title: Effect of adult thymectomy on tumour immunity in mice.
abstract: The effect of adult thymectomy in DBA/2J mice on the in vitro response to syngeneic tumour cells was investigated. Spleen cells from adult mice which had been thymectomized 8 weeks previously demonstrated a severely impaired primary cytotoxic response to P815 tumour cells, whereas their cytotoxic responses to allogeneic cells (C57BL/6) and to non-H-2 antigens (BALB/c), and their ability to form a primary antibody response to sheep red blood cells was unimpaired. Suppressor T cells, specific for P815 cells, appeared early in the thymuses of animals inoculated with P815 cells (between 4 and 8 days after tumour-cell injection). No differences in tumour growth between animals thymectomized as adults and sham-operated controls were observed, and thymectomized tumour-bearing animals had levels of specific suppressor cells in their lymph nodes equivalent to the levels found in untreated controls. Severely thymocyte-deprived animals which had been thymectomized, irradiated and reconstituted with either marrow or spleen cells 8 weeks before tumour implantation succumbed more rapidly to metastatic tumour than did control animals.
mesh_terms: D000818:Animals; D003602:Cytotoxicity, Immunologic; D005260:Female; D007165:Immunosuppression Therapy; D066298:In Vitro Techniques; D008212:Lymphocyte Depletion; D051379:Mice; D008815:Mice, Inbred Strains; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D013934:Thymectomy; D013997:Time Factors; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic