Transformation of Rodent Cells by Simian Adenovirus SA-7 ∗

Abstract

Summary

A clone of the hamster cell line NIL-2 cells and primary rat embryo cells were transformed by simian adenovirus SA-7. The transformed NIL-2 cells formed foci of multilayered growth in monolayer cultures under agar and colonies when suspended in agar medium. The transformed rat cells formed foci under liquid medium. Cell lines were derived from both NIL-2 and rat transformed cells. A virus stock containing 1.8 × 10⁹ particles and 2.5 × 10⁸ PFU/ml contained 8 × 10³ FFU/ml in NIL-2 cells and 4.6 × 10² FFU/ml in rat embryo cells. Approximately 3.1 × 10⁴ infectious units were required to induce one focus in NIL-2 cells and 5.4 × 10⁵ infectious units were required in rat embryo cells. The transformed NIL-2 cells contained SA-7-specific tumor antigens and RNA. They formed colonies in agar and induced tumors in hamsters with characteristic adenovirus-induced tumor pathology.

SA-7 transforms NIL-2 more efficiently than human adenovirus types 7 or 12; it transforms rat cells at approximately the same efficiency as types 1 and 12.