Abstract
Human papillomavirus type 16 (HPV16) DNA cloned in the expression vector pSV2-neo has been shown to be maintained in transfected monkey kidney cells as an autonomously replicating episome at a level of 2 to 10 copies per cell. Integration of pSV2-neo/HPV16 DNA with the host genome occurred in transfected mouse fibroblasts. Neither type of cell appeared to be phenotypically transformed.