The Presence of Antibodies in Human Serum to Early (T) Adenovirus Antigens

The discovery by Huebner et al." 2 that hamsters bearing noninfectious tumors induced by adenoviruses develop antibodies against certain virus-specific antigens has led to the recognition of a new class of virus-induced antigens, the T antigens.By means of complement fixation (CF) and fluorescent antibody (FA) tests with the sera of tumor-bearing hamsters, it has been shown that T antigens are present in both tumors and acutely infected cells, and are produced by all human adenoviruses tested.'-7They differ from the adenovirus structural antigens (referred to here as V antigens) previously defined with convalescent and hyperimmune antisera in a number of respects: (1) the T antigens form prior to viral DNA replication in the acutely infected cell, and their formation is unaffected by treatment of the cells with 5-fluorodeoxyuridine (FUDR) or cytosine arabinoside; 6, 8, 9 (2) they do not appear to be incorporated into the mature virus particle; (3) they are generally heat-labile; and (4) they have characteristic morphologic appearances in the FA test, appearing as flecks or dots, primarily in the nucleus in the acutely infected cell.Recent evi- dence indicates that the T antigens constitute a complex group of antigens, differing from one another in morphology, breadth of reaction with heterologous types, and probably in degree of reactivity in different serologic tests.7' 10 In view of the formation of T antigens in acutely infected cells, it appeared possible that antibody responses to T antigens might be detected following acute adeno- virus infections in man.However, intensive testing by the CF procedure has yielded negative results."Since we have found the FA procedure often to be more sensitive than the CF test for detection of antibody, we applied this procedure to detection of T antibody responses in humans.It is the purpose of this paper to report that by use of the indirect FA technique, antibodies are readily detectable in human sera to adenovirus T antigens present in acutely infected cells and in certain hamster tumor cells.Sera from children acutely infected with adenovirus types 1, 3, and 7 were studied and found frequently to have antibody rises to these antigens.In addition a small percentage of serums from ad lit patients with and without cancer have antibodies which react with Ad.12 T antigens.