Effect of a DNA tumour virus on antibody forming cells in neonatally infected hamsters.

Abstract

LEUKAEMOGENIC viruses, such as Friend, Rauscher or Moloney virus, may markedly suppress the immune responses of infected mice, both at the cellular and humoral levels1–10. AKR mice developing spontaneous leukaemia also have a marked suppression of serum antibody formation preceding clinical symptoms11. Several current theories of carcinogenesis suggest that such deficiencies of specific immunological competence may be a necessary but not exclusive prerequisite for tumour development12–16. In this regard, the induction of tumours by viruses other than those associated with murine leukaemia may also depend on an inadequate immune system and/or induction of specific immunological tolerance. Because most tumour viruses induce neoantigens in infected cells, it seems probable that an immunocompetent individual would respond to the virus induced antigens15. Loss of immunological competence could be related to development of the tumours. This study was undertaken to determine if a non-leukaemia DNA tumour virus could affect the immunological responsiveness of experimental animals. For this purpose, SV40 tumour virus was inoculated into newborn hamsters and their subsequent immune response to sheep erythrocytes was determined at the serum and cell level, using the haemolytic plaque assay in agar gel and serological procedures. The responses of non-infected hamsters were determined simultaneously.