[Augmentation of specific anti-tumor immunity by immunization with xenogenized tumor cells and its application to the experimental cancer treatment (author's transl)].

It is already known that immunization with viable tumor cells which had been artificially infected with Friend virus (xenogenized tumor cells), one of murine leukemia viruses, produced a strong anti-tumor immunity against the identical non-infected tumor in comparison with that with mitomycin C-treated or irradiated non-infected tumor cells. Lethal tumor dose which could kill 50% of rats (LTD50) was increased up to 1,000 times by the immunization with the viable xenogenized tumor cells. In this presentation, procedure how to augment immunogenicity of the xenogenized tumor cells was examined. Intradermal single immunization with the xenogenized tumor cells (third passage generation through Friend virus-tolerant rats) inhibited most strongly the subcutaneous growth of non-xenogenized tumor; LTD50 was markedly increased more than 10,000 times. In addition, the intradermal active immunization with the viable xenogenized tumor cells followed by the irradiated non-xenogenized tumor cells resulted in 30.8% of complete regression of the tumor subcutaneously transplanted.