[Possibilities of immunologic management of Brown-Pearce carcinoma in rabbits]

The efficacy of the active specific immunotherapy and immune prophylaxis against the Brown Pearce carcinoma in rabbits was tested. The tumor cells taken as antigens were either untreated or treated with Mitomycin C combined or not with vibrio-cholerae-neuraminidase. The immune prophylaxis using tumor cells prepared this way proved to be very effective. In contrast, immunotherapy of rabbits with tumors was not effective, even when immunization was started directly after transplantation. Possible mechanisms were analyzed in-vitro and in-vivo assays. The cellular reactivity of sensitized spleen cells was positive, the humoral reaction was weaker. This kind of reaction could only be demonstrated with tumor cells pretreated with vibrio-cholerae-neuraminidase. The findings shall only be discussed with respect to the possible causes of ineffective immunotherapy.