Immunization by irradiated whole cells or cell extracts against an experimental bladder tumor.

A tissue culture cell line has been developed from the MBT-2, a carcinogen induced bladder tumor of C3H/HeN mice. The culture-adapted cells retained the capacity to induce progressive tumors in syngeneic mice. Amputation-challenge experiments with live cells showed that MBT-2 induces transplantation immunity. Immunization with irradiated MBT-2 cells or hypotonic membrane preparations from this tumor protected the animals against challenge with viable MBT-2 cells. Intraperitoneal administration of bacille Calmette Guérin failed to protect against tumor development and may have adversely affected the immunoprotection yielded by tumor extracts.