PROTECTIVE AND CURATIVE POTENTIAL OF VACCINATION WITH INTERLEUKIN-2-GENE-TRANSFECTED CELLS FROM A SPONTANEOUS MOUSE MAMMARY ADENOCARCINOMA

The potential of interleukin 2-gene-transfected tumor cells to prevent tumor growth and cure established tumors was evaluated using cells fr om a spontaneous, invasive, and metastasizing mouse mammary adenocarci noma. Tumor cells engineered to secrete interleukin 2 initially trigge r a local inflammatory reaction that leads to inhibition of establishe d parental adenocarcinomas, as well as an antigenically unrelated fibr osarcoma. The ensuing systemic immunity selectively inhibits subsequen t parental cell challenges and cures established parental adenocarcino mas and their lung metastases, although less effectively as the neopla stic mass increases. Multiple injections of interleukin 2-gene-transfe cted tumor cells may thus be considered a new form of vaccination in t he management of minimal residual disease and incipient metastases.