Demonstration of host resistance against isotransplantation of lymphomas induced by the Gross agent.

It was found that a state of relative resistance can be built up in highly inbred skincompatible C3H mice against the isotransplantation of lymphomas recently induced in the same strain by the Gross virus. Resistance could be built up in two different ways: by pretreating the recipients with homografts of other Gross lymphomas, in duced in genetically incompatible mice, or with sub-threshold doses of cells from the same isologous lymphoma. The resistance was relatively weak in comparison with the previously demonstrated antigenicity of methylcholanthrene-induced sarcomas and polyoma-induced tumors. There appears to be partial or complete cross-resistance between different lymphomas induced by the Gross virus.