title: Mechanism of action of a T suppressor factor (TsF) in contact sensitivity: the T cell target for TsF activity in adoptive transfer of immunity is not effector cell.
abstract: The passive transfer of contact sensitivity (CS) by immune cells into normal animals requires the interaction of two distinct Ly-1+ T cells, one which is Vicia villosa lectin (VV)-nonadherent, the other which adheres to VV. Functional deletion of either cell type abrogates the adoptive transfer of CS into normal animals, whereas VV-nonadherent cells alone can transfer CS into animals pretreated with cyclophosphamide (Cy). An antigen-specific T suppressor factor, designated TNP-TsF, inhibits the transfer of CS into normal adoptive recipients. TNP-TsF mediates its suppressive activity by inducing an I-J+ subfactor (designated I-J2) from the assay population by the interaction of PC1-F (a TNP-binding subfactor of TNP-TsF) with antigen-primed Ly-2+ T cells. This I-J+ subfactor then complements TNBS-F (an antigen-nonbinding subfactor of TNP-TsF) to form an antigen-nonspecific effector molecule which suppresses DTH responses in an antigen-nonspecific fashion. We report here that TNP-TsF suppresses the adoptive transfer of CS into normal animals but not into animals pretreated with Cy. TNBS-F + I-J2, the effector complex of TNP-TsF, also suppresses the transfer of CS into normal but not Cy-treated animals. When the Ly-1 immune cells were separated into VV-adherent and -nonadherent populations, the TNBS-F + I-J2 suppressor complex suppressed the functional activity of the VV-adherent cell population, but not the VV-nonadherent cells. This suppressive activity correlates with the need for VV-adherent cells in the transfer of CS into normal but not Cy-treated recipients. When an I-J+ molecule (I-J1) from an SRBC-specific TsF was used in place of I-J2 to form a suppressor complex with TNBS-F, this TNBS-F + I-J1 TsF suppressed the transfer of CS into both normal and Cy-treated recipients. This difference in functional suppressive activity correlated with a difference in target cell specificity: TNBS-F + I-J1 suppressed the VV-nonadherent TDTH cell, whereas TNBS-F + I-J2 suppressed the VV-adherent T cell of CS. Immune cells which are transferred under conditions which do not require the VV-adherent cell for transfer are not suppressed by TNBS-F + I-J2 or TNP-TsF, but are suppressed by the TNBS-F + I-J1.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis; D003877:Dermatitis, Contact / Q000276:immunology*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007108:Immune Tolerance; D007111:Immunity, Cellular; D007116:Immunization, Passive; D037102:Lectins; D051379:Mice; D010853:Picryl Chloride / Q000276:immunology; D037121:Plant Lectins; D013491:Suppressor Factors, Immunologic / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D014302:Trinitrobenzenesulfonic Acid / Q000276:immunology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D037102:Lectins; D037121:Plant Lectins; D013491:Suppressor Factors, Immunologic; C042242:Vicia lectins; D014302:Trinitrobenzenesulfonic Acid; D010853:Picryl Chloride