Susceptibility of various cell lines to virulent an attenuated strains of pseudorabies virus at supraoptimal temperature.

Replication of virulent and attenuated strains of pseudorabies virus (PRV) at supraoptimal temperature was studied in rabbit lung (ZP), pig kidney (PS), and BHK-21 cells adapted and non-adapted to 40 degrees C and L, HeLa and human amniotic (Am) cells non-adapted to 40 degrees C. The temperature of 40 degreeC did not influence the type cytopathic effect (CPE) in either adapted or non-adapted cells. According to the susceptibility at 40 degrees C the cells could be divided into three groups: cells permissive for all PRV strains (adapted and non-adapted ZP and non-adapted BHK-21 and PS); cells non-permissive for all PRV strains (L, HeLa and Am); and cells permissive for virulent and non-permissive for attenuated PRV strains (adapted BHK-21 and PS). The virus titres in permissive cells at 40 degrees C did not differ from those obtained at 37 degrees C. The attenuated strain CK-PRV X was found to be a tsmutant of PRV with host range character.