title: Role of the complementarity-determining region 3 (CDR3) of the TCR-beta chains associated with the V alpha 14 semi-invariant TCR alpha-chain in the selection of CD4+ NK T Cells.
abstract: The NK1.1(+)TCRalphabeta(int) CD4(+), or double negative T cells (NK T cells) consist of a mixture of CD1d-restricted and CD1d-unrestricted cells. The relationships between CD4(+)NK1.1(+) T cells and conventional T cells are not understood. To compare their respective TCR repertoires, NK1.1(+)TCRalphabeta(int), CD4(+) T cells have been sorted out of the thymus, liver, spleen, and bone marrow of C57BL/6 mice. Molecular analysis showed that thymus and liver used predominantly the Valpha14-Jalpha281 and Vbeta 2, 7, and 8 segments. These cells are CD1d restricted and obey the original definition of NK T cells. The complementarity-determining region 3 (CDR3) sequences of the TCR Vbeta8.2-Jbeta2.5 chain of liver and thymus CD4(+) NK T cells were determined and compared with those of the same rearrangements of conventional CD4(+) T cells. No amino acid sequence or usage characteristic of NK T cells could be evidenced: the Vbeta8.2-Jbeta2.5 diversity regions being primarily the same in NK T and in T cells. No clonal expansion of the beta-chains was observed in thymus and liver CD1d-restricted CD4(+)NK T cells, suggesting the absence of acute or chronic Ag-driven stimulation. Molecular analysis of the TCR used by Valpha14-Jalpha281 transgenic mice on a Calpha(-/-) background showed that the alpha-chain can associate with beta-chains using any Vbeta segment, except in NK T cells in which it paired predominately with Vbeta 2, 7, and 8(+) beta-chains. The structure of the TCR of NK T cells thus reflects the affinity for the CD1d molecule rather than a structural constraint leading to the association of the invariant alpha-chain with a distinctive subset of Vbeta segment.
authors.affiliation: Unité de Biologie Moléculaire du Gène, Département d'Immunologie, Institut Pasteur, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Ronet
authors.forename: M
authors.initials: M
authors.lastname: Mempel
authors.forename: N
authors.initials: N
authors.lastname: Thieblemont
authors.forename: A
authors.initials: A
authors.lastname: Lehuen
authors.forename: P
authors.initials: P
authors.lastname: Kourilsky
authors.forename: G
authors.initials: G
authors.lastname: Gachelin
mesh_terms: D000818:Animals; D000941:Antigens / Q000096:biosynthesis; D000950:Antigens, Ly; D000954:Antigens, Surface; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism; D015704:CD4 Antigens / Q000096:biosynthesis*; D002469:Cell Separation; D002999:Clone Cells; D005786:Gene Expression Regulation / Q000276:immunology; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor / Q000276:immunology; D019673:Genes, T-Cell Receptor alpha / Q000276:immunology; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D037181:Lectins, C-Type; D008099:Liver / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D055651:NK Cell Lectin-Like Receptor Subfamily B; D009928:Organ Specificity / Q000276:immunology; D014176:Protein Biosynthesis; D011506:Proteins; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology / Q000378:metabolism
chemical_list: D000941:Antigens; D000950:Antigens, Ly; D000954:Antigens, Surface; D015704:CD4 Antigens; C527211:Klrb1c protein, mouse; D037181:Lectins, C-Type; D055651:NK Cell Lectin-Like Receptor Subfamily B; D011506:Proteins; D016693:Receptors, Antigen, T-Cell, alpha-beta