B-cell epitopes of canine parvovirus: distribution on the primary structure and exposure on the viral surface

Abstract

Ten antigenic sites on canine parvovirus (CPV) were mapped with a complete set of overlapping nonapeptides of the capsid proteins VP1 and VP2: five of these sites were recognized by sera from CPV-infected dogs, three were recognized by a rabbit anti-CPV antiserum, and two were recognized by murine monoclonal anti-CPV antibodies. A region covering the first 21 amino-terminal amino acid residues of VP2 was recognized by three sera from infected dogs, one neutralizing rabbit antiserum, and one neutralizing murine monoclonal antibody. Immunoabsorption experiments with full virions indicated that at least 6 of the 10 antigenic sites are located on the surface. Of these six, three sites occur in the amino terminus of VP2. When superimposed on the three-dimensional structure of canine parvovirus (J.

Peptide vaccine against canine parvovirus: identification of two neutralization subsites in the N terminus of VP2 and optimization of the amino acid sequence

“…The shortest N-terminal sequence capable of NT induction was nine amino acid residues (peptide 3L9). The absence of Gly-10 and Gly-11 in peptide 11L13 (CysGQPAVRNERATGS) also explains why now (Table 1), and previously (13), no neutralizing activity was obtained despite recognition by neutralizing monoclonal antibody 3C9 (8,13). Surprisingly, in general, the antipeptide response in mice was consistently lower than that in rabbits ( Table 2).…”

“…Peptide 7L15 was especially effective in inducing neutralizing activity. Peptide 1L15 contained the antigenic core (SDGAVQ, residues 2 to 7 of VP2) recognized by some CPV-infected dog sera (8). Also, from PEPSCAN analyses with multiple-length solid-phase peptides and antipeptide antisera it was deduced that the main reactivity of the antibodies elicited by these peptides was directed against the amino acid sequence DGGQPAV, residues 9 to 15 (which are part of the overlapping sequence).…”

“…However, the homology with other parvoviruses, including porcine parvovirus, is lower (3). This domain has become important for several reasons: (i) it is involved in the MVM entry to the cell (19), (ii) it contains an epitope recognized by the CPV neutralizing monoclonal antibody 3C9 (8,13), and (iii) immunization with a mixture of two partially overlapping pentadecapeptides (1L15, 7L15) derived from this region has been able to provide full protection in target animals (dogs and minks) against a challenge with a lethal dose of virulent CPV or mink enteritis virus, respectively (7,10). A major advantage of using the N-terminal peptides as a vaccine is the lack of reactivity of naturally infected dog sera; only 3 of 16 dogs tested gave a positive reaction against this region.…”

“…However, we can exclude some possibilities such as aggregation, which was not observed by immunoelectron microscopy experiments using monoclonal and polyclonal antibodies against the N terminus (6a). This result is consequent with a limited exposure of this domain in the viral capsids (5,8). The situation for CPV could be similar to poliovirus, for which the neutralization is due to the binding of antibodies to VP1 internal sequences, which become exposed as the virus structure breathes at 37ЊC in a reversible exposure (12).…”

Basic aspects of immunomodulation through active immunization

“…This approach has been used to define useful immunogenic peptides for pathogens including foot-and-mouth disease virus (FMDV) , HIV, corona viruses and herpes virus (Meloen and Barteling, 1986;Goudsmit et al, 1988;Middeldorp and Meloen, 1988;Jacobs et al, 1990;Posthumus et al, 1990;Langedijk et al, 1993). It also allowed us to develop the first synthetic peptide vaccine which gives full protection against a viral disease (canine parvovirus) in the target animal itself (Langeveld et al, 1993;.…”