Changes in Simian Virus 40 Susceptibility and Chromosome Numbers During Long-Term Cultivation of BS-C-1 Cells

Abstract

Cytogenetic studies were performed on cultures of an established Cercopithecus monkey kidney cell line, BS-C-1. The susceptibility of each culture to simian virus (SV40) was determined during long-term cultivation by the production of a cytopathic effect in the culture. The chromosome number of BS-C-1 cells cultured for more than 60 subcultures often increased from the diploid to the near-tetraploid region. In some instances, this change was accompanied by a loss of susceptibility of the cells to SV40 infection. Sublines of BS-C-1 cells were isolated and compared to their parent cultures. These sublines retained their diploid chromosome numbers, while the chromosome number of the parent cultures increased from the diploid to the near-tetraploid region. In one culture the parent line, but not the sublines, showed a loss of susceptibility to SV40 infection. In the second culture, both the parent line and the sublines were less susceptible to SV40. Possible reasons for this variability are discussed.