Tumor bearer T cells suppress Bacillus Calmette-Guérin-potentiated antitumor responses. III. Identification of an auxiliary efferent suppressor-T-cell population.
T cells (Ts-eff) induced in BALB/c mice by subcutaneous (sc) growth of syngeneic Meth A tumors can adoptively suppress the effector phase of delayed-type hypersensitivity (DTH) in Bacillus Calmette-Guérin (BCG)-primed and unprimed recipients which have been sensitized with irradiated Meth A cells but they do not inhibit the augmented DTH response in recipients inoculated with cyclophosphamide (CY) 2 days prior to sensitization. By reconstituting CY-treated immunized recipients with selected spleen cell populations, it has been demonstrated that Ts-eff suppress DTH by interacting with a second or auxiliary suppressor cell population present in immune but not normal spleens. These auxiliary suppressor cells (Ts-aux) are Thy+, Lyt 1-2+ and I-J+, phenotypically similar to Ts-eff. Their activity is not influenced by B-cell depletion. Unlike Ts-eff, Ts-aux do not bear receptors specific for Meth A cells. Ts-aux and Ts-eff share similar sensitivity to irradiation and high dose (100 mg/kg) CY but unlike Ts-eff, Ts-aux are cortisone sensitive, nondividing, nonadherent cells which are absent from the thymus. The phenotype and mechanism of action of Ts-aux resemble those of the auxiliary or Ts3 cells defined in models of contact sensitivity, DTH to simple haptens, and in vitro antibody responses.
D000818:Animals; D000950:Antigens, Ly / Q000032:analysis; D001500:BCG Vaccine / Q000276:immunology; D003348:Cortisone / Q000494:pharmacology; D003520:Cyclophosphamide / Q000494:pharmacology; D005260:Female; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D007108:Immune Tolerance / Q000187:drug effects; D007111:Immunity, Cellular / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000276:immunology; D009374:Neoplasms, Experimental / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000145:classification / Q000276:immunology*
D000950:Antigens, Ly; D001500:BCG Vaccine; D003520:Cyclophosphamide; D003348:Cortisone