Routine Establishment of Serial Lines of Hamster Embryo Cells Transformed by Adenovirus Type 122

Abstract

Whole hamster-embryo cells consistently underwent morphological alterations after 14–23 days in vitro when inoculated in suspension with adenovirus type 12, strain Huie, at multiplicities of 7 or more and incubated in a humidified 5% CO₂ atmosphere at 37 C. Morphological changes were never observed when cells were incubated in the absence of 5% CO₂. Altered cells were successfully cultivated for long periods and 12 serial lines were established in 12 attempts when medium NCTC 109 supplemented with 10% agamma calf serum was used. Attempts to establish serial lines on minimum essential medium in Earle's balanced salt solution with added serum were unsuccessful. Serial lines of hamster embryo cells transformed by adenovirus type 12 (ad-12) had the following inheritable characteristics: 1) small polygonal cells of uniform morphology; 2) accelerated growth rate; 3) loss of contact inhibition; 4) presence of ad-12 “T” antigen; and 5) transplantability into newborn and weanling hamsters. Virus could not be recovered from any cell line by conventional techniques. Of the 6 oncogenic ad-12 strains tested, only the prototype strain Huie was able to induce permanent morphological changes in hamster cells.