In vitro growth characteristics of bovine herpesvirus 4 (BHV-4) as revealed by indirect immunofluorescence assay with monoclonal antibodies and polyvalent antisera.

The bovine herpesvirus 4 (BHV-4) isolate LVR-140 growing in MDBK cell cultures was investigated by indirect immunofluorescence (IF), using bovine antisera and 15 monoclonal antibodies (MAb). The cytopathogenic effect was discernible between 20 and 30 hours post inoculation (p.i.) and developed slowly as has been reported for other BHV-4 strains. According to the protein specificity as revealed by radioimmunoprecipitation and the intracellular localisation of reacting antigens as detected by IF, the MAb could be assigned to one of three groups. The initial antigen expression was first detected at 8 hours p.i. and was limited to a proportion of the infected cells only, despite the high multiplicity of infection used; infectious cell-associated progeny virus was first recognized at 12 hours p.i.