CHARACTERIZATION OF CANINE HERPESVIRUS GLYCOPROTEIN-C EXPRESSED BY A RECOMBINANT BACULOVIRUS IN INSECT CELLS

The gene encoding the canine herpesvirus (CHV) glycoprotein C (gC) hom ologue has been identified by sequence homology analyses with other we ll studied herpesviruses. Previously, we have identified three CHV gly coproteins, gp145/112, gp80 and gp47 using a panel of monoclonal antib odies (MAbs). To determine which CHV glycoprotein corresponds to gC, a recombinant baculovirus which contains the putative CHV gC structural gene under the baculovirus polyhedrin promoter was constructed. The r ecombinant baculovirus expressed gC-related polypeptides (44-62 kDa); which reacted only with MAbs against CHV gp80, indicating that the pre viously identified CHV gp80 is the translation product of the gC gene. The baculovirus expressed gC was glycosylated and transported to the surface of infected cells. At least seven neutralizing epitopes were c onserved on the gC produced in insect cells. It was found that the rec ombinant baculovirus infected cells adsorbed murine erythrocytes as is the case for CHV-infected cells. The hemadsorption activity was inhib ited by heparin, indicating that the CHV gC binds to heparan sulfate o n the surface of murine erythrocytes. Mice immunized with the recombin ant gC produced strong neutralizing antibodies. Our results suggest th at CHV gC produced in insect cells may be useful as a subunit vaccine to control CHV infections. Copyright (C) 1996 Elsevier Science B.V.