Histone deacetylase inhibitors: a new class of immunosuppressors targeting a novel signal pathway essential for CD154 expression

Blood ◽  
2003 ◽  
Vol 101 (4) ◽  
pp. 1430-1438 ◽  
Author(s):  
Søren Skov ◽  
Klaus Rieneck ◽  
Lone Frier Bovin ◽  
Kresten Skak ◽  
Søren Tomra ◽  
...  

Here we report that histone deacetylase inhibitors (HDAC-i) comprise a new class of immunosuppressive agents. HDAC-i inhibited CD4 T-cell proliferation in a dose-dependent manner, which was not caused by apoptosis or decreased viability. Although early intracellular signals such as tyrosine kinase activity and elevation of intracellular calcium concentration were not affected, the characteristic aggregation of T cells following activation was completely abrogated. This correlated with diminished activation-induced expression of the adhesion molecules. HDAC-i furthermore inhibited activation-induced CD25 and CD154 expression on CD4 cells, without affecting induction of CD69. HDAC-i inhibited CD154 expression by a mechanism distinctly different from cyclosporine-mediated inhibition. HDAC-i thus inhibited interleukin 2 (IL-2)–induced CD154 expression on effector T cells and constitutively expressed CD154 on various tumor cells, events that were not affected by cyclosporine. Additional studies showed that HDAC-i treatment inhibited c-Myc expression, which was further shown to be important for CD154 gene activation. These results demonstrate pronounced T-cell inhibitory activity of HDAC-i, which may form the basis of novel therapeutic interventions against autoimmune diseases and allograft rejection.

Blood ◽  
2006 ◽  
Vol 109 (8) ◽  
pp. 3325-3332 ◽  
Author(s):  
Anders Woetmann ◽  
Paola Lovato ◽  
Karsten W. Eriksen ◽  
Thorbjørn Krejsgaard ◽  
Tord Labuda ◽  
...  

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.


2000 ◽  
Vol 74 (17) ◽  
pp. 7738-7744 ◽  
Author(s):  
Sangkon Oh ◽  
Maryna C. Eichelberger

ABSTRACT The developing immune response in the lymph nodes of mice infected with influenza virus has both Th1- and Th2-type characteristics. Modulation of the interactions between antigen-presenting cells and T cells is one mechanism that may alter the quality of the immune response. We have previously shown that the ability of dendritic cells (DC) to stimulate the proliferation of alloreactive T cells is changed by influenza virus due to viral neuraminidase (NA) activity. Here we show that DC infected with influenza virus A/PR/8/34 (PR8) stimulate T cells to produce different types of cytokines in a dose-dependent manner. Optimal amounts of the Th1-type cytokines interleukin-2 (IL-2) and gamma interferon (IFN-γ) were produced from T cells stimulated by DC infected with low doses of PR8, while the Th2-type cytokines IL-4 and IL-10 were produced only in response to DC infected with high doses of PR8. IL-2 and IFN-γ levels corresponded with T-cell proliferation and were dependent on the activity of viral NA on the DC surface. In contrast, IL-4 secretion required the treatment of T cells with NA. Since viral particles were released only from DC that are infected with high doses of PR8, our results suggest that viral NA on newly formed virus particles desialylates T-cell surface molecules to facilitate a Th2-type response. These results suggest that the activity of NA may contribute to the mixed Th-type response observed during influenza virus infection.


2005 ◽  
Vol 25 (5) ◽  
pp. 1620-1633 ◽  
Author(s):  
P. Pavan Kumar ◽  
Prabhat Kumar Purbey ◽  
Dyavar S. Ravi ◽  
Debashis Mitra ◽  
Sanjeev Galande

ABSTRACT One hallmark of human immunodeficiency virus type 1 (HIV-1) infection is the dysregulation of cytokine gene expression in T cells. Transfection of T cells with human T-cell leukemia type 1 or 2 transactivator results in the induction of the T-cell-restricted cytokine interleukin-2 (IL-2) and its receptor (IL-2Rα). However, no T-cell-specific factor(s) has been directly linked with the regulation of IL-2 and IL-2Rα transcription by influencing the promoter activity. Thymocytes from SATB1 (special AT-rich sequence binding protein 1) knockout mice have been shown to ectopically express IL-2Rα, suggesting involvement of SATB1 in its negative regulation. Here we show that SATB1, a T-cell-specific global gene regulator, binds to the promoters of human IL-2 and IL-2Rα and recruits histone deacetylase 1 (HDAC1) in vivo. SATB1 also interacts with Tat in HIV-1-infected T cells. The functional interaction between HIV-1 Tat and SATB1 requires its PDZ-like domain, and the binding of the HDAC1 corepressor occurs through the same. Furthermore, Tat competitively displaces HDAC1 that is bound to SATB1, leading to increased acetylation of the promoters in vivo. Transduction with SATB1 interaction-deficient soluble Tat (Tat 40-72) and reporter assays using a transactivation-negative mutant (C22G) of Tat unequivocally demonstrated that the displacement of HDAC1 itself is sufficient for derepression of these promoters in vivo. These results suggest a novel mechanism by which HIV-1 Tat might overcome SATB1-mediated repression in T cells.


Blood ◽  
1995 ◽  
Vol 86 (11) ◽  
pp. 4199-4205 ◽  
Author(s):  
M Brunetti ◽  
N Martelli ◽  
A Colasante ◽  
M Piantelli ◽  
P Musiani ◽  
...  

Glucocorticoid (GC)-induced apoptosis is a well-recognized physiologic regulator of murine T-cell number and function. We have analyzed its mechanisms in human mature T cells, which have been thought to be insensitive until recently. Peripheral blood T cells showed sensitivity to GC-induced apoptosis soon after the proliferative response to a mitogenic stimulation, and were also sensitive to spontaneous (ie, growth factor deprivation-dependent) apoptosis. CD8+ T cells were more sensitive to both forms than CD4+ T cells. Acquisition of sensitivity to GC-induced apoptosis was not associated with any change in number or affinity of GC receptors. Both spontaneous and GC-induced apoptosis were increased by the macromolecular synthesis inhibitors, cycloheximide (CHX) and puromycin. A positive correlation between the degree of protein synthesis inhibition and the extent of apoptosis was observed. Interleukin-2 (IL-2) IL-4, and IL-10 protected (IL-2 > IL-10 > IL-4) T cells from both forms of apoptosis in a dose-dependent manner. Our data suggest that spontaneous and GC-induced apoptosis regulate the human mature T-cell repertoire by acting early after the immune response and differentially affecting T-cell subsets.


2020 ◽  
Vol 94 (9) ◽  
Author(s):  
Talia M. Mota ◽  
Chase D. McCann ◽  
Ali Danesh ◽  
Szu-Han Huang ◽  
Dean B. Magat ◽  
...  

ABSTRACT Clinical trials investigating histone deacetylase inhibitors (HDACi) to reverse HIV-1 latency aim to expose reservoirs in antiretroviral (ARV)-treated individuals to clearance by immune effectors, yet have not driven measurable reductions in the frequencies of infected cells. We therefore investigated the effects of the class I-selective HDACi nanatinostat and romidepsin on various blocks to latency reversal and elimination, including viral splicing, antigen presentation, and CD8+ T cell function. In ex vivo CD4+ T cells from ARV-suppressed individuals, both HDACi significantly induced viral transcription, but not splicing nor supernatant HIV-1 RNA. In an HIV-1 latency model using autologous CD8+ T cell clones as biosensors of antigen presentation, neither HDACi-treated CD4+ T cell condition induced clone degranulation. Both HDACi also impaired the function of primary CD8+ T cells in viral inhibition assays, with nanatinostat causing less impairment. These findings suggest that spliced or cell-free HIV-1 RNAs are more indicative of antigen expression than unspliced HIV-RNAs and may help to explain the limited abilities of HDACi to generate CD8+ T cell targets in vivo. IMPORTANCE Antiretroviral (ARV) drug regimens suppress HIV-1 replication but are unable to cure infection. This leaves people living with HIV-1 burdened by a lifelong commitment to expensive daily medication. Furthermore, it has become clear that ARV therapy does not fully restore health, leaving individuals at elevated risk for cardiovascular disease, certain types of cancers, and neurocognitive disorders, as well as leaving them exposed to stigma. Efforts are therefore under way to develop therapies capable of curing infection. A key focus of these efforts has been on a class of drugs called histone deacetylase inhibitors (HDACi), which have the potential of exposing hidden reservoirs of HIV-1 to elimination by the immune system. Unfortunately, clinical trial results with HDACi have thus far been disappointing. In the current study, we integrate a number of experimental approaches to build a model that provides insights into the limited activity of HDACi in clinical trials and offers direction for future approaches.


2011 ◽  
Vol 286 (41) ◽  
pp. 35456-35465 ◽  
Author(s):  
Yu Wakabayashi ◽  
Taiga Tamiya ◽  
Ichiro Takada ◽  
Tomohiro Fukaya ◽  
Yuki Sugiyama ◽  
...  

Suppression of IL-2 βproduction from T cells is an important process for the immune regulation by TGF-β. However, the mechanism by which this suppression occurs remains to be established. Here, we demonstrate that Smad2 and Smad3, two major TGF-β-downstream transcription factors, are redundantly essential for TGF-β-mediated suppression of IL-2 production in CD4+ T cells using Smad2- and Smad3-deficient T cells. Both Smad2 and Smad3 were recruited into the proximal region of the IL-2 promoter in response to TGF-β. We then investigated the histone methylation status of the IL-2 promoter. Although both histone H3 lysine 9 (H3K9) and H3K27 trimethylation have been implicated in gene silencing, only H3K9 trimethylation was increased in the proximal region of the IL-2 promoter in a Smad2/3-dependent manner, whereas H3K27 trimethylation was not. The H3K9 methyltransferases Setdb1 and Suv39h1 bound to Smad3 and suppressed IL-2 promoter activity in collaboration with Smad3. Overexpression of Suv39h1 in 68-41 T cells strongly inhibited IL-2 production in response to T cell receptor stimulation irrespective of the presence or absence of TGF-β, whereas Setdb1 overexpression only slightly suppressed IL-2 production. Silencing of Suv39h1 by shRNA reverted the suppressive effect of TGF-β on IL-2 production. Furthermore, TGF-β induced Suv39h1 recruitment to the proximal region of the IL-2 promoter in wild type primary T cells; however, this was not observed in Smad2−/−Smad3+/− T cells. Thus, we propose that Smads recruit H3K9 methyltransferases Suv39h1 to the IL-2 promoter, thereby inducing suppressive histone methylation and inhibiting T cell receptor-mediated IL-2 transcription.


2002 ◽  
Vol 22 (4) ◽  
pp. 1001-1015 ◽  
Author(s):  
Koko Katagiri ◽  
Masakazu Hattori ◽  
Nagahiro Minato ◽  
Tatsuo Kinashi

ABSTRACT Activation of T cells by antigen requires adhesive interactions with antigen-presenting cells (APC) in which leukocyte function-associated antigen 1 (LFA-1) and intercellular adhesion molecules (ICAMs) are important. However, it is not well understood what signaling molecules regulate this process and how the modulation of adhesive events influences T-cell activation. Here we show that Rap1 is activated in T cells in an antigen-dependent manner and accumulated at the contact site of T-cell and antigen-loaded APC. Inhibition of Rap1 activation by a dominant-negative Rap1 or SPA-1, a Rap1 GTPase-activating protein, abrogates LFA-1-ICAM-1-mediated adhesive interactions with antigen-pulsed APC and the subsequent T-cell-receptor triggering and interleukin-2 production. Conversely, augmented antigen-dependent Rap1 activation by the expression of wild-type Rap1 enhances these responses but culminates in apoptosis by Fas and FasL. Thus, Rap1 functions as a key regulator of T-cell and APC interactions and modulates T-cell responses from productive activation to activation-induced cell death by regulating the strength of adhesive interactions. Moreover, constitutive Rap1 activation rendered T cells unresponsive with accumulation of p27Kip1. Our study indicates that the activation state of Rap1 has a decisive effect on the T-cell response to antigen.


Blood ◽  
2006 ◽  
Vol 109 (1) ◽  
pp. 244-252 ◽  
Author(s):  
Ellen Kreijveld ◽  
Hans J. P. M. Koenen ◽  
Luuk B. Hilbrands ◽  
Hans J. P. van Hooff ◽  
Irma Joosten

Abstract The induction of transplantation tolerance involves a T-cell–mediated process of immune regulation. In clinical transplantation, the use of immunosuppressive drugs that promote or facilitate this process would be highly desirable. Here, we investigated the tolerance-promoting potential of the immunosuppressive drug FK778, currently under development for clinical therapy. Using a human allogeneic in vitro model we showed that, upon T-cell receptor (TCR) triggering, FK778 induced a regulatory phenotype in CD4+CD25− T cells. Purified CD4+CD25− T cells primed in the presence of FK778 showed hyporesponsiveness upon restimulation with alloantigen in the absence of the drug. This anergic state was reversible by exogenous interleukin-2 (IL-2) and was induced independent of naturally occurring CD4+CD25+ regulatory T cells. Pyrimidine restriction was a crucial requirement for the de novo induction of regulatory activity by FK778. The FK778-induced anergic cells showed suppressor activity in a cell-cell contact–dependent manner; were CD25high, CD45RO+, CD27−, and CD62L−; and expressed cytotoxic T-lymphocyte–associated antigen-4 (CTLA-4), glucocorticoid-induced tumor necrosis factor receptor (GITR), and FoxP3. The cells revealed delayed p27kip1 degradation and enhanced phosphorylation of STAT3. In conclusion, the new drug FK778 shows tolerizing potential through the induction of a regulatory T-cell subset in CD4+CD25− T cells.


2020 ◽  
Vol 4 (10) ◽  
pp. 2143-2157 ◽  
Author(s):  
Alak Manna ◽  
Timothy Kellett ◽  
Sonikpreet Aulakh ◽  
Laura J. Lewis-Tuffin ◽  
Navnita Dutta ◽  
...  

Abstract Patients with chronic lymphocytic leukemia (CLL) are characterized by monoclonal expansion of CD5+CD23+CD27+CD19+κ/λ+ B lymphocytes and are clinically noted to have profound immune suppression. In these patients, it has been recently shown that a subset of B cells possesses regulatory functions and secretes high levels of interleukin 10 (IL-10). Our investigation identified that CLL cells with a CD19+CD24+CD38hi immunophenotype (B regulatory cell [Breg]–like CLL cells) produce high amounts of IL-10 and transforming growth factor β (TGF-β) and are capable of transforming naive T helper cells into CD4+CD25+FoxP3+ T regulatory cells (Tregs) in an IL-10/TGF-β-dependent manner. A strong correlation between the percentage of CD38+ CLL cells and Tregs was observed. CD38hi Tregs comprised more than 50% of Tregs in peripheral blood mononuclear cells (PBMCs) in patients with CLL. Anti-CD38 targeting agents resulted in lethality of both Breg-like CLL and Treg cells via apoptosis. Ex vivo, use of anti-CD38 monoclonal antibody (mAb) therapy was associated with a reduction in IL-10 and CLL patient-derived Tregs, but an increase in interferon-γ and proliferation of cytotoxic CD8+ T cells with an activated phenotype, which showed an improved ability to lyse patient-autologous CLL cells. Finally, effects of anti-CD38 mAb therapy were validated in a CLL–patient-derived xenograft model in vivo, which showed decreased percentage of Bregs, Tregs, and PD1+CD38hiCD8+ T cells, but increased Th17 and CD8+ T cells (vs vehicle). Altogether, our results demonstrate that targeting CD38 in CLL can modulate the tumor microenvironment; skewing T-cell populations from an immunosuppressive to immune-reactive milieu, thus promoting immune reconstitution for enhanced anti-CLL response.


2020 ◽  
Vol 11 ◽  
Author(s):  
Mahinbanu Mammadli ◽  
Weishan Huang ◽  
Rebecca Harris ◽  
Aisha Sultana ◽  
Ying Cheng ◽  
...  

Allogeneic hematopoietic stem cell transplantation is a potentially curative procedure for many malignant diseases. Donor T cells prevent disease recurrence via graft-versus-leukemia (GVL) effect. Donor T cells also contribute to graft-versus-host disease (GVHD), a debilitating and potentially fatal complication. Novel treatment strategies are needed which allow preservation of GVL effects without causing GVHD. Using murine models, we show that targeting IL-2-inducible T cell kinase (ITK) in donor T cells reduces GVHD while preserving GVL effects. Both CD8+ and CD4+ donor T cells from Itk-/- mice produce less inflammatory cytokines and show decrease migration to GVHD target organs such as the liver and small intestine, while maintaining GVL efficacy against primary B-cell acute lymphoblastic leukemia (B-ALL). Itk-/- T cells exhibit reduced expression of IRF4 and decreased JAK/STAT signaling activity but upregulating expression of Eomesodermin (Eomes) and preserve cytotoxicity, necessary for GVL effect. Transcriptome analysis indicates that ITK signaling controls chemokine receptor expression during alloactivation, which in turn affects the ability of donor T cells to migrate to GVHD target organs. Our data suggest that inhibiting ITK could be a therapeutic strategy to reduce GVHD while preserving the beneficial GVL effects following allo-HSCT treatment.


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