Recombinant feline herpesvirus type 1 expressing immunogenic proteins inducible virus neutralizing antibody against feline calicivirus in cats.

In this study, an entire open reading frame encoding the capsid protein of feline calicivirus (FCV) F4 strain was inserted into the deletion locus (SmaI site) of the thymidine kinase (TK) deficient mutant (C7301dlTK) of feline herpesvirus type 1 (FHV-1) and the resulting recombinant virus was designated as C7301dlTK-Cap. Expression of the FCV antigens by C7301dlTK-Cap was confirmed by indirect immunofluorescence assay and immunoblot analysis. To assess whether the recombinant virus can induce virus neutralizing (VN) antibody against FCV in the natural host, three cats were inoculated intranasally and orally with C7301dlTK-Cap (two cats) or C7301dlTK (one cat). As a result, sera collected from cats inoculated with the C7301dlTK-Cap possessed VN antibody against FCV. This recombinant virus is expected as a new polyvalent recombinant vaccine against FHV-1 and FCV infections.