Antibody to virion structural proteins in mammals bearing avian sarcoma virus-induced tumors.

The production of antibody to virion structural proteins was examined in rabbits and hamsters bearing tumors induced by avian sarcoma virus (ASV). Antibody activity was analyzed by the immunoprecipitation of polypeptides from preparations of radiolabeled ASV virions. Antipolymerase and antiglycoprotein activities were monitored by inhibition of the enzyme activity of virion polymerase and by neutralization of focus formation by group D ASV, respectively. All sera from hamsters bearing primary ASV-induced tumors had antibody against the viral gs antigens, but no antipolymerase or antiglycoprotein activity was detectable. Most sera from hamsters bearing tumors induced by injection of cloned hamster tumor cells displayed anti-gs activity, and in addition, some sera exhibited anti-polymerase activity as well. All sera from rabbits bearing primary tumors contained antibody against the gs antigens and the virion polymerase, and some of these sera were shown to have antibody against the virion glycoprotein, gp85, as well.