cultivation of foot and mouth disease virus in bovine leukocyte cultures for use in the complement fixation test.bovine leukocyte cultures achieved good growth after 72 hours of cultivation. foot-and mouth disease (fmd) virus type 0 multiplied in such cultures to a titre of 10(6) tcid50/0.1 ml. the cell culture-grown virus was found to be suitable for the complement fixation test (cft) after purification and concentration with calcium phosphate.19769808
[several criteria of evaluation of foot-and-mouth disease virus reproduced in cell cultures in suspension].the study of the plaques produced by viruses asia and o1 reveals different properties which may depend on the virus or on the cell or its method of culture. antigenic differences and subsequent immunological differences correspond to differences in plaques. on the other hand, the cell line in suspension evolves both in its morphology and its receptivity during the passages. all these variations imply the observations of quantitative and qualitative criteria of evaluation in order to prepare vacc ...197671255
production, isolation, and partial characterization of three foot-and-mouth disease virus temperature-sensitive mutants.three high temperature-sensitive (ts) mutants of foot-and-mouth disease virus were characterized by their relative abilities to grow at 33 or 38.5 c, to kill infant mice, to infect guinea pigs, and to produce foot-and-mouth disease in steers. mutants ts-24 and ts-42 did not grow at 38.5 c; both may have produced considerable quantities of noninfectious virus particles at 33 c. a third mutant, ts-22, appeared "leaky" because it multiplied to a limited extent during prolonged incubation at the non ...1975166915
cross-reactions of normal bovine serums to foot-and-mouth disease virus in plaque-reduction neutralization and radial immunodiffusion.serums from 150 cattle with no known exposure to foot-and-mouth disease (fmd) virus were tested by both the plaque-reduction neutralization (prn) technique and the radial immunodiffusion (rid) technique to evaluate the significance and the extent of cross-reactions in these tests. serums from 30 cattle from each of 5 locations were tested against representative viruses of each of the 7 types of fmd virus. high levels of cross-reactions with both the rid and prn techniques were found in serums of ...1975167625
growth of foot-and-mouth disease virus in the upper respiratory tract of non-immunized, vaccinated, and recovered cattle after intranasal inoculation.non-immunized, vaccinated, and recovered cattle were inoculated intranasally with various doses of foot-and-mouth disease virus. samples of oesophageal-pharyngeal (op) fluid were taken periodically for up to 7 days after inoculation and virus titres of these samples were plotted as pharyngeal virus growth curves. in non-immunized cattle, the length of the lag period and of the growth period were inversely proportional to the dose of virus given. maximum titres were observed when clinical signs w ...1976180177
[local interferon production in cattle after intranasal infection with avirulent ibr/ipv virus and its effect on a subsequent infection with foot-and-mouth disease virus]. 1976183421
survival of foot-and-mouth disease virus in cheese.persistence of foot-and-mouth disease virus during the manufacture of cheddar, mozzarella, camembert cheese prepared from milk of cows experimentally infected with the virus was studied. cheese samples were made on a laboratory scale with commercial lactic acid starter cultures and the microbial protease marzyme as a coagulant. milk was heated at different temperatures for different intervals before it was made into cheese. food-and-mouth disease virus survived the acidic conditions of cheddar a ...1976184130
a foot-and-mouth disease vaccine for inactivated vaccine containing purified foot-and-mouth disease virus type o1, strain brugge, emulsified with incomplete freund's adjuvant was studied in swine. the antigen mass ranged from 0.02 to 416 mug in 0.25 ml of vaccine. at 90 days postinoculation (dpi) 33 to 100% of the swine which had been inoculated with 0.72% mug or larger amounts of antigen were protected against challenge. there was little protection at 182 dpi although the neutralizing titers obtained with 2.9, 34.6 and 416 mug ...1976187292
[use of indirect complement fixation test for studying foot and mouth disease virus].the indirect complement-fixation test was used in experiments for the subtype differentiation, and with the agar gel diffusion and the serum neutralization test was studied the immunity in cattle that had already recovered from foot-and-mouth disease or were immunized against the disease. it was found that the indirect complement-fixation test is instrumental in the demonstration of the antigenic differences between the foot-and-mouth viruses. comparative experiments have shown that the indirect ...1976189484
pathogenesis of foot-and-mouth disease: clearance of the virus from the circulation of cattle and goats during experimental viraemia.viraemia is an important aspect of the pathogenesis of infectious diseases, but the mechanisms of entry and removal of virus from the vascular system particularly in natural hosts are poorly understood. the results of this study showed that the clearance of foot and mouth disease virus (fmdv) from the circulation of cattle and goats followed the general rules for the clearance of inert particulate materials and other viruses from the circulation. high doses of infused fmdv were cleared less effi ...1976185289
cross reaction between bovine enterovirus and south african territories i5 foot-and-mouth disease virus.a bovine enterovirus (e76t) isolated from a 2-year-old bull produced serologic cross reactions to south african territories (sat) i5 foot-and-mouth disease virus when inoculated into guinea pigs and cattle. cross-reacting serum titers to sat i5 virus of 1:320 by the plaque-reduction neutralization test and 1:20 by the radial immunodiffusion test occurred in 2 steers after they were inoculated with the e76t virus. in 1 steer, maximal cross-reacting titers appeared related to a 2nd exposure to the ...1978204230
cross reactions of normal bovine sera with foot-and-mouth disease virus: incidence, duration, and effect of shipping stress.serum samples were obtained from 30 hereford steers in an area known to be free of foot-and-mouth disease (fmd) viruses as follows: before shipment and 4 times during a 70-day period after shipment; the sera were tested for the presence of cross-reacting antibody to various viruses. percentages of sera containing cross-reacting antibody to fmd virus detected by the plaque-reduction neutralization and the radial immunodiffusion techniques were higher for the fmd viruses asia and sat i5 than for t ...1978206170
excretion of foot-and-mouth disease virus in oesophageal-pharyngeal fluid and milk of cattle after intranasal infection.the virus growth in the pharyngeal area and the virus excretion in milk of susceptible and vaccinated dairy cows after intranasal instillation of foot-and-mouth disease (fmd) virus type o1 were examined. ten vaccinated cows were purchased through a market. of these, nine had delivered their first calf. the cows were inoculated 2-9 months after having received the last dose of vaccine. all vaccinated cows resisted the intranasal challenge. the virus multiplied in the pharyngeal area but, compared ...1978215675
foot-and-mouth disease virus typing by complement fixation and enzyme-linked immunosorbent assay using monovalent and polyvalent indirect "sandwich" enzyme-linked immunosorbent assay (elisa) using polyvalent and monovalent antisera was compared with the 50% complement fixation (cf50) test for the detection of foot-and-mouth disease (fmd) o, a, and c virus types. elisa was more sensitive than cf50 tests when polyvalent antisera were used for detecting the 3 types of virus in epithelial samples, whereas elisa using monovalent antisera was the least sensitive technique. the elisa performed with polyvalent antisera was 9 t ...19921325192
effect of heat on foot-and-mouth disease virus (fmdv) in the components of milk from fmdv-infected cows.foot-and-mouth disease virus (fmdv) survived in skim milk, cream and the pelleted cellular debris components of milk obtained from fmdv-infected cows after pasteurization at 72 degrees c for 0-25 min. virus was recovered from whole milk of infected cows after that milk was heated at 72 degrees c. for 5 min. and from the skim milk component after it was heated at the same temperature for 2 min. evaporation of the whole milk samples after they were heated at 72 degrees c. for 3 min. did not inacti ...1976185284
[protection from foot-and-mouth disease virus in naturally-susceptible animals by a linear polymer of a synthetic peptide].linear polymer of a peptide corresponding to the fragment 142-155 of the foot-and-mouth disease virus a22(550) protein (vp1) was synthesized. whereas the monomeric peptide was only slightly immunogenic, the polymer induced virus-neutralizing antibodies in rabbits and protected 100% guinea pigs. sheep vaccinated once and cattle vaccinated twice were stable against infection with the homologous virulent foot-and-mouth disease virus.19911665331
antibody response of tropical range cattle to foot-and-mouth disease virus. i. comparison of three tests. 1976198305
an evalutation of some methods of assay of foot-and-mouth disease antigen for vaccines.the relative merits of various in vitro assay systems for the measurement of the quality and quantity of foot-and-mouth disease virus vaccine antigen will be discussed. the assay systems include : viral infectivity, complement fixing activity, particle counts, radial diffusion titre and single radial haemolysis titre. the predictive value of the tests for the immunogenicity of the final vaccine product will be evaluated against the results of 50% protective dose titres determined in guinea pigs ...1976198302
foot-and-mouth disease: detection of antibodies in cattle sera by blocking elisa.a blocking elisa was developed for the detection of antibodies to foot-and-mouth disease virus sat1, sat2 and sat3 and for the quantification of antibodies on a single dilution of serum. the avidin-biotin system was used. the test was compared with the liquid-phase elisa executed at the world reference laboratory for foot-and-mouth disease. it was found to have favourable logistics and combined high specificity with high sensitivity. the quantitative test using a single dilution of serum was res ...19921333673
modified-live infectious bovine rhinotracheitis virus vaccine expressing monomer and dimer forms of foot-and-mouth disease capsid protein epitopes on surface of hybrid virus particles.modified-live, attenuated infectious bovine rhinotracheitis (ibr) hybrid virus vaccines have been constructed by inserting in the major ibrv glycoprotein giii gene chemically synthesized deoxyribonucleotide sequences encoding the bovine growth hormone signal sequence and monomeric or dimeric forms of the foot and mouth disease virus (fmdv) vp 1 epitope sequences. the foreign dna sequences were inserted at the n-terminal end of the ibrv giii coding sequence and were driven by the ibrv giii promot ...19911718244
detection and localization of single-base sequence differences in foot-and-mouth disease virus genomes by the rnase mismatch cleavage method.the rnase mismatch cleavage method was examined for its efficiency of indicating single-base sequence differences in the capsid protein-coding regions of different foot-and-mouth disease virus subtype o1 strains. the method was found suitable for indicating such differences. rnase a as well as rnase t1 contributed to substrate conversion. examples for the cleavage of eleven different single-base mismatches in rna double-strands are now known. all virus genomes found to differ from each other exh ...19911664431
antigenic stability of foot-and-mouth disease virus variants on serial passage in cell culture.two neutralizing monoclonal antibody (mab)-resistant variants selected from an isolate of foot-and-mouth disease virus (fmdv) type a5 were repeatedly passaged in cell culture and monitored for susceptibility to neutralization by the selecting mab. a variant isolated with a mab to a conformational epitope (1-og2) lost resistance in 20 passages, while a variant isolated with a mab to a linear epitope (1-ha6) persisted for 30 passages. in both cases, the virus population emerging after passage was ...19911645803
enhancement of the immune response elicited with foot-and-mouth disease virus vaccines by an extract of the mycobacterium sp. wall.the immunomodulating effect of an extract of the cell wall of mycobacterium sp. (wsf, vetrepharm inc., london, canada) in foot-and-mouth disease virus inactivated vaccines was tested in a murine model. the duration of immunity, protection, stimulation of immunocompetent cells acting on the long-lasting secondary response and possible tissue damage were examined. the incorporation of 10 micrograms wsf into aqueous and oil vaccines induced a high and long-lasting specific antibody response. the ne ...19911667346
rapid and sensitive detection of foot-and-mouth disease virus in tissues by enzymatic rna amplification of the polymerase detection of foot-and-mouth disease (fmd) virus from infected bovine and porcine tissue was investigated using a modified polymerase chain reaction (pcr) technique. a high degree of conservation was found in the genomic region coding for the viral rna polymerase among the seven fmd viral (fmdv) serotypes. an oligomeric primer pair and probe were constructed from consensus sequence data within this area. first strand cdna was synthesized using random hexamers and moloney mulv reverse trans ...19911666635
synthetic peptides against foot-and-mouth disease--immunization with vp1-peptides of type o1-kaufbeuren.coupled synthetic peptides, representing the sequences of amino acids 130-160, 141-160 and 145-160 of foot-and-mouth disease virus o1k protein vp1, induced virus-binding and virus-neutralizing antibody response in guinea pigs, rabbits, and pigs. we also detected antibody response in guinea pigs after immunization with uncoupled peptides and in cattle with 21 aa-peptide-keyhole-limpet hemocyanin (-klh). the best results were obtained from 21 aa-peptide-klh and 31 aa-peptide with or without klh or ...19901966360
a study on the immune response of sheep to foot and mouth disease virus vaccine type 'o' prepared with different inactivants and adjuvants.foot and mouth disease virus (fmdv) type 'o' was inactivated either with formaldehyde or binaryethyleneimine (bei). vaccines were prepared with inactivated virus incorporating aluminum hydroxide gel or mineral oil as an adjuvant. the antibody response in sheep was monitored by serum neutralization and elisa test for a period of six months. significant difference in antibody response was not observed between vaccines inactivated with formaldehyde or bei. on the other hand significant difference i ...19921364024
proliferative lymphocyte responses to foot-and-mouth disease virus and three fmdv peptides after vaccination or immunization with these peptides in cattle.we studied proliferative responses of bovine t lymphocytes to foot-and-mouth disease virus (fmdv) serotypes a, o and c as well as to three peptides including the two major b-cell epitopes of fmdv (vp1[141-156] and vp1[200-213]). peripheral blood mononuclear cells (pbmc) from cattle previously vaccinated with monovalent vaccine responded to both homotypic and heterotypic virus strains. of 14 fmdv-specific bovine t-cell clones, which were prepared from pbmc of an animal vaccinated with the trivale ...19921349300
heterotypic recognition of foot-and-mouth disease virus by cattle lymphocytes.lymphoproliferation against foot-and-mouth disease (fmd) virus was examined using peripheral blood mononuclear cells from vaccinated cattle. ten weeks after revaccination the optimum conditions for proliferation were obtained with 1 microgram/ml of purified virus after 5 to 6 days in culture. this contrasted with the response at 20 months post-revaccination, when the response required less antigen and showed a peak response after 3 to 4 days in culture. proliferation was specific for fmd virus, ...19901689767
modifications of the 5' untranslated region of foot-and-mouth disease virus after prolonged persistence in cell culture.the nucleotide sequence of the 5'-untranslated region (5'utr) of the genome of foot-and-mouth disease virus (fmdv) r100, rescued after 100 passages of persistently infected bhk-21 cells, has been compared with that of the parental fmdv c-s8c1. the nucleotide sequence divergence between the two viruses in heteropolymeric regions is 1%. the few mutations located at the 5'-most terminal region (s fragment) and at the internal ribosome entry site (ires) do not appear to affect significantly the tigh ...19921335672
changes in mononuclear peripheral blood cells in cattle with foot-and-mouth disease.the percentages and absolute numbers of mononuclear peripheral blood cells (mnc) were studied in vaccinated (vac) and non-vaccinated (control) cattle, challenged with foot-and-mouth disease virus (fmdv). all vac cattle but none of the controls resisted challenge. cell populations were studied immediately before and one week after challenge, by direct and indirect immunofluorescence, using polyclonal and monoclonal antibodies against different bovine markers. total b-lymphocytes, as assessed with ...19921347666
characterization and immune response of a protein produced by a cdna clone of foot and mouth disease virus, type asia 1 63/72.a 0.9 kb double stranded cdna of foot and mouth disease virus (fmdv) type asia 1, 63/72 was cloned in an expression vector, pur222. a protein of 38 kd was produced by the clone which reacted with the antibodies raised against the virus. a 20 kd protein which may be derived from the 38 kd protein contained the antigenic epitopes of the protein vp1 of the virus. injection of 10-20 micrograms of the partially purified 38 and 20 kd proteins or a lysate of cells containing 240 micrograms of the prote ...19921378734
genetic relationships between southern african sat-2 isolates of foot-and-mouth-disease virus.sequencing of part of the 1d gene of foot-and-mouth disease virus was used to determine the relationships between sat-2 viruses isolated from outbreaks which occurred in cattle in zimbabwe and namibia and in impala in south africa between 1979 and 1989. the results demonstrated that the outbreaks in different countries were unrelated. surprisingly close relationships were shown between all sat-2 viruses isolated from cattle in zimbabwe since 1983 but the two major epizootics which occurred in 19 ...19921334842
a comparison of type o foot and mouth disease virus field isolates from northern thailand.a survey of type o foot and mouth disease (fmd) virus isolates from northern thailand was undertaken to determine the relationship between field viruses and the vaccine in use, and to gauge the range of antigenic variation among field viruses. isolates were collected from the two most recent epizootics, 1986-1987 and 1989-1990, and assessed using a two-dimensional neutralisation test to determine their relationship to fmd type o1 bangkok 1960 (o bkk/60) reference (vaccine challenge) virus. the c ...19921335305
modification of foot-and-mouth disease virus o1 caseros after serial passages in the presence of antiviral polyclonal sera.foot-and-mouth disease virus (fmdv) shows a remarkable antigenic variability and, like other rna viruses, presents a high rate of mutation. it has been proposed that selection exerted by antibodies of the host could play a major role in the rapid evolution of fmdv. the present work reports the selection of fmdv antibody-resistant (nr) populations after serial passages of a cloned fmdv o1 caseros strain on secondary monolayers of bovine kidney cells in the presence of subneutralizing antiviral po ...19921374806
antiviral effects of a thiol protease inhibitor on foot-and-mouth disease virus.the thiol protease inhibitor e-64 specifically blocks autocatalytic activity of the leader protease of foot-and-mouth disease virus (fmdv) and interferes with cleavage of the structural protein precursor in an in vitro translation assay programmed with virion rna. experiments with fmdv-infected cells and e-64 or a membrane-permeable analog, e-64d, have confirmed these results and demonstrated interference in virus assembly, causing a reduction in virus yield. in addition, there is a lag in the a ...19921331517
a pathogenesis study of foot-and-mouth disease in cattle, using in situ hybridization.eight calves were exposed in an aerosol chamber to nebulized foot-and-mouth disease virus. two control animals were exposed in a similar manner to cell culture media only. animals were euthanized at intervals and various tissues examined by in situ hybridization using a biotinylated rna probe corresponding to a portion of the viral gene coding for the polymerase enzyme. by this technique large amounts of viral nucleic acid were found in coronary band, interdigital cleft and tongue as early as si ...19921330277
factorial experimental design applied to the immunological study of two foot-and-mouth disease virus subtypes. 1. a greece 1969 -- a allier example.a double immunological cross-test, carried out with the index k method, is subjected to a statistical analysis by a factorial experiment. the a greece and a allier viruses, which have been taken as an example of the calculations procedure, seem to be in 2 immunologically different subtypes.1979231923
relationship between virus neutralization and serum protection bioassays for igg and igm antibodies to foot-and-mouth disease virus.the time interval between administering the serum and the virus was found to influence the results of the in vivo mouse protection test for foot-and-mouth disease antibodies. in particular, for both igg and igm antibodies to strain a12 virus, the mouse protection index increased from zero to a maximum at about 6 h and remained high for at least five days. variations in the antiserum concentration, on a log scale, had a proportional effect on the mouse protection index, if between 1 and 3. the co ...1979219135
inactivated-concentrated virus antigen for indirect complement fixation test of foot-and-mouth the culture fluids of bhk-21 cells infected with each of types o, a, and asia 1 of foot-and-mouth disease virus was added acetylethyleneimine to 0.05% (v/v). the mixtures were incubated at 37 degrees c for 24 hours. to them were then added polyethylene glycol 6000 to 10% (w/v), and the mixtures concentrated to one-tenth of the initial volume. the resulting inactivated-concentrated virus antigens showed a complement fixation (cf) titer ranging from 12 to 24. the recovery rate of cf activity wa ...1978216926
secretory antibody responses in cattle infected with foot-and-mouth disease virus.antibody responses in serum, saliva, nasal secretions, or esophageal-pharyngeal fluid of foot-and-mouth disease virus-infected steers were examined by single radial immunodiffusion and mouse-neutralization tests. in steers infected with type o foot-and-mouth disease virus, high serum antibody titers were detected within 10 days after infection. antibody was first detected in saliva at 30 days and gradually increased to a plateau at about 90 days. small amounts of antibody continued to be secrete ...1978209706
in vitro comparison of foot-and-mouth disease virus subtype variants causing disease in vaccinated cattle.foot-and-mouth disease virus isolates of types o, a and sat 2, from diseased animals in herds routinely vaccinated twice a year were compared antigenically with the vaccine strains in the complement-fixation, neutralization and radial immunodiffusion tests. it was found that strains which had readily infected vaccinated cattle had r values against the vaccine strain in the complementfixation and radial immunodiffusion tests of 30 or less, while strains causing primary outbreaks with little sprea ...1978206626
detection of foot-and-mouth disease virus by competitive elisa using a monoclonal antibody specific for the 12s protein subunit from six of the seven serotypes.foot-and-mouth disease (fmd) prevention and control programs are dependent upon rapid, reliable diagnostic procedures. the widely used fmd diagnostic complement fixation (cf) procedures require a specific antiserum for each of the seven fmdv serotypes making the tests both cumbersome and difficult to standardize. an fmd diagnostic, monoclonal antibody based inhibition-elisa procedure was developed. the test uses a single monoclonal antibody (mab) that reacts with all european and south american ...19901702246
nucleotide sequence of the cdna and the derived amino acid sequence for the major antigenic protein of foot and mouth disease virus, type asia 1 63/72.a 0.9 kb cdna for the foot and mouth disease virus (fmdv) type asia 1 63/72, cloned in the plasmid pur222 by dc/dg tailing method, was expressed into a protein which was immunogenic in guinea pigs and cattle. the protein purified to homogeneity was found to be basic and of 38 kda. a sequence of 879 nucleotides of the inserted cdna was obtained. the nucleotide sequence was 65% gc-rich and was homologous to the gene for vpi of fmdv types a5, oik and c3 to the extent of 35-40%. from the nucleotide ...19921317347
a t cell epitope in vp1 of foot-and-mouth disease virus is immunodominant for vaccinated cattle.synthetic peptides representing regions of the vp1 protein of foot-and-mouth disease virus strain 01 kaufbeuren were screened for their ability to stimulate proliferation of pbmc from virus vaccinated cattle. sites were identified at residue 21-40 (peptide fmdv32) and in the region c-terminal to residue 161. cells responding to fmdv32 were mhc class ii-restricted, cd4+ and secreted il-2. thus, this region is defined as a th site. of 19 virus vaccinated friesian cattle, 89% (17/19) responded to p ...19911702816
maturation of functional antibody affinity in animals immunised with synthetic foot-and-mouth disease virus.a good correlation exists between specific neutralising antibody titre and protection against challenge with foot-and-mouth disease virus (fmdv) in infected or virus-vaccinated cattle, but not in the case of animals immunised with synthetic fmdv peptides. therefore, mechanisms other than simple neutralisation are likely to be important in vivo. antibody affinity may influence the protective capacity of sera from immunised animals and experiments were carried out to measure the functional affinit ...19921316628
international bank for foot-and-mouth disease vaccine: stability studies with virus concentrates and vaccines prepared from international bank foot-and-mouth disease (fmd) vaccine has been established at the pirbright laboratory of the afrc institute for animal health. the bank is based on concentrated virus preparations stored in the gaseous phase of liquid nitrogen and is capable of producing up to 0.5 million cattle doses of each of five common strains of the virus (fmdv) for the member nations of the bank. this paper describes the initial and subsequent testing of the virus concentrates and vaccines prepared f ...19902174597
bovine herpesvirus-1 (infectious bovine rhinotracheitis virus)-based viral vector which expresses foot-and-mouth disease epitopes.a recombinant infectious bovine rhinotracheitis virus (ibrv) vector has been constructed to express bovine growth hormone signal sequence plus a foot-and-mouth disease virus [fmdv (o1k)] capsid protein (vp1) epitope as the n-terminal sequence of an ibrv glycoprotein giii fusion protein on the surface of virus infected cells and on the surface of virus particles. sequences encoding the first 38 amino acids of ibrv giii were deleted from the recombinant to avoid redundant glycoprotein signal seque ...19911722936
antibodies elicited by a biosynthetic peptide related to a major immunogenic area of fmdv a12.foot-and-mouth disease virus (fmdv) capsid contains 60 copies each of four structural proteins, virus proteins 1-4. virus protein 1 (vp1) plays an important immunogenic role, being the only vp that is immunogenic as an isolated protein. even peptides representing a partial amino acid (aa) sequence of vp1 can induce protective immunity in experimental hosts. a 32 aa residue, in a tandem repeat configuration (32dimer), of sero/subtype a-12 lp ab vp1 (aa 132-168) was highly immunogenic for its homo ...19901694429
synthetic peptides as potential vaccines against foot-and-mouth disease.advances made in our knowledge of the structure of foot-and-mouth disease virus have enabled us to identify a fragment, consisting of 20 amino acids, of one of the four proteins of the particle, which elicits neutralizing antibodies in experimental animals and in cattle and pigs. the fragment has been synthesised chemically by merrifield's solid phase method and biochemically as part of different fusion proteins. the level of the immune response to the peptide, which depends critically on the wa ...19901697533
foot-and-mouth disease virus in the llama (lama glama): diagnosis, transmission, and susceptibility.foot-and-mouth disease virus (fmdv) was shown to be transmitted from either cattle to llamas, llamas to swine (interspecies), or llamas to llamas (intraspecies). response to fmdv varied greatly in the 6 llamas studied; 3 llamas developed generalized clinical disease with mild pyrexia, 2 after intradermolingual inoculation, and 1 after exposure to a calf infected with fmdv serotype a24. another contact llama developed vesicular lesions on all 4 extremities but no oral lesions. two contact llamas, ...19901965585
identification of a nucleotide deletion in parts of polypeptide 3a in two independent attenuated aphthovirus strains.a set of antisera specific for each viral polypeptide of foot-and-mouth disease virus was used to provide a full comparison of polypeptides of two strains attenuated for cattle with respect to their parental virulent strains. both attenuated strains, belonging to serotypes o1 campos and c3 resende, were obtained through serial passages of the corresponding virulent strains in chicken embryos. although mutations were scattered throughout the genome, both attenuated strains showed an electrophoret ...19902164734
high-affinity antibody induced by immunization with a synthetic peptide is associated with protection of cattle against foot-and-mouth disease.previous work has shown that the synthetic peptide c-c-(200-213)-p-p-s-(141-158)-p-c-g, in which residues 200-213 and 141-158 correspond to immunogenic regions of the vp1 protein of foot-and-mouth disease virus (fmdv), is capable of inducing high levels of neutralizing antibody but only inconsistent protection of cattle against virulent fmdv challenge. the possibility exists that differences in affinity may well underlie the observed variations in biological effectiveness of the anti-peptide ant ...19911847695
evidence for at least four antigenic sites on type o foot-and-mouth disease virus involved in neutralization; identification by single and multiple site monoclonal antibody-resistant mutants.neutralizing monoclonal antibodies raised against type o foot-and-mouth disease virus have been characterized on the basis of their reactivity with a panel of single site monoclonal antibody-resistant mutants which had defined three antigenic sites. five antibodies neutralized all these mutants, but by selecting further single site mutants with one of these antibodies it was possible to define a fourth site involved in virus neutralization. two monoclonal antibodies still neutralized these mutan ...19892471793
foot-and-mouth disease virus strains isolated from persistently infected cell cultures are attenuated for mice and was previously reported that during serial passage of a bhk-derived cell line persistently infected with foot-and-mouth disease virus, (termed c1-bhk-rc1) the virus became increasingly more virulent for bhk-21 cells (de la torre et al 1988). virus strains isolated from different cell passage levels were tested for virulence in mice and cattle. the results showed that in the course of persistence in bhk cells, fmdv became progressively less virulent for mice and cattle.19901964520
infectious foot-and-mouth disease virus derived from a cloned full-length cdna.a full-length cdna plasmid of foot-and-mouth disease virus has been constructed. rna synthesized in vitro by means of a bacteriophage sp6 promoter inserted in front of the cdna led to the production of infectious particles upon transfection of bhk-21 cells. these particles were also found to be highly infectious for primary bovine kidney cells as well as for baby mice. the difficulty in cloning the foot-and-mouth disease virus cytidyl tract in escherichia coli was circumvented by joining two sep ...19902159523
attenuation of mengo virus through genetic engineering of the 5' noncoding poly(c) tract.the murine cardioviruses, such as the mengo and encephalomyocarditis viruses, and the bovine aphthoviruses, such as foot-and-mouth disease virus, are distinguished among positive-strand rna viruses by the presence of long homopolymeric poly(c) tracts within their 5' noncoding sequences. although the specific lengths (60-350 bases) and sequence discontinuities (for example, uridine residues) that sometimes disrupt the homopolymer have served to characterize natural viral isolates, the biological ...19902153940
mouse protection test as a predictor of the protective capacity of synthetic foot-and-mouth disease vaccines.a passive immunity test (mpt) in suckling mice for the quantification of protective anti-foot-and-mouth disease virus (fmdv) antibodies in serum is described. comparisons with titres obtained using conventional serum neutralization tests show that for cattle given synthetic peptide vaccines this in vivo assay is a better indicator of protection, while for convalescent animals and virus-vaccinates both tests are equally valid predictors of immune status. cleavage of fc fragments from anti-virus o ...19911848960
freeze-drying foot-and-mouth disease virus antigens. ii. for use in the and inactivated preparations of foot-and-mouth disease virus strains 01 bfs 1860 and a22 irq 24/64 were freeze-dried in the presence or absence of additive solutions and assessed for their reactivity by elisa at intervals over a six month storage period at various temperatures and also after reconstitution and subsequent storage with or without glycerination. the type specificity of all antigen preparations was maintained throughout the study period and the potency of antigens, judged by ti ...19902175750
inactivation of viral agents in bovine serum by gamma irradiation.cell culture origin or suckling mouse brain origin viruses of akabane disease, aino, bovine ephemeral fever, swine vesicular disease, hog cholera, bluetongue, and minute virus of mice were each suspended in bovine serum. aliquots (1 ml) were exposed to various doses of gamma radiation from a 60co source while at -68 degrees c. aliquots (100-ml) of serum from a steer experimentally infected with foot-and-mouth disease virus were similarly irradiated. the samples were assayed for infectivity in ce ...19902123735
quantification of intact 146s foot-and-mouth disease antigen for vaccine production by a double antibody sandwich elisa using monoclonal antibodies.a double antibody sandwich (das) enzyme-linked immunosorbent assay (elisa) was developed to quantify 146s antigen of foot-and-mouth disease virus (fmdv) strain a10 holland grown in suspension cultures of surviving bovine tongue epithelium. when virus harvests were incubated with trypsin--which affects vp1, the most immunogenic structural protein of fmdv--the concentration of 146s antigen as determined by elisa was reduced by greater than 90%. therefore, the test detected essentially only those v ...19902178351
[virus carriers in foot-and-mouth disease. review].fmdv infection can cause a long lasting virus carrier state in the oesophageal-pharyngeal (op) region of cattle, sheep, goats, african buffalo, wildebeest and kudu. virus can be recovered from op fluids with low titres for several months up to more than 2 years. during this time phases of positive virus recovery are interrupted by negative phases. the number of virus carriers decreases as time progresses. the virus carrier state is always accompanied by fmdv antibodies in serum and op fluid. vac ...19902191649
protection of cattle and swine against foot-and-mouth disease, using biosynthetic peptide vaccines.a single dose of foot-and-mouth disease (fmd) virus protein 1 (vp1) peptide, expressed in escherichia coli as a fusion protein with 190 amino acids (aa) of the le' protein of the tryptophan operon of e coli, elicited an immune response in steers sufficient to withstand the challenge of exposure to animals with acute fmd. the 58-micrograms dose of viral peptide, composed of a segment of the vp1 from the a12 strain (a12) of fmd virus (fmdv; a12-32dimer) in a tandem repeat configuration of aa137 th ...19902154148
variation in foot-and-mouth disease virus isolates in kenya: an examination of field isolates by t1 oligonucleotide fingerprinting.ribonuclease t1 oligonucleotide maps of strains of 4 of the endemic serotypes of foot-and-mouth disease virus isolated in kenya between 1964 and 1982 have been compared with data obtained in complement-fixation and neutralization tests. there was a continual change in the oligonucleotide maps obtained for all the serotypes examined. this genetic heterogeneity was generally associated with antigenic variation. viruses isolated during the 12-month course of an epidemic of the sat 1 serotype showed ...19852413611
use of in situ hybridization for the detection of foot-and-mouth disease virus in cell culture.biotinylated complementary dna (cdna) and rna probes were prepared from a specific and highly conserved section of the foot-and-mouth disease virus (fmdv) genome coding for the rna-dependent rna polymerase. hybridization was conducted on fmdv-infected, bovine enterovirus (bev)-infected, and noninfected swine kidney cell cultures. the detection system utilized the enzyme system streptavidin-alkaline phosphatase, the substrate phosphate, and the chromogen nitroblue tetrazolium. intense cytoplasmic ...19892562224
experimental infection of eland (taurotrages oryx), sable antelope (ozanna grandicomis) and buffalo (syncerus caffer) with foot-and-mouth disease virus.the course of experimental infection of a type sat 1 fmdv strain was studied in buffalo, sable antelope and eland following tongue inoculation and contact and has been compared with that in cattle. all species became infected, although disease was less severe in the game animals and larger amounts of virus were required to infect game animals than cattle. neutralizing antibody titres were high and were maintained for an extended period in buffalo, sable antelope and eland. the carrier state was ...19892584449
[detection of neutralizing antibodies in calves after single vaccination against foot-and-mouth disease virus type asia 1 in the field].on june 20th 1984 appeared the first fmd-type asia 1 outbreak in greece. around the outbreak all susceptible animals were vaccinated with asia 1 vaccine produced by iffa mereiux. three weeks after this first vaccination blood samples have been collected and examined for neutralizing antibodies. from 101 examined calves 37 were younger than 6 months, 63 between 6-11 months and one was 12 months old. the titer of the first group was less than 1.2 in 14 and greater than 1.8 in 8 calves. by the seco ...19911659374
comparison of vaccine strains and the virus causing the 1986 foot-and-mouth disease outbreak in spain: epizootiological analysis.rnas of the most recent foot-and-mouth disease virus isolated in spain (a5sp86) during the 1986 outbreak, and of the three vaccine strains in use at that time in that country, have been compared. although these viruses are serologically indistinguishable, differences have been found among them by t1 fingerprinting. this genetic heterogeneity affects the immunogenic vp1 gene, with amino acid changes located at the carboxyterminal end of the molecule. vp1-coding sequences obtained have been compar ...19902156389
a study of antigenic variants of foot-and-mouth disease virus by polyacrylamide gel electrophoresis of their structural polypeptides.twenty-nine foot-and-mouth disease (fmd) type a virus strains, previously classified serologically as distinct subtypes were analysed by polyacrylamide gel electrophoresis (page) to determine the extent of variation in the pattern of the structural polypeptides and to evaluate the technique as an aid to existing subtyping techniques. the majority of the subtypes examined had distinct polypeptide patterns, however, some variation also occurred between strains within a subtype. the position of vp2 ...19852412337
[outbreak of foot-and-mouth disease in northern benin during the 1990-1991 dry season].an outbreak of foot-and-mouth disease damaged the north-benin during the 1990-1991 dry season (november to may). coming from outside the benin, it spread out very quickly in the country essentially because of trans-humant herds. no measures have been taken to limit this sickness which is endemic and which regularly exhibits outbreaks in benin. antibodies to types a, o and sat2 of the foot-and-mouth disease virus were detected in the sera during this outbreak.19911824131
homologous interference by a foot-and-mouth disease virus strain attenuated for attenuated strain of foot-and-mouth disease virus (fmdv) of the a24 cruzeiro subtype grew less well than wild-type virus in primary bovine fetal kidney (pbk) cells resulting in a 4-log lowered efficiency of plaque formation. both wild-type and attenuated virus grew equally well in baby hamster kidney (bhk) cells and in suckling mice. using pbk cells, virus-specific rna of the wild-type accumulated up to 6 hours after infection. in contrast, pbk cells infected with the attenuated strain made l ...19852415086
infection of cattle by airborne foot-and-mouth disease virus: minimal doses with o1 and sat 2 has been constructed and methods developed for exposing individual cattle to two strains of foot-and-mouth disease (fmd) virus in aerosols to determine the minimal infective dose by the respiratory route. the aerosols used were produced either artificially by a spinning-top aerosol generator, in which case they were of homogeneous small particle size (less than 3 micron in diameter) or else they were derived naturally from infected pigs, in which case the particles were heterogeneous i ...19872832913
isotype responses of infected, virus-vaccinated and peptide-vaccinated cattle to foot-and-mouth disease elisa to measure bovine serum immunoglobulin isotypes (igg1, igg2, igm and iga) specific for foot-and-mouth disease virus (fmdv) or for synthetic fmdv peptides is described. sera from cattle infected by fmdv, vaccinated with conventional inactivated virus vaccines or vaccinated with synthetic peptides were examined using this assay. generally igg subclasses dominated the antibody responses of all groups after an early igm response had waned. an exception to this pattern was seen in the case o ...19902163575
use of inactivated foot-and-mouth disease virus antigen in liquid-phase blocking elisa.a liquid-phase blocking elisa is used by the world reference laboratory for foot-and-mouth disease for the quantification of antibodies to foot-and-mouth disease virus. the potential for using inactivated fmdv antigens in the assay has been assessed by titrating bovine convalescent sera to all seven serotypes and comparing the titres obtained with live or inactivated antigens. the titres were similar indicating that either live or inactivated antigens can be used in the liquid-phase blocking eli ...19902170435
identification of foot-and-mouth disease virus replication in vaccinated cattle by antibodies to non-structural virus proteins.antibodies raised in cattle against foot-and-mouth disease virus by vaccination or by experimental infection were distinguished. vaccination elicited only antibodies to virus capsid proteins and the polymerase 3d. virus replication in cattle elicited additional antibodies directed against the non-structural proteins 2b, 2c, 3ab1, and/or 3c irrespective of prior vaccination or whether the cattle exhibited symptoms of disease. non-permissive mice inoculated with virus responded in the same way, in ...19902163574
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 complex-trapping-blocking (ctb) elisa, using monoclonal antibodies and detecting specifically antibodies directed against foot-and-mouth disease types a, o and c. ii. application.the complex-trapping-blocking (ctb) enzyme-linked immunosorbent assay (elisa) was evaluated to detect antibodies directed against foot-and-mouth disease virus (fmdv) strains a10 holland, o1 bfs, and c1 detmold. log10 serum titres of uninfected, unvaccinated cattle (n = 100) were less than 1.80 in the ctb-elisa. sera from cattle vaccinated with either monovalent or trivalent vaccines were tested in both the ctb-elisa and the serum neutralisation test (snt); titres in both tests correlated positiv ...19902173249
foot-and-mouth disease virus subtyping by sequencing vp1 order to use nucleotide sequencing for foot-and-mouth disease virus (fmdv) diagnostic subtyping, it is necessary to shorten the time required for preparation of suitable templates. the time required for analysis was reduced by use of the viral rna present in the total rna extract of tissue from infected cattle as a template in the sanger sequencing reaction. results are now available within 3 days. the sequences determined encode capsid protein vp1 and therefore major neutralization epitopes. ...19902169671
a complex-trapping-blocking (ctb) elisa, using monoclonal antibodies and detecting specifically antibodies directed against foot-and-mouth disease types a, o and c. i. method and characteristics.a complex-trapping-blocking (ctb) enzyme-linked immunosorbent assay (elisa) was developed for the detection of antibodies directed against foot-and-mouth disease virus (fmdv) strains a10 holland, o1 bfs, and c1 detmold. for each strain two monoclonal antibodies directed against different antigenic sites of fmdv were used. the assay used either infectious, not inactivated antigen or inactivated antigen. we concluded that the ctb-elisa was sensitive, type-specific, and more reproducible (p less th ...19902173248
characterization of anti-idiotypic antibodies generated against foot-and-mouth disease virus neutralizing monoclonal antibodies.a series of seven neutralizing monoclonal antibodies (nmabs) against type a12 foot-and-mouth disease virus (fmdv) was used to induce polyclonal anti-idiotypic antibodies (anti-ids) in rabbits. the anti-ids were semi-purified through isotype affinity columns and assayed by solid-phase radioimmunoassay for cross-reactivity. nmabs which map to the same epitope on the virion appear to contain a common idiotype, and the corresponding anti-ids competitively inhibited the virus-nmab reaction. using a m ...19892550021
[synthetic immunogenic complexes containing a peptide from the surface protein of the foot-and-mouth disease virus].synthetic constructions containing a peptide antigenic determinant (c-terminal peptide 205-213 of the surface vp1 protein of the foot-and-mouth disease virus, o1k strain), glucosaminylmuramayl dipeptide (gmdp), and polyionic synthetic carriers were prepared. the polymerized peptide and peptide-bsa conjugates were synthesized as well. among the constructions obtained only peptide-bsa conjugate proved to be highly immunogenic. application of synthetic constructions to design immunogenic complexes ...19902173604
inactivation of foot and mouth disease virus in skimmed milk with propionic acid, citric acid and hydrogen order to protect farm animals from infections such as foot and mouth disease (fmd) and tuberculosis, the pasteurisation of milk and milk products designated for the feeding of animals is compulsory in switzerland. nowadays, milk products are often treated chemically with acids or with hydrogen peroxide in order to keep bacterial contamination low. the capacity of these chemical treatments to inactivate fmd virus in skimmed milk within 6 h at 5 degrees c was tested in this study. the results i ...19901966751
serological probes for some foot-and-mouth disease virus nonstructural proteins.foot-and-mouth disease virus (fmdv) o1 kaufbeuren-specific cdna fragments were subcloned into the e. coli expression vector prit.2t. fusion proteins thus produced in bacteria were purified by affinity chromatography and inoculated into rabbits. three sera thus obtained were found to be monospecific for fmdv proteins 3a, 3c, and 3d, respectively. two others were prevalently directed against protein 2c, but in addition, either to protein 2b or to protein 3a. five out of six mature nonstructural vi ...19892554586
[an immunoenzyme method of isolation of foot-and-mouth disease virus by using beta-lactamase conjugate with virus-specific antibodies].it was shown that in was feasible to use conjugates of virus-specific antibodies and beta-lactamase from bacillus licheniformis 749/c to identify aphthosa virus antigens. the antigen titers determined by enzyme immunoassay (eia) using a beta-lactamase conjugate were 5-64 times higher than the analogous indices of the complement fixation test. unlike eia, that by using the antibody conjugates with peroxidase or alkaline phosphatase there were observed no "background" responses.19892559667
heterotypic protection induced by synthetic peptides corresponding to three serotypes of foot-and-mouth disease virus.synthetic peptide vaccines of the general sequence cys-cys(200-213)-pro-pro-ser-(141-158)-pro-cys-gly, where the numbered residues refer to vp1 sequences of three different strains of foot-and-mouth disease virus, have been evaluated in cattle and guinea pigs. high levels of serotype-specific (homotypic) antiviral and antipeptide antibody were produced with each peptide. the a- and o-serotype peptides provided complete protection of guinea pigs against their respective virus challenges. the c-se ...19902157884
[immune response against foot-and-mouth disease virus in cattle: effect of vaccination].foot and mouth disease virus (fmdv) is one of the most feared animal virus and vaccination still has to be used in many countries. in previous reports, using a murine model, we studied the cellular basis of immune responses against fmdv and were able to show that they are atypical. in cattle, although complete protection may be attained after only one dose of killed virus vaccine, very little is known about protection against fmdv, except for antibody responses, but practically nothing concernin ...19892562135
a study of antigenic variants of foot and mouth disease virus type a in india between 1977 and 1985.the structural polypeptides of thirty-three field isolates of foot and mouth disease virus (fmdv) collected in india between 1977 and 1985 were analysed by sds-polyacrylamide gel electrophoresis. they were placed in eleven groups based on their patterns and compared with results of conventional serological (virus neutralisation and complement fixation) tests. variation occurred in the structural proteins of the viruses isolated between 1977 and 1981; however, the polypeptide patterns of viruses ...19901966752
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
rapid isolation of monoclonal hybridoma cultures by a 'fusion-cloning' method: the requirement for aminopterin.hybridomas were generated by fusing the balb/c sp2/0 myeloma-like cell line with either: (i) splenocytes from balb/c mice immunized with foot-and-mouth disease virus (fmdv), rinderpest virus (rpv), peste des petits ruminants virus (pprv), african swine fever virus (asfv) or pig thymocytes; or (ii) lymph node cells from cattle immunized with fmdv. if the fusion mixtures were plated in cloning medium of methyl cellulose and hat medium, small hybridoma colonies developed which rarely survived. fusi ...19911954000
modification of foot-and-mouth disease virus after serial passages in the presence of antiviral polyclonal sera.foot-and-mouth disease virus (fmdv) shows a remarkable antigenic variability. like other rna viruses, this virus has a high rate of mutation. it has been proposed that selection exerted by the host's antibodies could play a major role in the rapid evolution of fmdv. the present work reports the selection of fmdv antibody-resistant populations (nr), after serial passages of cloned fmdv a24 cruzeiro strain on secondary monolayers of bovine fetal kidney cells in the presence of subneutralizing anti ...19892548330
evaluation of techniques to demonstrate foot-and-mouth disease virus in bovine tongue epithelium: comparison of the sensitivity of cattle, mice, primary cell cultures, cryopreserved cell cultures and established cell lines.tongue epithelia infected with each of the 7 serotypes of foot-and-mouth disease virus (fmdv) were used to evaluate in vivo and in vitro systems for the detection of fmdv. cattle inoculated by the intradermal route in the tongue (idl) and suckling mice inoculated intraperitoneally were compared for susceptibility to fmdv with freshly prepared bovine thyroid cell cultures; cultures from cryopreserved bovine thyroid, bone marrow, mammary gland, myocardium, tongue, ovary and kidney cells; cultures ...19892549683
detection of foot-and-mouth disease virus with dna probes in bovine esophageal-pharyngeal fluids.infectivity and dot-blot hybridization techniques were compared for the detection of fmdv in esophageal-pharyngeal fluids from experimentally infected cows. the probe used includes the viral polymerase sequence which allows the detection of the three types of virus (a, o, and c) with equivalent sensitivity. virus was detected by dot-blot hybridization as well as by infectivity, according to sample analysis of esophageal-pharyngeal fluids extracted seven days post-infection. it was not possible t ...19882833204
antibodies to foot-and-mouth disease virus infection associated (via) antigen: use of a bioengineered via protein as antigen in an enzyme-linked immunosorbent assay (elisa) to detect antibodies to foot-and-mouth disease (fmd) virus infection associated (via) antigen (viral rna polymerase) in cattle sera, was developed using a bioengineered via (biovia) protein antigen. compared with the classical immunodiffusion test, with viral rna polymerase purified from infected cell cultures as antigen, this elisa was more sensitive. however, depending on the cattle population examined, sera with antibodies to viral rna polymerase, ...19892549685
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
antigenic analysis of serotype o foot-and-mouth disease virus isolates from the middle east, 1981 to 1988.during the period 1981-88 foot-and-mouth disease virus (fmdv) serotype o continued to be isolated from outbreaks in the middle east. field isolates submitted to the world reference laboratory have been examined in relation to reference strains by either complement fixation, virus neutralization or enzyme-linked immunosorbent assays. most isolates were related to the european type o1 reference strains although strains emerging in late 1987 and 1988 were more closely related to o1/manisa. in addit ...19902168609
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
antigenic comparison of the polypeptides of foot-and-mouth disease virus serotypes and other picornaviruses.the cross-reactivity of proteins coded for by the seven serotypes of foot-and-mouth disease virus (fmdv) was assessed by reaction of infected cell lysates with polyclonal and monospecific antisera against the structural and nonstructural proteins of fmdv type a12 strain 119ab. it was shown that the homologous polypeptides from most serotypes are antigenically related. the least cross-reactivity occurred between vp1, vp3, and the protease (3c) of type a12 and south african territories types 1 and ...19872437694
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
rapid selection of genetic and antigenic variants of foot-and-mouth disease virus during persistence in cattle.rapid evolution of foot-and-mouth disease virus (fmdv) is documented during persistent infections of cattle. the carrier state was established experimentally with plaque-purified fmdv of serotype c3. virus was recovered from the esophageal pharyngeal area of the animals up to 539 days postinfection. analysis of capsid proteins by electrofocusing and by electrophoretic mobility of the genomic poly(c)-rich tract suggested heterogeneity in several isolates and sequential dominance of viral subpopul ...19882835508
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
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
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