SPECIFIC ADENOVIRUS COMPLEMENT-FIXING ANTIGENS IN VIRUS-FREE HAMSTER AND RAT TUMORS.

Abstract

Although tumors induced in hamsters by adenovirus types 12 and 18 do not contain demonstrable infectious virus, turmorous animals develop high-level complement-fixing (CF) antibodies reactive with homotypic adenovirus tissue culture antigens.' Likewise, hamsters carrying transplants of these noninfectious tumors show comparable CF antibody responses. Hamsters which received virus or transplanted tumor tissue, but in which progressive tumor growth did not occur, did not develop CF antibody., 2 In contrast to human CF antibody responses to adenovirus infections, in which the antibody is primarily formed against the group reactive A3 or L4 soluble antigen, the antibodies in the tumorous hamsters are essentially type-specific and are presumably reactive with antigens similar to the C3 or E4 soluble antigens. Thus, sera from hamsters with tumors induced by type 12 react in high titer with type 12 tissue culture antigen, are somewhat less reactive with type 18 antigen, and give no reaction with the other 26 human adenovirus types. Virus-neutralizing antibodies also develop in hamsters with primary and transplanted tumors, but only in those with highest levels of CF antibody. 2 This report describes the direct demonstration of virus-specific CF antigens in the noninfectious or virus-free hamster tumors induced by adenovirus types 12 and 18, as well as in transplanted tumors' and tissue culture cell lines derived therefrom. Also, we describe the induction of tumors in rats by type 12, with comparable findings of noninfectious virus-specific antigens and antibodies in the tumorous animals. Preliminary information on specific CF antigens in hamster tumors induced by SV40 and Rous viruses is also plesented.