Use of Unweaned White Mice in Foot-and-Mouth Disease Research

Major immunogenic sites of foot-and-mouth disease virus (FMDV) have been mapped to the C-terminal third of capsid protein VP1; we studied the immunogenicity of a series of TrpE-FMDV fusion proteins containing this region of FMDV strain O1 Campos. Fusion protein TrpE-dCN, which contains a dimer of VP1 amino acid sequences consisting of amino acids 200 to 213 linked by a diproline spacer to amino acids 141 to 158 (200-213 ~P-P-G ~ 141-158), induced the best response. A single inoculation of guinea-pigs with 100 ~tg TrpE-dCN elicited high levels of neutralizing antibodies and protected all the animals against challenge infection with homologous virus. Although the closely related FMDV strains O1 Campos and O1 Caseros induced high levels of cross-protection, TrpEdCN-vaccinated guinea-pigs were poorly protected against challenge infection with heterologous FMDV strain O1 Caseros. Nucleotide sequence analysis revealed that amino acid differences at residues 149 and 152 were critical for the induction of crossprotection and that neutralizing epitopes not present in TrpE-dCN are likely to be responsible for conferring a high level of cross-protection between FMDV strains O1 Campos and O1 Caseros.

mentioning

confidence: 99%

Protection conferred by TrpE fusion proteins containing portions of the C-terminal region of capsid protein VP1 of foot-and-mouth disease virus

Giavedoni

Kaplan

et al. 1991

“…The antibodies were characterized in the indirect and the indirect sandwich ELISA (Ouldridge et al, 1982) and in neutralization tests (Booth et al, 1978;Skinner, 1953) and by immune electron microscopy. The antibodies in this study were all classified as reactive with the trypsin-sensitive site on the basis of their strong reaction in the indirect sandwich ELISA performed as described above with the purified intact 140S particle and failure to react with purified trypsin-treated 140S particles (Fig.…”

mentioning

confidence: 99%

Demonstration of Neutralizing and Non-neutralizing Epitopes on the Trypsin-sensitive Site of Foot-and-Mouth Disease Virus

Ouldridge

Barnett

Parry

et al. 1984

SUMMARYThe isolation of monoclonal antibodies directed against the trypsin-sensitive site on the 140S particle of foot-and-mouth disease virus (FMDV) has enabled the demonstration of at least three distinct epitopes within this site. Reaction with two of these resulted in neutralization of virus infectivity. None of the epitopes appeared to be present on the 12S particles, and one of the neutralizing epitopes was sensitive to even milder configurational changes of the particle.The ability to stimulate neutralizing, i.e. protective, antibody is largely associated with the nucleocapsid (140S particle) of foot-and-mouth disease virus (FMDV). This property is significantly reduced following treatment of the virus with trypsin (Wild & Brown, 1967). The primary immunogenic determinant on the 140S particle appears to be located on the virion polypeptide (VP1) which is the only polypeptide cleaved by trypsin in situ (Wild et al., 1969) and confined to one or two small tracts containing no more than about 20 amino acid residues (Bachrach et al., 1982;Bittle et al., 1982; Strohmaier et al., 1982). However, information on the nature of the antigenic structures formed by these peptides on their own and perhaps in association with other structures is lacking. For example, although VP1 remains intact in the 12S virion subunit, this particle is far less efficient at provoking neutralizing antibody than the 140S particle (Brown & Newman, 1963 ;Cartwright et al., 1982). We have therefore analysed the antigenic structure of the trypsin-sensitive site of FMDV using monoclonal antibodies as a probe.Monoclonal and hybridoma cell lines secreting antibody of the IgG immunoglobulin class to virus strain O1BFS 1860 were isolated from both mouse (using P3-NS1/Ag4-1 myeloma cells and BALB/c mice) and rat (using the Y3 Ag 1.2.3 myeloma line described by Galfre et al., 1979 and Lou F strain rats) fusions. For the preparation of hybridoma cell lines, sucrose-purified 140S antigen either inactivated with acetylethyleneimine or not inactivated was emulsified in Freund's incomplete adjuvant and inoculated intraperitoneally at 28-day intervals. The second or third injection was given without adjuvant, intravenously 3 to 4 days before the spleens were collected. The techniques for the fusion of myeloma cells with spleen cells and the subsequent isolation and cultivation of antibody-secreting cell lines were essentially those described by McMaster & Williams (1979). Both the indirect sandwich enzyme-linked immunosorbent assay (ELISA) (Ouldridge et al., 1982) and neutralization tests (Booth et al., 1978) were used to detect anti-FMDV-secreting cell lines. Briefly, for the indirect sandwich ELISA, rabbit anti-FMDV IgG was absorbed to flexible PVC microtitre plates; this capture antibody was then used to trap purified 140S antigen. Tissue culture supernatants were then reacted with this antigen and the reaction detected with anti-mouse or-rat IgG antibody linked to horseradish peroxidase. For the detection of neutralizing antibody, serial twofold dil...

“…The most significant result was the finding that antiserum to the peptide with the A~2 119C-specific substitution of LoS, although of low titre, neutralized O1 BFS, O1 Kaufbeuren and A~ 2 119C equally. This was corroborated by titrating the serum in the more sensitive mouse index test (Skinner, 1953), in which the infectivity titres ofOt BFS and A~ 2 119C were reduced by 3.5 and 3.9 loglo respectively compared to 5.2 and <0-2 log~0 for the native anti-peptide antiserum.…”

Section: Effect Of Amino Acid 148 On the Specificity Of Peptide Antiseramentioning

confidence: 80%

Serological Prospects for Peptide Vaccines against Foot-and-Mouth Disease Virus

Parry

Ouldridge

Barnett

et al. 1989

SUMMARYAntibodies to a synthetic peptide corresponding to the 141 to 160 amino acid sequence of the protein VPI of type O foot-and-mouth disease virus (FMDV) neutralize a wider range of type O isolates than anti-virion serum. Extending this peptide at the amino terminus reduced the number of strains neutralized by the antipeptide sera. Reactions with antisera to peptides representing non-contiguous native sequences showed that it was also possible to increase the number of strains effectively neutralized. Selected substitutions of a single amino acid at position 148 markedly altered the neutralizing specificity of antibodies elicited by the 141 to 160 peptide. In particular, a peptide with an L ~ S substitution at this position induced antibodies which neutralized a type O and a type A virus equally, and guinea-pigs inoculated with it were protected from challenge with either virus. Attempts to isolate variant viruses resistant to neutralization with anti-peptide antibody indicated that these occurred at low frequency, and there was some evidence that resistance may be partially conferred by mutations outside the peptide sequence.