title: Diversity and structure of human T cell receptor delta chain genes in peripheral blood gamma/delta-bearing T lymphocytes.
abstract: We have investigated the diversity and repertoire of human TCR delta chain variable gene segments in the human peripheral blood CD4- CD8- (double-negative) population, using rearrangement and expression studies and sequence analyses. 20 TCR delta DNA clones were derived from the RNA of bulk-cultured double-negative T cells and their nucleotide sequences determined. These clones can be classified into six different V delta subfamilies. The distribution, however, was uneven in these cells, with 16 of 20 being derived from the V delta 1 (9) and V delta 2 (7) subfamilies. The remaining subfamilies, V delta 3, V delta 4, V delta 5, and V delta 6, were only represented by one clone each. The majority of these subfamilies seem to consist of a single member, in contrast with the closely linked V alpha subfamilies, which, in most cases, consist of multiple members. Our findings suggest that only a limited number of V delta genes are used in human peripheral blood double-negative T cells and that two major V delta subfamilies (V delta 1 and V delta 2) are used more frequently. Sequence comparison of our cDNA clones to V alpha clones indicates that there is no overlap in usage of V alpha and V delta gene segments, except for the V delta 4 (V alpha 6) subfamily. Comparison of the different V delta sequences suggests that the majority of the sequence diversity is concentrated in the junctions between V, D, and J segments and results from extensive N region diversity.
authors.affiliation: Department of Medical Biophysics and Immunology, University of Toronto, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Takihara
authors.forename: J
authors.initials: J
authors.lastname: Reimann
authors.forename: E
authors.initials: E
authors.lastname: Michalopoulos
authors.forename: E
authors.initials: E
authors.lastname: Ciccone
authors.forename: L
authors.initials: L
authors.lastname: Moretta
authors.forename: T W
authors.initials: TW
authors.lastname: Mak
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002999:Clone Cells; D005796:Genes; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000032:analysis* / Q000235:genetics*; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000502:physiology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta