EXPRESSION OF BOVINE HERPESVIRUS-1 GLYCOPROTEIN GIII BY A RECOMBINANT BACULOVIRUS IN INSECT CELLS

Bovine herpesvirus 1 (BHV-1) glycoprotein gIII functions both as a major virus attachment protein and haemagglutinating protein. Here we constructed recombinant baculovirus incorporating the BHV-1 gIII coding sequence to characterize the expression, function and immunogenicity of the glycoprotein in insect cells. The recombinant gIII had an M(r) of 72K and seemed to form homodimers. The gIII was expressed on the surface of insect cells and a rosette formation assay demonstrated haemadsorbing activity of the glycoprotein. Antigenic authenticity of the recombinant gIII was confirmed by a panel of monoclonal antibodies specific for the glycoprotein produced in mammalian cells. Antisera raised to recombinant gIII neutralized the infectivity of BHV-1. These data suggest that recombinant gIII produced in insect cells may be a useful immunogen in a BHV-1 vaccine.