Loss of Transplantability and Induction of Immunoprotection by Mouse Ascites Tumor Cells in Tissue Culture

Abstract

A tumor model system has been developed based on the loss of transplantability by long-term cultures of ascites tumor cells. Nontumorigenic 6C3HED cells were completely unable to produce tumors in both normal and X-irradiated mice. Some recovery of transplantability was achieved by suspending nontumorigenic 6C3HED cells in sterile-filtered ascites fluid from the Ehrlich-Lettré tumor. The nontumorigenic 6C3HED cells proved highly immunoprotective in mice since they induced complete protection against challenge with 106 virulent cells.