title: Identification of a new type of invariant V alpha 14+ T cells and responsiveness to a superantigen, Yersinia pseudotuberculosis-derived mitogen.
abstract: We examined the expression of the H4 T cell activation marker in thymic T cell subpopulations and found that TCR-alpha beta+ CD4+ thymic T cells are segregated into three subpopulations based upon H4 levels. Thymic T cells with either no or low H4 expression differentiate via the mainstream differentiation pathway in the thymus. H4int thymic T cells, which express a skewed V beta repertoire of V beta 2, -7, and -8 in their TCRs, show the phenotype of NKT cells: CD44high, Ly6Chigh, NK1.1+, and TCR-alpha beta low. H4high thymic T cells also show a skewed V beta repertoire, V beta 2, -7, and -8, and predominantly express an invariant V alpha 14-J alpha 281+ alpha-chain in their TCRs but constitute a distinct population in that they are CD44int, Ly6C-, NK1.1-, and TCR-alpha beta high. Thus, invariant V alpha 14+ thymic T cells consist of ordinary NKT cells and a new type of T cell population. V beta 7+ and V beta 8.1+ invariant V alpha 14+ thymic T cells are present in DBA/2 mice, which carry mammary tumor virus-7-encoded superantigens, in comparable levels to those in BALB/c mice. Furthermore, V beta 7+ invariant V alpha 14+ thymic T cells in DBA/2 mice are in the immunologically responsive state, and Yersinia pseudotuberculosis-derived mitogen-induced V beta 7+ invariant V alpha 14+ thymic T cell blasts from DBA/2 and BALB/c mice exhibited equally enhanced responses upon restimulation with Y. pseudotuberculosis-derived mitogen. Thus, invariant V alpha 14+ thymic T cells that escape negative selection in DBA/2 mice contain T cells as functionally mature as those in BALB/c mice.
authors.affiliation: Department of Microbiology and Immunology, Institute of Laboratory Animals, Tokyo Women's Medical University, Japan. jyagi1@research.twmu.ac.jp
authors.forename: J
authors.initials: J
authors.lastname: Yagi
authors.forename: U
authors.initials: U
authors.lastname: Dianzani
authors.forename: H
authors.initials: H
authors.lastname: Kato
authors.forename: T
authors.initials: T
authors.lastname: Okamoto
authors.forename: T
authors.initials: T
authors.lastname: Katsurada
authors.forename: D
authors.initials: D
authors.lastname: Buonfiglio
authors.forename: T
authors.initials: T
authors.lastname: Miyoshi-Akiyama
authors.forename: T
authors.initials: T
authors.lastname: Uchiyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000096:biosynthesis; D001426:Bacterial Proteins / Q000276:immunology*; D015704:CD4 Antigens / Q000096:biosynthesis; D002454:Cell Differentiation / Q000187:drug effects / Q000276:immunology; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D015778:Minor Histocompatibility Antigens / Q000096:biosynthesis; D008934:Mitogens / Q000276:immunology*; D008969:Molecular Sequence Data; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis*; D018089:Superantigens / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism* / Q000382:microbiology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015011:Yersinia pseudotuberculosis / Q000276:immunology*
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; D001426:Bacterial Proteins; D015704:CD4 Antigens; D000949:Histocompatibility Antigens Class II; D015778:Minor Histocompatibility Antigens; D008934:Mitogens; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; C093313:Yersinia pseudotuberculosis-derived mitogen; C045084:invariant chain; D003907:Dexamethasone