Structure of the two promoters of the human lck gene: differential accumulation of two classes of lck transcripts in T cells

1989 ◽  
Vol 9 (5) ◽  
pp. 2173-2180
Author(s):  
T Takadera ◽  
S Leung ◽  
A Gernone ◽  
Y Koga ◽  
Y Takihara ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Carcinoma Cell ◽  
Human Peripheral Blood ◽  
Specific Gene ◽  
Type I ◽  
Type Ii ◽  
Carcinoma Cell Lines ◽  
Human T Cell

The human T-cell- or lymphocyte-specific gene, lck, encodes a tyrosine kinase and is a member of the src family. In this report we demonstrate that there are two classes of human lck transcripts (types I and II), containing different 5'-untranslated regions, which are expressed from two distinct promoters. No apparent sequence similarity was observed between the 5'-flanking regions of the two promoters. The expression of lck in human T-cell leukemia and carcinoma cell lines and in human peripheral blood T lymphocytes was examined by S1 nuclease and primer extension mapping and by Northern (RNA) blot analysis of total cellular RNA. The following results were obtained. (i) Two RNA start sites in the downstream promoter were used to generate type I transcripts. (ii) The major human type I start site has not been described for the mouse. (iii) At least five RNA start sites in the upstream promoter were used to generate type II transcripts. (iv) In T cells and in two colon carcinoma cell lines, type II transcripts were present in higher amounts than type I transcripts. (v) In T cells treated with phytohemagglutinin, tetradecanoylphorbol acetate, and cyclosporin A, the modulation of lck expression was associated primarily with changes in levels of type II transcripts. The above results suggest that the two human lck promoters are utilized differentially and may be regulated independently during certain physiological states.

scholarly journals Structure of the two promoters of the human lck gene: differential accumulation of two classes of lck transcripts in T cells.

1989 ◽  
Vol 9 (5) ◽  
pp. 2173-2180 ◽  
Author(s):  
T Takadera ◽  
S Leung ◽  
A Gernone ◽  
Y Koga ◽  
Y Takihara ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Carcinoma Cell ◽  
Human Peripheral Blood ◽  
Specific Gene ◽  
Type I ◽  
Type Ii ◽  
Carcinoma Cell Lines ◽  
Human T Cell

The human T-cell- or lymphocyte-specific gene, lck, encodes a tyrosine kinase and is a member of the src family. In this report we demonstrate that there are two classes of human lck transcripts (types I and II), containing different 5'-untranslated regions, which are expressed from two distinct promoters. No apparent sequence similarity was observed between the 5'-flanking regions of the two promoters. The expression of lck in human T-cell leukemia and carcinoma cell lines and in human peripheral blood T lymphocytes was examined by S1 nuclease and primer extension mapping and by Northern (RNA) blot analysis of total cellular RNA. The following results were obtained. (i) Two RNA start sites in the downstream promoter were used to generate type I transcripts. (ii) The major human type I start site has not been described for the mouse. (iii) At least five RNA start sites in the upstream promoter were used to generate type II transcripts. (iv) In T cells and in two colon carcinoma cell lines, type II transcripts were present in higher amounts than type I transcripts. (v) In T cells treated with phytohemagglutinin, tetradecanoylphorbol acetate, and cyclosporin A, the modulation of lck expression was associated primarily with changes in levels of type II transcripts. The above results suggest that the two human lck promoters are utilized differentially and may be regulated independently during certain physiological states.

scholarly journals Mother-to-offspring transmission of human T cell leukemia virus type I in rabbits

Blood ◽  
1987 ◽  
Vol 69 (4) ◽  
pp. 1255-1258 ◽  
Author(s):  
Y Uemura ◽  
S Kotani ◽  
S Yoshimoto ◽  
M Fujishita ◽  
M Yamashita ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Virus Type ◽  
Leukemia Virus ◽  
Type I ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Leukemia Virus

Abstract We studied the mode of natural transmission of human T-cell leukemia virus type I (HTLV-I) in rabbits. Four virus-infected rabbits (2 males and 2 females) were individually mated with 4 noninfected rabbits. Two virus-infected females mated with noninfected males gave birth to 7 offspring, and 2 noninfected females mated with infected males delivered 5 offspring. Four of the seven offspring born to the virus- infected mothers seroconverted for HTLV-I when aged 6 to 13 weeks with antibody titers of 1:40 to 1:160. None of the five offspring born to the noninfected mothers became seropositive during the observation period of 6 months, however. Peripheral lymphocytes were cultured with T cell growth factor, and HTLV-I-carrying lymphoid cell lines were established from the four seroconverted rabbits. All four cell lines were of T cells positive for Ia antigens. In addition, none of five newborn rabbits killed immediately after birth to a virus-infected rabbit was infected with HTLV-I. These findings provide an experimental support for the milkborne transmission of HTLV-I from mother to child in humans and indicate that the virus is tropic for T cells in rabbits as well.

scholarly journals Human mature T cells that are anergic in vivo prevail in SCID mice reconstituted with human peripheral blood.

1992 ◽  
Vol 175 (2) ◽  
pp. 503-516 ◽  
Author(s):  
M Tary-Lehmann ◽  
A Saxon
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Critical Role ◽  
Scid Mice ◽  
Human T Cell ◽  
Human T Cells ◽  
T Cell Lines

In these studies we have characterized the human cells that repopulate severe combined immunodeficient (SCID) mice after injection of adult peripheral blood or cord blood (hu-PBL-SCID mice). In all organs of the chimeras, and at any time point tested, single-positive (CD4+ or CD8+) T cells that expressed the alpha/beta T cell receptor (TCR) prevailed. All T cells were CD45RO+ and the majority were also HLA-DR+. Thus, the human T cells in the chimeras exhibited the phenotype of mature, memory cells that showed signs of recent activation. Cell cycle studies revealed a mitotically active human T cell population in the murine host. However, when freshly isolated from the chimeras, the human T cells were refractory to stimulation by anti-CD3 antibody but proliferated in response to exogenous interleukin 2. Chimera-derived human T cell lines retained this state of unresponsiveness to TCR-triggered proliferation for 4-6 wk in vitro. Subsequently, the T cell lines developed responses to anti-CD3 stimulation and 9 of 11 of the lines also proliferated in response to splenic stimulator cells of SCID mice. These data demonstrate that the human T cells are in a state of reversible anergy in the murine host and that xenoreactivity might play a critical role in hu-PBL-SCID mice. Mechanisms that may determine repopulation of SCID mice with human peripheral blood mononuclear cells are discussed.

scholarly journals Mother-to-offspring transmission of human T cell leukemia virus type I in rabbits

Blood ◽  
1987 ◽  
Vol 69 (4) ◽  
pp. 1255-1258
Author(s):  
Y Uemura ◽  
S Kotani ◽  
S Yoshimoto ◽  
M Fujishita ◽  
M Yamashita ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Lines ◽  
Virus Type ◽  
Leukemia Virus ◽  
Type I ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Leukemia Virus

We studied the mode of natural transmission of human T-cell leukemia virus type I (HTLV-I) in rabbits. Four virus-infected rabbits (2 males and 2 females) were individually mated with 4 noninfected rabbits. Two virus-infected females mated with noninfected males gave birth to 7 offspring, and 2 noninfected females mated with infected males delivered 5 offspring. Four of the seven offspring born to the virus- infected mothers seroconverted for HTLV-I when aged 6 to 13 weeks with antibody titers of 1:40 to 1:160. None of the five offspring born to the noninfected mothers became seropositive during the observation period of 6 months, however. Peripheral lymphocytes were cultured with T cell growth factor, and HTLV-I-carrying lymphoid cell lines were established from the four seroconverted rabbits. All four cell lines were of T cells positive for Ia antigens. In addition, none of five newborn rabbits killed immediately after birth to a virus-infected rabbit was infected with HTLV-I. These findings provide an experimental support for the milkborne transmission of HTLV-I from mother to child in humans and indicate that the virus is tropic for T cells in rabbits as well.

Synthesis of 6-Azapurines by Transformation of Toxoflavins and Reumycins (7-Azapteridines) and their Cytotoxicities

2015 ◽  
Vol 68 (2) ◽  
pp. 203 ◽  
Author(s):  
Jun Ma ◽  
Fumio Yoneda ◽  
Tomohisa Nagamatsu
Keyword(s):  
T Cell ◽  
Sodium Hydroxide ◽  
Cell Lines ◽  
Carcinoma Cell ◽  
Facile Synthesis ◽  
Carcinoma Cell Lines ◽  
Human T Cell ◽  
Acid Type ◽  
Benzilic Acid

This paper describes a reliable and facile synthesis of 6-azapurines, 1,5-dimethyl-1H-imidazo[4,5-e][1,2,4]triazin-6(5H)-ones and 5-methyl-5H-imidazo[4,5-e][1,2,4]triazin-6(7H)-ones, by treatment of toxoflavins and reumycins with 10 % aqueous or ethanolic sodium hydroxide at 5–70°C or reflux, followed by decarboxylation and oxidation by air along with a benzilic acid type rearrangement. Furthermore, heating the produced 6-azapurines in 10 % ethanolic sodium hydroxide afforded the corresponding 1-methyl-5,6-dioxo-1,4,5,6-tetrahydro-1,2,4-triazines with 1-methylurea. The antitumour activities of the 6-azapurines against CCRF-HSB-2 (human T-cell acute lymphoblastoid leukemia) and KB (human oral epidermoid carcinoma) cell lines were also investigated in vitro and some of the compounds showed prospective antitumour activities.

scholarly journals Activation of T cell-derived lymphokine genes in T cells and fibroblasts: effects of human T cell leukemia virus type I p40xprotein and bovine papilloma virus encoded E2 protein

1988 ◽  
Vol 16 (14) ◽  
pp. 6547-6566 ◽  
Author(s):  
Shoichiro Miyatake ◽  
Motoharu Seiki ◽  
Rene DeWaal Malefijt ◽  
Toshio Heike ◽  
Jun-ichi Fujisawa ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Virus Type ◽  
Leukemia Virus ◽  
Type I ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Papilloma Virus ◽  
Human T Cell ◽  
T Cell Leukemia Virus

Protective effect of interferon ? on human T cell leukaemia virus type I infection of CD4+ T cells isolated from human cord blood

1993 ◽  
Vol 37 (2) ◽  
pp. 97-104 ◽  
Author(s):  
Beatrice Macchi ◽  
Isabella Faraoni ◽  
Antonio Mastino ◽  
Chiara D'Onofrio ◽  
Gianna Romeo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Protective Effect ◽  
Cord Blood ◽  
Virus Type ◽  
Cell Leukaemia ◽  
Type I ◽  
Human Cord Blood ◽  
Leukaemia Virus ◽  
Human T Cell

scholarly journals Cytokine Expression and Tumorigenicity of Large Granular Lymphocytic Leukemia Cells From Mice Transgenic for the tax Gene of Human T-Cell Leukemia Virus Type I

Blood ◽  
1997 ◽  
Vol 90 (2) ◽  
pp. 783-794 ◽  
Author(s):  
William J. Grossman ◽  
Lee Ratner
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Transgenic Animal ◽  
Type I ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Gm Csf ◽  
Human T Cell ◽  
T Cell Leukemia Virus

The human T-cell leukemia virus type I (HTLV-I) regulatory protein, Tax, has been speculated to play a major role in HTLV-I leukemogenesis. Indeed, several studies have suggested that upregulation of various cellular oncogenes and cytokines by Tax may explain the pathogenesis observed in HTLV-I–infected individuals, as well as several Tax-transgenic animal models. We report here the analysis of cytokine expression in a Tax-transgenic animal model with large granular lymphocytic (LGL) leukemia. Two different transgenic mice showed identical expression of interleukin-1α (IL-1α), IL-1β, interferon γ (IFNγ), and granulocyte-macrophage colony-stimulating factor (GM-CSF ) in peripheral tail tumors. Interestingly, LGL cell lines derived from these same tumors expressed high levels of both IFNγ and GM-CSF, which correlated with the level of Tax expression. These same LGL cell lines also expressed high levels of lymphocyte function-associated antigen-1 (LFA-1) and intracellular adhesion molecule-1 (ICAM-1). Engraftment of these LGL cell lines into severe combined immunodeficient (SCID) mice led to the development of leukemia and lymphomas. Examination of these SCID mice showed that their pathology was nearly identical to that observed in the original Tax-transgenic mouse model. Both the Tax-transgenic and engrafted SCID mouse models allow for the analysis of cellular events that are required for tumor development associated with HTLV infection and suggest that Tax expression may be responsible for the upregulation of certain cytokines and adhesion molecules that affect the infiltrating capabilities of HTLV-I–infected cells.

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