title: Cell-mediated suppression of tumor immunity has a non-specific component. I. Evidence from transplantation tests.
abstract: We have first demonstrated that the growth of a transplanted, 3-methyl-cholanthrene-induced BALB/c sarcoma, MCA-1425, in specifically immune syngeneic mice, was facilitated when the MCA-1425 tumor cells were injected together with either a mixture of irradiated MCA-1425 cells and thymus cells from mice immune to MCA-1425 or a mixture of irradiated cells from an antigenically different BALB/c sarcoma, MCA-1460, and thymus cells from mice immune to MCA-1460. We then performed Winn assays to study the induction of an immune response that could prevent the outgrowth of MCA-1425 cells in irradiated syngeneic recipients. Tumor immunity was found to be suppressed, if the mice immunized by a subcutaneous transplant of MCA-1425 cells and used as lymphocyte donors, were injected intraperitoneally with cells from either a different sarcoma, MCA-1460, or from 12-day BALB/c embryos. We tentatively attribute our finding to antigen-non-specific suppressor effector cells and postulate that an antigen-specific event is often involved in their induction.
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm; D000939:Epitopes; D005260:Female; D005354:Fibrosarcoma / Q000139:chemically induced / Q000276:immunology; D008297:Male; D008748:Methylcholanthrene; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D012513:Sarcoma, Experimental / Q000139:chemically induced / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000951:Antigens, Neoplasm; D000939:Epitopes; D008748:Methylcholanthrene