Immunity to Transplantable Nitrosoureahyphen;Induced Neurogenic TumorsIIperiod; Immunoprophylaxis of Tumors of the Brain

摘要

An effective method was sought to immunize rats against the growth of intra-ccrebrally (IC) injected T9tumor, a gliosarcoma cell line. Rats which were immunized with either 106T9cells mixed with 0.14 mgC. parvum, or 107irradiated T9cells showed tumor immunity to intradermal (ID) transplantation. However, to obtain tumor immunity to an IC challenge of T9cells, rats initially had to reject an ID challenge of T9cells. After sequential rejections of ID challenges of as many as 107cells, a high degree of immunity was obtained, allowing rejection of up to 5 times; 106T9cells injected IC. Spleen cells from highly immunized rats mixed with T9cells at a ratio of 1:25 (tumor: spleen) destroyed T9tumor cells in a Winn test. Normal spleen cells had no effect on tumor growth. We conclude that: 1) T9cells are moderately immunogenic, 2) an effective method of immunization of CDF rats against ID transplanted T9cells is 106T9cells with 0.14 mgC. parvumor 107irradiated T9cells, 3) a higher degree of tumor immunity is necessary to reach the brain than is needed to reach the periphery, and 4) spleen cells of highly immunized rats are cytotoxic to T9tumor cells.