We have reviewed the experimental results which indicate that endogenous type I interferon
(IFN) present either constitutively or possibly induced by the tumor plays an important role in
limiting the development of transplantable tumors in mice. Thus, treatment with potent
polyclonal neutralizing antibodies to IFN α/β markedly enhanced the subcutaneous growth,
invasiveness and metastases of xenogeneic tumor cells (uninfected or infected with RNA or
DNA viruses) in athymic nude mice; enhanced the intraperitoneal transplantability of six …