[Immunology of malignant melanomas].

The intraperitoneal diffusion-chamber-technique is a closed cell culture system in vivo. Hamster melanoma cells were capable in iso- and heterologous host animals for exponential proliferation. When the host animals had been preimmunized with melanoma cells or hamster lymphocytes a rapid cell lysis was observed in the chambers within 4 hrs after implantation. The cell numbers were reduced about 1-10% of the inoculum. After 6-10 days the cell numbers in chambers from immunized hosts slowly increased in spite of a high level of cytotoxicity in the serum of the animals.