title: Positive selection of T-lymphocytes induced by intrathymic injection of a thymic epithelial cell line.
abstract: T lymphocytes recognize antigens as peptide fragments associated with molecules encoded by the major histocompatibility complex (MHC) and expressed on the surface of antigen-presenting cells. In the thymus, T cells bearing alpha beta receptors that react with the MHC molecules expressed by radioresistant stromal elements are positively selected for maturation. In (A x B-->A) bone marrow chimaeras, T cells restricted to the MHC-A haplotype are positively selected, whereas MHC-B-reactive thymocytes are not. We investigated whether the introduction of particular thymic stromal elements bearing MHC-B molecules could alter the fate of B-reactive T cells in these (A x B-->A) chimaeras. Thymic epithelial cell (TEC) lines expressing H-2b were introduced by intrathymic injection into (H-2b/s-->H2s) bone marrow chimaeras and we measured their ability to generate H-2b-restricted cytotoxic T-lymphocytes (CTLs). We report here that one TEC line, 427.1, was able positively to select CTLs specific for influenza and vesicular stomatitis virus antigens in association with class I H-2b molecules. In addition, line 427.1 can process cytoplasmic proteins for presentation to H-2Kb- and H-2Db-restricted CTLs. Thus, a TEC line capable of normal class I MHC antigen processing and presentation in vitro can induce positive selection after intrathymic injection.
authors.affiliation: Department of Immunology, University of Washington, Seattle 98195.
authors.forename: S
authors.initials: S
authors.lastname: Vukmanović
authors.forename: A G
authors.initials: AG
authors.lastname: Grandea
authors.forename: S J
authors.initials: SJ
authors.lastname: Faas
authors.forename: B B
authors.initials: BB
authors.lastname: Knowles
authors.forename: M J
authors.initials: MJ
authors.lastname: Bevan
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D001483:Base Sequence; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000276:immunology*; D007111:Immunity, Cellular; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D009975:Orthomyxoviridae / Q000276:immunology; D011828:Radiation Chimera; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology*; D014407:Tumor Cells, Cultured; D014721:Vesicular stomatitis Indiana virus / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D006183:H-2 Antigens; D009838:Oligodeoxyribonucleotides