title: Tumor-specific T helper activity can be abrogated by two distinct suppressor cell mechanisms.
abstract: Tumor-specific helper T cell activity was detected in the spleens of tumor-bearing mice using a sensitive, simple and reproducible in vitro assay based on those previously described for soluble hapten-carrier antigens. Helper activity disappears when the tumor is large. This is coincident with the appearance of two distinct types of suppressor cells: (a) T cells which suppress tumor-specific T helper responses and (b) non-T cells which are nonspecific in their action.
mesh_terms: D000818:Animals; D005260:Female; D051379:Mice; D008809:Mice, Inbred C3H / Q000276:immunology; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D013154:Spleen / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D013997:Time Factors