Mechanisms of immunologic eradication of a syngeneic guinea pig tumor. I. Quantitative analysis of adoptive immunity.

Adoptive immunity against a syngeneic hepatoma (line-10) of Sewall-Wright inbred strain 2 guinea pigs was analyzed by a two-dimensional titration of iv transferred immune lymphoid cells versus intradermal tumor challenges. Tumor resistance increased exponentially as a function of the number of immune lymphoid cells transferred. Within the tumor challenge doses analyzed, suppression of tumor growth mediated by the transferred immune lymphoid cells appeared to be independent of the primary immune response in the recipient. Quantitatively, rejection of a given number of tumor cells reflected the number of transferred immune cells and was independent of the presence of the same tumor at other skin sites. There was no evidence indicating that transferred immune cells were attracted specifically to the tumor inoculation site. The number of tumor cells that could be rejected at a skin site by adoptive immunity was greater than the estimated number of immune lymphoid cells present at the challenge site.