Critical Factors in Successful Recovery of Rous Sarcoma Virus from Turkey Tumors

Studies of tumor cell cultures with antiviral antibody showed that most of the cell-associated virus and viral antigen were found at the cell membrane and were thus accessible to the effect of neutralizing antibody. Humoral antibody present in tumor tissue neutralized cell-associated virus in vivo and thus rendered the tumor cells temporarily noninfectious. When these cells were grown in vitro in the absence of antibody, virus eventually reappeared. However, the time of reappearance, amount of virus produced, and persistence of virus in such cultures depended upon the amount of virus used to produce the tumor.