OBTENTION OF NEW VACCINES AGAINST HERPESVIRUSES AFFECTING PORCINE AND BOVINE (AUJESKI'DISEASE AND INFECTIOUS BOVINE RHINOTRACHEITIS).
The antibody response of pigs to glycoprotein I (gI) of pseudorabies virus was used to distinguish between infected and vaccinated pigs. We identified 6 epitopes on gI of which 5 were localised. The amino acid sequence of the 3 continuous epitopes was determined. The 2 discontinuous epitopes were more immunogenic in pigs than the 3 continuous ones. Amino acids were deleted in these epitopes by site directed mutagenesis using the polymerase chain reaction.

Vaccinia virus was used as a vector for glycoproteins gI, gIV and gH of bovine herpesvirus type 1 (BHV-1). Cattle vaccinated with these recombinant viruses were not protected against challenge with virulent BHV-1. Thus, these glycoproteins expressed by a heterologous viral vector provided insufficient immunity. Five distinct antigenic sites were found on gII of pseudorabies virus (PRV), 3 of which were located close to the transmembrane region. The gII gene was inserted into vaccinia virus and this recombinant virus induced neutralising antibodies in pigs. Six different epitopes were localised on gI of PRV, of which 3 were discontinuous. The amino acid sequences of the 3 continuous epitopes were determined. The discontinuous epitopes appeared to be the most immunogenic in pigs. Tests to detect antiboides to gI must include the discontinuous epitopes.
AT THE PRESENT STAGE OF HERPESVIRUS RESEARCH THERE IS HOPE THAT SUBUNIT VACCINES CONTAINING HERPESVIRAL GLYCOPROTEINS (GP), OR RECOMBINANT VACCINES EXPRESSING HERPESVIRAL GLYCOPROTEIN GENES WILL REPRESENT SAFE AND MORE EFFICIENT VACCINES. PRV AND BHV-1 PHYLOGENETICALLY CLOSELY RELATED VIRUSES AND PARTS OF THE GENOMES CROSS-HYBRIDIZE. THE EXPERIMENTAL STRATEGIES ARE CONVERGENT AND THEREFORE THE THREE GROUPS BELIEVE THAT CO-OPERATION WILL SPEED UP RESEARCH.
THE PROJECT FOCUSSES ON THE:

1.- IDENTIFICATION OF GP'S

2.- ROLE OF INDIVIDUAL GP'S IN VIRULENCE AND IMMUNOGENICITY

3.- LOCALIZATION OF THEIR GENES TO BE FOLLOWED BY

4.- ISOLATION OF GENES AND

5.- INSERTION OF GP GENES IN APPROPRIATE RECOMBINANT VECTORS OR EXPRESSIONS SYSTEMS.