title: Characterization of suppressor cells in mice bearing syngeneic mastocytoma.
abstract: Suppressor cells from syngeneic P815 mastocytoma-bearing DBA/2 mice that inhibit in vitro generation of specific anti-tumor cytotoxicity were characterized. Suppressive activity was almost completely eliminated by treating suppressive spleen cells with anti-theta serum and complement. Treatment with anti-mouse lg serum and complement or with carbonyl iron did not affect their suppressive activity. When suppressive thymocytes from P815 tumor-bearing DBA/2 mice were tested for their capacity to inhibit the generation of cytotoxicity against L1210 cells, a leukemia line in DBa/2 mice, they did not affect the activity, indicating that the supressor cells in the thymocytes of P815 tumor-bearing mice are specific to the tumor. When Ficoll-Hypaque density cell separation was carried out with cytotoxic spleen cells and suppressive spleen cells from 815 tumor-bearing mice, the dense fraction was enriched for kiler cells whereas the suppressive activitty was mainly recovered in the light fraction. Therefore, killer cells and suppressor cells in P815 tumor-bearing mice are thought to be distinct populations.
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D003601:Cytotoxicity Tests, Immunologic; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes; D005260:Female; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D007939:Leukemia L1210 / Q000276:immunology; D012515:Mast-Cell Sarcoma / Q000276:immunology*; D051379:Mice; D008811:Mice, Inbred DBA; D013154:Spleen / Q000166:cytology
chemical_list: D000939:Epitopes