title: T-cell repertoire in a strain of transgenic C57BL/6 mice with the HLA-DRA gene on the X-chromosome.
abstract: We have established a strain of transgenic mice in which the HLA-DRA gene was integrated into the X-chromosome and the xenogeneic mixed isotype molecule, DR alpha E beta b, was expressed in a cell type-specific manner, although the transgenic DRA gene contained only 268 base pairs of the 5'-flanking region. The DR alpha E beta b molecules expressed in the transgenic mice functioned as major histocompatibility complex (MHC) class II to select T-cell repertoire, and to stimulate mixed lymphocyte reaction. In female transgenic mice homozygous for HLA-DRA (DR alpha-B6-F-homo) and male transgenic mice (DR alpha-B6-M), DR alpha E beta b molecules were expressed in almost all of the MHC class II Ab-positive cells. In contrast, the expression of DR alpha E beta b molecules in female transgenic mice hemizygous for HLA-DRA (DR alpha-B6-F-hemi) was found only in part of the Ab positive cells, and the proportion of cells expressing the DR alpha E beta b molecules varied due to random inactivation of one of the X-chromosomes. Clonal deletions of the T cells and mature thymocytes bearing Tcrb-V5 and Tcrb-V11, which are eliminated from the peripheral repertoire in mice expressing self-superantigen and MHC class II E molecules, were incomplete in DR alpha-B6-F-hemi as compared with those in DR alpha-B6-F-homo, and were correlated with the proportion of DR alpha E beta b-positive spleen cells. These observations suggested that the number of bone marrow-derived cells expressing DR alpha E beta b molecules was critical for clonal deletions of Tcrb-V5+ and Tcrb-V11+ T cells in the thymus.
authors.affiliation: Department of Genetics, Kyushu University, Fukuoka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Fukui
authors.forename: Y
authors.initials: Y
authors.lastname: Esaki
authors.forename: A
authors.initials: A
authors.lastname: Kimura
authors.forename: K
authors.initials: K
authors.lastname: Hirokawa
authors.forename: Y
authors.initials: Y
authors.lastname: Nishimura
authors.forename: T
authors.initials: T
authors.lastname: Sasazuki
mesh_terms: D000818:Animals; D005260:Female; D008040:Genetic Linkage; D006683:HLA-DQ Antigens / Q000502:physiology; D006684:HLA-DR Antigens / Q000235:genetics*; D059805:HLA-DR alpha-Chains; D007108:Immune Tolerance; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology*; D014960:X Chromosome
chemical_list: D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D059805:HLA-DR alpha-Chains; D016693:Receptors, Antigen, T-Cell, alpha-beta