cytoplasmic strands, iii) cells were discrete, rounded structures and iv) cells ...19836321000
the thermal death time curve for foot-and-mouth disease virus contained in primarily infected milk.whole and skim milk obtained from cows after intramammary and intravenous inoculation with foot-and-mouth disease virus (primarily infected milk) were exposed to various temperatures ranging from 80 to 148 degrees c for various times ranging from 2.5 s to 27 min then tested for viral infectivity. the average pretreatment titre of the 53 lots of milk used was 10(5.9) plaque-forming units of virus per millilitre 10(3.7)-10(6.8)). a thermal death time curve was plotted using the data obtained. the ...19846330120
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
multiple homologies of oligonucleotide size exist between nucleic acids of picornaviruses.a semi-quantitative analysis of hybrid formation between restriction enzyme-generated subgenomic fragments of cloned cdna prepared from rna of foot-and-mouth disease virus (fmdv) strain o1k and radiolabelled rna from bovine enterovirus, bovine rhinovirus or mengo virus indicated that the hybrids were of oligonucleotide size. they were located in those parts of the fmdv o1k genome that code for the two capsid proteins vp3 and vp1 and the precursor protein p52 as well as at the 3' end. no hybridiz ...19836306155
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
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
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
bovine t cells preferentially recognize non-viral spacer epitopes in a putative fmdv vaccinal peptide.in 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
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
biochemical map of polypeptides specified by foot-and-mouth disease virus.pulse-chase labeling of foot-and-mouth disease virus-infected bovine kidney cells revealed stable and unstable viral-specific polypeptides. to identify precursor-product relationships among these polypeptides, antisera against a number of structural and nonstructural viral-specific polypeptides were used. cell-free translations programmed with foot-and-mouth disease virion rna or foot-and-mouth disease virus-infected bovine kidney cell lysates, which were shown to contain almost identical polype ...19846323757
detection of foot-and-mouth disease virus-infected cattle by assessment of antibody response in oropharyngeal fluids.the detection of foot-and-mouth disease virus (fmdv)-persistent carriers among convalescent ruminants is of paramount importance in the aftermath of a field outbreak. to this purpose, fmdv-specific antibody should be investigated first, since virus isolation procedures from such carriers are seriously constrained. the complexity of the overall picture may be compounded by possible emergency vaccinations in the affected areas at the beginning of the outbreak. in this case, it is suggested that mu ...19957699071
characterization of foot-and-mouth disease virus by monoclonal antibodies.monoclonal antibodies (mabs) were produced against foot-and-mouth disease (fmd) virus types o1 campos br1/58, a24 cruzeiro br1/55, and c3 indaial br1/71, which are the strains used for production of fmd vaccines in the majority of south american countries. within the library of mabs produced, a group was selected on the basis of their neutralizing titer in cell culture, protective titer in suckling mice, sensitivity to trypsin, and specificity for virus structural proteins. the mabs were utilize ...19937507329
using genetically engineered bacteria for vaccine production.we concluded from this and our earlier work that biosynthetically produced fmdv vp1-specific fusion proteins are effective vaccines. whether this method of vaccine production can be extended to many other immunogenic proteins from other organisms is not known. some problems that could be expected to occur with bacterially produced antigens are that the immunogenic site may not be properly exposed or the peptide sequence(s) within that site may not be able to form into the correct configuration. ...19836322643
comparative between-laboratory trials of the liquid-phase blocking sandwich elisa for the detection of antibodies to foot-and-mouth disease virus.fifty bovine serum samples were tested for the presence or amounts of antibodies to foot-and-mouth disease (fmd) virus serotypes a, o and c by the liquid-phase blocking sandwich elisa (lpb-elisa) using reagents prepared by the world reference laboratory for foot-and-mouth disease (wrl) in pirbright, u.k. twenty of the sera had been collected before extensive vaccination with a commercial inactivated trivalent fmd vaccine was ceased and the remaining thirty originated from animals which had not b ...19957716862
optimization of an in situ hybridization technique for the detection of foot-and-mouth disease virus in bovine tissues using the digoxigenin system.an in situ hybridization technique has been optimised for use on paraffin-embedded sections of tissues collected from cattle infected experimentally with foot-and-mouth disease virus type o1bfs. tissue was collected 5 days after infection by direct contact. in situ hybridization was carried out using an rna probe corresponding to a region of the 3d gene which codes for the rna polymerase, and labelled with digoxigenin. consistent, reproducible signal was detected within the epithelial layers of ...19957730440
sequences derived from the highly antigenic vp1 region 140 to 160 of foot-and-mouth disease virus do not prime for a bovine t-cell response against intact virus.although vp1 region 140 to 160 of foot-and-mouth disease virus (fmdv) is able to elicit neutralizing antibody in cattle, the protection against virus challenge that is conferred by peptide immunization is often poor. here, we show that bovine t cells primed with peptides derived from this region generally show no reactivity to intact fmdv. in contrast, t-cell epitope vp4[20-34] is able to prime for a virus-specific response.19957769713
detection and subtyping of foot-and-mouth disease virus in infected cattle by polymerase chain reaction and amplified vp1 sequencing.fast and accurate detection of foot-and-mouth disease (fmd) outbreaks is needed to limit spread of the disease by proper vaccination. the use of the polymerase chain reaction (pcr) has revolutionized the way in which viral diseases are diagnosed. sequence analysis of the amplified vp1 sequence can enable the classification of fmd virus detected in the morbid animal. pcr assays were carried out to identify the virus and its serotype in suspect animals from 2 outbreaks of fmd type o virus. sequenc ...19957779964
serial passage in tissue culture of mixed foot-and-mouth disease virus serotypes.the foot-and-mouth disease (fmd) virus field specimen sau/8/88 was previously shown to consist of a mixture of o and asia 1 serotypes [15]. in this study, plaques representing the o and asia 1 components isolated from the original epithelial virus suspension were used to construct mixtures of known ratios, and these were serially passaged in tissue culture. after each passage, the ratio of o to asia 1 virus was calculated. the two virus populations were shown to be cycling through time. this cyc ...19957794118
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
characterization of an acid-resistant mutant of foot-and-mouth disease virus.a foot-and-mouth disease virus mutant which is stable at ph 6.4 has been isolated from a virus of serotype a. in contrast to the parent (p) virus, which gave a mixture of large and small plaques in bhk21 cells and in a bovine kidney cell line, the acid-resistant (ar) virus gave small plaques which did not increase markedly in size after 24 hr. the infectivity titer of the acid-resistant virus was about 100-fold lower in suckling mice than in bhk21 cells, whether the inoculation was made intraper ...19957831827
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
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
[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
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
Displaying items 101 - 200 of 862