title: Contrasuppression and tumor rejection.
abstract: The growth of a highly progressive MCA-induced tumor 3152-PRO is dependent on the activity of suppressor T cells (Ts). Injection of syngeneic mice with antibodies specific for Ts leads to enhanced tumor transplantation resistance of the 3152-PRO tumor. In addition, injection of recipient mice with highly immunogenic regressor tumors conjugated with trinitrophenyl (TNP) activates a T cell population which also mediates protection to transplantation of TNP-conjugated 3152-PRO tumor cells. One such tumor, 1591-RE, was investigated in detail to determine the phenotype and biologic activity of this T cell population in overcoming Ts cell activity. Induction of transplantation resistance requires the presence of TNP hapten on both the highly regressive immunizing tumor (and not its progressor variant 1591-PRO4), and on the challenge tumor 3152-PRO. The cell population from TNP-1591-RE immunized animals which mediates protection against the transplantation of TNP-3152-PRO is Thy-1+, CD4+, 8-, Lyt1+, I-J+, and Vicia villosa lectin adherent, the identical phenotype to antigen-specific contrasuppressor T cells in the contact sensitivity (CS) response to TNP in vivo. A T cell population of identical phenotype from TNP-1591-RE immunized mice can overcome the effects of antigen-specific Ts cells on PCl-immune cells in the adoptive transfer of CS in vivo. These results suggest that immunoregulatory cells that mediate protection against progressive tumors may be identical in function to antigen-specific contrasuppressor T cells.
mesh_terms: D000818:Animals; D006084:Graft Rejection; D006241:Haptens / Q000276:immunology; D007116:Immunization, Passive; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D014185:Transplantation, Isogeneic; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D006241:Haptens; D014301:Trinitrobenzenes