TY - JOUR
T1 - Replication of two porcine parvovirus isolates at non-permissive temperatures
AU - Choi, C. S.
AU - Joo, H. S.
AU - Molitor, T. W.
PY - 1990/9
Y1 - 1990/9
N2 - Previous studies have shown that replication in vitro of the porcine parvovirus (PPV) isolate, KBSH, was restricted at 39°C but not at 37°C. In contrast, replication of the Kresse isolate was restricted at 37°C but not at 39°C. In this study, Kresse and KBSH isolates were passaged up to ten times in swine testicle (ST) cells at non-permissive temperatures, and at subsequent passage viral protein synthesis, viral DNA synthesis, and progeny virus were evaluated. KBSH became adapted for replication at 39°C upon serial passages, displaying an appreciable increase in viral progeny, viral polypeptides, and viral DNA concentration. This finding was also observed with Kresse virus isolate continuously passaged at 37°C. Neither isolate became adapted for replication at 32°C. In an attempt to examine the effect of in vitro passage at non-permissive temperatures on pathogenicity in swine, KBSH passaged 10 times either at 37°C or 39°C was inoculated into swine fetuses. Two of four fetuses inoculated with 39°C-passaged KBSH were dead and hemorrhagic or mummified. All four fetuses inoculated with 39°C-KBSH contained viral antigen and viral DNA. In contrast, fetuses inoculated with 37°C-passaged KBSH, or with cell culture fluid were normal in appearance. Viral antigen and viral DNA were not demonstrated in fetuses inoculated with 37°C-KBSH or cell culture fluids. These findings suggest the possibility that the ability to replicate at 39°C is associated with virulence in swine fetuses.
AB - Previous studies have shown that replication in vitro of the porcine parvovirus (PPV) isolate, KBSH, was restricted at 39°C but not at 37°C. In contrast, replication of the Kresse isolate was restricted at 37°C but not at 39°C. In this study, Kresse and KBSH isolates were passaged up to ten times in swine testicle (ST) cells at non-permissive temperatures, and at subsequent passage viral protein synthesis, viral DNA synthesis, and progeny virus were evaluated. KBSH became adapted for replication at 39°C upon serial passages, displaying an appreciable increase in viral progeny, viral polypeptides, and viral DNA concentration. This finding was also observed with Kresse virus isolate continuously passaged at 37°C. Neither isolate became adapted for replication at 32°C. In an attempt to examine the effect of in vitro passage at non-permissive temperatures on pathogenicity in swine, KBSH passaged 10 times either at 37°C or 39°C was inoculated into swine fetuses. Two of four fetuses inoculated with 39°C-passaged KBSH were dead and hemorrhagic or mummified. All four fetuses inoculated with 39°C-KBSH contained viral antigen and viral DNA. In contrast, fetuses inoculated with 37°C-passaged KBSH, or with cell culture fluid were normal in appearance. Viral antigen and viral DNA were not demonstrated in fetuses inoculated with 37°C-KBSH or cell culture fluids. These findings suggest the possibility that the ability to replicate at 39°C is associated with virulence in swine fetuses.
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U2 - 10.1007/BF01316676
DO - 10.1007/BF01316676
M3 - Article
C2 - 2222184
AN - SCOPUS:0025053843
SN - 0304-8608
VL - 113
SP - 235
EP - 244
JO - Archives of Virology
JF - Archives of Virology
IS - 3-4
ER -