use of pre-coated immunoplates and freeze-dried reagents for the diagnosis of foot-and-mouth disease and swine vesicular disease by enzyme-linked immunosorbent assay (elisa).an indirect sandwich elisa is used by the world reference laboratory for foot-and-mouth disease for the diagnosis of foot-and-mouth disease virus and swine vesicular disease virus. the potential for supplying elisa 'kits' for diagnosis to other laboratories has been assessed by evaluating the reactivity of (a) immunoplates pre-coated with rabbit antisera to fmdv and svdv and (b) freeze-dried diluted reference antisera. immunoplates pre-coated using a sodium carbonate/hydrogen carbonate buffer re ...19882836457
new approaches to animal vaccines utilizing genetic engineering.control of infectious diseases in livestock is an important determinant in the success of a nation's effort to efficiently meet its need for animal products. genetic engineering offers many new options in the design of animal vaccines. monoclonal antibodies, dna cloning, recombination, and transfection are examples of techniques that facilitate innovative strategies in antigen identification, production, and delivery. this article reviews the use of genetic engineering in the production of vacci ...19882837363
use of peptides for immunization against foot-and-mouth disease.a peptide corresponding to the major immunogenic site of the protein vp1 of foot-and-mouth disease virus (fmdv) will elicit a protective neutralizing antibody response in guinea-pigs, cattle and pigs. the response is much greater when the peptide is presented as a linear dimer or tetramer and pigs receiving as little as 40 micrograms peptide have been protected against challenge infection. an even greater response is obtained when the peptide is presented as part of the core protein of hepatitis ...19882838987
failure of haematobia thirouxi potans (bezzi) to transmit foot-and-mouth disease virus mechanically between viraemic and susceptible 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 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
[possibilities of biophysicochemical antigen control in vaccine production using foot-and-mouth disease virus as an example (review)]. 19882840042
[the differentiation of foot-and-mouth disease virus strains of type o by serologic and biophysicochemical methods]. 19882840043
[the foot-and-mouth disease virus in ultrathin sections]. 19882840049
processing and assembly of foot-and-mouth disease virus proteins using subgenomic rna.recombinant dna clones were constructed in order to study the mechanisms of proteolytic processing and assembly in foot-and-mouth disease virus (fmdv). rna transcripts from these clones were synthesized using sp6 polymerase and translated in rabbit reticulocyte lysates. efficient translation occurred in the absence of all 5' untranslated sequences and processing of the structural proteins occurred in the presence of functional 3c protease which can function in trans. the specificity of 3c protea ...19882842438
modification of the leader protein (lb) of foot-and-mouth disease virus.translation of foot-and-mouth disease virus rna for extended periods in rabbit reticulocyte lysates results in the appearance of a previously undescribed protein. a protein with similar properties can also be detected in bhk cells at late times after virus infection. specific immunoprecipitation has shown that this protein (lb') is closely related to the smaller of the two leader proteins, lb, although it migrates with an apparently higher mr in sds-polyacrylamide gels. the conversion of lb to l ...19882842439
gene encoding capsid protein vp1 of foot-and-mouth disease virus: a quasispecies model of molecular evolution.a phylogenetic tree relating the vp1 gene of 15 isolates of foot-and-mouth disease virus (fmdv) of serotypes a, c, and o has been constructed. the most parsimonious tree shows that fmdv subtypes and isolates within subtypes constitute sets of related, nonidentical genomes, in agreement with a quasispecies mode of evolution of this virus. the average number of nucleotide replacements per site for all possible pairs of vp1 coding segments is higher among representatives of serotype a than serotype ...19882842792
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
a high proportion of anti-peptide antibodies recognize foot-and-mouth disease virus particles.synthetic peptides representing the amino acid sequence 141-160 of the structural protein vp1 of foot-and-mouth disease virus (fmdv) elicit virus-neutralizing antibody. absorption of anti-peptide sera with purified virus particles removed all detectable virus-binding and neutralizing activity, and reduced the elisa titres against the homologous peptide by 31-41%. the proportion of anti-peptide antibodies that also recognized virus was unaffected by whether the peptide had been inoculated free, c ...19882844657
qualitative and quantitative differences in the immune response to foot-and-mouth disease virus antigens and synthetic cross-immunization studies using foot-and-mouth disease virus (fmdv) antigens and a synthetic peptide, from a region within virus coat protein vp1, it has been shown that intact virus will prime the immune system for intact virus, virus subunits and synthetic peptide but not for disrupted virus. in contrast, peptide will prime for a response to peptide and virus subunits but not to intact virus or disrupted virus. furthermore, studies on antibody populations in anti-virus and anti-peptide ant ...19882844964
relationship of p220 cleavage during picornavirus infection to 2a proteinase sequencing.infection of hela cells by poliovirus results in an abrupt inhibition of host cell protein synthesis. it is thought that the mechanism of this inhibition involves proteolytic cleavage of the p220 component of the cap-binding protein complex, thereby causing functional inactivation of the cap-binding protein complex and preventing capped (cellular) mrnas from binding ribosomes. current data suggest that the viral proteinase 2a indirectly induces p220 cleavage via alteration or activation of a sec ...19882845133
leader protein of foot-and-mouth disease virus is required for cleavage of the p220 component of the cap-binding protein complex.suppression of host protein synthesis in cells infected by poliovirus and certain other picornaviruses involves inactivation of the cap-binding protein complex. inactivation of this complex has been correlated with the proteolytic cleavage of p220, a component of the cap-binding protein complex. since picornaviral rna is not capped, it continues to be translated as the cap-binding protein complex is inactivated. the cleavage of p220 can be induced to occur in vitro, catalyzed by extracts from in ...19882845152
[neutralization of foot-and-mouth disease virus o1 campos by antibodies induced by a synthetic peptide].foot-and-mouth disease virus (fmdv), contains a positive single-stranded rna enclosed in a protein capsid. previous studies have shown that a synthetic peptide located at the carboxyterminal end of vp1 of fmdv strain o1 kaufbeuren (o1k) at the amino acid positions 144-159, and coupled to klh was able to elicit high titers of neutralizing antibodies in guinea pigs and protected them against challenge with the homologous virus (8, 15). fmdv strain o1 campos (o1 ca) has a similar amino acid sequenc ...19882845477
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
prediction of three-dimensional models for foot-and-mouth disease virus and hepatitis a virus.atomic models of foot-and-mouth disease virus and hepatitis a virus have been predicted using amino acid sequence alignments with the known structures of mengo virus and human rhinovirus 14. the structural models are consistent with results of biochemical and immunological studies. the two viruses appear to have surface features exceedingly different than those of other picornaviruses. they also have large hydrophobic cavities within vp1 suggesting that it may be possible to inhibit their infect ...19882845659
coupling of foot-and-mouth disease virus to sheep red blood cells using tannic acid for immunological assays.a technique for coupling foot-and-mouth disease virus (fmdv) to tanned sheep red blood cells (srbc) is reported. different parameters influencing the procedure were studied. subtypes c2, c3, o1 and a24 were used as antigens, and guinea pig hyperimmune sera obtained were tested for specific antibody in passive hemagglutination (ph), passive hemagglutination inhibition (phi) and passive immune hemolysis (pil) assays. fresh and srbc stored in alsever's solution showed similar behavior when used as ...19882846600
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
[is the arg-gly-asp sequence the site for foot-and-mouth disease virus binding with cell receptor?].the arg-gly-asp sequence is being found in an increasing wide range of proteins with "adhesive" function. studying a series of synthetic peptide fragments of vp1 protein of fmdv, we showed that peptides containing the arg-gly-asp sequence, but not control peptides, inhibited fmdv binding to pig kidney cells in vitro, thus indicating participation of that sequence in fmdv binding to host cells.19882847760
opsonization-enhanced phagocytosis of foot-and-mouth disease virus.using isolated peritoneal adherent cells, in which monocytes and macrophages dominate, the uptake and destruction of foot-and-mouth disease virus (fmdv) was enhanced by the opsonization with mab of particular epitope specificity. this was seen under conditions in which virus infectivity was not neutralized, as determined by in vitro assay. activation of macrophages in vivo further enhanced the uptake of opsonized virus, presumably by increasing the percentage of phagocytosing cells. the enhanced ...19882847979
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
further characterization of an rna defective mutant of the foot-and-mouth disease this paper a further characterization of a foot-and-mouth disease virus (fmdv) temperature-sensitive mutant, ts 6, is described. this mutant presents a defective rna synthesis at non-permissive temperature (npt) by comparison to the wt capacity. however, a low level of viral rna synthesis (below 10%) was sufficient to achieve an almost normal protein synthesis including a normal pattern of protein cleavage. in addition, morphogenetic precursor particles, 14s and 75s, are formed, indicating th ...19882848384
crossover regions in foot-and-mouth disease virus (fmdv) recombinants correspond to regions of high local secondary structure.the rna genome of foot-and-mouth disease virus (fmdv) was analysed for the degree of inverted complementarity and thus potential secondary structure using the procedure of pustell and kafatos [nucleic acids res (1982) 10: 4765-4782]. regions of crossover in 42 fmdv recombinants [king et al. (1985) virus res 3: 373-384; saunders et al. (1985) j virol 56: 921-929] and regions lacking crossovers were assigned an average secondary structure score against which the number of observed recombinants was ...19882848475
serological and biochemical analysis of some recent type a foot-and-mouth disease virus isolates from the middle 1986 and 1987 foot-and-mouth disease virus (fmdv) serotype a was isolated from outbreaks of disease in saudi arabia and iran. selected virus isolates were antigenically distinct from the prototype a22 virus strain (a22/iraq/64), but were serologically related to each other. however, polyacrylamide gel electrophoresis showed that whilst the respective saudi arabian structural polypeptides were homogeneous, those from an iran isolate were distinct. direct sequencing of part of the p-1d (vp1) ge ...19882850938
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
[antigenic structure of the foot-and-mouth-disease virus. i. synthesis of protective peptides from the major immunogenic region of vp1 protein of foot-and-mouth virus type o1k].a series of overlapping peptides with the sequence of the immunodominant region of vp1 protein of fmdv strain o1k have been synthesized by the classical solution method. peptides were purified by standard methods and used for immunization of guinea pigs. it is shown that the 136-152 and 136-148 segments provide antiviral protection in guinea pigs, both in the free state and conjugated with an immunogenic carrier. results with uncoupled peptides indicated that these segments may form not only b-, ...19882852937
[antigenic structure of the foot-and-mouth disease virus. ii. synthesis of protective peptides from the major immunogenic region of vp1 protein of foot-and-mouth disease virus type a22].earlier we found that the immune response and antiviral protection from fmdv can be achieved by immunization with uncoupled fmdv peptides. in a search of approaches to animal protection from fmdv a22 strain we prepared a series of peptides corresponding to the putative antigenic determinants. synthetic 131-149 and 140-149 sequences afforded 50 to 80% protection, both in the free state and conjugated with keyhole limpet hemocyanin. we believe that the 140-149 segment is so far the smallest peptid ...19882852938
minimum number of cells required for reconstitution of a foot-and-mouth disease virus-carrier cell culture.a serial cell plating experiment has been designed to determine the minimum number of cells, isolated from a culture persistently infected with a virus, required to reconstruct the carrier state. for cell line c1-bhk-rc1, consisting of bhk-21 cells persistently infected with foot-and-mouth disease virus type c (isolate c-s8c1), more than 10(3) cells derived from one monolayer were needed to reinitiate a stable, fmdv-producing carrier culture. thus, the fmdv-bhk-21 cell system cannot be explained ...19882855980
foot-and-mouth disease virus capsid proteins vp0, vp1 and vp3 synthesized by "in vitro" translation are the major components of 14s particles.translation of foot-and-mouth disease virus rna in extracts of rabbit reticulocytes resulted in the synthesis and assembly of viral capsid protein into immature virion intermediate structures. the particles, which sedimented in the 14s zone of the sucrose gradient and contained only viral proteins vp0, vp1 and vp3 are believed to be pentameric associations of viral protomers.19852869654
comparative studies on growth of foot-and-mouth disease virus types 0 and asia 1 in bhk-21 razi cells.growth pattern of foot-and-mouth disease virus types 0 and asia 1 in bhk-21 razi cells was compared; while type 0 virus grew in high titre, asia 1 virus was produced in low titre. inhibition of host protein synthesis in type 0 virus-infected cells was more pronounced than in asia 1 virus-infected cells. foot-and-mouth disease virus type 0 infected cells showed higher lactic dehydrogenase activity when compared to asia 1 virus. a significant decrease in virus yield was observed when actinomycin d ...19862878583
liposome encapsulated subunit (vp1) and virion vaccines against foot-and-mouth disease.subunit vaccine prepared from vp1 protein of foot-and-mouth disease virus (fmdv) types 0 and asia 1 protected guinea pigs against fmd and also induced high levels of antibody. liposomes have been used as a safe and potent immunological adjuvant for fmd vaccines. vaccines prepared from inactivated virus types 0 and asia 1 encapsulated in liposomes protected guinea pigs against challenge with homologous virus and showed good antibody response in pigs on a small scale field trial.19872886019
genetic manipulation of major p-fimbrial subunits and consequences for formation of fimbriae.the influence of genetic manipulation of the structural genes coding for major p-fimbrial subunits on the formation of fimbriae in escherichia coli was studied. deletion of two regions that code for hypervariable parts of the p fimbrillin resulted in strong reduction or total absence of fimbria production. replacement of deleted amino acids by other amino acid residues restored the formation of fimbriae. the hypervariable regions may be important for biogenesis of fimbriae by imposing correct sp ...19882903858
role of langerhans cells in the infection of the guinea-pig epidermis with foot-and-mouth disease guinea-pig infected with foot-and-mouth disease virus (fmdv), langerhans cells in the foot pads increase in number and show viral antigens 24 hours post-inoculation, preceding appearance of virus in epithelial cells and vesiculation. this observation suggests that langerhans cells may be engaged in virus transport from the blood to the non vascularized epidermis.19852982360
radioimmunoassay for detection of vp1 specific neutralizing antibodies of foot and mouth disease virus.a solid-phase radioimmunoassay was developed for the detection of antibodies against a specific region of the vp1 protein of the a24 and 01 serotypes of foot and mouth disease virus. the antibody titers from the radioimmunoassay showed a positive correlation with neutralizing antibody titers determined by a mouse protection assay. the specificity of the assay resides in the peptide used as antigen. the assay is rapid, reproducible and does not require the use of whole virions.19852982892
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
sequence analysis of hepatitis a virus cdna coding for capsid proteins and rna polymerase.we report here the nucleotide sequence corresponding to two large regions of the hepatitis a virus (hav) genome. these comprise a sequence of 3274 bases corresponding to the 5' end of the genome, which includes the putative capsid protein region of this picornavirus, and 1590 bases corresponding to the 3' end of the genome, terminating in a 15-base poly(a) tract. these sequences revealed that hav had the characteristic genomic organization of picornaviruses: an open reading frame beginning appro ...19852984684
foot-and-mouth disease virus subtype a22 epizootic in assam. 19852984834
sequence variation in the gene for the immunogenic capsid protein vp1 of foot-and-mouth disease virus type a.the nucleotide sequences have been determined and compared from cloned cdna genes coding for the foot-and-mouth disease virus (fmdv) immunogenic capsid protein, vp1, from eight different a subtypes: a5 westerwald/58, a12 119ab (large plaque variant), a22 550 ussr/65, a24 cruzeiro brazil/55, a27 cundinamarca colombia/76, a32 venezuela/70, a venceslau brazil/76, and a argentina/79. we have also found sequence variations among different cdna clones of the a5 and a24 subtypes. there are regions of n ...19852986125
[binary ethyleneimine as an inactivator of the foot-and-mouth disease virus].experiments were carried out to inactivate f.m.d. viruses with the use of binary ethylene-imine. it was found that inactivation was optimal when the agent was used at the rate of 0.003 m for 18 hours at 26 degrees c. its neutralization in the virus suspension was carried out with 3 mm sodium thiosulfate. the inactivated f.m.d. viruses retained their complement-fixing and immunogenic properties. discussed are the advantages of using binary ethyleneimine as an inactivating agent as against other a ...19852986348
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
effect of salts and other agents on foot-and-mouth disease virus poly (u) polymerase activity.the activity of the purified poly(u) polymerase replication complex of foot-and-mouth disease virus was optimized when 100 mm nh4+ and either 0.75 mm al3+ or 1.0 mm fe3+ was added to the standard assay reaction mixture. zn2+ at concentrations of 10(-5) mm to 5 mm inhibited enzyme activity although all polymerases examined to date have contained zinc. mercaptoethanol and dithiothreitol inhibited polymerase activity despite the presence of cysteine residues in the viral induced polypeptide of the ...19852986581
nucleotide and amino acid sequence coding for polypeptides of foot-and-mouth disease virus type a12.the coding region for the structural and nonstructural polypeptides of the type a12 foot-and-mouth disease virus genome has been identified by nucleotide sequencing of cloned dna derived from the viral rna. in addition, 704 nucleotides in the 5' untranslated region between the polycytidylic acid tract and the probable initiation codon of the first translated gene, p16-l, have been sequenced. this region has several potential initiation codons, one of which appears to be a low-frequency alternate ...19852987518
establishment of cell lines persistently infected with foot-and-mouth disease virus.cell lines persistently infected with foot-and-mouth disease virus (fmdv) have been established by growth of bhk-21 (c-13) or ibrs-2 (c-26) that survived standard cytolytic infections with fmdv. they maintain cytoplasmic fmdv rna sequences, as shown by dot blot hybridization tests, using cloned fmdv cdna as probes. cell line c1-bhk-rc1 was derived by infection of cloned bhk-21 c1 cells and plaque-purified fmdv c-s8 c1. indirect immunofluorescence assays indicated the presence of fmdv antigens. i ...19852990100
evaluation of methods for chemically coupling foot-and-mouth disease virus to sheep red blood cells for immunological assays.six methods of chemically coupling proteins to red blood cells were evaluated for their effectiveness in coupling foot-and-mouth disease virus (fmdv) to sheep red blood cells. the coupling agents tested were potassium periodate, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (ecdi), chromium chloride, glutaraldehyde, bis-diazotized benzidine (bdb) and n-succinimidyl 3-(2-pyridyldithio) propionate (spdp). of these, only the coupling methods using bdb and spdp resulted in virus-red c ...19852991312
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
isolation and biochemical characterization of intertypic recombinants of foot-and-mouth disease virus.recombinants were isolated between two european serotypes (o and a) and between two of the most distantly related serotypes (o from europe and sat2 from africa) using appropriate ts mutants in an infectious centre assay. the recombinants were characterised by electrofocusing of their induced proteins and by rnase-t1 fingerprinting of their rna. the approximate location of the cross-over event in each recombinant was determined by sequencing the unique distinguishable o or a oligonucleotides and ...19852992184
sequence of the viral replicase gene from foot-and-mouth disease virus c1-santa pau (c-s8).the nucleotide sequence of the region including the viral replicase gene, the carboxy terminus of protein p18, and the 3'-extracistronic region of foot-and-mouth disease virus (fmdv) type c1-santa pau (c-s8) has been determined from previously cloned cdna fragments [villanueva et al., gene 23 (1983) 185-194]. the comparison with the corresponding gene segments of fmdv of serotypes a or o shows base substitutions in 7.2-8.6% of residues in the replicase gene with no insertions or deletions. this ...19852993105
alteration in antibody reactivity with foot-and-mouth disease virus (fmdv) 146s antigen before and after binding to a solid phase or complexing with specific antibody.this paper describes the reactions of a number of monoclonal antibodies produced against purified whole virions of foot-and-mouth disease virus in 3 different enzyme immunoassay systems. the first system used whole virus bound non-covalently to microplates; the second used whole virus trapped by a polyclonal antibody which was bound to microplates; and the third allowed the monoclonal antibodies to react with the whole virions in suspension (liquid phase) before trapping by the solid-phase-bound ...19852993421
analysis of the secondary structure of the poly(c) tract in foot-and-mouth disease virus rnas.sodium bisulphite modification of foot-and-mouth disease virus (fmdv) rna in solution indicates that the majority of the poly(c) tract in the rna is single-stranded in concordance with previous results with encephalomyocarditis virus rna. the reaction kinetics are biphasic; 60% of the cytidylic acid in the poly(c) tract reacts like synthetic poly(c), and the remainder with the kinetics of the cytidylic acid in the rest of the rna. the reactivity of the poly(c) tract with poly(i) indicates that i ...19852993483
structure of a human common cold virus and functional relationship to other picornaviruses.we report the first atomic resolution structure of an animal virus, human rhinovirus 14. it is strikingly similar to known icosahedral plant rna viruses. four neutralizing immunogenic regions have been identified. these, and corresponding antigenic sequences of polio and foot-and-mouth disease viruses, reside on external protrusions. a large cleft on each icosahedral face is probably the host cell receptor binding site.19852993920
conditions for proper formaldehyde inactivation of foot and mouse disease alhydrogel vaccines.the inactivation of fmdv by formaldehyde (fa) was studied under different conditions, both as free virus and (as in routine vaccine production) after adsorption of the virus to aluminium hydroxide gel (alhydrogel). in the latter case infectivity was monitored after elution of the virus from the gel by isopycnic ultracentrifugation of the virus-alhydrogel mixture in cscl. by this method good virus recoveries were obtained. adsorption of the virus to alhydrogel (without formaldehyde) did not reduc ...19852995172
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
an international collaborative study on foot and mouth disease virus assay methods. 2. quantification of 146s particles.workers in 11 laboratories in europe and one in north america participated in a collaborative study to assess the variability of a sucrose gradient procedure used for the quantification of foot and mouth disease virus (fmdv). to this end, a range of standards was distributed from one of the participating laboratories. a series of adenine preparations were used to assess the various spectrophotometers/uv monitors and it showed most to be accurate and linear in their responses. the fmdv and ms2 ri ...19852997228
immunological priming with synthetic peptides of foot-and-mouth disease virus.a sub-immunizing dose of a synthetic peptide corresponding to the amino acids 141 to 160 region of protein vp1 from foot-and-mouth disease virus (fmdv), serotype o1, coupled to keyhole limpet haemocyanin (141-160klh) has been shown to prime the immune system of guinea-pigs for an fmdv serotype-specific neutralizing antibody response to a second sub-immunizing dose of the same peptide. optimal priming required an interval of 42 days between the priming dose and the booster dose. no priming was ob ...19852997370
foot-and-mouth disease virus-induced rna polymerase is associated with golgi apparatus.electrophoretic analysis of the golgi apparatus isolated by differential centrifugation from radiolabeled cells infected with foot-and-mouth disease virus showed about 10 protein bands. the virus-induced rna polymerase was identified by immunoprecipitation and electron microscope staining procedures. pulse-chase experiments indicated that the polymerase passed through the golgi apparatus in less than 1 h.19852997481
early steps in fmdv replication: further analysis on the effects of chloroquine.we have previously demonstrated that chloroquine and nh4cl, two well-known lysosomotropic drugs inhibit foot-and-mouth disease virus (fmdv) replication. this fact points to the relevance of an acidic environment during fmdv penetration. in the present report, we show that chloroquine prevents the cell-mediated disruption of 140 s virions into 12 s particles. this dissociation, which resembles that caused by low ph in vitro, might be an initial uncoating step. furthermore, we demonstrated that a ...19852998059
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
two initiation sites for foot-and-mouth disease virus polyprotein in vivo.typically, the translation of eukaryotic mrnas into protein is initiated at a single site. however, we have recently shown that not one but two primary products, p20a and p16, are translated from the 5' end of the coding region of the genome of foot-and-mouth disease virus (fmdv). in this paper we show by partial protease digestion of these proteins that they differ only at their n termini, thus confirming the presence of two initiation sites for translation of fmdv rna. sequence analysis of two ...19852999308
recombination and oligonucleotide analysis of guanidine-resistant foot-and-mouth disease virus mutants.guanidine resistance (gr) mutations of foot-and-mouth disease virus were mapped by recombining pairs of temperature-sensitive mutants belonging to different subtypes. in each cross, one parent possessed a gr mutation. recombinants were isolated by selection at the nonpermissive temperature and assayed for the ability to grow in the presence of guanidine. from the progeny of three crosses, four different types of recombinant were distinguished on the basis of protein composition and rna fingerpri ...19852999445
multiple sites of recombination within the rna genome of foot-and-mouth disease virus.recombinant foot-and-mouth disease viruses were isolated from cells infected with a mixture of temperature-sensitive (ts) mutants belonging to different subtype strains. in order to select for recombination events in many different regions of the genome, crosses were performed between various pairs of mutants, with ts mutations in different regions of the genome. ts+ progeny were analysed by electrofocusing virus-induced proteins and rnase t1 fingerprinting of their rna. all but 5 out of 43 inde ...19853000107
[an optical method for the quantitative detection of antibodies to foot-and-mouth disease virus--initial results]. 19853000308
[behavior of foot-and-mouth disease virus in various density gradient media]. 19853000312
[development of a method for the quantitative determination of the immunizing antigen (140s) of the foot-and-mouth disease virus].attempts were made to work out a method for measuring the amount of the 140 s antigen in virus suspensions. early postinfection sera were obtained from guinea pigs against the productional strains of the foot-and-mouth disease virus which were used in the radial immunodiffusion test. the investigated virus suspensions were concentrated 50 to 200 times and were placed in a cscl gradient for gradient centrifugation. the 140 s antigen fractions obtained were titrated in a radial immunodiffusion tes ...19853002008
guanidine-selected mutants of poliovirus: mapping of point mutations to polypeptide 2c.sequence analysis of the genomic rna of interstrain guanidine-resistant and antibody-resistant variant recombinants of poliovirus type 1 mapped the resistance of mutants capable of growth in 2.0 mm guanidine hydrochloride to a region located 3' of nucleotide 4444. this region of the viral genome specifies the nonstructural protein 2c. the sequence of genomic rna encoding 2c from six independently isolated mutants resistant to 2.0 mm guanidine was determined. all six isolates contained a mutation ...19863003395
[experiments to purify and concentrate the foot-and-mouth disease virus].experiments were carried out for the purification and concentration of the foot-and-mouth disease virus. for the purpose the virus suspensions were treated with chloroform and 8 per cent polyethylene glycol. the precipitated virus was eluated with phosphate buffer (of ph 7.6) up to 1:100 of the initial volume. the concentrated virus was subjected to gradient ultracentrifugation on gradient of cscl. the fractions obtained were investigated through radial immunodiffusion reaction with early sera, ...19853004012
the duration of the foot-and-mouth disease virus carrier state in african buffalo (i) in the individual animal and (ii) in a free-living herd.the maintenance of a virus depends on a number of factors, including the duration of infectivity and the size of the available host population. in this work, foot-and-mouth disease virus was shown to persist in individual african buffalo (syncerus caffer) for up to at least five years; thus, the duration of infectivity is more than adequate to cover the normal periods between calving peaks. in a small isolated free-living population which varied from 30 to 100 buffalo, two immunological types of ...19853004803
bacterially expressed antigenic peptide from foot-and-mouth disease virus capsid elicits variable immunologic responses in animals.a fusion protein consisting of beta-galactosidase (gz) to which was attached at its n-terminus the amino acid sequence corresponding to residues 142-160 of the immunogenic protein vp1 of foot-and-mouth disease virus (fmdv) has been expressed in e. coli. a chemically synthesized section of dna corresponding to the amino acid sequence 142-160 was inserted into a vector (pxy410) designed to express fusion proteins with the carboxy terminal 1015 amino acids of gz. the hybrid protein immunopurified b ...19863005401
protective effect of interferon on infections with hand, foot, and mouth disease virus in newborn mice.the protective effect of interferon on infection with coxsackievirus type a 16 (ca-16) or enterovirus type 71 (ev-71) in newborn mice was examined. subcutaneous administration of murine interferon (muifn-alpha/beta) into the infected mice produced a protective effect against infection with ca-16 or ev-71. it was found that the time of administration of muifn was important in relation to the cycle of infection. protection was observed when muifn was given once daily for several days, from one day ...19863005425
characterization of foot-and-mouth disease virus gene products with antisera against bacterially synthesized fusion proteins.defined segments of the cloned foot-and-mouth disease virus genome corresponding to all parts of the coding region were expressed in escherichia coli as fusions to the n-terminal part of the ms2-polymerase gene under the control of the inducible lambda pl promoter. all constructs yielded large amounts of proteins, which were purified and used to raise sequence-specific antisera in rabbits. these antisera were used to identify the corresponding viral gene products in 35s-labeled extracts from foo ...19863005640
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
the sequence of foot-and-mouth disease virus rna to the 5' side of the poly(c) tract.the nucleotide sequence of foot-and-mouth disease virus (fmdv) rna to the 5' side of the poly(c) tract (s fragment) has been determined for representatives of the a and o serotypes of the virus. the two s fragments differ in length by five nucleotides (nt), with 367 nt for o1 compared with 362 nt for a10, due to a number of insertions/deletions. however, the two sequences show 86% homology. there are no conserved open reading frames (orfs). secondary structure predictions reveal a high degree of ...19853007298
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
a second protease of foot-and-mouth disease virus.foot-and-mouth disease virus (fmdv) genes are expressed as a polyprotein which is rapidly processed into the four primary cleavage products l, p1, p2, and p3. in secondary cleavage reactions, these are further processed into the mature proteins. the fmdv l protein is located at the n terminus of the polyprotein and is the first gene product released from the nascent polyprotein. for analysis of its biological function, the l gene was mutated by site-directed mutagenesis of cloned cdna. in vitro ...19863009894
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
protection of guinea pigs against local and systemic foot-and-mouth disease after administration of synthetic lipid amine (avridine) liposomes.injection of the synthetic lipid amine, avridine, in the form of liposomes, protected guinea pigs against the development of lesions from foot-and-mouth disease virus (fmdv) inoculated intradermally into the rear footpads. the animals were protected against the development of vesicles at the inoculation site as well as the systemic spread of virus. maximal protection was obtained after intracardial injection of 5-10 mg doses of liposomal avridine. lower doses yielded decreased protection. subcut ...19863010856
plaque enhancement effect of sodium thiosulfate for foot-and-mouth disease viruses.a plaque enhancement effect by the addition of sodium thiosulfate for foot-and-mouth disease viruses was demonstrated when this salt was incorporated in agar and in agarose overlay media. most of the mechanism is obscure, however, as one of the effects is that sodium thiosulfate seems to interact in a reversible manner against the plaque inhibitor action of neutral red in cellular cytoplasm. a plaque inhibitor contained in agar could be removed in some degree by the addition of this salt.19863012288
foot-and-mouth disease virus (fmdv) experimental infection: susceptibility and immune response of adult mice are susceptible to foot-and-mouth disease virus (fmdv) infection only under some experimental conditions. this paper report the results of pathogenesis studies on 4 different strains of mice (cf1, c3h, nih-nude, balb-c/j) infected with the cloned and uncloned 0(1)c strain of fmdv. high virus titers were detected in blood and pancreas 12-24 h after infection (p.i.); these persisted for up to 48 h p.i. in cf1 and balb-c/j mice and 72 h p.i. in the two other mouse strains. virus titers o ...19863014713
immune protection against foot-and-mouth disease virus studied using virus-neutralizing and non-neutralizing concentrations of monoclonal antibodies.monoclonal antibodies (mab) against sequential or conformational epitopes on foot-and-mouth disease virus (fmdv) passively protected neonatal syngeneic (balb/c) mice at dilutions at which they could not neutralize virus infectivity in vitro. the b2, d9, 1c6 and 4c9 mab, against the group 1 (sequential) and group 2 (conformational) epitopes, protected the mice at an antibody:virion molar ratio of between 38:1 and 84:1 (12-18 times lower than that required for neutralization of virus infectivity i ...19863015780
experimental infection of vampire bats with foot and mouth disease virus. 19863016350
detection of a genome-linked protein (vpg) of hepatitis a virus and its comparison with other picornaviral vpgs.the nucleotide sequence corresponding to the p3 region of the hepatitis a virus (hav) polyprotein genome was determined from cloned cdna and translated into an amino acid sequence. comparison of the amino acid sequences of the genome-linked proteins (vpgs) of other picornaviruses with the predicted amino acid sequence of hav was used to locate the primary structure of a putative vpg within the genome of hav. the sequence of hav vpg, like those of other picornaviral vpg molecules, contains a tyro ...19863018280
exposure of sheep to natural aerosols of foot-and-mouth disease virus.sheep taken individually and allowed to inhale air being drawn along a duct from a cabinet containing pigs acutely infected with foot-and-mouth disease virus for 10 or 15 minute periods were infected by doses as low as 10 tcid50 of virus. the most consistent and reliable indicators of infection were viraemia and seroconversion. the mean times from exposure to onset of viraemia, pyrexia and the appearance of vesicular lesions were 2.5, 3.8 and 4.7 days, respectively. neither the time from exposur ...19863020658
[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
an electroblotting technique for assessing the integrity of the major immunogenic protein in foot-and-mouth disease virus vaccines.a method has been developed whereby vp1, the major immunogenic protein of foot-and-mouth disease virus can be detected after electroblotting on nitrocellulose paper. proteins can be examined in unfractionated virus harvests and after formulation as aluminium hydroxide-adjuvanted vaccines. the limit of detection is approximately 10 ng of vp1 and up to 20 samples can be analysed simultaneously. the technique allows the integrity of vp1 to be examined in fully formulated vaccines.19863021799
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
the genome-linked proteins of aphthoviruses: specific immunoprecipitation of the three species detected on virus rna and identification of possible precursors.synthetic peptides have been made corresponding to the c-terminal portion of each of the three presumptive genome-linked proteins (vpgs) of foot-and-mouth disease virus type a10. antisera against each of these peptides efficiently precipitated only the homologous vpg, and the reactions were inhibited by prior absorption with homologous, but not heterologous synthetic peptide. the peptide antisera precipitated a number of proteins from infected cell extracts with mol. wt. of 100, 84, 56, 36, 27, ...19863023531
theiler's virus genome is closely related to that of encephalomyocarditis virus, the prototype cardiovirus.theiler's virus causes a persistent demyelinating infection of the mouse central nervous system. our study of the molecular mechanism of persistence led us to sequence 1925 nucleotides located at the 3' end of the viral genome. we observed extensive homologies between this region and the corresponding region of encephalomyocarditis virus, the prototype cardiovirus, and only some homologies with the 3' ends of foot-and-mouth disease virus, rhinovirus, and poliovirus genomes.19863023668
ribavirin cures cells of a persistent infection with foot-and-mouth disease virus in vitro.ribavirin (1-beta-d-ribofuranosyl-1h-1,2,4-triazole-3-carboxamide) eliminates foot-and-mouth disease virus from persistently infected cell cultures. the latter are 10-fold more sensitive to ribavirin than lytically infected cells. in treated cells no viral rna or proteins could be detected by dot-blot hybridization to cdna probes, virus and rna infectivity assays, or immunofluorescence. a potential application of the drug for the treatment of animals carrying the virus is suggested.19873023704
host cell modulation of foot-and-mouth disease virus procapsid synthesis.bhk21 (clone 13s) cells of high (bhk-sh) and low (bhk-sl) passage number were infected with foot-and-mouth disease virus (fmdv) subtypes a24, a25 and c3. while the amount of virus specific rna produced in bhk-sh cells was 25% of that in bhk-sl cells and the virion production was 27% (c3) to 53% (a24) lower, the synthesis of viral proteins was comparable, associated with an accumulation of procapsids in bhk-sh cells. the results suggest that changes in viral infection pattern with increasing bhk2 ...19863024386
further characterization of a morphogenetic mutant of the foot-and-mouth disease this paper we describe further characterization of a foot-and-mouth disease virus (fmdv) temperature-sensitive mutant, ts 139. this mutant was very sensitive to heat inactivation, suggesting that its viral particles are somehow altered. the electrophoretic analysis of ts 139 structural proteins indicated that vp2 has an altered mobility. furthermore, two known protein precursors of vp2, vp0 and p88, were shown to be altered, as was p64, which supports a vp2 precursor role for p64. the ts 139 ...19863026109
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
conformational alteration in foot-and-mouth disease virus virion capsid structure after complexing with monospecific antibody.a mechanism of neutralization of virus infectivity by antibody is described and related to the immune defences in vivo. the interaction of a particular monoclonal antibody with homologous foot-and-mouth disease virus alters the conformation of the virions to permit penetration of staining reagents. a consequence of this structural alteration is that the rna genome becomes susceptible to dissociation from the capsid proteins. this mechanism of virus neutralization is irreversible and therefore pr ...19873028937
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
subtyping of european foot-and-mouth disease virus strains by nucleotide sequence determination.the vp1-coding regions of foot-and-mouth disease virus strains from 18 recent european outbreaks and of 9 strains isolated more than 20 years ago and used in part as vaccines were determined by direct cdna sequencing. comparison of the sequences revealed that most of the isolated outbreak viruses are closely related to the vaccine strains used. isolates from the italian epizootic of 1984 to 1985 correspond, for example, to the vaccine strain a5 parma 62; the outbreak in 1984 in bernbeuren, feder ...19873033288
all foot and mouth disease virus serotypes initiate protein synthesis at two separate augs.translation of the foot and mouth disease virus genome in vitro and in vivo indicated that all seven serotypes initiate protein synthesis at two separate augs. sequence analysis of the region surrounding these augs has shown that the efficiency with which the initiating aug is recognized is dependent on the flanking nucleotides. however, in vitro, the major factor determining which aug is used is the concentration of mg2+.19873033601
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
challenging settled opinions in classic foot-and-mouth disease vaccine a previous study we challenged the generally accepted opinion that inactivation of fmdv by formaldehyde (fa) is an (unsafe) non-linear process. our data showed that under proper conditions inactivation will be linear without "tailing-off". for more than forty years two other fixed beliefs existed with respect to fmd vaccine preparation: virus must first be adsorbed to al(oh)3-gel before being inactivated. concentrations of formaldehyde are critical and must be within a very narrow range. unti ...19873034709
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