Layer chickens were immunized with three species of inactivated orthopox virus (vaccinia virus, calpox virus and cowpox virus). Antibodies (IgY) were purified from egg yolks by improved polyethylene glycol precipi...Layer chickens were immunized with three species of inactivated orthopox virus (vaccinia virus, calpox virus and cowpox virus). Antibodies (IgY) were purified from egg yolks by improved polyethylene glycol precipitation. The development of IgY directed against orthopox virus antigens was followed by immunofluorescence assay, plaque reduction neutraliztion test and immunoelectron microscopy. Cross-reactivity of two IgY antibodies with cells infected by the different strains of the pox viruses was also investigated by different methods (immunofluorescence assay, plaque reduction neutraliztion test and Western blot). Even in very high dilutions in immunofluorescence assay (titres up to 1:10^6 and 1:10^5, respectively) and persisted on a plateau over 10 months after four booster injections, it was showed that anti-vaccinia virus IgY and anti-calpox virus IgY were positive. Neutralizing activity and ultra-structural detection of antigen with gold-labelled antibodies were respectively observed in plaque reduction neutralization test and immunoelectron microscopy. Western blot analysis revealed specific binding of IgY to virus proteins. Thus, there was cross-reactivity between different orthopox viruses. Finally, orthopox virns-specific IgY antibodies bounded magnetic beads (Dynabead) were used to concentration of orthopox viruses. This study suggests that anti-pox virus IgY could serve as a useful tool for orthopox viruses diagnosis.展开更多
文摘Layer chickens were immunized with three species of inactivated orthopox virus (vaccinia virus, calpox virus and cowpox virus). Antibodies (IgY) were purified from egg yolks by improved polyethylene glycol precipitation. The development of IgY directed against orthopox virus antigens was followed by immunofluorescence assay, plaque reduction neutraliztion test and immunoelectron microscopy. Cross-reactivity of two IgY antibodies with cells infected by the different strains of the pox viruses was also investigated by different methods (immunofluorescence assay, plaque reduction neutraliztion test and Western blot). Even in very high dilutions in immunofluorescence assay (titres up to 1:10^6 and 1:10^5, respectively) and persisted on a plateau over 10 months after four booster injections, it was showed that anti-vaccinia virus IgY and anti-calpox virus IgY were positive. Neutralizing activity and ultra-structural detection of antigen with gold-labelled antibodies were respectively observed in plaque reduction neutralization test and immunoelectron microscopy. Western blot analysis revealed specific binding of IgY to virus proteins. Thus, there was cross-reactivity between different orthopox viruses. Finally, orthopox virns-specific IgY antibodies bounded magnetic beads (Dynabead) were used to concentration of orthopox viruses. This study suggests that anti-pox virus IgY could serve as a useful tool for orthopox viruses diagnosis.