title: Lower receptor avidity required for thymic clonal deletion than for effector T-cell function.
abstract: Clonal deletion in the thymus plays a major part in T-cell tolerance to self antigens. But the mechanism of negative selection, its fine specificity and the threshold of affinity and avidity remains unknown. We have now examined these aspects of negative selection with mice expressing a transgenic T-cell receptor with specificity for lymphocytic choriomeningitis virus (LCMV) glycoprotein in association with the class I H-2Db molecule. These mice were rendered tolerant to LCMV by neonatal infection with mutant LCMVs bearing point mutations in the T-cell epitope recognized by the transgenic T-cell receptor. Variant LCMVs were also tested for their ability to elicit antiviral responses in transgenic mice in vivo and in vitro. Comparison in vivo revealed that a low-avidity receptor interaction, which was unable to induce effector T cells in the periphery, was still sufficient for clonal deletion in the thymus.
authors.affiliation: Institute of Pathology, University Hospital, Zurich, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Pircher
authors.forename: U H
authors.initials: UH
authors.lastname: Rohrer
authors.forename: D
authors.initials: D
authors.lastname: Moskophidis
authors.forename: R M
authors.initials: RM
authors.lastname: Zinkernagel
authors.forename: H
authors.initials: H
authors.lastname: Hengartner
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D001483:Base Sequence; D000939:Epitopes / Q000276:immunology; D007108:Immune Tolerance; D008217:Lymphocytic choriomeningitis virus / Q000235:genetics / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009154:Mutation; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D000939:Epitopes; D011948:Receptors, Antigen, T-Cell