title: Comparison of T cell receptor alpha, beta, and gamma gene rearrangement and expression in T cell acute lymphoblastic leukemia.
abstract: We have analyzed the configuration of the T cell receptor (TCR) alpha gene using newly developed genomic joining region (J alpha) probes, which cover approximately 80 kb of the J alpha region upstream from the constant region in 19 patients with T cell acute lymphoblastic leukemia (T-ALL) and in three CD3- leukemic T cell lines (HSB2, CEM, and MOLT4). In parallel, transcription of the TCR-alpha, beta, and gamma genes was examined in 11 of these patients and in the T cell lines. All T-ALL and the three T cell lines exhibited both TCR-gamma and beta gene rearrangements. 8 of 10 T-ALL and all T cell lines expressed TCR-gamma transcripts. All samples tested expressed both TCR-beta and CD3-gamma transcripts. TCR alpha transcripts were only observed in CD3+ T-ALL but not in CD3- T-ALL or the CD3- cell lines. Among the CD3+ T-ALL, eight had TCR-alpha gene rearrangements. In addition, TCR-alpha gene rearrangements were detected in one CD3- T-ALL and all three T cell lines. These leukemic cells may represent a transient stage between rearrangement and expression and provide an opportunity for analyzing the mechanism regulating the expression of the TCR-alpha gene.
authors.affiliation: Division of Immunology and Rheumatology, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Hara
authors.forename: S H
authors.initials: SH
authors.lastname: Benedict
authors.forename: E
authors.initials: E
authors.lastname: Champagne
authors.forename: T W
authors.initials: TW
authors.lastname: Mak
authors.forename: M
authors.initials: M
authors.lastname: Minden
authors.forename: E W
authors.initials: EW
authors.lastname: Gelfand
mesh_terms: D004273:DNA, Neoplasm / Q000235:genetics; D005786:Gene Expression Regulation; D005796:Genes; D006801:Humans; D007945:Leukemia, Lymphoid / Q000235:genetics*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D011948:Receptors, Antigen, T-Cell