title: Tolerance induction in double specific T-cell receptor transgenic mice varies with antigen.
abstract: The crucial role of the thymus in immunological tolerance has been demonstrated by establishing that T cells are positively selected to express a specificity for self major histocompatibility complex (MHC), and that those T cells bearing receptors potentially reactive to self antigen fragments, presumably presented by thymic MHC, are selected against. The precise mechanism by which tolerance is induced and the stage of T-cell development at which it occurs are not known. We have now studied T-cell tolerance in transgenic mice expressing a T-cell receptor with double specificities for lymphocytic choriomeningitis virus (LCMV)-H-2Db and for the mixed-lymphocyte stimulatory (MIsa) antigen. We report that alpha beta TCR transgenic mice tolerant to LCMV have drastically reduced numbers of CD4+CD8+ thymocytes and of peripheral T cells carrying the CD8 antigen. By contrast, tolerance to MIsa antigen in the same alpha beta TCR transgenic MIsa mice leads to deletion of only mature thymocytes and peripheral T cells and does not affect CD4+CD8+ thymocytes. Thus the same transgenic TCR-expressing T cells may be tolerized at different stages of their maturation and at different locations in the thymus depending on the antigen involved.
authors.affiliation: Department of Experimental Pathology, University Hospital, Zurich, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Pircher
authors.forename: K
authors.initials: K
authors.lastname: Bürki
authors.forename: R
authors.initials: R
authors.lastname: Lang
authors.forename: H
authors.initials: H
authors.lastname: Hengartner
authors.forename: R M
authors.initials: RM
authors.lastname: Zinkernagel
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000276:immunology*; D000956:Antigens, Viral / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016827:CD8 Antigens; D003602:Cytotoxicity, Immunologic; D007108:Immune Tolerance; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic / Q000276:immunology*; D016747:Minor Lymphocyte Stimulatory Antigens; D013154:Spleen / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D000956:Antigens, Viral; D016827:CD8 Antigens; D016747:Minor Lymphocyte Stimulatory Antigens