Specific Chromosome Aberrations in Cells Persistently Infected with Type 2 Hemadsorption Virus

A clonal strain derived from HeLa-S3 cells persistently infected with hemadsorption type 2 virus (S3/HA2) has general properties comparable to those previously described for persistently infected wild-type HeLa cells (HeLa/HA2) except that partial cytopathic changes were observed in the process of establishing persistent infection in S3 cells. A chromosomal analysis was conducted on S3/HA2 cells and S3 cells freshly infected with the virus. The modal number of chromosomes in S3 HA2 cells and freshly infected S3 cells was shown to be 68, hypotriploidy as also observed in control S3 cells. The karyotypic changes, however, occurred in virtually 100% of cells. The chromosomal changes are characterized by the deletion of one of the chromosome 22 and the supposed X-chromosome and the addition of each one chromosome to the chromosome 19 and 20. Karyotypic change as observed in S3/HA2 cells was obtained in S3 cells as early as 24 hours after infection. It was suggested that these changes are not due to the selection of particular cells present in the uninfected S3 culture hut to the virus infection itself.