Malignant transformation in a tissue culture infected with a mouse leukemia virus (brief report).

Abstract

A culture of normal spleen and thymus of suckling Timco (Texas Inbred Mouse Company, Houston, Texas) Swiss mice was initiated in our laboratory in 1964. Normal Timco Swiss mouse embryo cells were added to the 29th passage of this culture in order to improve growth ("rejuvenation"). Since then, the culture grows luxuriantly. This culture has been infected with a mouse passage line of the Rauscher mouse leukemia virus and the cells have subsequently been passed serially. A portion of the original culture was left uninfected but the same normal mouse embryo cells were added also to this culture; the cells of this line have also been passed serially, applying medium and techniques identical with those used for the infected line (1). The infected culture, referred to as the parent line, is in the 154th subculture. The culture produces typical murine leukemia virus particles and the cs~oplasm of the virus-producing cells stains apple green with antiviral antibody, by the indirect .fluorescent ant ibody technique (2). The cells remained elongated and grew in orderly sheets up to about 90 serial passages. Bioassays done in young Timco Swiss mice resulted in a spectrum of malignant diseases and related conditions. These are as follows : (i) Erythroblastic and reticulum cell leukemia, (if) malignant lymphoma re-