a novel structure seen when foot-and-mouth disease virus-induced poly (u) polymerase acts in a cell-free system. 19826290687
serological analysis of recent type o foot-and-mouth disease virus isolates from europe. 19826291221
partial characterization of temperature-sensitive mutants of foot-and-mouth disease virus, o1 caseros strain.the preliminary characterization of four temperature-sensitive (ts) mutants of the o1 caseros strain of foot-and-mouth disease virus is described. two mutants, ts 6 and ts 40, showed a very low rna synthesis rate at nonpermissive temperature and were classified phenotypically as rna(-). shift-up experiments demonstrated an incapacity to organize the rna replicative process at nonpermissive temperature. another mutant (ts 139) behaved phenotypically as rna(+) and its virions were more thermolabil ...19826292127
concentration of foot-and-mouth disease virus in milk of cows infected under simulated field conditions. 19826292275
neutralization of foot-and-mouth disease virus. ii. further parameters related to the sensitization of the 140s virion by antibody.the reaction of foot-and-mouth disease virus (fmdv) with 12s subunit/140s virion cross-reactive (sensitizing) antibody was studied in order to elucidate the requirements for neutralization versus sensitization. the presence of sensitizing antibody in immune serum caused an atypical in vitro neutralization response curve and a non-neutralized fraction. cell-associated (cytophilic) antibody was not present in the system. dissociation of the immune complex was not a factor and sensitized virus adso ...19826292352
the positively charged structural virus protein (vp1) of foot-and-mouth disease virus (type o1) contains a highly basic part which may be involved in early virus-cell interaction.polypeptides of 'trypsin-resistant' (tr) variants of foot-and-mouth disease virus type o1 (bfs 1860) were analysed by electrofocusing and two-dimensional gel electrophoresis. in contrast to parent o1 virus, trypsin treatment of these variants did not reduce their infectivity and their ability to attach to susceptible cells, although vp1 was cleaved as in the parent virus. in otr1, one of the cloned isolates, an additional polypeptide (vpa) with a mol. wt. approx. 31 x 10(3) (31k), was found whic ...19826292355
[immune response in guinea pigs to foot-and-mouth disease virus. study of the biological activities of igg subclasses in hyperimmunized animal sera]. 19806292997
comparative immunogenicity of 146s, 75s and 12s particles of foot-and-mouth disease virus. 19826293410
further characterization of a protein kinase from foot-and-mouth disease virus.acid disruption of foot-and-mouth disease virus released a protein kinase activity that sedimented at less than 7s. this enzyme was separated into three peaks of activity by ion-exchange and hydroxylapatite chromatography. analysis of the various enzyme fractions by polyacrylamide gel electrophoresis and silver staining revealed that one of the fractions lacked the major virion structural proteins, but still contained two or three other polypeptides. this enzyme phosphorylated mainly one protein ...19826294327
a tandem repeat gene in a picornavirus.three closely related genes for the small genome-linked protein (vpg) of picornaviruses have been identified by sequence analysis as a tandem repeat in the genome of foot and mouth disease virus (fmdv), strain o1k. this unusual structure was also found in the genome of strain c1o, belonging to a different fmdv serotype. predicted biochemical properties of the three vpg gene products are in excellent agreement with the data from protein analysis of a heterogeneous vpg population from a third fmdv ...19826294604
nature of the antibody response to the foot-and-mouth disease virus particle, its 12s protein subunit and the isolated immunizing polypeptide vp1.inoculation of inactivated 146s foot-and-mouth disease virus particles into guinea-pigs elicited the formation of neutralizing antibody and the serum had a 10-fold higher titre in radioimmunoassay (ria) with 146s particles than with the 12s virus subunit. in contrast, a single inoculation of the 12s subunit or the isolated polypeptide vp1 elicited the formation of antibody having a much lower titre in ria with the 146s particle than with the 12s subunit and low or undetectable neutralizing activ ...19826296284
air sampling of pigs infected with foot-and-mouth disease virus: comparison of litton and cyclone samplers.the air in looseboxes containing groups of pigs in the acute stage of foot-and-mouth disease was sampled simultaneously with two air-sampling devices: a large volume sampler (litton) and a cyclone sampler. although the cyclone sampler was slightly less efficient at trapping airborne virus it was easier to operate. when pigs were sampled individually within a 610 litre cabinet using the cyclone sampler, the mean recovery of virus over a 24 hour period was log10 8 x 6 tcid50 per animal. this figur ...19826296955
competition for cellular receptor sites among selected aphthoviruses.the competition between different types of aphthoviruses (foot-and-mouth disease virus [fmdv]) for receptor site utilization was determined. the southern african territories (sat) types of fmdv absorbed poorly to bhk-21 cells as measured by a radioactivity binding assay but grew to relatively high titers on these cells. on bk cells, however, all three sat types bound well and competed with each other for receptor sites. in addition, unlabeled fmdv types a12 and o1b were able to completely inhibi ...19826297430
immunogenicity of foot-and-mouth disease virus type o1 replicated in either monolayer or suspended bhk cell system.the efficacy of vaccines formulated from the 10th passage of foot-and-mouth disease virus (fmdv) type o1 in monolayer baby hamster kidney (bhk) cells and the 8th passage in suspension bhk cells was compared in steers. the vaccines were inactivated with ethylenimine, contained an equal amount of antigen and were emulsified in oil-adjuvant. six animals were vaccinated with each vaccine. during the challenge of immunity (91 days post-vaccination, dpv), one out of the six steers from the monolayer v ...19836297845
comparison of the amino acid sequence of the major immunogen from three serotypes of foot and mouth disease virus.cloned cdna molecules from three serotypes of fmdv have been sequenced around the vp1-coding region. the predicted amino acid sequences for vp1 were compared with the published sequences and variable regions identified. the amino acid sequences were also analysed for hydrophilic regions. two of the variable regions, numbered 129-160 and 193-204 overlapped hydrophilic regions, and were therefore identified as potentially immunogenic. these regions overlap regions shown by others to be immunogenic ...19826298715
ultrastructural changes and antigen localization in tissues from foot-and-mouth disease virus-infected guinea-pigs.foot-and-mouth disease virus (fmdv)-induced ultrastructural changes in guinea-pig tongue, heelpad, mammary and liver tissues were examined using scanning and transmission electron microscopy. fmdv infection caused cell rounding and the release of virus in membrane limited vesicles in the animal tissues similar to that seen in other work in cell cultures. microfilaments were present which may be responsible for cell rounding. immunoperoxidase labeling revealed the attachment of the virus-infectio ...19826298989
the detection and inhibition of proteolytic enzyme activity in concentrated preparations of inactivated foot-and-mouth disease virus.proteolytic enzyme activity was detected in a large number of concentrated preparations of inactivated foot-and-mouth disease virus. several lines of evidence indicated that at least some of this activity could be attributed to bhk cells, although low levels of microbial contamination in many of our preparations could not be discounted and would certainly enhance the cellular proteolytic activity. from an experiment with different concentrations of trypsin, it was concluded that the proteolytic ...19836300129
physicochemical transformation of milk components and release of foot-and-mouth disease virus.possible mechanisms for protective roles of milk components on foot-and-mouth disease virus present in the milk of infected cows were examined. light scattering bands collected from ficoll-sucrose gradient fractions of skim-milk contained membrane-limited structures but these were non-infectious for bovine kidney cells. infectivity titres in buttermilk higher than those of the original cream or butter suggested association of virus with milk fat globules. increased infectivity titres in skim-mil ...19836302144
mode of penetration and intracellular localization of incoming parental foot and mouth disease virus (fmdv) in bhk cells.the process of penetration and subsequent early stages of replication of foot and mouth disease virus (fmdv) in bhk21 cell cultures have been studied in order to obtain further data about the infectious cycle of this virus. results suggest that fmdv penetrates bhk21 cells by way of pinocytic vesicles. studies of lysosomal (lf) and supernatant (sf) fractions of homogenized suspension of infected cells were carried out to learn the percentage of possible non-specific absorption of infectious virus ...19836302446
identification of amino acid and nucleotide sequence of the foot-and-mouth disease virus rna polymerase.foot-and-mouth disease virus (fmdv) rna polymerase was purified from the polyethylene glycol (peg)-treated supernatant of infected cell media by a combination of ion-exchange chromatography, membrane molecular filtration, and affinity chromatography. the purified rna polymerase which migrated as a single band of 56,000 molecular weight on a polyacrylamide gel was subjected to automated edman degradation and the sequence of the first 30 amino acid residues established. on the basis of previous ev ...19836305004
multiple homologies of oligonucleotide size exist between nucleic acids of picornaviruses.a semi-quantitative analysis of hybrid formation between restriction enzyme-generated subgenomic fragments of cloned cdna prepared from rna of foot-and-mouth disease virus (fmdv) strain o1k and radiolabelled rna from bovine enterovirus, bovine rhinovirus or mengo virus indicated that the hybrids were of oligonucleotide size. they were located in those parts of the fmdv o1k genome that code for the two capsid proteins vp3 and vp1 and the precursor protein p52 as well as at the 3' end. no hybridiz ...19836306155
an attempt at preparing anti-foot-and-mouth disease virus serum. 19836306318
point mutations in polypeptide vp1 of foot-and-mouth disease virus affect mouse virulence and bhk21 cell pathogenicity.virus produced in the first four days after infection of a bhk21 culture was shown to differ from that produced later in the infection. the early virus caused large plaques in ib-rs-2 cell sheets, had a slow cytopathic effect in bhk21 cultures and showed a high virulence for suckling mice. in contrast, the late virus caused small plaques, was rapid in its cytopathic effect and was of low virulence for mice. comparison between one clone each of the early and late virus showed that no change in im ...19836307221
[differentiation of foot-and-mouth disease viruses by an enzyme-bound immunosorbent micromethod (elisa)].fixed were the optimal conditions for the employment of the elisa method. the latter was successfully applied to differentiate and study the foot-and-mouth disease viruses. it was found that elisa was almost fifty times more sensitive as against the passive hemagglutination test, and almost one-hundred times more sensitive than the complement-fixation test. the results were found to correlate fully in the investigation of f. m. d. viruses of various origin with the use of the diagnostic methods ...19836308884
the improvement and standardization of the simplified process for the production of foot and mouth disease virus from bhk suspension cells.improvements have been made to the methodology for the production of foot and mouth disease (fmd) virus from bhk 21 clone 13 suspension cells by the simplified process. data derived from some 600 individual 8-1 cultures covering all seven types of fmd virus has been analysed. the production of virus was shown to (1) have no direct relationship to cell passage level and (2) to be inversely related to the cell multiplication factor observed during the cell growth cycle immediately prior to infecti ...19836309847
hybridoma cell lines secreting monoclonal antibodies against foot-and-mouth disease virus. 1. cell culturing requirements.the production of hybridoma cell lines secreting antibody against foot-and-mouth disease virus (fmdv) was more difficult than the production of similar cell lines secreting antibody against vesicular stomatitis virus or measles virus. a rapid and efficient protocol for the selection and culturing of 'anti-fmdv' hybridoma cultures was therefore developed and is described. this required the determination of the optimal culture medium (commercially available), source of serum supplement, line of my ...19836309848
hybridoma cell lines secreting monoclonal antibodies against foot-and-mouth disease virus (fmdv). ii. cloning conditions.three methods of cloning hybridoma cells--picking colonies from the masterplate, limit dilution cloning, and cloning in semi-solid medium over macrophage (m phi) feeder layers--were compared. cloning in semi-solid medium was found to be the most efficient and reliable, especially with our relatively slow growing anti-foot-and-mouth disease virus (fmdv) antibody secreting hybridoma cells. the optimum culture dish for this cloning was the 6-well (6w) dish (well diameter 1.5 cm), while the optimum ...19836309849
an investigation into causes of resistance of a cloned line of bhk cells to a strain of foot-and-mouth disease virus.the reduced ability of foot-and-mouth disease virus (fmdv) strain asia 1 iran 1/73 to replicate in the cloned bhk cell line aa7 was not due to lack of virus attachment at the cell surface. instead, the main restriction in the viral growth cycle occurred during synthesis and processing of viral macromolecules, and/or during the earliest stages of their assembly. reduced efficiency of penetration and uncoating of virus attached to the cells may also have contributed to inhibition of virus replicat ...19836310850
multiple genetic variants arise in the course of replication of foot-and-mouth disease virus in cell culture.the genetic heterogeneity generated upon passage of foot-and-mouth disease virus (fmdv) in cell culture has been evaluated by t1-oligonucleotide fingerprinting of genomic rna. plaque-purified fmdv o-s7 and c-s8 were propagated by serial low multiplicity infections of bhk-21 (c-13) or ibrs-2 (c-26) cells. in independent parallel passage of the same virus, different oligonucleotide variations were fixed in the rnas. t1-oligonucleotide fingerprinting of rna from 34 individual viral clones derived f ...19836310859
molecular cloning of cdna from foot-and-mouth disease virus c1-santa pau (c-s8). sequence of protein-vp1-coding segment.cdna segments copied from the rna of foot-and-mouth disease virus (fmdv) c1-santa pau (isolate c-s8) have been cloned in plasmid pbr322. a 998-bp dna fragment, that includes the region coding for capsid protein vp1, the carboxy terminus of vp3, and the amino terminus of precursor protein p52 has been sequenced. comparison of the nucleotide sequence with those from fmdv o1k, a(10)61, a12 and c3 indaial (kurz et al., nucl. acids res. 9 (1981) 1919-1931; kleid et al., science 214 (1981) 1125-1129; ...19836311686
histological and histochemical characterisation of mammary gland tissue of cows infected with foot-and-mouth disease by contact exposure.foot-and-mouth disease virus was observed to replicate in secretory epithelial cells of bovine mammary gland alveoli as a result of systemic infection initiated by exposure to infected animals. viral antigens were demonstrated using fluorescent antibody and immunoperoxidase labelling techniques before the development of signs of clinical disease. in addition, labelled antigens were observed associated with cytoplasmic-like fragments in luminal membrane limited structures. histologically, lesions ...19836312518
[passive hemagglutination reaction in differentiating foot-and-mouth disease viruses].experiments were carried out with the use of the passive hamagglutination reaction in the differentiation of foot-and-mouth disease viruses. the investigations made use of purified sera and specific igg antibodies obtained through column chromatography. conjugates were prepared with the use of bis-diazotized benzidine and glutaraldehyde. in experiments with conjugates prepared with igg and glutaraldehyde standard and reproducible results were obtained. the use of the passive hemagglutination tes ...19836312672
cross antigenicity among enteroviruses as revealed by immunoblot technique.antigenic relationships of various human and two animal picornaviruses were investigated by the immunoblotting ("western blot") technique. the viruses included all coxsackievirus b types (1-6), poliovirus types 1-3, several strains of echovirus 11, emc virus, and fmdv. antisera included human sera and sera from rabbits hyperimmunized with either purified picornaviruses, viral structural polypeptides (vp8), boiled or "sample-boiled" virions. group-specific reactions of various extent were observe ...19836312682
association of foot-and-mouth disease virus induced rna polymerase with host cell organelles.the localization of foot-and-mouth disease viral-induced rna polymerase has been determined in situ and in partially fractionated cell components by using polymerase antisera tagged with either peroxidase or ferritin. electron microscopic examination revealed the polymerase to be heavily concentrated on membranes of the smooth membranous vacuoles (smv) which are newly formed during infection and which were previously shown to be the site where newly synthesized viral rna appeared. polymerase ant ...19836313290
gene fusions using the ompa gene coding for a major outer-membrane protein of escherichia coli has been shown previously that fragments of the escherichia coli major outer membrane protein ompa lacking co2h-terminal parts can be incorporated into this membrane in vivo [bremer et al. (1982) eur. j. biochem. 122, 223-231]. the possibility that these fragments can be used, via gene fusions, as vehicles to transport other proteins to the outer membrane has been investigated. to test whether fragments of a certain size were optimal for this purpose a set of plasmids was prepared encoding 16 ...19836313361
the attachment of the foot-and-mouth disease virus asia i iran 1/73 to bhk suspension cells does not require virus specific cell receptors.experiments are described which show that a member of the picornaviridae (fmd virus asia i iran 1/73) attaches to bhk suspension cells in a manner which precludes a requirement for virus specific receptors on the cell plasma membrane. while it may be possible to demonstrate the apparent saturation of the cell surface with multiple doses of virus, an increase of the concentration of the dosing suspension results in more virus attachment. indeed, it was found that with the amounts of virus which w ...19836314941
innocuity testing of foot-and-mouth disease vaccines. ii. aziridine-inactivated antigen produced in baby hamster kidney cells.methods for the testing of preparations of aziridine-inactivated foot-and-mouth disease virus for the absence of infective particles were studied. the system used for virus production, suspension cultures of baby hamster kidney cells, proved to be the most sensitive detection system for traces of infective virus as long as the 146s antigen concentration was below 1 microgram per 10(6) cells. above this level interference may mask the presence of non-inactivated virus. thus in a 1-1 suspension cu ...19836315737
aerosol exposure of cattle to foot-and-mouth disease virus.slight modifications of a small, plastic covered greenhouse provided a chamber for the exposure of cattle of all ages to aerosols of foot-and-mouth disease virus. particle size distributions of aerosols were 76% less than 3 microns, 17% 3-6 microns, and 7% greater than 6 microns immediately after the devilbis no. 40 nebulizer used was turned off and 90% less than 3 microns, 8% 3-6 microns, and 2% greater than 6 microns 20-30 min later. pharyngeal virus growth curves and viremia patterns correlat ...19836315813
structure of the fmdv translation initiation site and of the structural proteins.a cdna clone of foot and mouth diseases virus (fmdv), strain c1, has been sequenced. the limits of the structural genes were defined by comparison with the available protein data. we identified two potential translation initiation sites for the viral polyprotein separated by 84 nucleotides. we suggest that these two initiation sites could be used to express two proteins differing only at the n-terminal, p16 and p20a. this model is supported by the fact that antiserum against a bacterially synthe ...19836316275
isolation of capsid proteins of foot-and-mouth disease virus by chromatofocusing.a method for the isolation of foot-and-mouth disease virus (fmdv) capsid proteins was developed. the fmdv capsid proteins vp1, vp2, vp3 and vp0 were isolated from sucrose gradient purified virus by chromatofocusing in a ph 7.4-4.0 gradient on polybuffer exchanger pbe 94. under the conditions used the proteins eluted in the sequence vp1, vp2, vp0 (when present) and vp3. capsid protein vp4 did not elute and could not be isolated by this method. protein concentration in the eluate was monitored by ...19836317707
chemical basis of antigenic variation in foot-and-mouth disease of the difficulties in controlling foot and mouth disease by vaccination is the occurrence of the virus as seven distinct serotypes because immunity conferred by vaccination against one serotype leaves the animals susceptible to infection by the other six. moreover, the antigenic variation, even within a serotype, can be so great that immunity against the homologous strain of virus need not necessarily ensure protection against infection by other viruses within that serotype. here we report ...19836318114
a serological and biochemical study of new field isolates of foot-and-mouth disease virus type a in peru, 1975 to 1981.three foot-and-mouth disease virus type a isolates recovered from field outbreaks in the department of san martin, peru, during the period 1975 to 1981 were compared with each other, and the south american vaccine strains a24 and a27, by complement fixation (cf), virus neutralization (vn) and polyacrylamide gel electrophoresis (page). complement fixation and vn tests gave comparable results distinguishing the field isolates from each other and from the vaccine strains. analysis of the structural ...19836318421
[comparative testing of the quality of foot-and-mouth disease vaccines prepared with different virus inactivators].formalin, glycidaldehyde, and the binary ethyleneimine were tested under laboratory conditions as inactivators of the foot-and-mouth disease virus along with the possibility of using them in the process of vaccine production. data is presented on the comparative testing for innocuity and immunogenicity for sheep of f. m. d. vaccines produced with such inactivators. results showed the advantages of the binary ethyleneimine as against formalin and glycidaldehyde as an inactivator of the f. m. d. v ...19836318423
use of short analytical ultracentrifugation runs for the isopycnic determination of foot-and-mouth disease virus concentration and density in autoformed caesium chloride gradients.short analytical ultracentrifugation runs of less than six hours with autoformed cscl density gradients were used for routine fmdv density and concentration analysis. the values obtained after short runs were slightly higher for concentration and lower for density than after classical 22 h runs. these differences between the 6 and the 22 h values were related to virus strain and did not seem to result of the incomplete stabilisation of the cscl gradient, but of the shorter virion/cscl contact pe ...19836318644
correlation of surface and internal ultrastructural changes in cells infected with foot-and-mouth disease virus.the surfaces of primary and continuous line cell cultures displayed the same sequence of morphological changes during the course of infection with foot-and-mouth disease virus. these changes could be classified into four broad stages: i) cells were flattened, closely attached to one another and microvilli appeared, ii) cells rounded, microvilli began to disappear and the cells started to separate from one another by cytoplasmic strands, iii) cells were discrete, rounded structures and iv) cells ...19836321000
the standardization of a 'spot-test' elisa for the rapid screening of sera and hybridoma cell products ii. the determination of binding capacity, binding ratio and coefficient of variation of different elisa plates in sandwich and indirect elisa.the different commercially available enzyme-linked immunosorbent assay (elisa) plates were compared for their binding capacity for purified foot-and-mouth disease virus antigen or igg, their binding ratio (a measure of the efficiency with which positive and negative serum samples may be distinguished), and their coefficients of variation within a plate, between plates and between batches of plates. no one plate could be described as having ideal characteristics, and the choice of elisa plate dep ...19846321511
in vitro morphogenesis of foot-and-mouth disease virus.foot-and-mouth disease virion rna is translated efficiently and completely in a rabbit reticulocyte lysate cell-free system. treatment of cell-free lysates with monospecific serum prepared against the individual viral structural proteins or with monoclonal antibodies prepared against the inactivated virus or against a viral structural protein precipitated all of the structural proteins, suggesting that structural protein complexes were formed in vitro. sucrose gradient analysis of the cell-free ...19846321761
using genetically engineered bacteria for vaccine production.we concluded from this and our earlier work that biosynthetically produced fmdv vp1-specific fusion proteins are effective vaccines. whether this method of vaccine production can be extended to many other immunogenic proteins from other organisms is not known. some problems that could be expected to occur with bacterially produced antigens are that the immunogenic site may not be properly exposed or the peptide sequence(s) within that site may not be able to form into the correct configuration. ...19836322643
biochemical map of polypeptides specified by foot-and-mouth disease virus.pulse-chase labeling of foot-and-mouth disease virus-infected bovine kidney cells revealed stable and unstable viral-specific polypeptides. to identify precursor-product relationships among these polypeptides, antisera against a number of structural and nonstructural viral-specific polypeptides were used. cell-free translations programmed with foot-and-mouth disease virion rna or foot-and-mouth disease virus-infected bovine kidney cell lysates, which were shown to contain almost identical polype ...19846323757
the complete nucleotide sequence of the rna coding for the primary translation product of foot and mouth disease virus.the complete nucleotide sequence of the coding region of foot and mouth disease virus rna (strain a1061) is presented. the sequence extends from the primary initiation site, approximately 1200 nucleotide from the 5' end of the genome, in an open translational reading frame of 6,999 nucleotides to a termination codon 93 nucleotides from the 3' terminal poly (a). available amino acid sequence data correlates with that predicted from the nucleotide sequence. the amino acid sequence around cleavage ...19846324120
formaldehyde inactivation of foot-and-mouth disease virus. conditions for the preparation of safe vaccine.the inactivation of foot-and-mouth disease virus by formaldehyde 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 formalde ...19846326708
multiple proteases in foot-and-mouth disease virus replication.translation of foot-and-mouth disease virus rna in a rabbit reticulocyte lysate for short time intervals resulted in the production of the peptides p20a , p16, and p88 (lab, lb, and p1) (r. r. rueckert , recommendations of the 3rd european study group on molecular biology of picornavirus, urbino , italy, 1983). if further translation was prevented, the structural protein precursor p88 was not cleaved, even after prolonged incubation. this result indicates that the mechanism of the cleavage betwe ...19846328018
guanidine-resistant poliovirus mutants produce modified 37-kilodalton proteins.eighteen spontaneous, guanidine-resistant mutants of poliovirus were obtained by plaque selection. isoelectric focusing demonstrated charge changes in a 37-kilodalton protein, px, among three of the mutants. the precursor of px, ncvp5b , also exhibited charge changes among the three mutants. px of 12 mutants was also examined by peptide mapping with staphylococcus aureus v8 protease. nine of the mutants presented modified maps, and seven of these maps were identical. the demonstration of mutatio ...19846328023
biologically active protease of foot and mouth disease virus is expressed from cloned viral cdna in escherichia coli.foot and mouth disease virus o1k cdna had been cloned in escherichia coli. here we report on in vitro recombination of cdna fragments according to the cdna restriction map and on expression of viral proteins in e. coli. use was made of the expression vector pplvp1 , which is known to express the virus capsid protein vp1. recombined cdnas of various sizes were inserted downstream from the vp1 gene. the constructed plasmids differ from each other in the number of virus genes coding for nonstructur ...19846328511
selection of particles and proteins for use as human cytomegalovirus subunit vaccines.uncertainties about the ultimate biologic consequences of using live virus vaccines to confer immunologic protection against cmv have focused attention on the use of noninfectious subunit vaccines. at least two classes of such preparations have been demonstrated to be effective in other systems. the first is virus particles bearing the relevant antigens but lacking nucleic acid (eg, hepatitis vaccine [31]). and the second class is biologically or chemically synthesized proteins or peptides with ...19846329369
studies on the stability of foot-and-mouth disease virus using absorbance - temperature profiles.the main immunogenic component of fmd virus harvests is the intact 140s virus particle. for the production of stable vaccines it is important to ensure that virus strains having a stable capsid should be used. the method of measuring the heat stability of fmd virus by following the increase in optical density of purified virus during capsid breakdown as the temperature is increased was described in 1964 (p. bachrach, 1964, j. mol. biol 8. 348). we have investigated this technique in the hope tha ...19836329854
the thermal death time curve for foot-and-mouth disease virus contained in primarily infected milk.whole and skim milk obtained from cows after intramammary and intravenous inoculation with foot-and-mouth disease virus (primarily infected milk) were exposed to various temperatures ranging from 80 to 148 degrees c for various times ranging from 2.5 s to 27 min then tested for viral infectivity. the average pretreatment titre of the 53 lots of milk used was 10(5.9) plaque-forming units of virus per millilitre 10(3.7)-10(6.8)). a thermal death time curve was plotted using the data obtained. the ...19846330120
effect of lysosomotropic agents on the foot-and-mouth disease virus replication.the effect of two lysosomotropic agents, nh4cl and chloroquine, on the foot-and-mouth disease virus (fmdv) replicative cycle was studied. when the drugs were present throughout the viral replicative cycle, an important inhibition of viral rna synthesis and virus production was detected. the inhibition of viral rna synthesis was maximal when the drugs were present from 30 min before virus infection up to 30 min after that. otherwise, if the agents were added once the viral synthesis has started ( ...19846330983
histone h3 modification in bhk cells infected with foot-and-mouth disease virus.infection of bhk cells with foot-and-mouth disease virus (fmdv) causes a thorough change in the electrophoretic profile of whole nuclear histones. it consists in the disappearance of histone h3 and the appearance of a new polypeptide (pi) which migrates between histones h2a and h4 on sds-polyacrylamide gels. protein pi is detected at 2 hr postinfection (pi), the time in which viral rna synthesis begins to increase, and reaches equimolecular amounts with the remaining core histones 1 hr later, wh ...19846330987
relationship of human rhinovirus strain 2 and poliovirus as indicated by comparison of the polymerase gene regions.cdna clones representing the 3'-terminal region of the human rhinovirus strain 2 genome have been obtained. the sequence of 1425 nucleotides adjacent to the poly(a) tract is presented and contains an open reading frame of 1383 nucleotides. the derived amino acid sequence corresponding to the putative rna polymerase-coding region is compared to those of poliovirus type 1 (mahoney) and foot-and-mouth disease virus a12. a high degree of homology between human rhinovirus strain 2 and poliovirus type ...19846330989
contribution of the "stefan s. nicolau" institute of virology to the electron microscopic study of viruses.the review reflects the concerns of researchers of the "stefan s. nicolau" institute of virology who used electron microscopy techniques with a view to visualizing morphological features of virus structure (influenza, adeno, hepatitis, herpes, cytomegalic, aujeszky, rabies viruses, etc.) and different aspects of the virus - host cell relationships (sendai virus/hep2 cells, influenza and adenovirus/mouse lung, subacute sclerosing panencephalitis/human brain or cell cultures, coxsackie and foot-an ...19846393566
genetically engineered viral vaccines--prospects for the future.genetic engineering (recombinant dna technology)--the revolution in molecular biology--has enabled us to isolate any genes from any source in a pure form, and to move them from one cell to another. it has become possible to program bacterial or yeast cells with foreign genes and force the new host to produce commercially valuable proteins (e.g. hormones, enzymes, diagnostic reagents). it is now also possible to produce viral and bacterial antigens in various types of cells. we hope that this wil ...19826763495
protective role of foot-and-mouth disease virus antibody in vitro and in vivo in guinea-pigs. 19836834003
herpes type 2 infection with unusual generalised manifestations and delayed diagnosis in an adult male.a case of severe generalised herpes simplex type 2 infection is described in an adult male who had known exposure to herpes. the patient first complained of headache, fever and neurological symptoms, and three to six days later of conjunctivitis, severe pharyngitis, arthralgia and vesicular lesions about the body. during the first 14 days of illness, including three in hospital, the patient was diagnosed as having infection with varicella virus, vesicular stomatitis virus, or hand-foot-and-mouth ...19836875292
symposium: international challenges and perspectives: internationalism and survival of foot-and-mouth disease virus in cattle and food products.foot-and-mouth disease is a serious world-wide economic disease of livestock and diverse animal species. the closing of borders to infected countries is a frequent aftermath of disease outbreaks. historically, animals and animal products have been implicated as vehicles for transmission of the disease. control programs encompass stringent importation policies, vaccination, quarantine, and slaughter. joint efforts have been instituted successfully in previous control campaigns and would be the lo ...19807400424
[cloning fragments of the rna polymerase gene of an attenuated variant of the foot-and-mouth disease virus a22].the cdna fragments complementary to rna-polymerase gene and 3'-untranslated genome region of attenuated foot-and-mouth disease virus strain a(22)645 have been synthesized and cloned into a plasmid vector puc19 in e. coli jm109. the cloned cdna fragments were characterized as to their size, orientation towards the plasmid, and localization in the virus genome. restriction maps for complete gene and two cdna clones were constructed.19957477032
picornavirus internal ribosome entry segments: comparison of translation efficiency and the requirements for optimal internal initiation of translation in vitro.on the basis of primary sequence comparisons and secondary structure predictions, picornavirus internal ribosome entry segments (ireses) have been divided into three groups (entero- and rhinoviruses; cardio- and and aphthoviruses; and hepatitis a virus). here, we describe a detailed comparison of the ability of ireses from each group to direct internal initiation of translation in vitro using a single dicistronic mrna (the only variable being the ires inserted into the dicistronic region). we st ...19957478993
identification of critical amino acids within the foot-and-mouth disease virus leader protein, a cysteine protease.the leader protein of foot-and-mouth disease virus (fmdv) is the first component of the virus polyprotein. it is synthesized in two forms, lab and lb, both of which display the ability to cleave the l/p1 junction in trans and to induce the cleavage of the cap-binding complex component eif-4g (p220). the l protease has weak homology to the family of cysteine proteases, which have a catalytic dyad composed of a cysteine and a histidine. mutations have been introduced into fmdv cdna to modify each ...19957483257
foot and mouth disease virus replication in bovine skin langerhans cells under in vitro conditions detected by rt-pcr.the replication of foot and mouth disease virus (fmdv) was studied in isolated bovine skin langerhans cells (lc), in keratinocytes from epidermal cell suspension, and in migrating lc obtained from cultured bovine epidermal sheets in vitro. viral rna replication in infected cells was determined by the reverse transcriptase-polymerase chain reaction (rt-pcr) of the negative fmdv rna strand and by the plaque forming assay of fmdv. it was established that bovine skin lc, keratinocytes, and migratory ...19957483289
immune response of calves to foot-and-mouth disease virus vaccine emulsified with oil adjuvant. strategies of vaccination.calves born to vaccinated cows under the regular annual vaccination programme were vaccinated at different ages using commercial quadrivalent (01, a79, a87 and c85 fmdv strains) vaccine emulsified in oil adjuvant. the antibody responses of vaccinated calves were evaluated using liquid-phase blocking sandwich elisa. all calves 20, 30 and 40 days old having high maternal antibody titres responded well to vaccination. moreover, 25-57% of vaccinated calves showed protective antibody titres both at 9 ...19957483763
isotype profiles induced in balb/c mice during foot and mouth disease (fmd) virus infection or immunization with different fmd vaccine formulations.the igg isotype response in balb/c mice infected with fmdv or immunized with different vaccine formulations using inactivated virus particles as antigen was analyzed at various times post-inoculation. for this purpose an elisa based on polyclonal antibodies for detection and quantification of mouse igg isotypes with fmd virus (fmdv) specificity was developed. three immunomodulators, which have been shown to be very effective in inducing strong and long-lasting antibody responses (bahnemann, arch ...19957483770
antigenic variants in a plaque-isolate of foot-and-mouth disease virus: implications for vaccine production.the occurrence of many subtypes within a serotype of foot-and-mouth disease virus (fmdv) makes it difficult to control the disease by vaccination. although inactivated vaccines are used successfully in many countries, the appearance in the field of antigenic variants against which the vaccines do not confer protection is a constant problem in vaccine manufacture. we had found previously a mixture of antigenic variants in a field isolate of serotype a12. in this report we demonstrate the presence ...19957483796
in vitro synthesis of foot-and-mouth disease virus specific antibodies by porcine leukocytes.we have characterized the in vitro secondary antibody response to fmdv of peripheral blood mononuclear cells (pbmc) from immunized pigs. the results obtained indicated that primed swine leukocytes can support an in vitro t-b cell cooperation which is functional and leads to the production of viral specific antibodies. the response was shown to be independent of viral replication, being induced by both infective and inactivated virus as well as by recombinant polypeptides vp1 and vp3. in all case ...19957487496
pathogenesis of foot-and-mouth disease in swine, studied by in-situ hybridization.eight 7-month-old pigs were inoculated intradermally with 10(3) plaque-forming units of foot-and-mouth disease virus, type o, and killed 24, 48, 72, or 96 h later. numerous tissues from each animal were collected and examined histopathologically and by in-situ hybridization to determine the presence of virus and its correlation with lesion development. the probe for in-situ hybridization was a biotinylated 500-base negative-sense transcription product corresponding to a portion of the gene encod ...19957490337
identification of the active-site residues of the 3c proteinase of foot-and-mouth disease identify the active-site residues of the 3c proteinase of foot-and-mouth disease virus (fmdv), we introduced mutations into the 3c coding region and examined the activity of mutant enzymes on various substrates. based on alignment of fmdv 3c with other picornavirus 3c proteinases and with the trypsin family of serine proteinases, mutations were introduced at residues presumed to be part of the catalytic triad, involved in substrate binding, or present in nonconserved regions. wild-type and mu ...19957491782
quantification of whole virus particles (146s) of foot-and-mouth disease virus in the presence of virus subunits (12s), using monoclonal antibodies in a sandwich elisa.this paper describes a method for the specific quantification of whole virions of foot-and-mouth disease (146s) in the presence of virus subunits (12s). the method involves the use of virus neutralising monoclonal antibodies directed against a linear epitope of the vp1 loop region of a type o virus. the monoclonal antibodies were used as both capture and detecting reagents (labelled with horse radish peroxidase) in a sandwich elisa. such monoclonal antibodies also have the advantage that they do ...19957491813
inducible expression of the p, v, and np genes of the paramyxovirus simian virus 5 in cell lines and an examination of np-p and np-v interactions.the p, v, and np genes of the paramyxovirus simian virus 5 (sv5) were cloned such that their expression was regulated by the tetracycline-controlled transactivator (m. gossen and h. bujard, proc. natl. acad. sci. usa 89:5547-5551, 1992), and mammalian cell lines that inducibly expressed individually the p, v, or np protein or coexpressed the p plus np or v plus np proteins were isolated. a plasmid that expresses the tetracycline-controlled transactivator linked, via the foot-and-mouth disease vi ...19957494313
protective effect of lidocaine in the experimental foot-and-mouth disease pancreatitis.experimental infection of mice with foot-and-mouth disease virus (fmdv) induces a necrotizing pancreatitis of the exocrinar portion of the organ. the lesions are characterized by vascular congestion, edema and interstitial polymorphonuclear leukocyte (pmn) infiltrates. when infected mice were treated with different amounts of lidocaine (a local anesthetic, chemically defined as a tertiary amide compound), reduction in intensity of the pancreatic necrosis and in the number of pmn were observed. e ...19957498445
molecular epidemiology of foot-and-mouth disease (fmd) in israel in 1994 and in other middle-eastern countries in the years 1992-1994.the reverse transcriptase-polymerase chain reaction (rt-pcr) and direct sequencing were employed in the diagnosis and typing of foot-and-mouth disease virus (fmdv) in samples taken during the 1994 disease outbreak in israel. using pcr, virus isolation and serological methods it was shown that the 1994 disease outbreak in israel and other middle-eastern countries was caused by o1 type virus. direct pcr sequencing of vp1 genes and homology analysis of the virus isolates revealed that there were tw ...19957503679
expression of the vp3-vp1 sequence of foot-and-mouth disease virus in escherichia coli.1. cdna recombinants containing the vp3 and vp1 sequences of foot-and-mouth disease virus were isolated and the vp3-vp1 sequence was reconstructed. 2. the reconstructed vp3-vp1 sequence was subcloned into expression vector pex31b and a fusion protein of about 62,000 da was expressed. 3. when injected into mice, the fusion protein was able to elicit the production of antibodies that recognized viral vp1 and vp3. 4. antibodies present in sera from mice immunized with vp3-vp1 protein did not neutra ...19937504968
characterization of foot-and-mouth disease virus by monoclonal antibodies.monoclonal antibodies (mabs) were produced against foot-and-mouth disease (fmd) virus types o1 campos br1/58, a24 cruzeiro br1/55, and c3 indaial br1/71, which are the strains used for production of fmd vaccines in the majority of south american countries. within the library of mabs produced, a group was selected on the basis of their neutralizing titer in cell culture, protective titer in suckling mice, sensitivity to trypsin, and specificity for virus structural proteins. the mabs were utilize ...19937507329
immunogenicity of foot-and-mouth disease virus grown in bhk-21 suspension cells. correlation with cell ploidy alterations and abnormal expression of the alpha 5 beta 1 integrin.bhk-21 suspension cells were characterized with regard to genetic and phenotypic features which might adversely affect the immunogenic properties of foot-and-mouth disease virus (fmdv) grown therein. a positive correlation was found between number of passages in suspension culture and both prevalence of polyploid cells and reduced cell growth on surfaces. suspension cells also revealed differences in the expression of rgd-specific integrins and, in particular, of alpha 5 beta 1, which was shown ...19947511862
unprocessed foot-and-mouth disease virus capsid precursor displays discontinuous epitopes involved in viral neutralization.a foot-and-mouth disease virus (fmdv) cdna cassette containing sequences encoding the capsid precursor p1, peptide 2a and a truncated 2b (abbreviated p1-2a) of type c fmdv, has been modified to generate the authentic amino terminus and the myristoylation signal. this construct has been used to produce a recombinant baculovirus (acmm53) which, upon infection of spodoptera frugiperda insect cells, expressed a recombinant p1-2a precursor with a high yield. this polyprotein reacted with neutralizing ...19947515974
vaccines prepared from chimeras of foot-and-mouth disease virus (fmdv) induce neutralizing antibodies and protective immunity to multiple serotypes of fmdv.the g-h loop of vp1 (residues 132 to 159) of foot-and-mouth disease virus (fmdv) is a prominent feature on the virion surface and has an important role in vaccine efficacy, generation of antigenic variants, and cell binding. using an infectious cdna of fmdv, we have constructed serotype a viruses in which the g-h loop has been substituted with the homologous sequences from serotype o or c. these chimeric viruses replicated to high titer and displayed plaque morphologies similar to those of wild- ...19947523697
antigenic specificity of porcine t cell response against foot-and-mouth disease virus structural proteins: identification of t helper epitopes in vp1.the contribution of each of the viral capsid proteins of foot-and-mouth disease virus (fmdv) in the t cell response of vaccinated pigs has been studied. viral polypeptides, vp1 to vp4, were expressed as fusion proteins in escherichia coli, and were used to stimulate peripheral blood mononuclear cells of vaccinated animals. significant, dose-dependent responses to whole virion were detected in the seven animals analyzed and, in five of them, responses to recombinant polypeptides vp1, vp2, and vp3 ...19947526534
antibodies to the vitronectin receptor (integrin alpha v beta 3) inhibit binding and infection of foot-and-mouth disease virus to cultured cells.the amino acid sequence arg-gly-asp (rgd) is highly conserved on the vp1 proteins of different serotypes and subtypes of foot-and-mouth disease virus (fmdv) and is essential for cell attachment. this sequence is also found in certain extracellular matrix proteins that bind to a family of cell surface receptors called integrins. within the picornaviridae family, enterovirus coxsackievirus a9 also has an rgd motif on its vp1 capsid protein and has recently been shown to utilize the vitronectin rec ...19957533862
the influence of mhc polymorphism on the selection of t-cell determinants of fmdv in cattle.there is a quest for the development of a new generation of vaccines consisting of well-defined subunit antigens. for a number of practical reasons it is attractive to develop vaccines on the basis of synthetic peptides. however, their efficacy may be limited by genetic restrictions imposed on t-cell recognition via major histocompatibility complex (mhc) polymorphism, as shown by many studies using inbred animal species. to study the effect of mhc polymorphism in an outbred species, we selected ...19957534267
structure of the major antigenic loop of foot-and-mouth disease virus complexed with a neutralizing antibody: direct involvement of the arg-gly-asp motif in the interaction.the crystal structure of a synthetic peptide representing the major antigenic loop of foot-and-mouth disease virus (fmdv), complexed with the fab fragment of a neutralizing monoclonal antibody raised against the virus, has been determined at 2.8 a resolution. the peptide shows a high degree of internal structure with a nearly cyclic conformation. the conserved arg-gly-asp motif, involved in the viral attachment of aphtoviruses to cells, participates directly in the interaction with several compl ...19957537661
response of foot-and-mouth disease virus c3 resende to immunological pressure exerted in vitro by antiviral polyclonal sera.the foot-and-mouth disease virus (fmdv) shows a remarkable antigenic variability. like other rna viruses, fmdv has a high mutation rate and it has been proposed that selection exerted by antibodies of the host could play a major role in its evolution. in this work, antiserum-resistant variants of fmdv (nr variants) were selected upon 25 serial passages of a cloned c3 resende strain on secondary monolayers of fetal bovine kidney (fbk-2) cells in the presence of subneutralizing levels of antiviral ...19957542827
antigenic analysis of sat 2 serotype foot-and-mouth disease virus isolates from zimbabwe using monoclonal antibodies.this paper compares strains of foot-and-mouth disease (fmd) serotype sat (south african territories) 2 viruses isolated from zimbabwe and other african countries using monoclonal antibodies (mab). a sandwich-elisa was used to examine the relative binding of anti-sat 2 mab to the various viruses. the mab-binding profiles of viruses isolated from field samples were compared using hierarchical cluster analysis. viruses were obtained from game animals, mainly african buffalo (syncerus caffer) which ...19957543860
[susceptibility of picornaviruses++ to an antiviral of plant origin (meliacin)].meliacine, a peptide associated with antiviral activity isolated from the high plant melia azedarach l (ma) inhibits the replication of different strains of foot and mouth disease virus (fmdv) and poliovirus in bhk-21 or vero cells, respectively, infected at a multiplicity of infection (m.o.i.) of 1. a leaf extract of ma, containing meliacine was added to the culture medium after virus adsorption and maintained up to virus harvest (18 hs). fmdv o1 campos and o69 strains showed 60% and 52% inhibi ...19957568867
a 10-amino-acid linear sequence of vp1 of foot and mouth disease virus containing b- and t-cell epitopes induces protection in mice.the area of foot and mouth disease virus (fmdv) comprising residues 140 and 160 of capsid protein vp1 has been used extensively as an immunogen in natural and experimental hosts. a detailed epitope mapping of this region, however, has not been reported. for this purpose a synthetic peptide containing the residues 135 to 160 (p135-160) of vp1 of fmdv o1 campos was analyzed for its t- and b-cell epitopes. the p135-160 is highly immunogenic, either by itself or coupled to a carrier protein (bsa), e ...19957571431
inactivation of viruses in liquid manure.the stability of some viruses and methods of virus inactivation in liquid manure are reviewed. the authors discuss experimental data on the stability of foot and mouth disease virus, classical swine fever virus, aujeszky's disease virus, african swine fever virus, swine influenza virus, porcine paramyxovirus, bovine virus diarrhoea virus and transmissible gastroenteritis of pigs virus. recommendations and practical advice are given for the choice and application of chemical disinfectants for slu ...19957579641
use of disinfectants in zoos and game parks.disinfection is used in the animal quarters of zoos and game parks as an adjunct to physical cleaning and the removal of potentially contaminated materials. disinfection is particularly useful in reducing infection risks in young animal nursery facilities, and in routine cleaning operations of animal quarters and feeding utensils. specific disinfectants may be selected for certain known microbial contaminants following an infectious disease outbreak. for example, premises contaminated by foot an ...19957579642
m7gpppg cap dependence for efficient translation of drosophila 70-kda heat-shock-protein (hsp70) investigate whether preferential translation of the heat-shock mrnas occurs via cap-independent translation, the requirement for the m7gpppg cap structure for efficient translation of 70-kda heat-shock-protein (hsp70) mrna was quantified by in vitro translation and by in vivo translation following electroporation. hsp70 mrna was transcribed in vitro with and without a cap structure. translation in the rabbit reticulocyte or wheat germ lysate was reduced about 70% when the cap was absent. for ...19957588716
a recombinant foot-and-mouth disease virus antigen inhibits dna replication and triggers the sos response in escherichia coli.the 3d gene of foot-and-mouth disease virus encodes the viral rna dependent rna polymerase, also called virus infection associated (via) antigen, which is the most important serological marker of virus infection. this 3d gene from a serotype c1 virus has been cloned and overexpressed in escherichia coli under the control of the strong lambda lytic promoters. the resulting 51 kda recombinant protein has been shown to be immunoreactive with sera from infected animals. after induction of gene expre ...19957607396
identification of the active-site residues of the l proteinase of foot-and-mouth disease virus.the foot-and-mouth disease virus (fmdv) leader (l) protein is involved in autocatalytic cleavage at the l/p1 junction and in the cleavage of translation initiation factor p220, a subunit of the cap-binding protein complex. it has been suggested that this proteinase has homology to the papain-like family of cysteine proteinases, and from this information, we have investigated the active-site residues by introducing specific mutations into the l gene. mutations of cys-23 to ala or his-120 to leu r ...19957609064
[the use of a carboxymethylcellulose coating for titrating the foot-and-mouth disease virus by the plate-culture method]. 19957620781
bovine t cells preferentially recognize non-viral spacer epitopes in a putative fmdv vaccinal a group of immunized cattle with a variety of mhc class ii types, t-cell responses were detected to a synthetic peptide (fmdv15) proposed as a basis for a vaccine against foot-and-mouth disease. this peptide combines the loop region of vp1 with the c-terminal sequence connected by a spacer (pps). two major immunodominant regions of fmdv15 for bovine t cells were detected, one within the loop region and the other around the spacer. a substantial proportion of the t-cell response to fmdv15 was ...19957625121
the foot-and-mouth disease virus leader proteinase gene is not required for viral replication.the foot-and-mouth disease virus (fmdv) leader (l) proteinase has only two known functions: (i) autocatalytic removal from the n terminus of the viral polyprotein and (ii) cleavage of the p220 subunit of the eukaryotic initiation factor 4f complex, which helps to shut off host protein synthesis. cleavage of p220 appears to be important for picornavirus replication, since rhinoviruses and enteroviruses utilize a different proteinase (2a) to cleave p220. to explore the role of l in fmdv replicatio ...19957636982
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