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C Gale

Publications and source records attributed to C Gale.

12 recordsLinked to original sources

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 affinity for synthetic FMDV peptide of sera from guinea pigs and cattle given various synthetic vaccines. In guinea pigs given a single dose of synthetic vaccine, antibody affinity increased with time after immunisation. In cattle, however, administration of a second dose of peptide 21 days after the first markedly retarded the process of affinity maturation. For guinea pig sera of equivalent neutralising activity, those of higher functional affinity had higher protective indices than those of lower functional affinity. Knowledge of the importance of antibody affinity in protection against FMD is important for an improved understanding of the mechanisms of protection and for the design of novel vaccines.

Adjuvants, Immunologic

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 promoter. The sequences encoding the first 38 and the first 21 amino acids of the IBRV gIII were deleted from the hybrid viruses containing inserts of the monomeric and dimeric FMDV epitope sequences, respectively, to avoid redundant signal sequences. Plaque immunoassay experiments with guinea pig and bovine anti-FMDV peptide antisera, and with anti-IBRV gIII monoclonal antibodies demonstrated that IBRV-FMDV fusion proteins were expressed in virus-infected MDBK cells. Immunoelectron microscopy analyses demonstrated that the IBRV-FMDV fusion proteins were expressed as repeated structures on the surface of virus particles. Experiments showed that the recombinant IBRV-FMDV viruses protected cattle from IBRV (Cooper) challenge and induced anti-FMDV peptide antibodies, thereby demonstrating that the FMDV epitopes were expressed in vivo.

Amino Acid Sequence

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 sequences, but IBRV gIII epitopes detected by anti-gIII monoclonal antibodies were retained. Phenotypes were confirmed by in situ immunostaining of virus plaques with anti-FMDV peptide sera, by immunogold staining of permeabilized- and non-permeabilized infected cells, and by virus neutralization experiments with anti-FMDV peptide sera. Vaccination with the IBRV-FMDV recombinant induced protective levels of anti-FMDV antibodies in calves and protected them from challenge with virulent IBRV.

Amino Acid Sequence

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 or anti-peptide IgG results in a marked decrease in MPT titres although binding to virus in ELISA is unaffected, indicating that intact antibodies are required for in vivo clearance of FMDV. Cross-protection studies demonstrate that anti-peptide sera, while less potent than anti-viral sera in conferring passive immunity against FMDV challenge, have a wider protective range than anti-viral sera within the O serotype and also between O and A serotypes. Possible qualitative differences between anti-viral and anti-peptide sera are discussed in the light of these findings.

Animals

Pneumatometra.

We report a patient who had a significant amount of gas distending the uterine cavity. Severe cervical stenosis was noted at the time that curettage was performed. Because of the cervical stenosis, gas was trapped within the endometrial cavity.

Aged

Isotype responses of infected, virus-vaccinated and peptide-vaccinated cattle to foot-and-mouth disease virus.

An 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 of a group of immature calves given multiple or high doses of synthetic peptide and in which levels of IgM continued to rise until the end of the experimental period. Both infected animals and those vaccinated with inactivated virus mounted antibody responses in which IgG1 titres tended to predominate over those of IgG2. In some infected animals, an early IgG2 response was evident but resolution of lesions and clinical recovery did not occur until IgG1 antibody appeared in the serum some days later. In synthetic-peptide immunized animals the response was more variable but IgG1:IgG2 ratios at 21 days postvaccination were significantly lower than those of virus-vaccinated animals. It is proposed that differences in the isotype profiles induced by conventional FMD vaccines and those resulting from vaccination of cattle with synthetic FMDV peptides may in part account for the lower protective index of peptide-induced antibodies.

Animals

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-serotype peptide appeared to be less effective than the other peptides. In cross-protection studies (heterotypic) in guinea pigs, it was possible to protect A-serotype peptide-vaccinated animals against O-virus challenge and vice versa. Some heterotypic protection was also achieved with the C-serotype peptide. The heterotypic protection observed related more to the presence of cross-reactive antipeptide antibody than to neutralizing antibody.

Amino Acid Sequence

Immunization against foot-and-mouth disease with synthetic peptides representing the C-terminal region of VP1.

Foot-and-mouth disease virus challenge experiments in guinea-pigs and immunoassays with a range of peptides equivalent to either or both of the sequences 141 to 158 and 200 to 213 of VP1 showed the most effective structure, in terms of protection, to be one in which both 'sites' were present with a minimum of additional amino acids. An 80 residue peptide comprising amino acids 134 to 213 was considerably less effective than 40 or 45 residue peptides. The major site for the induction of protection was deduced to be in the region 141 to 158. Thus, protection with the 40 or 45 residue peptide did not appear to be due to the presence of antibody directed solely to the 200 to 213 sequence. Finally, induction of antibody to the latter site appeared to be dependent on both the size of the peptide and the disposition of 'sites' within it.

Animals

Protection of cattle against foot-and-mouth disease by a synthetic peptide.

A chemically synthesized peptide consisting essentially of two separate regions (residues 141 to 158 and 200 to 213) of a virus coat protein (VP1) from the O1 Kaufbeuren strain of foot-and-mouth disease virus was prepared free of any carrier protein. It elicited high levels of neutralizing antibody and protected cattle against intradermolingual challenge by inoculation with infectious virus. Comparative evaluation of this peptide with a single-site peptide (residues 141 to 158) in guinea pigs suggests the importance of the VP1 carboxyl terminal residues in enhancing the protective response.

Animals