Construction of a full-length infectious cDNA clone of swine vesicular disease virus strain NET/1/92 and analysis of new antigenic variants derived from it
Jmj. Rebel et al., Construction of a full-length infectious cDNA clone of swine vesicular disease virus strain NET/1/92 and analysis of new antigenic variants derived from it, J GEN VIROL, 81, 2000, pp. 2763-2769
The Dutch swine vesicular disease virus (SVDV) isolate NET/1/92 was one of
the first isolates belonging to a new SVDV antigenic group. This strain was
completely sequenced and was shown to have 93% similarity with the UKG/27/
72 isolate. To enable antigenicity, replication, maturation and pathogenici
ty studies of NET/1/92, an infectious full-length cDNA clone, designated pS
VD 146, was prepared. The in vitro and in vivo biological properties of the
virus derived from pSVD 146 were studied by analysing antigenicity, plaque
morphology, growth curves and virulence in pigs. The epitopes of newly pre
pared monoclonal antibodies were roughly mapped by fusion-PCR. Fine mapping
of epitopes at the amino acid level was achieved by introducing single ami
no acid mutations in pSVD 146. Two new amino acids important in epitope for
mation were located in VP1; one was mapped in the C-terminal end and the se
cond is thought to be located in the H-1 loop. Growth curve and plaque size
s in vitro were similar between virus derived from pSVD146 and the parent w
ild-type virus. In virulence studies in pigs, the lesions score, neutraliza
tion titres and the seroconversion rates were comparable between virus deri
ved from pSVD146 and the parent strain. Since virus derived from pSVD146 ha
d the same biological properties as the parent strain NET/1/92, the full-le
ngth infectious cDNA clone pSVD146 will be very useful in studies of the an
tigenicity, virulence, pathogenesis, maturation and replication of SVDV.