Response of Simian Virus 40-Transformed Cell Lines and Cell Hybrids to Superinfection with Simian Virus 40 and Its Deoxyribonucleic Acid

Abstract

Whereas normal human and monkey cells were susceptible both to intact simian virus 40 (SV40) and to SV40 deoxyribonucleic acid (DNA), human and monkey cells transformed by SV40 were incapable of producing infectious virus after exposure to SV40, but displayed susceptibility to SV40 DNA. On the other hand, mouse and hamster cells, either normal or SV40-transformed, were resistant both to the virus and to SV40 DNA. Hybrids between permissive and nonpermissive parental cells revealed a complex response: whereas most hybrids tested were resistant, three of them produced a small amount of infectious virus upon challenge with SV40 DNA. All were resistant to whole virus challenge. The persistence of infectious SV40 DNA in permissive and nonpermissive cells up to 96 hr after infection was ascertained by cell fusion. The decay kinetics proved to be quite different in permissive and nonpermissive cells. Adsorption of SV40 varied widely among the different cell lines. Very low adsorption of SV40 was detected in nonsusceptible cells with the exception of the mKS-BU100 cell line. A strong increase in SV40 adsorption was produced by pretreating cells with polyoma virus. In spite of this increased adsorption, the resistance displayed by SV40-transformed cells to superinfection with the virus was maintained.

Properties of an sv40‐transformed african green monkey kidney (bsc‐1) cell line

“…It has been shown (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971) that different SV40transformed monkey and human cell lines are all superinfectable by SV40 DNA. A certain disagreement exists, however, on their efficiency in initiating SV40 D N A replication and in producing infectious virus.…”

“…In vitro transformation of African green monkey kidney cells by SV40 has been reported by Fernandes et al (1 969, Wallace (1 967), Koprowski et al (1967) and Margalith et al (1969). Only the transformed cell line established by Koprowski et a/. (GMK-Eva) and that established by were extensively studied (Koprowski et al, 1967;Jensen and Koprowski, 1969;Swetly et al, 1969;Margalith et al, 1969Margalith et al, , 1970Barbanti-Brodano et al, 1970;Rapp and Trulock, 1970;Sauer and Hahn, 1970 a, 6; Kit and Dubbs, 1971). The most interesting finding is that they are susceptible to superinfection by SV40 virus or viral DNA (Swetly et a/., 1969;Barbanti-Brodano et al, 1970;Kit and Dubbs, 1971).…”

“…This is also the case for SV40-transformed semipermissive human cells but not for SV40transformed non-permissive mouse, hamster, rat, cat and dog cells (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971). A certain disagreement exists, however, on the efficiency of the transformed monkey and human cells in initiating virus DNA replication and in producing infectious virus following superinfection (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971). Because of the relevance of these observations to the mechanism of transformation of animal cells by SV40, more information on transformed permissive and semi-permissive cells is desirable.…”

“…Only the transformed cell line established by Koprowski et a/. (GMK-Eva) and that established by were extensively studied (Koprowski et al, 1967;Jensen and Koprowski, 1969;Swetly et al, 1969;Margalith et al, 1969Margalith et al, , 1970Barbanti-Brodano et al, 1970;Rapp and Trulock, 1970;Sauer and Hahn, 1970 a, 6; Kit and Dubbs, 1971). The most interesting finding is that they are susceptible to superinfection by SV40 virus or viral DNA (Swetly et a/., 1969;Barbanti-Brodano et al, 1970;Kit and Dubbs, 1971). This is also the case for SV40-transformed semipermissive human cells but not for SV40transformed non-permissive mouse, hamster, rat, cat and dog cells (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971).…”

“…The most interesting finding is that they are susceptible to superinfection by SV40 virus or viral DNA (Swetly et a/., 1969;Barbanti-Brodano et al, 1970;Kit and Dubbs, 1971). This is also the case for SV40-transformed semipermissive human cells but not for SV40transformed non-permissive mouse, hamster, rat, cat and dog cells (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971). A certain disagreement exists, however, on the efficiency of the transformed monkey and human cells in initiating virus DNA replication and in producing infectious virus following superinfection (Swetly et al, 1969;Barbanti-Brodano et al, 1970;Kit et al, 1970;Kit and Dubbs, 1971).…”