COMPLEMENT-FIXING ANTIGENS IN TISSUE CULTURES OF AVIAN LEUCOSIS VIRUSES.

Avian sarcoma and leucosis virus preparations grown in chick embryo tissue cultures contained complement-fixing antigens, which were demonstrated with the use of antiserums from hamsters carrying sarcomas induced by the Schmidt-Ruppin strain of avian sarcoma virus. The complement-fixing antigens shared by three different strains of avian leucosis and one strain of avian sarcoma viruses were largely "soluble" (having failed to sediment when centrifuged at 59,364g for 70 minutes). Sedimented particles, presumably virus particles, contained the common sarcoma-leucosis antigen as well.