Class II determinants recognized by TNP-specific cloned human T cell lines

Abstract Expression of major histocompatibility complex (MHC) class II molecules in human activated T cells is under normal circumstances regulated exclusively by the CIITA-PIII subtype of the class II transactivator (CIITA). In this study, we show that the absence of MHC class II expression in leukemic T cells was due to a lack of expression of CIITA, whereas in T-lymphoma cells, expression of CIITA correlated with expression of MHC class II. Interestingly, activation of a CIITA-promoter (P)III–reporter construct was not affected in leukemic T cells. This revealed that the absence of endogenous CIITA expression was not caused by a lack of transcription factors critical for CIITA-PIII activation but suggests the involvement of an epigenetic silencing mechanism. Subsequent analysis showed that the lack of human leukocyte antigen–DR (HLA-DR) expression correlated with hypermethylation of CIITA-PIII in leukemic T-cell lines and in primary T-cell acute lymphoblastic leukemia (T-ALL) and a T-cell prolymphocytic leukemia (T-PLL). Treatment of leukemic T-cell lines with a demethylation agent showed re-expression of CIITA-PIII and HLA-DRA. Furthermore, in vitro methylation of CIITA-PIII and subsequent assessment of CIITA-PIII activity in Jurkat leukemic T cells resulted in reduction of constitutive and CREB-1 (cyclic adenosine monophosphate [cAMP]–response element binding protein 1)–induced promoter activity. Together, these results argue for an important role of DNA hyper-methylation in the control of CIITA expression in leukemic T cells.

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Identification of T-cell epitopes on E2 protein of rubella virus, as recognized by human T-cell lines and clones.

Journal of Virology ◽

10.1128/jvi.66.11.6788-6793.1992 ◽

1992 ◽

Vol 66 (11) ◽

pp. 6788-6793 ◽

Cited By ~ 13

Author(s):

D Ou ◽

P Chong ◽

Y Choi ◽

P McVeigh ◽

W A Jefferies ◽

...

Keyword(s):

T Cell ◽

Cell Lines ◽

Rubella Virus ◽

T Cell Epitopes ◽

E2 Protein ◽

Human T Cell ◽

T Cell Lines

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Nonmalignant T cells stimulate growth of T-cell lymphoma cells in the presence of bacterial toxins

Blood ◽

10.1182/blood-2006-04-017863 ◽

2006 ◽

Vol 109 (8) ◽

pp. 3325-3332 ◽

Cited By ~ 38

Author(s):

Anders Woetmann ◽

Paola Lovato ◽

Karsten W. Eriksen ◽

Thorbjørn Krejsgaard ◽

Tord Labuda ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cell Lines ◽

Mhc Class Ii ◽

Interleukin 2 ◽

Class Ii ◽

Bacterial Toxins ◽

Dependent Manner ◽

Malignant Cells ◽

T Cell Lines

AbstractBacterial toxins including staphylococcal enterotoxins (SEs) have been implicated in the pathogenesis of cutaneous T-cell lymphomas (CTCLs). Here, we investigate SE-mediated interactions between nonmalignant T cells and malignant T-cell lines established from skin and blood of CTCL patients. The malignant CTCL cells express MHC class II molecules that are high-affinity receptors for SE. Although treatment with SE has no direct effect on the growth of the malignant CTCL cells, the SE-treated CTCL cells induce vigorous proliferation of the SE-responsive nonmalignant T cells. In turn, the nonmalignant T cells enhance proliferation of the malignant cells in an SE- and MHC class II–dependent manner. Furthermore, SE and, in addition, alloantigen presentation by malignant CTCL cells to irradiated nonmalignant CD4+ T-cell lines also enhance proliferation of the malignant cells. The growth-promoting effect depends on direct cell-cell contact and soluble factors such as interleukin-2. In conclusion, we demonstrate that SE triggers a bidirectional cross talk between nonmalignant T cells and malignant CTCL cells that promotes growth of the malignant cells. This represents a novel mechanism by which infections with SE-producing bacteria may contribute to pathogenesis of CTCL.

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1,25-Dihydroxyvitamin D3 selectively reduces interleukin-2 levels and proliferation of human T cell lines in vitro

Immunology Letters ◽

10.1016/0165-2478(93)90088-j ◽

1993 ◽

Vol 35 (2) ◽

pp. 177-182 ◽

Cited By ~ 62

Author(s):

Klaus Müller ◽

Niels Ødum ◽

Klaus Bendtzen

Keyword(s):

T Cell ◽

Cell Lines ◽

Interleukin 2 ◽

Dihydroxyvitamin D3 ◽

1,25 Dihydroxyvitamin D3 ◽

Human T Cell ◽

T Cell Lines

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Effect of L-Carnitine on Fas-Induced Apoptosis and Sphingomyelinase Activity in Human T Cell Lines

Carnitine Today ◽

10.1007/978-1-4615-6005-0_5 ◽

1997 ◽

pp. 105-117 ◽

Cited By ~ 1

Author(s):

Edoardo Alesse ◽

Luisa Di Marzio ◽

Paola Roncaioli ◽

Francesca Zazzeroni ◽

Adriano Angelucci ◽

...

Keyword(s):

T Cell ◽

Cell Lines ◽

Human T Cell ◽

Induced Apoptosis ◽

T Cell Lines

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Activation of interleukin-13 expression in T cells from HTLV-1-infected individuals and in chronically infected cell lines

Blood ◽

10.1182/blood-2003-04-1043 ◽

2003 ◽

Vol 102 (12) ◽

pp. 4130-4136 ◽

Cited By ~ 27

Author(s):

Hye-Kyung Chung ◽

Howard A. Young ◽

Peter K. C. Goon ◽

Gisela Heidecker ◽

Gerald L. Princler ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Infected Cell ◽

Cell Lines ◽

Regulatory Protein ◽

Immunofluorescent Staining ◽

Cell Leukemia Virus Type ◽

Interleukin 13 ◽

Human T Cell ◽

T Cell Lines

Abstract Human T-cell leukemia virus type 1 (HTLV-1) infection profoundly alters T-cell gene expression, and the dysregulated synthesis of cytokines could influence the course and pathologic consequences of infection. In the process of screening T-cell lines for T helper 1 (Th1) and Th2 cytokine mRNAs, we observed that interleukin-13 (IL-13) mRNA was highly expressed in HTLV-1-infected, IL-2-dependent T-cell lines. IL-9 and interferon gamma (IFN-γ) mRNAs were also expressed at high levels in chronically infected cell lines. IL-5 mRNA was detected in 60% of the HTLV-1-infected cell lines, but mRNAs for IL-4, IL-10, IL-2, and IL-15 were either below detection limits or did not correlate with HTLV-1 infection. Transcriptional activation of the IL-13 promoter by the HTLV-1 Tax trans-regulatory protein was demonstrated in Jurkat T cells transiently transfected with an IL-13 promoter-reporter plasmid. The clinical relevance of these observations was demonstrated by immunofluorescent staining and flow cytometry of lymphocytes obtained from HTLV-1-infected patients. These studies revealed that IL-13 production was directly related to the level of Tax expression in the infected CD4+ T cells soon after in vitro culture. As IL-13 plays key roles in tumor immunosurveillance, asthma, and central nervous system inflammation, it may contribute to the pathophysiology of HTLV-1-associated diseases. (Blood. 2003;102:4130-4136)

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Transcription of HLA class II genes in the absence of B-cell-specific octamer-binding factor.

Molecular and Cellular Biology ◽

10.1128/mcb.8.9.3734 ◽

1988 ◽

Vol 8 (9) ◽

pp. 3734-3739 ◽

Cited By ~ 17

Author(s):

E Stimac ◽

S Lyons ◽

D Pious

Keyword(s):

T Cell ◽

B Cell ◽

Cell Lines ◽

B Lymphocyte ◽

Class Ii ◽

Cell Mutant ◽

Barr Virus ◽

Binding Factor ◽

Epstein Barr ◽

T Cell Lines

HLA-DR and other human class II histocompatibility genes are expressed by Epstein-Barr virus-transformed B-lymphocyte cell lines but not by most T-cell leukemia lines. We determined by transcriptional run-on experiments that regulation of class II expression in these cells is at the level of gene transcription; nuclei isolated from B-cell lines actively transcribe class II mRNA, whereas nuclei from non-class II-expressing T-cell lines and from the class II transactive factor-deficient B-cell mutant 6.1.6 do not. In searching for DNA-binding proteins which might regulate transcription, we found both a ubiquitous (B1) and a B-cell-specific (B2) factor which bind to the octamer sequence ATTTGCAT 52 base pairs 5' of the cap site in the DR alpha gene. We examined the relationship of these factors to DR alpha transcription. HUT-78, a T-cell line which expresses class II mRNA constitutively, contains only the ubiquitous B1 octamer-binding factor also found in non-class II-expressing T-cell leukemias. Human fibroblast, HeLa, and melanoma cell lines similarly contain only the ubiquitous factor, even when these cells are induced to express class II mRNA by treatment with gamma interferon. Both B1 and B2 binding factors are present in the B-cell mutant 6.1.6, which nevertheless fails to transcribe class II mRNA. Although we have not ruled out the requirement of B-cell-specific octamer-binding factor B2 for class II expression in B cells, it is clear that in other cells substantial DR alpha transcription occurs in the absence of this factor.

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