MAPPING THE ANTIGENIC STRUCTURE OF PORCINE PARVOVIRUS AT THE LEVEL OFPEPTIDES

The antigenic structure of the capsid proteins of porcine parvovirus ( PPV) was investigated. A total of nine linear epitopes were identified by Pepscan using porcine or rabbit anti-PPV antisera. No sites were i dentified with a panel of neutralising monoclonal antibodies (MAbs). A ll epitopes were located in the region corresponding to the major caps id protein VP2. Based on this information, and on analogy to other aut onomous parvoviruses, 24 different peptides were synthesised, coupled to keyhole limpet haemocyanin (KLH) and used to immunise rabbits. Most antisera were able to bind viral protein. Only peptides from the N-te rminal part of VP2 were able to induce virus-neutralising antibodies, although at low levels. A similar neutralising activity could be obtai ned in pigs. The exposure of the N-terminus was shown in full virions, both by immunoelectron microscopy and absorption experiments. It is c oncluded that in PPV, the VP2 N-terminus is involved in virus neutrali sation (VN) and peptides from this region are therefore primary target s for developing peptide-based vaccines against this virus. (C) 1998 E lsevier Science B.V. All rights reserved.