Systemic immunity against a murine colon tumor (CT-26) produced by immunization with syngeneic cells expressing a transfected viral gene product.

We have previously shown that CT-26 tumor cells expressing the transfected hemagglutination antigen of influenza virus elicit an immune response in syngeneic hosts that is cross-protective against an s.c. challenge with non-transfected parental cells. Since CT-26 is a murine colorectal carcinoma we sought to determine whether the same immuno-protective effect could be achieved after a challenge with parent tumor cells injected into the usual sites of colon tumor growth and metastasis. We now show that the protection afforded by this immunization protocol is systemic and that animals can be protected against tumor growth in the cecum, lymphatics of the mesentery, liver and lung.