Deletion of Foxp3+ regulatory T cells in genetically targeted mice supports development of intestinal inflammation

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Boehm Franziska

2012-07-01

Full Text Available Abstract Background Mice lacking Foxp3+ regulatory T (Treg cells develop severe tissue inflammation in lung, skin, and liver with premature death, whereas the intestine remains uninflamed. This study aims to demonstrate the importance of Foxp3+ Treg for the activation of T cells and the development of intestinal inflammation. Methods Foxp3-GFP-DTR (human diphtheria toxin receptor C57BL/6 mice allow elimination of Foxp3+ Treg by treatment with Dx (diphtheria toxin. The influence of Foxp3+ Treg on intestinal inflammation was tested using the CD4+ T-cell transfer colitis model in Rag−/− C57BL/6 mice and the acute DSS-colitis model. Results Continuous depletion of Foxp3+ Treg in Foxp3-GFP-DTR mice led to dramatic weight loss and death of mice by day 28. After 10 days of depletion of Foxp3+ Treg, isolated CD4+ T-cells were activated and produced extensive amounts of IFN-γ, IL-13, and IL-17A. Transfer of total CD4+ T-cells isolated from Foxp3-GFP-DTR mice did not result in any changes of intestinal homeostasis in Rag−/− C57BL/6 mice. However, administration of DTx between days 14 and 18 after T-cell reconstitution, lead to elimination of Foxp3+ Treg and to immediate weight loss due to intestinal inflammation. This pro-inflammatory effect of Foxp3+ Treg depletion consecutively increased inflammatory cytokine production. Further, the depletion of Foxp3+ Treg from Foxp3-GFP-DTR mice increased the severity of acute dSS-colitis accompanied by 80% lethality of Treg-depleted mice. CD4+ effector T-cells from Foxp3+ Treg-depleted mice produced significantly more pro-inflammatory cytokines. Conclusion Intermittent depletion of Foxp3+ Treg aggravates intestinal inflammatory responses demonstrating the importance of Foxp3+ Treg for the balance at the mucosal surface of the intestine.

CD4+ Foxp3+ T-cells contribute to myocardial ischemia-reperfusion injury.

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Mathes, Denise; Weirather, Johannes; Nordbeck, Peter; Arias-Loza, Anahi-Paula; Burkard, Matthias; Pachel, Christina; Kerkau, Thomas; Beyersdorf, Niklas; Frantz, Stefan; Hofmann, Ulrich

2016-12-01

The present study analyzed the effect of CD4 + Forkhead box protein 3 negative (Foxp3 - ) T-cells and Foxp3 + CD4 + T-cells on infarct size in a mouse myocardial ischemia-reperfusion model. We examined the infarct size as a fraction of the area-at-risk as primary study endpoint in mice after 30minutes of coronary ligation followed by 24hours of reperfusion. CD4 + T-cell deficient MHC-II KO mice showed smaller histologically determined infarct size (34.5±4.7% in MHCII KO versus 59.4±4.9% in wildtype (WT)) and better preserved ejection fraction determined by magnetic resonance tomography (56.9±2.8% in MHC II KO versus 39.0±4.2% in WT). MHC-II KO mice also displayed better microvascular perfusion than WT mice after 24hours of reperfusion. Also CD4 + T-cell sufficient OT-II mice, which express an in this context irrelevant T-cell receptor, revealed smaller infarct sizes compared to WT mice. However, MHC-II blocking anti-I-A/I-E antibody treatment was not able to reduce infarct size indicating that autoantigen recognition is not required for the activation of CD4 + T-cells during reperfusion. Flow-cytometric analysis also did not detect CD4 + T-cell activation in heart draining lymph nodes in response to 24hours of ischemia-reperfusion. Adoptive transfer of CD4 + T-cells in CD4 KO mice increased the infarct size only when including the Foxp3 + CD25 + subset. Depletion of CD4 + Foxp3 + T-cells in DEREG mice enabling specific conditional ablation of this subset by treatment with diphtheria toxin attenuated infarct size as compared to diphtheria toxin treated WT mice. CD4 + Foxp3 + T-cells enhance myocardial ischemia-reperfusion injury. CD4 + T-cells exert injurious effects without the need for prior activation by MHC-II restricted autoantigen recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Eosinophils from eosinophilic oesophagitis patients have T cell suppressive capacity and express FOXP3.

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Lingblom, C; Wallander, J; Ingelsten, M; Bergquist, H; Bove, M; Saalman, R; Welin, A; Wennerås, C

2017-03-01

Eosinophilic esophagitis (EoE) is an antigen-driven T cell-mediated chronic inflammatory disease where food and environmental antigens are thought to have a role. Human eosinophils express the immunoregulatory protein galectin-10 and have T cell suppressive capacity similar to regulatory T cells (T regs ). We hypothesized that one function of eosinophils in EoE might be to regulate the T cell-driven inflammation in the oesophagus. This was tested by evaluating the suppressive capacity of eosinophils isolated from the blood of adult EoE patients in a mixed lymphocyte reaction. In addition, eosinophilic expression of forkhead box protein 3 (FOXP3), the canonical transcription factor of T regs , was determined by conventional and imaging flow cytometry, quantitative polymerase chain reaction (qPCR), confocal microscopy and immunoblotting. It was found that blood eosinophils from EoE patients had T cell suppressive capacity, and that a fraction of the eosinophils expressed FOXP3. A comparison of EoE eosinophils with healthy control eosinophils indicated that the patients' eosinophils had inferior suppressive capacity. Furthermore, a higher percentage of the EoE eosinophils expressed FOXP3 protein compared with the healthy eosinophils, and they also had higher FOXP3 protein and mRNA levels. FOXP3 was found in the cytosol and nucleus of the eosinophils from both the patients and healthy individuals, contrasting with the strict nuclear localization of FOXP3 in T regs . To conclude, these findings suggest that the immunoregulatory function of eosinophils may be impaired in EoE. © 2016 British Society for Immunology.

HTLV-1 modulates the frequency and phenotype of FoxP3+CD4+ T cells in virus-infected individuals

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Satou Yorifumi

2012-05-01

Full Text Available Abstract Background HTLV-1 utilizes CD4 T cells as the main host cell and maintains the proviral load via clonal proliferation of infected CD4+ T cells. Infection of CD4+ T cells by HTLV-1 is therefore thought to play a pivotal role in HTLV-1-related pathogenicity, including leukemia/lymphoma of CD4+ T cells and chronic inflammatory diseases. Recently, it has been reported that a proportion of HTLV-1 infected CD4+ T cells express FoxP3, a master molecule of regulatory T cells. However, crucial questions remain unanswered on the relationship between HTLV-1 infection and FoxP3 expression. Results To investigate the effect of HTLV-1 infection on CD4+ T-cell subsets, we used flow cytometry to analyze the T-cell phenotype and HTLV-1 infection in peripheral mononuclear cells (PBMCs of four groups of subjects, including 23 HTLV-1-infected asymptomatic carriers (AC, 10 patients with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP, 10 patients with adult T-cell leukemia (ATL, and 10 healthy donors. The frequency of FoxP3+ cells in CD4+ T cells in AC with high proviral load and patients with HAM/TSP or ATL was higher than that in uninfected individuals. The proviral load was positively correlated with the percentage of CD4+ T cells that were FoxP3+. The CD4+FoxP3+ T cells, themselves, were frequently infected with HTLV-1. We conclude that FoxP3+ T- cells are disproportionately infected with HTLV-1 during chronic infection. We next focused on PBMCs of HAM/TSP patients. The expression levels of the Treg associated molecules CTLA-4 and GITR were decreased in CD4+FoxP3+ T cells. Further we characterized FoxP3+CD4+ T-cell subsets by staining CD45RA and FoxP3, which revealed an increase in CD45RA−FoxP3low non-suppressive T-cells. These findings can reconcile the inflammatory phenotype of HAM/TSP with the observed increase in frequency of FoxP3+ cells. Finally, we analyzed ATL cells and observed not only a high frequency of FoxP3 expression

Activation of Stat-3 is involved in the induction of apoptosis after ligation of major histocompatibility complex class I molecules on human Jurkat T cells

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Skov, S; Nielsen, M; Bregenholt, S

1998-01-01

Activation of Janus tyrosine kinases (Jak) and Signal transducers and activators of transcription (Stat) after ligation of major histocompatibility complex class I (MHC-I) was explored in Jurkat T cells. Cross-linking of MHC-I mediated tyrosine phosphorylation of Tyk2, but not Jak1, Jak2, and Jak3......-probe derived from the interferon-gamma activated site (GAS) in the c-fos promoter, a common DNA sequence for Stat protein binding. An association between hSIE and Stat-3 after MHC-I ligation was directly demonstrated by precipitating Stat-3 from nuclear extracts with biotinylated hSIE probe and avidin......-coupled agarose. To investigate the function of the activated Stat-3, Jurkat T cells were transiently transfected with a Stat-3 isoform lacking the transactivating domain. This dominant-negative acting Stat-3 isoform significantly inhibited apoptosis induced by ligation of MHC-I. In conclusion, our data suggest...

Identification of a regulatory T cell specific cell surface molecule that mediates suppressive signals and induces Foxp3 expression.

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Wang, Rui; Wan, Qi; Kozhaya, Lina; Fujii, Hodaka; Unutmaz, Derya

2008-07-16

Regulatory T (T(reg)) cells control immune activation and maintain tolerance. How T(regs) mediate their suppressive function is unclear. Here we identified a cell surface molecule, called GARP, (or LRRC32), which within T cells is specifically expressed in T(regs) activated through the T cell receptor (TCR). Ectopic expression of GARP in human naïve T (T(N)) cells inhibited their proliferation and cytokine secretion upon TCR activation. Remarkably, GARP over-expression in T(N) cells induced expression of T(reg) master transcription factor Foxp3 and endowed them with a partial suppressive function. The extracellular but not the cytoplasmic region of GARP, was necessary for these functions. Silencing Foxp3 in human T(reg) cells reduced expression of GARP and attenuated their suppressive function. However, GARP function was not affected when Foxp3 was downregulated in GARP-overexpressing cells, while silencing GARP in Foxp3-overexpressing cells reduced their suppressive activity. These findings reveal a novel cell surface molecule-mediated regulatory mechanism, with implications for modulating aberrant immune responses.

Identification of a regulatory T cell specific cell surface molecule that mediates suppressive signals and induces Foxp3 expression.

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Rui Wang

2008-07-01

Full Text Available Regulatory T (T(reg cells control immune activation and maintain tolerance. How T(regs mediate their suppressive function is unclear. Here we identified a cell surface molecule, called GARP, (or LRRC32, which within T cells is specifically expressed in T(regs activated through the T cell receptor (TCR. Ectopic expression of GARP in human naïve T (T(N cells inhibited their proliferation and cytokine secretion upon TCR activation. Remarkably, GARP over-expression in T(N cells induced expression of T(reg master transcription factor Foxp3 and endowed them with a partial suppressive function. The extracellular but not the cytoplasmic region of GARP, was necessary for these functions. Silencing Foxp3 in human T(reg cells reduced expression of GARP and attenuated their suppressive function. However, GARP function was not affected when Foxp3 was downregulated in GARP-overexpressing cells, while silencing GARP in Foxp3-overexpressing cells reduced their suppressive activity. These findings reveal a novel cell surface molecule-mediated regulatory mechanism, with implications for modulating aberrant immune responses.

Neuropilin 1 deficiency on CD4+Foxp3+ regulatory T cells impairs mouse melanoma growth

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Hutzler, Marina; Abel, Simone; Alter, Christina; Stockmann, Christian; Kliche, Stefanie; Albert, Juliane; Sparwasser, Tim; Sakaguchi, Shimon; Westendorf, Astrid M.; Schadendorf, Dirk; Buer, Jan; Helfrich, Iris

2012-01-01

Infiltration of Foxp3+ regulatory T (T reg) cells is considered to be a critical step during tumor development and progression. T reg cells supposedly suppress locally an effective anti-tumor immune response within tumor tissues, although the precise mechanism by which T reg cells infiltrate the tumor is still unclear. We provide evidence that Neuropilin 1 (Nrp-1), highly expressed by Foxp3+ T reg cells, regulates the immunological anti-tumor control by guiding T reg cells into the tumor in response to tumor-derived vascular endothelial growth factor (VEGF). We demonstrate for the first time that T cell–specific ablation of Nrp-1 expression results in a significant breakdown in tumor immune escape in various transplantation models and in a spontaneous, endogenously driven melanoma model associated with strongly reduced tumor growth and prolonged tumor-free survival. Strikingly, numbers of tumor-infiltrating Foxp3+ T reg cells were significantly reduced accompanied by enhanced activation of CD8+ T cells within tumors of T cell–specific Nrp-1–deficient mice. This phenotype can be reversed by adoptive transfer of Nrp-1+ T reg cells from wild-type mice. Thus, our data strongly suggest that Nrp-1 acts as a key mediator of Foxp3+ T reg cell infiltration into the tumor site resulting in a dampened anti-tumor immune response and enhanced tumor progression. PMID:23045606

FOXP3 renders activated human regulatory T cells resistant to restimulation-induced cell death by suppressing SAP expression.

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Katz, Gil; Voss, Kelsey; Yan, Toria F; Kim, Yong Chan; Kortum, Robert L; Scott, David W; Snow, Andrew L

2018-05-01

Restimulation-induced cell death (RICD) is an apoptotic program that regulates effector T cell expansion, triggered by repeated stimulation through the T cell receptor (TCR) in the presence of interleukin-2 (IL-2). Although CD4 + regulatory T cells (Tregs) consume IL-2 and experience frequent TCR stimulation, they are highly resistant to RICD. Resistance in Tregs is dependent on the forkhead box P3 (FOXP3) transcription factor, although the mechanism remains unclear. T cells from patients with X-linked lymphoproliferative disease (XLP-1), that lack the adaptor molecule SLAM-associated protein (SAP), are also resistant to RICD. Here we demonstrate that normal Tregs express very low levels of SAP compared to conventional T cells. FOXP3 reduces SAP expression by directly binding to and repressing the SH2D1A (SAP) promoter. Indeed, ectopic SAP expression restores RICD sensitivity in human FOXP3 + Tregs. Our findings illuminate the mechanism behind FOXP3-mediated RICD resistance in Tregs, providing new insight into their long-term persistence. Published by Elsevier Inc.

Foxp3 expression in human cancer cells

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Gourgoulianis Konstantinos I

2008-04-01

Full Text Available Abstract Objective Transcription factor forkhead box protein 3 (Foxp3 specifically characterizes the thymically derived naturally occurring regulatory T cells (Tregs. Limited evidence indicates that it is also expressed, albeit to a lesser extent, in tissues other than thymus and spleen, while, very recently, it was shown that Foxp3 is expressed by pancreatic carcinoma. This study was scheduled to investigate whether expression of Foxp3 transcripts and mature protein occurs constitutively in various tumor types. Materials and methods Twenty five tumor cell lines of different tissue origins (lung cancer, colon cancer, breast cancer, melanoma, erythroid leukemia, acute T-cell leukemia were studied. Detection of Foxp3 mRNA was performed using both conventional RT-PCR and quantitative real-time PCR while protein expression was assessed by immunocytochemistry and flow cytometry, using different antibody clones. Results Foxp3 mRNA as well as Foxp3 protein was detected in all tumor cell lines, albeit in variable levels, not related to the tissue of origin. This expression correlated with the expression levels of IL-10 and TGFb1. Conclusion We offer evidence that Foxp3 expression, characterizes tumor cells of various tissue origins. The biological significance of these findings warrants further investigation in the context of tumor immune escape, and especially under the light of current anti-cancer efforts interfering with Foxp3 expression.

Histone methylation mediates plasticity of human FOXP3(+) regulatory T cells by modulating signature gene expressions.

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He, Haiqi; Ni, Bing; Tian, Yi; Tian, Zhiqiang; Chen, Yanke; Liu, Zhengwen; Yang, Xiaomei; Lv, Yi; Zhang, Yong

2014-03-01

CD4(+) FOXP3(+) regulatory T (Treg) cells constitute a heterogeneous and plastic T-cell lineage that plays a pivotal role in maintaining immune homeostasis and immune tolerance. However, the fate of human Treg cells after loss of FOXP3 expression and the epigenetic mechanisms contributing to such a phenotype switch remain to be fully elucidated. In the current study, we demonstrate that human CD4(+) CD25(high) CD127(low/-) Treg cells convert to two subpopulations with distinctive FOXP3(+) and FOXP3(-) phenotypes following in vitro culture with anti-CD3/CD28 and interleukin-2. Digital gene expression analysis showed that upon in vitro expansion, human Treg cells down-regulated Treg cell signature genes, such as FOXP3, CTLA4, ICOS, IKZF2 and LRRC32, but up-regulated a set of T helper lineage-associated genes, especially T helper type 2 (Th2)-associated, such as GATA3, GFI1 and IL13. Subsequent chromatin immunoprecipitation-sequencing of these subpopulations yielded genome-wide maps of their H3K4me3 and H3K27me3 profiles. Surprisingly, reprogramming of Treg cells was associated with differential histone modifications, as evidenced by decreased abundance of permissive H3K4me3 within the down-regulated Treg cell signature genes, such as FOXP3, CTLA4 and LRRC32 loci, and increased abundance of H3K4me3 within the Th2-associated genes, such as IL4 and IL5; however, the H3K27me3 modification profile was not significantly different between the two subpopulations. In conclusion, this study revealed that loss of FOXP3 expression from human Treg cells during in vitro expansion can induce reprogramming to a T helper cell phenotype with a gene expression signature dominated by Th2 lineage-associated genes, and that this cell type conversion may be mediated by histone methylation events. © 2013 John Wiley & Sons Ltd.

Histone methylation mediates plasticity of human FOXP3+ regulatory T cells by modulating signature gene expressions

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He, Haiqi; Ni, Bing; Tian, Yi; Tian, Zhiqiang; Chen, Yanke; Liu, Zhengwen; Yang, Xiaomei; Lv, Yi; Zhang, Yong

2014-01-01

CD4+ FOXP3+ regulatory T (Treg) cells constitute a heterogeneous and plastic T-cell lineage that plays a pivotal role in maintaining immune homeostasis and immune tolerance. However, the fate of human Treg cells after loss of FOXP3 expression and the epigenetic mechanisms contributing to such a phenotype switch remain to be fully elucidated. In the current study, we demonstrate that human CD4+ CD25high CD127low/− Treg cells convert to two subpopulations with distinctive FOXP3+ and FOXP3− phenotypes following in vitro culture with anti-CD3/CD28 and interleukin-2. Digital gene expression analysis showed that upon in vitro expansion, human Treg cells down-regulated Treg cell signature genes, such as FOXP3, CTLA4, ICOS, IKZF2 and LRRC32, but up-regulated a set of T helper lineage-associated genes, especially T helper type 2 (Th2)-associated, such as GATA3, GFI1 and IL13. Subsequent chromatin immunoprecipitation-sequencing of these subpopulations yielded genome-wide maps of their H3K4me3 and H3K27me3 profiles. Surprisingly, reprogramming of Treg cells was associated with differential histone modifications, as evidenced by decreased abundance of permissive H3K4me3 within the down-regulated Treg cell signature genes, such as FOXP3, CTLA4 and LRRC32 loci, and increased abundance of H3K4me3 within the Th2-associated genes, such as IL4 and IL5; however, the H3K27me3 modification profile was not significantly different between the two subpopulations. In conclusion, this study revealed that loss of FOXP3 expression from human Treg cells during in vitro expansion can induce reprogramming to a T helper cell phenotype with a gene expression signature dominated by Th2 lineage-associated genes, and that this cell type conversion may be mediated by histone methylation events. PMID:24152290

Immunologic targeting of FOXP3 in inflammatory breast cancer cells.

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Smita Nair

Full Text Available The forkhead transcription factor FOXP3 is necessary for induction of regulatory T lymphocytes (Tregs and their immunosuppressive function. We have previously demonstrated that targeting Tregs by vaccination of mice with murine FOXP3 mRNA-transfected dendritic cells (DCs elicits FOXP3-specific T cell responses and enhances tumor immunity. It is clear that FOXP3 expression is not restricted to T-cell lineage and herein, using RT-PCR, flow cytometry, and western immunoblot we demonstrate for the first time that FOXP3 is expressed in inflammatory breast cancer (IBC cells, SUM149 (triple negative, ErbB1-activated and SUM190 (ErbB2-overexpressing. Importantly, FOXP3-specific T cells generated in vitro using human FOXP3 RNA-transfected DCs as stimulators efficiently lyse SUM149 cells. Interestingly, an isogenic model (rSUM149 derived from SUM149 with an enhanced anti-apoptotic phenotype was resistant to FOXP3-specific T cell mediated lysis. The MHC class I cellular processing mechanism was intact in both cell lines at the protein and transcription levels suggesting that the resistance to cytolysis by rSUM149 cells was not related to MHC class I expression or to the MHC class I antigen processing machinery in these cells. Our data suggest that FOXP3 may be an effective tumor target in IBC cells however increased anti-apoptotic signaling can lead to immune evasion.

FOXP3-specific immunity

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Andersen, Mads Hald

2013-01-01

Forkhead box P3 (FOXP3)-specific cytotoxic CD8(+) T cells are present among human peripheral blood mononuclear cells (PBMCs), especially in cancer patients. Such T lymphocytes are able not only to specifically recognize dendritic cells (DCs) that have been exposed to recombinant FOXP3 and regulat...... and regulatory T cells, but also to kill FOXP3(+) malignant T cells. The natural occurrence of FOXP3-specific cytotoxic T lymphocytes among human PBMCs suggests a general role for these cells in the complex network of immune regulation....

The role of Foxp3+ regulatory T cells in liver transplant tolerance.

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Li, W; Carper, K; Zheng, X X; Kuhr, C S; Reyes, J D; Liang, Y; Perkins, D L; Thomson, A W; Perkins, J D

2006-12-01

The liver has long been considered a tolerogenic organ that favors the induction of peripheral tolerance. The mechanisms underlying liver tolerogenicity remain largely undefined. In this study, we characterized Foxp3-expressing CD4+ CD25+ regulatory T cells (Treg) in liver allograft recipients and examined the role of Treg in inherent liver tolerogenicity by employing the mouse spontaneous liver transplant tolerance model. Orthotopic liver transplantation was performed from C57BL/10 (H2b) to C3H/HeJ (H2k) mice. The percentage of CD4+ CD25+ Treg was expanded in the liver grafts and recipient spleens from day 5 up to day 100 posttransplantation, associated with high intracellular Foxp3 and CTLA4 expression. Immunohistochemistry further demonstrated significant numbers of Foxp3+ cells in the liver grafts and recipient spleens and increased transforming growth factor beta expression in the recipient spleens throughout the time courses. Adoptive transfer of spleen cells from the long-term liver allograft survivors significantly prolonged donor heart graft survival. Depletion of recipient CD4+ CD25+ Treg using anti-CD25 monoclonal antibody (250 microg/d) induced acute liver allograft rejection, associated with elevated anti-donor T-cell proliferative responses, CTL and natural killer activities, enhanced interleukin (IL)-2, interferon-gamma, IL-10, and decreased IL-4 production, and decreased T-cell apoptotic activity in anti-CD25-treated recipients. Moreover, CTLA4 blockade by anti-CTLA4 monoclonal antibody administration exacerbated liver graft rejection when combined with anti-CD25 monoclonal antibody. Thus, Foxp3+ CD4+ CD25+ Treg appear to underpin spontaneous acceptance of major histocompatability complex- mismatched liver allografts in mice. CTLA4, IL-4, and apoptosis of alloreactive T cells appear to contribute to the function of Treg and regulation of graft outcome.

Inhibition of FOXP3/NFAT interaction enhances T cell function after TCR stimulation

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Lozano, Teresa; Villanueva, Lorea; Durántez, Maika; Gorraiz, Marta; Ruiz, Marta; Belsúe, Virginia; Riezu-Boj, José I.; Hervás-Stubbs, Sandra; Oyarzábal, Julen; Bandukwala, Hozefa; Lourenço, Ana R.; Coffer, Paul J.; Sarobe, Pablo; Prieto, Jesús; Casares, Noelia; Lasarte, Juan J.

2015-01-01

Regulatory T cell (Treg) activity is modulated by a cooperative complex between the transcription factor NFAT and FOXP3, a lineage specification factor for Tregs. FOXP3/NFAT interaction is required to repress expression of IL-2, upregulate expression of the Treg markers CTLA4 and CD25, and confer

FoxP3 mRNA splice forms in synovial CD4+ T cells in rheumatoid arthritis and psoriatic arthritis

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Ryder, L Rebekka; Bartels, Else Marie; Woetmann, Anders

2012-01-01

Our aim was to elucidate the relative amount of the different splice forms of FoxP3 mRNA in CD4+ T cells in peripheral blood (PB) compared to synovial fluid (SF) in RA and PsA patients. FoxP3 mRNA was measured using a quantitative real-time PCR method. CD4+ T cells were isolated from 17 paired...... samples of PB and SF from RA and PsA patients, and PB from 10 controls. FoxP3fl and FoxP3Δ2 mRNA was significantly increased (6.7 and 2.1-fold, respectively) in PB CD4+ T cells from RA patients compared to controls. FoxP3fl and Δ2 mRNA in SF CD4+ T cells was increased compared to controls in sero......-negative RA and PsA, but not in sero-positive RA patients, who had a high FoxP3 expression in both PB and SF. The FoxP3Δ2Δ7 mRNA was barely detectable in patient samples, and not at all in healthy individuals. We provide evidence of an increased expression of FoxP3 splice forms in synovial CD4+ T cells from...

Induced Foxp3+ T cells colonising tolerated allografts exhibit the hypomethylation pattern typical of mature regulatory T cells.

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Robert eHilbrands

2016-04-01

Full Text Available Regulatory T cells expressing the transcription factor Foxp3 require acquisition of a specific hypomethylation pattern to ensure optimal functional commitment, limited lineage plasticity and long-term maintenance of tolerance. A better understanding of the molecular mechanisms involved in the generation of these epigenetic changes in vivo will contribute to the clinical exploitation of Foxp3+Treg. Here we show that both in vitro and in vivo generated antigen specific Foxp3+Treg can acquire Treg-specific epigenetic characteristics and prevent skin graft rejection in an animal model.

Hypomethylation of the Treg-Specific Demethylated Region in FOXP3 Is a Hallmark of the Regulatory T-cell Subtype in Adult T-cell Leukemia.

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Shimazu, Yayoi; Shimazu, Yutaka; Hishizawa, Masakatsu; Hamaguchi, Masahide; Nagai, Yuya; Sugino, Noriko; Fujii, Sumie; Kawahara, Masahiro; Kadowaki, Norimitsu; Nishikawa, Hiroyoshi; Sakaguchi, Shimon; Takaori-Kondo, Akifumi

2016-02-01

Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1. Because of its immunosuppressive property and resistance to treatment, patients with ATL have poor prognoses. ATL cells possess the regulatory T cell (Treg) phenotype, such as CD4 and CD25, and usually express forkhead box P3 (FOXP3). However, the mechanisms of FOXP3 expression and its association with Treg-like characteristics in ATL remain unclear. Selective demethylation of the Treg-specific demethylated region (TSDR) in the FOXP3 gene leads to stable FOXP3 expression and defines natural Tregs. Here, we focus on the functional and clinical relationship between the epigenetic pattern of the TSDR and ATL. Analysis of DNA methylation in specimens from 26 patients with ATL showed that 15 patients (58%) hypomethylated the TSDR. The FOXP3(+) cells were mainly observed in the TSDR-hypomethylated cases. The TSDR-hypomethylated ATL cells exerted more suppressive function than the TSDR-methylated ATL cells. Thus, the epigenetic analysis of the FOXP3 gene identified a distinct subtype with Treg properties in heterogeneous ATL. Furthermore, we observed that the hypomethylation of TSDR was associated with poor outcomes in ATL. These results suggest that the DNA methylation status of the TSDR is an important hallmark to define this heterogeneous disease and to predict ATL patient prognosis. ©2015 American Association for Cancer Research.

ArtinM Mediates Murine T Cell Activation and Induces Cell Death in Jurkat Human Leukemic T Cells

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Oliveira-Brito, Patrícia Kellen Martins; Gonçalves, Thiago Eleutério; Vendruscolo, Patrícia Edivânia; Roque-Barreira, Maria Cristina

2017-01-01

The recognition of cell surface glycans by lectins may be critical for the innate and adaptive immune responses. ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus, activates antigen-presenting cells by recognizing TLR2 N-glycans and induces Th1 immunity. We recently demonstrated that ArtinM stimulated CD4+ T cells to produce proinflammatory cytokines. Here, we further studied the effects of ArtinM on adaptive immune cells. We showed that ArtinM activates murine CD4+ and CD8+ T cells, augmenting their positivity for CD25, CD69, and CD95 and showed higher interleukin (IL)-2 and interferon (IFN)-γ production. The CD4+ T cells exhibited increased T-bet expression in response to ArtinM, and IL-2 production by CD4+ and CD8+ T cells depended on the recognition of CD3εγ-chain glycans by ArtinM. The ArtinM effect on aberrantly-glycosylated neoplastic lymphocytes was studied in Jurkat T cells, in which ArtinM induced IL-2, IFN-γ, and IL-1β production, but decreased cell viability and growth. A higher frequency of AnnexinV- and propidium iodide-stained cells demonstrated the induction of Jurkat T cells apoptosis by ArtinM, and this apoptotic response was reduced by caspases and protein tyrosine kinase inhibitors. The ArtinM effects on murine T cells corroborated with the immunomodulatory property of lectin, whereas the promotion of Jurkat T cells apoptosis may reflect a potential applicability of ArtinM in novel strategies for treating lymphocytic leukemia. PMID:28665310

Phenotypically non-suppressive cells predominate among FoxP3-positive cells in oral lichen planus.

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Schreurs, Olav; Karatsaidis, Andreas; Schenck, Karl

2016-11-01

Oral lichen planus (OLP) is a common T-cell-dominated oral chronic inflammatory disease occurring in periods of remission, quiescence, activity with pronounced inflammation, and acute ulceration. Cell infiltrates in OLP contain varying numbers of CD4 + T cells expressing the transcription factor FoxP3. FoxP3 + CD4 + T cells are, however, a heterogeneous cell population containing suppressive and non-suppressive cells, and their distribution in infiltrates from OLP is unknown. Biopsies were taken from normal oral mucosa (n = 8) and OLP lesions (n = 19), and a set of in situ methods for the determination of the functional phenotype of FoxP3 + CD4 + T cells was applied. Numbers of FoxP3 + CD4 + T cells were highest in the atrophic form of the disease, yet low in the ulcerative form. The main FoxP3 + CD4 + T-cell population observed was FoxP3 + CD45RA - CD25 + CD45RO + and CD15s - , a phenotype delineating a non-suppressive subset. Numbers of cells with an actively suppressing phenotype (FoxP3 + CD45RA - CD25 + CD45RO + and CD15s + ) were, however, about twice as high in reticular lesions as compared with the atrophic form. Many FoxP3 + CD4 + T cells expressed T-bet, the hallmark transcription factor for IFN-γ-producing T cells, indicating that they may enhance immune and inflammatory responses rather than suppress them. The absence of actively suppressing FoxP3 + CD4 + T cells may in part explain why OLP is a remarkably persisting condition, in spite of the presence of substantially high numbers of FoxP3 + CD4 + T cells. The findings emphasize that it is crucial to examine not only numbers but also functional phenotype of FoxP3 + CD4 + T cells in human tissues. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Single-cell analysis reveals a link between CD3- and CD59-mediated signaling pathways in Jurkat T cells

International Nuclear Information System (INIS)

Lipp, A. M.

2012-01-01

Elevation of intracellular free calcium concentration ([Ca2+]i) is a key signal during T cell activation and is commonly used as a read-out parameter for stimulation of T cell signaling. Upon T cell stimulation a variety of calcium signals is produced by individual cells of the T cell population and the type of calcium signal strongly influences cell fate decisions. The heterogeneous nature of T cells is masked in ensemble measurements, which highlights the need for single-cell measurements. In this study we used single-cell calcium measurements in Jurkat cells to investigate signaling pathways, which are triggered by different proteins, namely CD3 and CD59. By application of an automated cluster algorithm the presented assay provides unbiased analysis of a large data set of individual calcium time traces generated by the whole cell population. By using this method we could demonstrate that the Jurkat population generates heterogeneous calcium signals in a stimulus-dependent manner. Furthermore, our data revealed the existence of a link between CD3- and CD59-mediated signaling pathways. Single-cell calcium measurements in Jurkat cells expressing different levels of the T cell receptor (TCR) complex indicated that CD59-mediated calcium signaling is critically dependent on TCR surface expression levels. In addition, triggering CD59-mediated calcium signaling resulted in down-regulation of TCR surface expression levels, which is known to happen upon direct TCR triggering too. Moreover, by using siRNA-mediated protein knock-downs and protein knock-out Jurkat mutants we could show that CD3- and CD59-mediated calcium signaling require identical key proteins. We therefore explored by which mechanism CD59-mediated signaling couples into TCR-mediated signaling. Fluorescence recovery after photobleaching (FRAP) experiments and live-cell protein-protein interaction assays provided no evidence of a direct physical interaction between CD3- and CD59-mediated signaling pathways

Contribution of Mesenteric Lymph Nodes and GALT to the Intestinal Foxp3+ Regulatory T-Cell CompartmentSummary

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Duke Geem

2016-05-01

Full Text Available Background & Aims: Foxp3+ regulatory T cells (Tregs in the intestine promote immune tolerance to enteric antigens. Previous studies have shown that C-C chemokine receptor 7 (CCR7-dependent migration of intestinal dendritic cells to the mesenteric lymph nodes (mLN is involved in peripheral Foxp3+ Treg accumulation in the intestine and the establishment of oral tolerance. However, the relative contribution of this CCR7+ dendritic cell–mLN–Treg axis to the total intestinal Foxp3+ Treg pool during the steady-state remains unclear. In this study, the contribution of CCR7, as well as the mLN and gut-associated lymphoid tissue (GALT, to the intestinal Foxp3+ Treg compartment in the small intestine (SI and large intestine (LI was assessed. Methods: Intestinal Foxp3+ Tregs were quantitated in Ccr7-/- mice and in mice devoid of secondary lymphoid organs—including mLN and GALT—owing to a deficiency in lymphotoxin (LT signaling. Specific analyses of Foxp3+Helios+ thymically derived (tTregs and Foxp3+Helios- peripherally derived (pTregs in the SI and LI, as well as the role for the mLN in supporting Foxp3+ pTreg development using the B6.Cg-Tg(TcraTcrb425Cbn/J/ovalbumin (OVA feeding system, were performed. Results: Foxp3+ Tregs were enriched in the intestine relative to the mLN, independent of CCR7. In the absence of the mLN and GALT, normal frequency and numbers of Foxp3+ Tregs were observed in LTα-deficient (Lta-/- mice. However, Foxp3+Helios- pTregs were decreased in the SI of Lta-/- mice, corresponding with defective Foxp3+ pTreg expansion to OVA. In the LI, however, the proportion of Foxp3+Helios- pTregs and Foxp3+ pTreg induction to OVA was comparable between Lta-/- and Lta+/+ mice, which coincided with preferential expression of Treg-inducing/immunoregulatory cytokines. Conclusions: The overall size of the intestinal Foxp3+Treg pool is not impacted significantly by CCR7, mLN, or GALT during the steady-state. However, m

CD147 (Basigin/Emmprin) identifies FoxP3+CD45RO+CTLA4+-activated human regulatory T cells.

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Solstad, Therese; Bains, Simer Jit; Landskron, Johannes; Aandahl, Einar Martin; Thiede, Bernd; Taskén, Kjetil; Torgersen, Knut Martin

2011-11-10

Human CD4(+)FoxP3(+) T cells are functionally and phenotypically heterogeneous providing plasticity to immune activation and regulation. To better understand the functional dynamics within this subset, we first used a combined strategy of subcellular fractionation and proteomics to describe differences at the protein level between highly purified human CD4(+)CD25(+) and CD4(+)CD25(-) T-cell populations. This identified a set of membrane proteins highly expressed on the cell surface of human regulatory T cells (Tregs), including CD71, CD95, CD147, and CD148. CD147 (Basigin or Emmprin) divided CD4(+)CD25(+) cells into distinct subsets. Furthermore, CD147, CD25, FoxP3, and in particular CTLA-4 expression correlated. Phenotypical and functional analyses suggested that CD147 marks the switch between resting (CD45RA(+)) and activated (CD45RO(+)) subsets within the FoxP3(+) T-cell population. Sorting of regulatory T cells into CD147(-) and CD147(+) populations demonstrated that CD147 identifies an activated and highly suppressive CD45RO(+) Treg subset. When analyzing CD4(+) T cells for their cytokine producing potential, CD147 levels grouped the FoxP3(+) subset into 3 categories with different ability to produce IL-2, TNF-α, IFN-γ, and IL-17. Together, this suggests that CD147 is a direct marker for activated Tregs within the CD4(+)FoxP3(+) subset and may provide means to manipulate cells important for immune homeostasis.

Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome

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Pedersen, Martin Bjerregård; Hamilton-Dutoit, Stephen Jacques; Bendix, Knud

2014-01-01

Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome.......Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome....

[Increased expressions of peripheral PD-1+ lymphocytes and CD4+CD25+FOXP3+ T cells in gastric adenocarcinoma patients].

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Li, Hao; Li, Songyan; Hu, Shidong; Zou, Guijun; Hu, Zilong; Wei, Huahua; Wang, Yufeng; Du, Xiaohui

2017-01-01

Objective To detect the frequencies of peripheral programmed death-1 + (PD-1 + ) lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in patients with gastric adenocarcinoma. Methods The study enrolled 29 patients with gastric adenocarcinoma and 29 age- and sex-matched healthy controls. Frequencies of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells were detected using flow cytometry. Results The number of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood was higher in patients with gastric adenocarcinoma than that in the control group. Moreover, linear correlation analysis indicated a positive correlation between PD-1 expression and frequency of CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood of the patients. Conclusion Gastric adenocarcinoma patients present with increased PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in the peripheral blood.

Total glucosides of paeony induces regulatory CD4(+)CD25(+) T cells by increasing Foxp3 demethylation in lupus CD4(+) T cells.

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Zhao, Ming; Liang, Gong-ping; Tang, Mei-ni; Luo, Shuang-yan; Zhang, Jing; Cheng, Wen-jing; Chan, Tak-mao; Lu, Qian-jin

2012-05-01

Total glucosides of paeony (TGP), an active compound extracted from Paeony root, has been used in therapy for autoimmune diseases. However the molecular mechanism of TGP in the prevention of autoimmune response remains unclear. In this study, we found that TGP treatment significantly increased the percentage and number of Treg cells in lupus CD4(+) T cells. Further investigation revealed that treatment with TGP increased the expression of Foxp3 in lupus CD4(+) T cells by down-regulating Foxp3 promoter methylation levels. However, we couldn't observe similar results in healthy control CD4(+) T cells treated by TGP. Moreover, our results also showed that IFN-γ and IL-2 expression was enhanced in TGP-treated lupus CD4(+) T cells. These findings indicate that TGP inhibits autoimmunity in SLE patients possibly by inducing Treg cell differentiation, which may in turn be due to its ability to regulate the methylation status of the Foxp3 promoter and activate IFN-γ and IL-2 signaling. Copyright © 2012 Elsevier Inc. All rights reserved.

A Lactobacillus rhamnosus strain induces a heme oxygenase dependent increase in Foxp3+ regulatory T cells.

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Khalil Karimi

Full Text Available We investigated the consequences of feeding with a Lactobacillus species on the immune environment in GALT, and the role of dendritic cells and heme oxygenase-1 in mediating these responses. Feeding with a specific strain of Lactobacillus rhamnosus induced a significant increase in CD4+CD25+Foxp3+ functional regulatory T cells in GALT. This increase was greatest in the mesenteric lymph nodes and associated with a marked decrease in TNF and IFNγ production. Dendritic cell regulatory function and HO-1 expression was also increased. The increase in Foxp3+ T cells could be prevented by treatment with a heme oxygenase inhibitor. However, neither inhibition of heme oxygenase nor blockade of IL-10 and TGFβ prevented the inhibition of inflammatory cytokine production. In conclusion Lactobacillus feeding induced a tolerogenic environment in GALT. HO-1 was critical to the enhancement of Foxp3+ regulatory T cells while additional, as yet unknown, pathways were involved in the down-regulation of inflammatory cytokine production by T cells.

Foxp3-dependent transformation of human primary CD4+ T lymphocytes by the retroviral protein tax.

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Chen, Li; Liu, Dan; Zhang, Yang; Zhang, Huan; Cheng, Hua

2015-10-23

The retroviral Tax proteins of human T cell leukemia virus type 1 and 2 (HTLV-1 and -2) are highly homologous viral transactivators. Both viral proteins can immortalize human primary CD4+ memory T cells, but when expressed alone they rarely transform T cells. In the present study, we found that the Tax proteins displayed a differential ability to immortalize human CD4+Foxp3+ T cells with characteristic expression of CTLA-4 and GITR. Because epidermal growth factor receptor (EGFR) was reportedly expressed and activated in a subset of CD4+Foxp3+ T cells, we introduced an activated EGFR into Tax-immortalized CD4+Foxp3+ T cells. We observed that these modified cells were grown independently of exogenous IL-2, correlating with a T cell transformation phenotype. In Tax-immortalized CD4+Foxp3- T cells, ectopic expression of Foxp3 was a prerequisite for Tax transformation of T cells. Accordingly, treatment of the transformed T cells with erlotinib, a selective inhibitor of EGFR, induced degradation of EGFR in lysosome, consequently causing T cell growth inhibition. Further, we identified autophagy as a crucial cellular survival pathway for the transformed T cells. Silencing key autophagy molecules including Beclin1, Atg5 and PI3 kinase class III (PI3KC3) resulted in drastic impairment of T cell growth. Our data, therefore, unveiled a previously unidentified role of Foxp3 in T cell transformation, providing a molecular basis for HTLV-1 transformation of CD4+Foxp3+ T cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Expansion of CD4+CD25+FOXP3+ regulatory T cells in infants of mothers with type 1 diabetes.

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Luopajärvi, Kristiina; Nieminen, Janne K; Ilonen, Jorma; Akerblom, Hans K; Knip, Mikael; Vaarala, Outi

2012-08-01

Reduced risk for type 1 diabetes (T1D) has been reported in the offspring of mothers with T1D when compared with children of affected fathers. To evaluate the hypothesis that exposure of the offspring to maternal insulin therapy induces regulatory mechanisms in utero, we compared the FOXP3 expressing regulatory T cells in cord blood (CB) of infants born to mothers with or without T1D. Cord blood mononuclear cells (CBMCs) from 20 infants with maternal T1D and from 20 infants with an unaffected mother were analyzed for the numbers of CD4+CD25+FOXP3+ cells ex vivo and after in vitro stimulation with human insulin by flow cytometry. The mRNA expression of FOXP3, NFATc2, STIM1, interleukin (IL)-10, and transforming growth factor (TGF)-β was measured by real-time reverse transcription polymerase chain reaction. The percentage of FOXP3+ cells in CD4+CD25(high) cells was higher in the CB of the infants with maternal T1D when compared with the infants of unaffected mothers (p = 0.023). After in vitro insulin stimulation an increase in the percentage of FOXP3+ cells in CD4+CD25(high) cells (p = 0.0002) as well as upregulation of FOXP3, NFATc2, STIM1, IL-10, and TGF-β transcripts in CBMCs (p mothers with T1D, in whom the disease-related PTPN22 allele was associated with reduced STIM1 and NFATc2 response in insulin-stimulated CBMCs (p = 0.007 and p = 0.014). We suggest that maternal insulin treatment induces expansion of regulatory T cells in the fetus, which might contribute to the lower risk of diabetes in children with maternal vs. paternal diabetes. © 2012 John Wiley & Sons A/S.

Micro-RNA 10a Is Increased in Feline T Regulatory Cells and Increases Foxp3 Protein Expression Following In Vitro Transfection

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Yan Wang

2017-02-01

Full Text Available CD4+CD25+Foxp3+ T regulatory (Treg cells are activated during the course of lentiviral infection and exhibit heightened suppressor function when compared to Treg cells from uninfected controls. Foxp3 is essential to Treg cell function and multiple studies have documented that lentivirus-activated Treg cells exhibit heightened Foxp3 expression when compared to Treg cells from uninfected controls. Our hypothesis was that lentivirus-induced micro-RNAs (miRNAs contribute to heightened Treg cell suppressor function by stabilizing Foxp3 expression. We demonstrated that CD4+CD25+ T cells from both feline immunodeficiency virus infected (FIV+ cats and uninfected control cats exhibit increased miRNA 10a and 21 levels compared to autologous CD4+CD25− T cells but there was no difference in the levels of these miRNAs when Treg cells from FIV+ cats were compared to Treg cells from uninfected controls. Further, there was no increase in Foxp3 mRNA following transfection of miRNA 10a or 21 into a feline cell line. However, transfection with miRNA 10a resulted in increased Foxp3 protein expression.

SA-4-1BBL costimulation inhibits conversion of conventional CD4+ T cells into CD4+ FoxP3+ T regulatory cells by production of IFN-γ.

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Shravan Madireddi

Full Text Available Tumors convert conventional CD4(+ T cells into induced CD4(+CD25(+FoxP3(+ T regulatory (iTreg cells that serve as an effective means of immune evasion. Therefore, the blockade of conventional CD4(+ T cell conversion into iTreg cells represents an attractive target for improving the efficacy of various immunotherapeutic approaches. Using a novel form of 4-1BBL molecule, SA-4-1BBL, we previously demonstrated that costimulation via 4-1BB receptor renders both CD4(+and CD8(+ T effector (Teff cells refractory to inhibition by Treg cells and increased intratumoral Teff/Treg cell ratio that correlated with therapeutic efficacy in various preclinical tumor models. Building on these studies, we herein show for the first time, to our knowledge, that signaling through 4-1BB inhibits antigen- and TGF-β-driven conversion of naïve CD4(+FoxP3(- T cells into iTreg cells via stimulation of IFN-γ production by CD4(+FoxP3(- T cells. Importantly, treatment with SA-4-1BBL blocked the conversion of CD4(+FoxP3(- T cells into Treg cells by EG.7 tumors. Taken together with our previous studies, these results show that 4-1BB signaling negatively modulate Treg cells by two distinct mechanisms: i inhibiting the conversion of CD4(+FoxP3(- T cells into iTreg cells and ii endowing Teff cells refractory to inhibition by Treg cells. Given the dominant role of Treg cells in tumor immune evasion mechanisms, 4-1BB signaling represents an attractive target for favorably tipping the Teff:Treg balance toward Teff cells with important implications for cancer immunotherapy.

Andrographolide inhibits growth of human T-cell acute lymphoblastic leukemia Jurkat cells by downregulation of PI3K/AKT and upregulation of p38 MAPK pathways

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Yang T

2016-04-01

Full Text Available Tingfang Yang,1 Shuluan Yao,2 Xianfeng Zhang,3 Yan Guo2 1Department of Pediatrics, Jining No 1 People’s Hospital, Shandong Province, People’s Republic of China; 2Department of Respiratory Medicine, Jining Medical University Affiliated Hospital, Shandong Province, People’s Republic of China; 3Department of Psychiatry, Jining Psychiatric Hospital, Shandong Province, People’s Republic of China Abstract: T-cell acute lymphoblastic leukemia (T-ALL as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro, the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 µg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. Keywords: andrographolide, PI3K, AKT, Burkitt lymphoma, Jurkat cell

Circulating gluten-specific FOXP3+CD39+ regulatory T cells have impaired suppressive function in patients with celiac disease.

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Cook, Laura; Munier, C Mee Ling; Seddiki, Nabila; van Bockel, David; Ontiveros, Noé; Hardy, Melinda Y; Gillies, Jana K; Levings, Megan K; Reid, Hugh H; Petersen, Jan; Rossjohn, Jamie; Anderson, Robert P; Zaunders, John J; Tye-Din, Jason A; Kelleher, Anthony D

2017-12-01

Celiac disease is a chronic immune-mediated inflammatory disorder of the gut triggered by dietary gluten. Although the effector T-cell response in patients with celiac disease has been well characterized, the role of regulatory T (Treg) cells in the loss of tolerance to gluten remains poorly understood. We sought to define whether patients with celiac disease have a dysfunction or lack of gluten-specific forkhead box protein 3 (FOXP3) + Treg cells. Treated patients with celiac disease underwent oral wheat challenge to stimulate recirculation of gluten-specific T cells. Peripheral blood was collected before and after challenge. To comprehensively measure the gluten-specific CD4 + T-cell response, we paired traditional IFN-γ ELISpot with an assay to detect antigen-specific CD4 + T cells that does not rely on tetramers, antigen-stimulated cytokine production, or proliferation but rather on antigen-induced coexpression of CD25 and OX40 (CD134). Numbers of circulating gluten-specific Treg cells and effector T cells both increased significantly after oral wheat challenge, peaking at day 6. Surprisingly, we found that approximately 80% of the ex vivo circulating gluten-specific CD4 + T cells were FOXP3 + CD39 + Treg cells, which reside within the pool of memory CD4 + CD25 + CD127 low CD45RO + Treg cells. Although we observed normal suppressive function in peripheral polyclonal Treg cells from patients with celiac disease, after a short in vitro expansion, the gluten-specific FOXP3 + CD39 + Treg cells exhibited significantly reduced suppressive function compared with polyclonal Treg cells. This study provides the first estimation of FOXP3 + CD39 + Treg cell frequency within circulating gluten-specific CD4 + T cells after oral gluten challenge of patients with celiac disease. FOXP3 + CD39 + Treg cells comprised a major proportion of all circulating gluten-specific CD4 + T cells but had impaired suppressive function, indicating that Treg cell dysfunction might be a key

Andrographolide inhibits growth of human T-cell acute lymphoblastic leukemia Jurkat cells by downregulation of PI3K/AKT and upregulation of p38 MAPK pathways

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Yang, Tingfang; Yao, Shuluan; Zhang, Xianfeng; Guo, Yan

2016-01-01

T-cell acute lymphoblastic leukemia (T-ALL) as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro), the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 μg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. PMID:27114702

The effect of extracorporeal photopheresis alone or in combination therapy on circulating CD4+Foxp3+CD25- T-cells in patients with leukemic cutaneous T-cell lymphoma

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Shiue, Lisa H.; Couturier, Jacob; Lewis, Dorothy E.; Wei, Caimiao; Ni, Xiao; Duvic, Madeleine

2015-01-01

Purpose Extracorporeal photopheresis (ECP) alone or in combination therapy is effective for treatment of leukemic cutaneous T-cell lymphoma (L-CTCL), but its mechanism(s) of action remain unclear. This study was designed to investigate the effect of ECP on regulatory T-cell and CD8+ T-cells in L-CTCL patients. Experimental Design Peripheral blood from 18 L-CTCL patients at baseline, Day 2, 1-month, 3-month, and 6-month post-ECP therapy were analyzed by flow cytometry for CD4+CD25+/high, CD4+Foxp3+CD25+/-, CD3+CD8+, CD3+CD8+CD69+, and CD3+CD8+IFN-γ+ T-cells. Clinical responses were assessed and correlated with changes in these T-cell subsets. Results Twelve of 18 patients achieved clinical responses. The average baseline number of CD4+CD25+/high T-cells of PBMCs in L-CTCL patients was normal (2.2%), but increased at 6-month post-therapy (4.3%, p<0.01). The average baseline number of CD4+Foxp3+ T-cells out of CD4+ T-cells in 9 evaluable patients was high (66.8±13.7%), mostly CD25 negative. The levels of CD4+Foxp3+ T cells in responders were higher (n=6, 93.1±5.7%) than non-responders (n=3, 14.2±16.0%, p<0.01), and they declined in parallel with malignant T-cells. The numbers of CD3+CD8+CD69+ and CD3+CD8+ IFN-γ+ T-cells increased at 3-month post-therapy in 5 of 6 patients studied. Conclusions ECP alone or in combination therapy might be effective in L-CTCL patients whose malignant T-cells have a CD4+Foxp3+CD25- phenotype. PMID:25772268

Detection of Tax-specific CTLs in lymph nodes of adult T-cell leukemia/lymphoma patients and its association with Foxp3 positivity of regulatory T-cell function.

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Ichikawa, Ayako; Miyoshi, Hiroaki; Arakawa, Fumiko; Kiyasu, Junichi; Sato, Kensaku; Niino, Daisuke; Kimura, Yoshizo; Yoshida, Maki; Kawano, Riko; Muta, Hiroko; Sugita, Yasuo; Ohshima, Koichi

2017-06-01

Human T-cell lymphotropic virus type (HTLV)-1 Tax is a viral protein that has been reported to be important in the proliferation of adult T-cell leukemia/lymphoma (ATLL) cells and to be a target of HTLV-1-specific cytotoxic T lymphocytes (CTLs). However, it is not clear how Tax-specific CTLs behave in lymph nodes of ATLL patients. The present study analyzed the immunostaining of Tax-specific CTLs. Furthermore, ATLL tumor cells are known to be positive for forkhead box P3 (Foxp3)and to have a regulatory T (Treg)-cell-like function. The association between T-reg function and number and activity of Tax-specific CTLs was also investigated. A total of 15 ATLL lymphoma cases with human leukocyte antigen (HLA)-A24, for which Tax has a high affinity, were selected from the files of the Department of Pathology, School of Medicine, Kurume University (Kurume, Japan) using a polymerase chain reaction (PCR) method. Immunostaining was performed for cluster of differentiation (CD) 20, CD3, CD4, CD8, T-cell intracellular antigen-1 and Foxp3 in paraffin sections, and for Tax, interferon γ and HLA-A24 in frozen sections. In addition, the staining of Tax-specific CTLs (HLA-A24-restricted) was analyzed by MHC Dextramer ® assay in frozen sections. In addition, the messenger RNA expression of Tax and HTLV-1 basic leucine zipper factor were also evaluated by reverse transcription-PCR. Immunohistochemical staining of Tax protein in lymphoma tissue revealed the presence of positive lymphoma cells ranging from 5 to 80%, and immunohistochemical staining of HLA-A24 revealed the presence of positive lymphoma cells ranging from 1 to 95%. The expression of Tax and HLA-A24 was downregulated by viral function. Foxp3, a marker for Treg cells, was expressed in 0-90% of cells. Several cases exhibited Tax-specific CTL (HLA-A24-restricted)-positive cells, and there was an inverse correlation between Tax-specific CTLs and Foxp3. However, neither Tax nor HLA-A24 expression was associated with CTL or

Plasmodium falciparum-mediated induction of human CD25Foxp3 CD4 T cells is independent of direct TCR stimulation and requires IL-2, IL-10 and TGFbeta.

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Anja Scholzen

2009-08-01

Full Text Available CD4(+CD25(+Foxp3(+ regulatory T cells (Tregs regulate disease-associated immunity and excessive inflammatory responses, and numbers of CD4(+CD25(+Foxp3(+ Tregs are increased during malaria infection. The mechanisms governing their generation, however, remain to be elucidated. In this study we investigated the role of commonly accepted factors for Foxp3 induction, TCR stimulation and cytokines such as IL-2, TGFbeta and IL-10, in the generation of human CD4(+CD25(+Foxp3(+ T cells by the malaria parasite Plasmodium falciparum. Using a co-culture system of malaria-infected red blood cells (iRBCs and peripheral blood mononuclear cells from healthy individuals, we found that two populations of Foxp3(hi and Foxp3(int CD4(+CD25(hi T cells with a typical Treg phenotype (CTLA-4(+, CD127(low, CD39(+, ICOS(+, TNFRII(+ were induced. Pro-inflammatory cytokine production was confined to the Foxp3(int subset (IFNgamma, IL-4 and IL-17 and inversely correlated with high relative levels of Foxp3(hi cells, consistent with Foxp3(hi CD4 T cell-mediated inhibition of parasite-induced effector cytokine T cell responses. Both Foxp3(hi and Foxp3(int cells were derived primarily from proliferating CD4(+CD25(- T cells with a further significant contribution from CD25(+Foxp3(+ natural Treg cells to the generation of the Foxp3(hi subset. Generation of Foxp3(hi, but not Foxp3(int, cells specifically required TGFbeta1 and IL-10. Add-back experiments showed that monocytes expressing increased levels of co-stimulatory molecules were sufficient for iRBC-mediated induction of Foxp3 in CD4 T cells. Foxp3 induction was driven by IL-2 from CD4 T cells stimulated in an MHC class II-dependent manner. However, transwell separation experiments showed that direct contact of monocytes with the cells that acquire Foxp3 expression was not required. This novel TCR-independent and therefore antigen-non specific mechanism for by-stander CD4(+CD25(hiFoxp3(+ cell induction is likely to reflect a

Proteasome inhibitor carfilzomib interacts synergistically with histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells.

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Gao, Minjie; Gao, Lu; Tao, Yi; Hou, Jun; Yang, Guang; Wu, Xiaosong; Xu, Hongwei; Tompkins, Van S; Han, Ying; Wu, Huiqun; Zhan, Fenghuang; Shi, Jumei

2014-06-01

In the present study, we investigated the interactions between proteasome inhibitor carfilzomib (CFZ) and histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells. Coexposure of cells to minimally lethal concentrations of CFZ with very low concentration of vorinostat resulted in synergistic antiproliferative effects and enhanced apoptosis in Jurkat T-leukemia cells, accompanied with the sharply increased reactive oxygen species (ROS), the striking decrease in the mitochondrial membrane potential (MMP), the increased release of cytochrome c, the enhanced activation of caspase-9 and -3, and the cleavage of PARP. The combined treatment of Jurkat cells pre-treated with ROS scavengers N-acetylcysteine (NAC) significantly blocked the loss of mitochondrial membrane potential, suggesting that ROS generation was a former event of the loss of mitochondrial membrane potential. Furthermore, NAC also resulted in a marked reduction in apoptotic cells, indicating a critical role for increased ROS generation by combined treatment. In addition, combined treatment arrested the cell cycle in G2-M phase. These results imply that CFZ interacted synergistically with vorinostat in Jurkat T-leukemia cells, which raised the possibility that the combination of carfilzomib with vorinostat may represent a novel strategy in treating T-cell Leukemia. © The Author 2014. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

Comparative Approach to Define Increased Regulatory T Cells in Different Cancer Subtypes by Combined Assessment of CD127 and FOXP3

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Marc Beyer

2011-01-01

Full Text Available In recent years an increase of functional CD4+CD25+ regulatory T cells (Treg cells has been established for patients with solid tumors, acute leukemias, and lymphomas. We have reported an expanded pool of CD4+CD25high Treg cells in patients with chronic lymphatic leukemia (CLL, multiple myeloma (MM as well as its premalignant precursor monoclonal gammopathy of undetermined significance (MGUS. In healthy individuals, low-level expression of CD127 on T cells in addition to the expression of FOXP3 has been associated with Treg cells. Here, we demonstrate that the expanded FOXP3+ T-cell population in patients with colorectal cancer, CLL, MGUS, MM, follicular lymphoma, and Hodgkin's disease are exclusively CD127low Treg cells and were strongly suppressive. A significant portion of CD127lowFOXP3+ Treg cells expressed only low levels of CD25 suggesting that the previously reported expansion of CD25+ Treg cells underestimates the true expansion. The assessment of CCR7 and CD45RA expression on the expanded CD4+CD127lowFOXP3+ Treg cells revealed an increase of both naïve as well as central and effector memory Treg cells in peripheral blood. Our data strongly support superiority of combined CD127 and FOXP3 analysis in comparison to CD25 and FOXP3 assessment for further quantification of Treg cells in malignant diseases.

Differential Activity of Voltage- and Ca2+-Dependent Potassium Channels in Leukemic T Cell Lines: Jurkat Cells Represent an Exceptional Case

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Salvador Valle-Reyes

2018-05-01

Full Text Available Activation of resting T cells relies on sustained Ca2+ influx across the plasma membrane, which in turn depends on the functional expression of potassium channels, whose activity repolarizes the membrane potential. Depending on the T-cells subset, upon activation the expression of Ca2+- or voltage-activated K+ channels, KCa or Kv, is up-regulated. In this study, by means of patch-clamp technique in the whole cell mode, we have studied in detail the characteristics of Kv and KCa currents in resting and activated human T cells, the only well explored human T-leukemic cell line Jurkat, and two additional human leukemic T cell lines, CEM and MOLT-3. Voltage dependence of activation and inactivation of Kv1.3 current were shifted up to by 15 mV to more negative potentials upon a prolonged incubation in the whole cell mode and displayed little difference at a stable state in all cell lines but CEM, where the activation curve was biphasic, with a high and low potential components. In Jurkat, KCa currents were dominated by apamine-sensitive KCa2.2 channels, whereas only KCa3.1 current was detected in healthy T and leukemic CEM and MOLT-3 cells. Despite a high proliferation potential of Jurkat cells, Kv and KCa currents were unexpectedly small, more than 10-fold lesser as compared to activated healthy human T cells, CEM and MOLT-3, which displayed characteristic Kv1.3high:KCa3.1high phenotype. Our results suggest that Jurkat cells represent perhaps a singular case and call for more extensive studies on primary leukemic T cell lines as well as a verification of the therapeutic potential of specific KCa3.1 blockers to combat acute lymphoblastic T leukemias.

THE RELATIONSHIP OF FoxP3+ T REGULATORY CELLS TO DISEASE ACTIVITY AND ANTIBODY LEVELS IN EARLY RHEUMATOID ARTHRITIS

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A. S. Avdeeva

2017-01-01

Full Text Available Objective: to analyze the relationship of the count of FoxP3+ T regulatory cells (Tregs to the clinical and laboratory parameters of disease activity and the levels of antibodies in a group of patients with early rheumatoid arthritis (RA.Subjects and methods. The investigation enrolled 45 patients with early RA (2010 ACR/EULAR criteria who had not previously received treatment with methotrexate, including 39 women; median age was 52.0 [32.5; 57.5] years; disease duration, 5 [4; 6] months, DAS28 5.01 [4.18; 5.8]; 71.1% of the patients were rheumatoid factor (RF positive and 88.9% were anti-cyclic citrullinated peptide positive. The relative and absolute counts of Treg (FoxP3+CD25+; CD152+surface; CD152+intracellular; FoxP3+CD127-; CD25+CD127-; FoxP3+ICOS+; FoxP3+CD154+; FoxP3+CD274+ were measured by immunofluorescence staining and multicolor flow cytometry. A control group consisted of 20 healthy donors who were matched for sex and age with the examined patients.Results and discussion. DАS28 was high, moderate, and low in 22 (48.9%, 20 (44.4%, and 3 (6.7% patients, respectively. As compared with the healthy donors, the patients with early RA were observed to have lower values in the percentage of FoxP3+CD25+ cells, in the percentage and absolute count of FoxP3+ICOS+ cells, in the percentage and absolute count of FoxP3+CD154+ and FoxP3+ CD274+ T cells; p<0.05 in all cases. Negative correlation was recorded between the percentage of FoxP3+CD25+ and C-reactive protein (CRP (r=-0.4; that of CD152+intracellular and DAS28 (r=-0.35, ESR (r=-0.46, CRP (r=-0.54; that of FoxP3+CD127 and CRP (r=-0.42; that of CD25+CD127 and DAS28 (r=-0.38, SDAI (r=-0.41, CDAI (r=-0.36, ESR (r=-0.39, CRP (r=-0.47; p<0.05 in all cases.The patients who were seronegative for RF were found to have higher values in the percentage of CD25+CD127, in the percentage and absolute count of Foxp3+CD154+ and Foxp3+CD274+ T lymphocytes.Conclusion. The given data may indicate that the

Bovine lactoferricin causes apoptosis in Jurkat T-leukemia cells by sequential permeabilization of the cell membrane and targeting of mitochondria

International Nuclear Information System (INIS)

Mader, Jamie S.; Richardson, Angela; Salsman, Jayme; Top, Deniz; Antueno, Roberto de; Duncan, Roy; Hoskin, David W.

2007-01-01

Bovine lactoferricin (LfcinB) is a cationic antimicrobial peptide that kills Jurkat T-leukemia cells by the mitochondrial pathway of apoptosis. However, the process by which LfcinB triggers mitochondria-dependent apoptosis is not well understood. Here, we show that LfcinB-induced apoptosis in Jurkat T-leukemia cells was preceded by LfcinB binding to, and progressive permeabilization of the cell membrane. Colloidal gold electron microscopy revealed that LfcinB entered the cytoplasm of Jurkat T-leukemia cells prior to the onset of mitochondrial depolarization. LfcinB was not internalized by endocytosis because endocytosis inhibitors did not prevent LfcinB-induced cytotoxicity. Furthermore, intracellular delivery of LfcinB via fusogenic liposomes caused the death of Jurkat T-leukemia cells, as well as normal human fibroblasts. Collectively, these findings suggest that LfcinB caused damage to the cell membrane that allowed LfcinB to enter the cytoplasm of Jurkat T-leukemia cells and mediate cytotoxicity. In addition, confocal microscopy showed that intracellular LfcinB co-localized with mitochondria in Jurkat T-leukemia cells, while flow cytometry and colloidal gold electron microscopy showed that LfcinB rapidly associated with purified mitochondria. Furthermore, purified mitochondria treated with LfcinB rapidly lost transmembrane potential and released cytochrome c. We conclude that LfcinB-induced apoptosis in Jurkat T-leukemia cells resulted from cell membrane damage and the subsequent disruption of mitochondrial membranes by internalized LfcinB

FoxP3+CD4+CD25+ T cells with regulatory properties can be cultured from colonic mucosa of patients with Crohn's disease

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Kelsen, J; Agnholt, J; Hoffmann, H J; Rømer, J L; Hvas, C L; Dahlerup, J F

2005-01-01

CD4+CD25+ regulatory T cells (Tregs) are involved in the maintenance of peripheral tolerance and ensure a balanced immune response competent of fighting pathogens and at the same time recognizing commensals as harmless. This feature is lost in Crohn's disease (CD). The forkhead/winged helix transcription factor FoxP3 is a master gene for Treg function and defects in the FoxP3 gene lead to a clinical picture similar to inflammatory bowel disease (IBD). Murine colitis can be cured by adoptive transfer of Tregs and ex vivo-generated gut-specific Tregs represent an attractive option for therapy in CD. Thus, defective Tregs could contribute to the development of CD. We cultured biopsies of colonic mucosa in the presence of high concentrations of interleukin (IL)-2 and IL-4 to overcome the anergic nature of naturally occurring CD4+CD25+ Tregs in the mucosa. We investigated the expression of FoxP3 and regulatory potential of gut-derived CD4+CD25+ T cells cultured from patients with CD and healthy individuals. The FoxP3 expression was analysed by reverse transcriptase polymerase chain reaction (RT-PCR), and the suppressive effect of FoxP3+CD4+CD25+ T cells on proliferation and cytokine production of autologous CD4+ T cells was assessed by flow cytometry. Cultured gut-derived T cells with CD4+CD25+ phenotype expressed FoxP3 and were able as the freshly isolated Tregs from peripheral blood to suppress proliferation and cytokine production of autologous CD4+ T cells. Thus, we demonstrate that FoxP3+CD4+CD25+ T cells with regulatory properties can be propagated in vitro from inflamed mucosa of CD patients, which may be of interest in adoptive immunotherapy. PMID:16045746

Zinc supplementation induces CD4+CD25+Foxp3+ antigen-specific regulatory T cells and suppresses IFN-γ production by upregulation of Foxp3 and KLF-10 and downregulation of IRF-1.

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Maywald, Martina; Rink, Lothar

2017-08-01

The essential trace element zinc plays a fundamental role in immune function and regulation since its deficiency is associated with autoimmunity, allergies, and transplant rejection. Thus, we investigated the influence of zinc supplementation on the Th1-driven alloreaction in mixed lymphocyte cultures (MLC), on generation of antigen-specific T cells, and analyzed underlying molecular mechanisms. Cell proliferation and pro-inflammatory cytokine production were monitored by [ 3 H]-thymidine proliferation assay and ELISA, respectively. Analysis of surface and intracellular T cell marker was performed by flow cytometry. Western blotting and mRNA analysis were used for Foxp3, KLF-10, and IRF-1 expression. Zinc supplementation on antigen-specific T cells in physiological doses (50 µM) provokes a significant amelioration of cell proliferation and pro-inflammatory cytokine production after reactivation compared to untreated controls. Zinc administration on MLC results in an increased induction and stabilization of CD4 + CD25 + Foxp3 + and CD4 + CD25 + CTLA-4 + T cells (p zinc-induced upregulation of Foxp3 and KLF-10 and downregulation of IRF-1. However, in resting lymphocytes zinc increases IRF-1. In summary, zinc is capable of ameliorating the allogeneic immune reaction by enhancement of antigen-specific iTreg cells due to modulation of essential molecular targets: Foxp3, KLF-10, and IRF-1. Thus, zinc can be seen as an auspicious tool for inducing tolerance in adverse immune reactions.

FOXP3+ T Regulatory Cell Modifications in Inflammatory Bowel Disease Patients Treated with Anti-TNFα Agents

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Luisa Guidi

2013-01-01

Full Text Available Treg modulation has been hypothesized as one of the mechanisms by which antitumor necrosis factor α (TNFα agents exert their action in rheumatoid arthritis (RA and inflammatory bowel disease (IBD. However, data in IBD are still conflicting. We evaluated CD4+CD25+FOXP3+ (Tregs by flow cytometry in peripheral blood from 32 adult IBD patient before (T0 and after the induction of anti-TNFα therapy (T1. Eight healthy controls (HCs were included. We also evaluated the number of FOXP3+ cells in the lamina propria (LP in biopsies taken in a subset of patients and controls. Treg frequencies were significantly increased in peripheral blood from our patients after anti-TNFα therapy compared to T0. T1 but not T0 levels were higher than HC. The increase was detectable only in clinical responders to the treatment. A negative correlation was found among delta Treg levels and the age of patients or disease duration and with the activity score of Crohn’s disease (CD. No significant differences were found in LP FOXP3+ cells. Our data suggest the possibility that in IBD patients the treatment with anti-TNFα may affect Treg percentages and that Treg modifications may correlate with clinical response, but differently in early versus late disease.

Theoretical evaluations of electro-manipulation from Jurkat T cells ...

African Journals Online (AJOL)

enoh

2012-03-01

Mar 1, 2012 ... Jurkat T cells exposed to pulsed electric fields (PEFs) ..... changes in ionic strength, surface-charge density or pH, therefore it is likely to ... loosely bound conformation. ... alone, is sufficient to trigger this protein's release (Ott et.

CD4+CD25+ T cells expressing FoxP3 in Icelandic horses affected with insect bite hypersensitivity.

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Hamza, Eman; Steinbach, Falko; Marti, Eliane

2012-07-15

Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis caused by bites of midges from the genus Culicoides. We have shown previously that peripheral blood mononuclear cells (PBMC) from IBH-affected horses produce higher levels of IL-4 and lower levels of IL-10 and TGF-β1 than those from healthy horses, suggesting that IBH is associated with a reduced regulatory immune response. FoxP3 is a crucial marker of regulatory T cells (Tregs). Here we have determined the proportion of CD4(+)CD25(+)FoxP3(+) T cells by flow cytometry in PBMC directly after isolation or after stimulation with Culicoides extract or a control antigen (Tetanus Toxoid). There were no differences between healthy and IBH horses either in the proportion of FoxP3(+)CD4(+)CD25(+) cells in freshly isolated PBMC or in the following stimulation with Tetanus Toxoid. However, upon stimulation of PBMC with the allergen, expression of FoxP3 by CD4(+)CD25(+high) and CD4(+)CD25(+dim) cells was significantly higher in healthy than in IBH horses. Addition of recombinant IL-4 to PBMC from healthy horses stimulated with the allergen significantly decreased the proportion of FoxP3 expressing cells within CD4(+)CD25(+high). These results suggest that IBH is associated with a decreased number of allergen-induced Tregs. This could be a consequence of the increased IL-4 production by PBMC of IBH-affected horses. Copyright © 2011 Elsevier B.V. All rights reserved.

Regulatory function of a novel population of mouse autoantigen-specific Foxp3 regulatory T cells depends on IFN-gamma, NO, and contact with target cells.

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Cyndi Chen

Full Text Available BACKGROUND: Both naturally arising Foxp3(+ and antigen-induced Foxp3(- regulatory T cells (Treg play a critical role in regulating immune responses, as well as in preventing autoimmune diseases and graft rejection. It is known that antigen-specific Treg are more potent than polyclonal Treg in suppressing pathogenic immune responses that cause autoimmunity and inflammation. However, difficulty in identifying and isolating a sufficient number of antigen-specific Treg has limited their use in research to elucidate the mechanisms underlying their regulatory function and their potential role in therapy. METHODOLOGY/PRINCIPAL FINDINGS: Using a novel class II MHC tetramer, we have isolated a population of CD4(+ Foxp3(- T cells specific for the autoantigen glutamic acid decarboxylase p286-300 peptide (NR286 T cells from diabetes-resistant non-obese resistant (NOR mice. These Foxp3(- NR286 T cells functioned as Treg that were able to suppress target T cell proliferation in vitro and inhibit type 1 diabetes in animals. Unexpected results from mechanistic studies in vitro showed that their regulatory function was dependent on not only IFN-gamma and nitric oxide, but also on cell contact with target cells. In addition, separating NR286 Treg from target T cells in transwell assays abolished both production of NO and suppression of target T cells, regardless of whether IFN-gamma was produced in cell cultures. Therefore, production of NO, not IFN-gamma, was cell contact dependent, suggesting that NO may function downstream of IFN-gamma in mediating regulatory function of NR286 Treg. CONCLUSIONS/SIGNIFICANCE: These studies identified a unique population of autoantigen-specific Foxp3(- Treg that can exert their regulatory function dependent on not only IFN-gamma and NO but also cell contact with target cells.

Targeting Jurkat T Lymphocyte Leukemia Cells by an Engineered Interferon-Alpha Hybrid Molecule

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Dehai Yu

2017-06-01

Full Text Available Background/Aims: Adult T-cell leukemia/lymphoma (ATL is a very aggressive T cell malignancy that carries a poor prognosis, primarily due to its resistance to chemotherapy and to life-threatening infectious complications. Interferon-alpha (IFNα has been used in combination with the anti-retroviral drug zidovudine to treat patients with ATL. However, the efficacy of long-term therapy is significantly limited due to the systemic toxicity of IFNα. Methods: We utilized phage display library screening to identify short peptides that specifically bind to Jurkat T lymphocyte leukemia cells. By fusing the Jurkat-binding peptide to the C-terminus of IFNα, we constructed an engineered chimeric IFNα molecule (IFNP for the treatment of ATL. Results: We found that IFNP exhibited significantly higher activity than wild type IFNα in inhibiting the growth of leukemia cells and inducing cell blockage at the G0/G1 phase. The synthetic IFNP molecule exerted its antitumor activity by upregulating the downstream genes involved in the STAT1 pathway and in apoptosis. Using a cell receptor binding assay, we showed that this Jurkat-binding peptide facilitated the binding affinity of IFNα to the cell surface type I IFN receptor. Conclusion: The isolated Jurkat-binding peptide significantly potentiates the therapeutic activity of IFNα in T lymphocyte leukemia cells. The engineered IFNP molecule may prove to a novel antitumor approach in the treatment of patients with ATL.

The Expression of T Cell FOXP3 and T-Bet Is Upregulated in Severe but Not Euthyroid Hashimoto’s Thyroiditis

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Stana Tokić

2016-01-01

Full Text Available Hashimoto’s thyroiditis (HT is an organ-specific autoimmune disorder characterized by progressive thyroid failure. Th1 and Treg subset of CD4+ cells have been implicated in the pathogenesis; however, less is known about their respective roles across the spectrum of HT clinical presentations. To shed more light on CD4+ subsets role in HT, we investigated the mRNA expression levels of several Th1/Treg-associated transcription factors (T-bet/ETS1, HIF1α/BLIMP1/FOXP3 in peripheral blood T cells of 10 hypothyroid, untreated HT patients, 10 hypothyroid patients undergoing hormone replacement therapy, 12 euthyroid HT subjects, and 11 healthy controls by the qRT-PCR. Compared to euthyroid HT patients and controls, both hypothyroid (2.34-fold difference versus controls, P<0.01 and thyroxine-supplemented patients (2.5-fold, P<0.001 showed an increased FOXP3 mRNA expression in T cells. Similarly, mRNA expression levels of T-bet were upregulated in severely affected but not in euthyroid HT subjects (2.37-fold and 3.2-fold, hypothyroid and thyroxine-supplemented HT patients versus controls, resp., P<0.01. By contrast, no differences in mRNA expression levels of ETS1, BLIMP1, and HIF1α were observed across the study groups. In summary, severe but not euthyroid HT was associated with robust upregulation of T-bet and FOXP3 mRNA in peripheral T cells, independent of the thyroid hormone status but proportional to disease activity.

Foxp3 overexpression in tumor cells predicts poor survival in oral squamous cell carcinoma

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Song, Jing-Jing; Zhao, Si-Jia; Fang, Juan; Ma, Da; Liu, Xiang-Qi; Chen, Xiao-Bing; Wang, Yun; Cheng, Bin; Wang, Zhi

2016-01-01

Forkhead Box P3 (Foxp3) is a regulatory T cells marker, and its expression correlates with prognosis in a number of malignancies. The aim of this study is to determine the relationship of Foxp3 expression with clinicopathological parameters and prognosis in oral squamous cell carcinoma (OSCC). Foxp3 expression was examined using immunohistochemistry (IHC) in paraffin-embedded tissue samples from 273 OSCC patients. Statistical analysis was performed to evaluate the associations between Foxp3 expression, the clinicopathologic characteristics and prognostic factors in OSCC. Foxp3 protein expression was significantly associated with lymph node metastasis (P <0.01). Both univariate and multivariate analyses revealed that Foxp3 was an independent factor for both 5 years overall survival (OS) and relapse-free survival (RFS) (both P <0.01). Patients with Foxp3 overexpression had shorter OS and RFS. Our results determined that elevated Foxp3 protein expression was a predictive factor of outcome in OSCC and could act as a promising therapeutic target

Ubiquitin-specific Protease-7 Inhibition Impairs Tip60-dependent Foxp3+ T-regulatory Cell Function and Promotes Antitumor Immunity

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Liqing Wang

2016-11-01

Full Text Available Foxp3+ T-regulatory (Treg cells are known to suppress protective host immune responses to a wide variety of solid tumors, but their therapeutic targeting is largely restricted to their transient depletion or “secondary” modulation, e.g. using anti-CTLA-4 monoclonal antibody. Our ongoing studies of the post-translational modifications that regulate Foxp3 demonstrated that the histone/protein acetyltransferase, Tip60, plays a dominant role in promoting acetylation, dimerization and function in Treg cells. We now show that the ubiquitin-specific protease, Usp7, controls Treg function largely by stabilizing the expression and promoting the multimerization of Tip60 and Foxp3. Genetic or pharmacologic targeting of Usp7 impairs Foxp3+ Treg suppressive functions, while conventional T cell responses remain intact. As a result, pharmacologic inhibitors of Usp7 can limit tumor growth in immunocompetent mice, and promote the efficacy of antitumor vaccines and immune checkpoint therapy with anti-PD1 monoclonal antibody in murine models. Hence, pharmacologic therapy with Usp7 inhibitors may have an important role in future cancer immunotherapy.

Foxp3 regulates ratio of Treg and NKT cells in a mouse model of asthma.

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Lu, Yanming; Guo, Yinshi; Xu, Linyun; Li, Yaqin; Cao, Lanfang

2015-05-01

Chronic inflammatory disorder of the airways causes asthma. Regulatory T cells (Treg cells) and Natural killer T cells (NKT cells) both play critical roles in the pathogenesis of asthma. Activation of Treg cells requires Foxp3, whereas whether Foxp3 may regulate the ratio of Treg and NKT cells to affect asthma is uncertain. In an ovalbumin (OVA)-induced mouse model of asthma, we either increased Treg cells by lentivirus-mediated forced expression of exogenous Foxp3, or increased NKT cells by stimulation with its activator α-GalCer. We found that the CD4+CD25+ Treg cells increased by forced Foxp3 expression, and decreased by α-GalCer, while the CD3+CD161+ NKT cells decreased by forced Foxp3 expression, and increased by α-GalCer. Moreover, forced Foxp3 expression, but not α-GalCer, significantly alleviated the hallmarks of asthma. Furthermore, forced Foxp3 increased levels of IL_10 and TGFβ1, and α-GalCer increased levels of IL_4 and INFγ in the OVA-treated lung. Taken together, our study suggests that Foxp3 may activate Treg cells and suppress NKT cells in asthma. Treg and NKT cells may antagonize the effects of each other in asthma.

Analysis of FOXP3+ regulatory T cells that display apparent viral antigen specificity during chronic hepatitis C virus infection.

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Shuo Li

2009-12-01

Full Text Available We reported previously that a proportion of natural CD25(+ cells isolated from the PBMC of HCV patients can further upregulate CD25 expression in response to HCV peptide stimulation in vitro, and proposed that virus-specific regulatory T cells (Treg were primed and expanded during the disease. Here we describe epigenetic analysis of the FOXP3 locus in HCV-responsive natural CD25(+ cells and show that these cells are not activated conventional T cells expressing FOXP3, but hard-wired Treg with a stable FOXP3 phenotype and function. Of approximately 46,000 genes analyzed in genome wide transcription profiling, about 1% were differentially expressed between HCV-responsive Treg, HCV-non-responsive natural CD25(+ cells and conventional T cells. Expression profiles, including cell death, activation, proliferation and transcriptional regulation, suggest a survival advantage of HCV-responsive Treg over the other cell populations. Since no Treg-specific activation marker is known, we tested 97 NS3-derived peptides for their ability to elicit CD25 response (assuming it is a surrogate marker, accompanied by high resolution HLA typing of the patients. Some reactive peptides overlapped with previously described effector T cell epitopes. Our data offers new insights into HCV immune evasion and tolerance, and highlights the non-self specific nature of Treg during infection.

MUC1 (CD227) interacts with lck tyrosine kinase in Jurkat lymphoma cells and normal T cells.

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Mukherjee, P; Tinder, T L; Basu, G D; Gendler, S J

2005-01-01

MUC1 (CD227) is a large transmembrane epithelial mucin glycoprotein, which is aberrantly overexpressed in most adenocarcinomas and is a target for immune therapy for epithelial tumors. Recently, MUC1 has been detected in a variety of hematopoietic cell malignancies including T and B cell lymphomas and myelomas; however, its function in these cells is not clearly defined. Using the Jurkat T cell lymphoma cell line and normal human T cells, we demonstrate that MUC1 is not only expressed in these cells but is also phosphorylated upon T cell receptor (TCR) ligation and associates with the Src-related T cell tyrosine kinase, p56lck. Upon TCR-mediated activation of Jurkat cells, MUC1 is found in the low-density membrane fractions, where linker of T cell activation is contained. Abrogation of MUC1 expression in Jurkat cells by MUC1-specific small interfering RNA resulted in defects in TCR-mediated downstream signaling events associated with T cell activation. These include reduction in Ca2+ influx and extracellular signal-regulated kinase 1/2 phosphorylation, leading to a decrease in CD69 expression, proliferation, and interleukin-2 production. These results suggest a regulatory role of MUC1 in modulating proximal signal transduction events through its interaction with proteins of the activation complex.

Dominant role of antigen dose in CD4+Foxp3+ regulatory T cell induction and expansion1

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Turner, Michael S.; Kane, Lawrence P.; Morel, Penelope A.

2009-01-01

The definitions of tolerogenic vs. immunogenic dendritic cells (DC) remain controversial. Immature DC have been shown to induce T regulatory cells (Treg) specific for foreign and allo-antigens. However, we have previously reported that mature DC (G4DC) prevented the onset of autoimmune diabetes whereas immature DC (GMDC) were therapeutically ineffective. In this study, islet-specific CD4+ T cells from BDC2.5 TCR Tg mice were stimulated, in the absence of exogenous cytokine, with GMDC or G4DC pulsed with high- or low-affinity antigenic peptides and examined for Treg induction. Both GMDC and G4DC presenting low peptide doses induced weak TCR signaling via the Akt/mTOR pathway, resulting in significant expansion of Foxp3+ Treg. Furthermore, unpulsed G4DC, but not GMDC, also induced Treg. High peptide doses induced strong Akt/mTOR signaling and favored the expansion of Foxp3neg Th cells. The inverse correlation of Foxp3 and Akt/mTOR signaling was also observed in DO11.10 and OT-II TCR-Tg T cells and was recapitulated with anti-CD3/CD28 stimulation in the absence of DC. IL-6 production in these cultures correlated positively with antigen dose and inversely with Treg expansion. Studies with T cells or DC from IL-6−/− mice revealed that IL-6 production by T cells was more important in the inhibition of Treg induction at low antigen doses. These studies indicate that strength of Akt/mTOR signaling, a critical T cell intrinsic determinant for Treg vs Th induction, can be controlled by adjusting the dose of antigenic peptide. Furthermore, this operates in a dominant fashion over DC phenotype and cytokine production. PMID:19801514

Upregulation of CD200 is associated with Foxp3+ regulatory T cell expansion and disease progression in acute myeloid leukemia.

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Memarian, Ali; Nourizadeh, Maryam; Masoumi, Farimah; Tabrizi, Mina; Emami, Amir Hossein; Alimoghaddam, Kamran; Hadjati, Jamshid; Mirahmadian, Mahroo; Jeddi-Tehrani, Mahmood

2013-02-01

Immunosuppression in acute myeloid leukemia (AML) is an important mechanism of tumor escape. CD200, as an immunosuppressive molecule, is overexpressed in some hematological malignancies and it has also been shown to be an independent prognostic factor in AML. In the current study, simultaneous CD200 expression and Foxp3(+) regulatory T cell levels were investigated in Iranian patients with AML by flow cytometry. We also assessed the effect of CD200-CD200R blockade on Th1 and T-reg cytokine production and T cell proliferation in autologous AML- and monocyte-DC mixed lymphocyte reactions (MLRs). ELISA assay was performed to detect IL-2, IL-12, IFN-γ, IL-10, and TGF-β production in MLR supernatants. Expression of Foxp3, IL-10, and TGF-β mRNAs in MLRs were detected by real-time PCR. Our results demonstrated significant overexpression of CD200 (P = 0.001) in association with higher frequencies of Foxp3(+) T cells in AML patients (r = 0.8, P T cell levels with lower Foxp3 intensity was also shown in CD200-CD200R-blocked MLRs. Expression of IL-10 mRNA declined significantly only in AML-DC MLRs where CD200-CD200R interaction was blocked and the same result was observed for TGF-β and Foxp3 mRNA in both AML- and monocyte-DC MLRs. These data present a significant role for CD200 in suppressing anti-tumor immune response through stimulation of regulatory mechanisms in AML patients and suggest that CD200 may have a prognostic value in this malignancy and its blockade may be used as a target for AML immunotherapy.

Interleukin 4 promotes the development of ex-Foxp3 Th2 cells during immunity to intestinal helminths

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Coomes, Stephanie M.; Kannan, Yashaswini; Entwistle, Lewis J.; Perez-Lloret, Jimena; Czieso, Stephanie

2017-01-01

Immunity to intestinal helminth infections requires the rapid activation of T helper 2 cells (Th2 cells). However, simultaneous expansion of CD4+Foxp3+ regulatory T cells (T reg cells) impedes protective responses, resulting in chronic infections. The ratio between T reg and effector T cells can therefore determine the outcome of infection. The redifferentiation of T reg cells into Th cells has been identified in hyperinflammatory diseases. In this study, we asked whether ex–T reg Th2 cells develop and contribute to type-2 immunity. Using multigene reporter and fate-reporter systems, we demonstrate that a significant proportion of Th2 cells derive from Foxp3+ cells after Heligmosomoides polygyrus infection and airway allergy. Ex-Foxp3 Th2 cells exhibit characteristic Th2 effector functions and provide immunity to H. polygyrus. Through selective deletion of Il4ra on Foxp3+ cells, we further demonstrate IL-4 is required for the development of ex-Foxp3 Th2 cells. Collectively, our findings indicate that converting T reg cells into Th2 cells could concomitantly enhance Th2 cells and limit T reg cell–mediated suppression. PMID:28507062

Effect of everolimus initiation and early calcineurin inhibitor withdrawal on myocardial FOXP3+ regulatory T cells in heart transplantation

DEFF Research Database (Denmark)

Mirza, Kiran; Gustafsson, Finn; Gullestad, Lars

2016-01-01

BACKGROUND: Through immunosuppression CD4+FoxP3+ regulatory T-cells (Tregs) play an indispensable role in allograft rejection. Post-HTx treatment with everolimus is associated with slower progression of cardiac allograft vasculopathy (CAV) - chronic rejection - than CNI based therapy. We hypothes......BACKGROUND: Through immunosuppression CD4+FoxP3+ regulatory T-cells (Tregs) play an indispensable role in allograft rejection. Post-HTx treatment with everolimus is associated with slower progression of cardiac allograft vasculopathy (CAV) - chronic rejection - than CNI based therapy. We...... hypothesized treatment with everolimus reduced the risk of CAV by modulating myocardial FoxP3 levels. METHODS: 15 patients from the Schedule trial comparing everolimus, MMF, steroid and early CNI (Everolimus, n=8) withdrawal to conventional CNI based immunosuppression (Controls, n=7) after de novo HTx were...

Low-dose temozolomide before dendritic-cell vaccination reduces (specifically) CD4+CD25++Foxp3+ regulatory T-cells in advanced melanoma patients.

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Ridolfi, Laura; Petrini, Massimiliano; Granato, Anna Maria; Gentilcore, Giusy; Simeone, Ester; Ascierto, Paolo Antonio; Pancisi, Elena; Ancarani, Valentina; Fiammenghi, Laura; Guidoboni, Massimo; de Rosa, Francesco; Valmorri, Linda; Scarpi, Emanuela; Nicoletti, Stefania Vittoria Luisa; Baravelli, Stefano; Riccobon, Angela; Ridolfi, Ruggero

2013-05-31

In cancer immunotherapy, dendritic cells (DCs) play a fundamental role in the dialog between innate and adaptive immune response, but several immunosuppressive mechanisms remain to be overcome. For example, a high number of CD4+CD25++Foxp3+ regulatory T-cells (Foxp3+Tregs) have been observed in the peripheral blood and tumor microenvironment of cancer patients. On the basis of this, we conducted a study on DC-based vaccination in advanced melanoma, adding low-dose temozolomide to obtain lymphodepletion. Twenty-one patients were entered onto our vaccination protocol using autologous DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin. Patients received low-dose temozolomide before vaccination and 5 days of low-dose interleukin-2 (IL-2) after vaccination. Circulating Foxp3+Tregs were evaluated before and after temozolomide, and after IL-2. Among the 17 evaluable patients we observed 1 partial response (PR), 6 stable disease (SD) and 10 progressive disease (PD). The disease control rate (PR+SD = DCR) was 41% and median overall survival was 10 months. Temozolomide reduced circulating Foxp3+Treg cells in all patients. A statistically significant reduction of 60% was observed in Foxp3+Tregs after the first cycle, whereas the absolute lymphocyte count decreased by only 14%. Conversely, IL-2 increased Foxp3+Treg cell count by 75.4%. Of note the effect of this cytokine, albeit not statistically significant, on the DCR subgroup led to a further 33.8% reduction in Foxp3+Treg cells. Our results suggest that the combined immunological therapy, at least as far as the DCR subgroup is concerned, effectively reduced the number of Foxp3+Treg cells, which exerted a blunting effect on the growth-stimulating effect of IL-2. However, this regimen, with its current modality, would not seem to be capable of improving clinical outcome.

The Living Eye “Disarms” Uncommitted Autoreactive T Cells by Converting Them to FoxP3+ Regulatory Cells Following Local Antigen Recognition

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Zhou, Ru; Horai, Reiko; Silver, Phyllis B; Mattapallil, Mary J; Zárate-Bladés, Carlos R; Chong, Wai Po; Chen, Jun; Rigden, Rachael C; Villasmil, Rafael; Caspi, Rachel R

2011-01-01

Immune privilege is used by the eye, brain, reproductive organs and gut to preserve structural and functional integrity in the face of inflammation. The eye is arguably the most vulnerable, and therefore also the most “privileged” of tissues, but paradoxically, remains subject to destructive autoimmunity. It has been proposed, although never proven in vivo, that the eye can induce T regulatory cells (Tregs) locally. Using FoxP3-GFP reporter mice expressing a retina-specific T cell receptor, we now show that uncommitted T cells rapidly convert in the living eye to FoxP3+ Tregs in a process involving retinal antigen recognition, de novo FoxP3 induction and proliferation. This takes place within the ocular tissue and is supported by retinoic acid, which is normally present in the eye due to its function in the chemistry of vision. Non-converted T cells showed evidence of priming, but appeared restricted from expressing effector function in the eye. Preexisting ocular inflammation impeded conversion of uncommitted T cells into Tregs. Importantly, retina-specific T cells primed in vivo before introduction into the eye were resistant to Treg conversion in the ocular environment, and instead caused severe uveitis. Thus, uncommitted T cells can be disarmed, but immune privilege is unable to protect from uveitogenic T cells that have acquired effector function prior to entering the eye. These findings shed new light on the phenomenon of immune privilege and on its role, as well as its limitations, in actively controlling immune responses in the tissue. PMID:22238462

[Changes of CD(4)(+)Foxp3(+) regulatory T cells and CD(4)(+)IL-17(+)T cells in cigarette smoke-exposed rats].

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Meng, Jing-jing; Zhong, Xiao-ning; Bai, Jing; He, Zhi-yi; Zhang, Jian-quan; Huang, Qiu-pin

2012-01-01

To evaluate the changes of CD(4)(+)IL-17(+) T (Th17) and CD(4)(+)Foxp3(+) regulatory T (Treg) cells in peripheral blood and bronchoalveolar lavage fluid (BALF), and therefore to explore the role of Th17 and Treg in cigarette smoke-induced airway inflammation/COPD in rats. Forty male Wistar rats were randomly divided into 4 groups: a 12 wk smoke-exposure group, a 24 wk smoke-exposure group, a 12 wk control group and a 24 wk control group (n = 10 each). Cells in BALF were collected and analyzed by absolute and differential cell counts. IL-17 and IL-6 levels in serum and BALF were tested by enzyme linked immunosorbent assay (ELISA). The proportion of CD(4)(+)IL-17(+) T and CD(4)(+)Foxp3(+) Treg in peripheral blood and BALF were determined by flow cytometry. The mRNA expressions of IL-17 and Foxp3 were measured by real-time PCR. Comparisons of the data between different groups were performed using one-way ANOVA, and SNK and Games-Howell test were used for comparison between 2 groups. Levels of IL-17 were remarkable increased in the 12 wk smoke-exposure group and the 24 wk smoke-exposure group in serum [(52.6 ± 1.8) ng/L, (75.4 ± 6.0) ng/L] and BALF [(78.1 ± 5.8) ng/L, (95.0 ± 6.8) ng/L] compared with the 12 wk control group [(40.0 ± 3.2)ng/L, (54.5 ± 4.6) ng/L] and the 24 wk control group [(36.7 ± 3.2) ng/L, (53.9 ± 3.7) ng/L], all P cells and macrophages (r = 0.512, 0.543, all P cells and an increase of inflammatory cytokines were evident in airway inflammation of cigarette smoke-exposed rats, suggesting that Treg was involved in the immunological regulation and Th17 was associated with the persistent inflammation in cigarette smoke-induced airway inflammation in rats.

Influence of zinc deficiency on cell-membrane fluidity in Jurkat, 3T3 and IMR-32 cells.

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Verstraeten, Sandra V; Zago, M Paola; MacKenzie, Gerardo G; Keen, Carl L; Oteiza, Patricia I

2004-01-01

We investigated whether zinc deficiency can affect plasma membrane rheology. Three cell lines, human leukaemia T-cells (Jurkat), rat fibroblasts (3T3) and human neuroblastoma cells (IMR-32), were cultured for 48 h in control medium, in zinc-deficient medium (1.5 microM zinc; 1.5 Zn), or in the zinc-deficient medium supplemented with 15 microM zinc (15 Zn). The number of viable cells was lower in the 1.5 Zn group than in the control and 15 Zn groups. The frequency of apoptosis was higher in the 1.5 Zn group than in the control and 15 Zn groups. Membrane fluidity was evaluated using the 6-(9-anthroyloxy)stearic acid and 16-(9-anthroyloxy)palmitic acid probes. Membrane fluidity was higher in 1.5 Zn cells than in the control cells; no differences were observed between control cells and 15 Zn cells. The effect of zinc deficiency on membrane fluidity at the water/lipid interface was associated with a higher phosphatidylserine externalization. The higher membrane fluidity in the hydrophobic region of the bilayer was correlated with a lower content of arachidonic acid. We suggest that the increased fluidity of the membrane secondary to zinc deficiency is in part due to a decrease in arachidonic acid content and the apoptosis-related changes in phosphatidylserine distribution. PMID:14629198

Transgene IL-6 Enhances DC-Stimulated CTL Responses by Counteracting CD4+25+Foxp3+ Regulatory T Cell Suppression via IL-6-Induced Foxp3 Downregulation

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Kalpana Kalyanasundaram Bhanumathy

2014-03-01

Full Text Available Dendritic cells (DCs, the most potent antigen-presenting cells have been extensively applied in clinical trials for evaluation of antitumor immunity. However, the efficacy of DC-mediated cancer vaccines is still limited as they are unable to sufficiently break the immune tolerance. In this study, we constructed a recombinant adenoviral vector (AdVIL-6 expressing IL-6, and generated IL-6 transgene-engineered DC vaccine (DCOVA/IL-6 by transfection of murine bone marrow-derived ovalbumin (OVA-pulsed DCs (DCOVA with AdVIL-6. We then assessed DCOVA/IL-6-stimulated cytotoxic T-lymphocyte (CTL responses and antitumor immunity in OVA-specific animal tumor model. We demonstrate that DCOVA/IL-6 vaccine up-regulates expression of DC maturation markers, secretes transgene-encoded IL-6, and more efficiently stimulates OVA-specific CTL responses and therapeutic immunity against OVA-expressing B16 melanoma BL6-10OVA in vivo than the control DCOVA/Null vaccine. Moreover, DCOVA/IL-6-stimulated CTL responses were relatively maintained in mice with transfer of CD4+25+Foxp3+ Tr-cells, but significantly reduced when treated with anti-IL-6 antibody. In addition, we demonstrate that IL-6 down-regulates Foxp3-expression of CD4+25+Foxp3+ Tr-cells in vitro. Taken together, our results demonstrate that AdV-mediated IL-6 transgene-engineered DC vaccine stimulates potent CTL responses and antitumor immunity by counteracting CD4+25+ Tr immunosuppression via IL-6-induced Foxp3 down-regulation. Thus, IL-6 may be a good candidate for engineering DCs for cancer immunotherapy.

EFFECTS OF HISTONE DEACETYLASE INHIBITOR, SAHA, ON EFFECTOR AND FOXP3+ REGULATORY T CELLS IN RHESUS MACAQUES

OpenAIRE

Johnson, Jennifer; Pahuja, Anil; Graham, Melanie; Hering, Bernhard; Hancock, Wayne W.; Pratima, Bansal-Pakala

2008-01-01

SAHA, a histone deacetylase inhibitor (HDACi), is clinically approved for treatment of cutaneous T-cell lymphoma. Although the exact underlying mechanisms are unknown, HDACi arrest the cell cycle in rapidly proliferating tumor cells and promote their apoptosis. HDACi were also recently shown to enhance the production and suppressive functions of Foxp3+ regulatory T (Treg) cells in rodents, leading us to begin to investigate the actions of HDACi on rhesus monkey T cells for the sake of potenti...

Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia.

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Janikashvili, Nona; LaCasse, Collin J; Larmonier, Claire; Trad, Malika; Herrell, Amanda; Bustamante, Sara; Bonnotte, Bernard; Har-Noy, Michael; Larmonier, Nicolas; Katsanis, Emmanuel

2011-02-03

Therapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4(+) T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4(+)CD25(+)FoxP3(+) regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3(+) Tregs from naive CD4(+)CD25(-)FoxP3(-) T cells by an interferon-γ-dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with a chaperone-rich cell lysate (CRCL) vaccine, leading to improved survival and long-lasting protection against leukemia. The combination of CRCL as a source of tumor-specific antigens and Th-1 lymphocytes as an adjuvant has the potential to stimulate efficient specific antitumor immunity while restraining Treg-induced suppression.

Increased numbers of Foxp3-positive regulatory T cells in gastritis, peptic ulcer and gastric adenocarcinoma

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Cheng, Hsin-Hung; Tseng, Guan-Ying; Yang, Hsiao-Bai; Wang, Hung-Jung; Lin, Hwai-Jeng; Wang, Wen-Ching

2012-01-01

AIM: To determine the number of regulatory T cells (Tregs) in gastric mucosa of patients with gastritis, peptic ulcers and gastric cancer. METHODS: This study was a retrospective analysis of gastric antrum biopsy specimens from healthy controls (n = 22) and patients with gastritis (n = 30), peptic ulcer (n = 83), or gastric cancer (n = 32). Expression of CD4, CD25 and Foxp3 was determined by immunohistochemistry in three consecutive sections per sample. RESULTS: Compared with healthy controls, there was an increased number of CD25+ and Foxp3+ cells in patients with gastritis (P = 0.004 and P = 0.008), peptic ulcer (P gastritis (P gastritis and peptic ulcer groups. PMID:22228968

Salmon cartilage proteoglycan suppresses mouse experimental colitis through induction of Foxp3+ regulatory T cells

International Nuclear Information System (INIS)

Mitsui, Toshihito; Sashinami, Hiroshi; Sato, Fuyuki; Kijima, Hiroshi; Ishiguro, Yoh; Fukuda, Shinsaku; Yoshihara, Shuichi; Hakamada, Ken-Ichi; Nakane, Akio

2010-01-01

Research highlights: → Salmon proteoglycan suppresses IL-10 -/- cell transfer-induced colitis progression. → Salmon proteoglycan suppresses Th1- and Th17-related factors in colitis mice. → Salmon proteoglycan enhances Foxp3 expression. -- Abstract: Proteoglycans (PGs) are complex glycohydrates which are widely distributed in extracellular matrix (ECM). PGs are involved in the construction of ECM, cell proliferation and differentiation. ECM components are involved in transduction of proinflammatory responses, but it is still unknown whether PGs are involved in inflammatory response. In this study, we investigated the effect of PG extracted from salmon cartilage on the progression of experimental colitis-induced in severe combined immunodeficiency mice by cell transfer from interleukin-10 (IL-10) -/- mice. IL-10 -/- cell-transferred mice showed weight loss, colon shortening and histological appearance of mild colitis. Daily oral administration of PG attenuated the clinical progression of colitis in a dose-dependent manner. Colitis-induced mice showed the elevated expression of IFN-γ, IL-12, TNF-α, IL-21, IL-23p19, IL-6, IL-17A and retinoic acid-related orphan receptor γt (RORγt) in lamina propria mononuclear cells (LPMCs) and oral administration of PG suppressed the expression of these factors. Conversely, expression of Foxp3 that induces CD4 + CD25 + regulatory T cells in LPMCs was enhanced by PG administration. These findings suggested that salmon PG attenuated the progression of colitis due to suppression of inflammatory response by enhancement of regulatory T cell induction.

[Changes of CD(4)(+) Foxp3+ regulatory T cells and CD(4)(+)IL-17+T cells in acrolein exposure rats].

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Wei, Ming; Tu, Ling; Liang, Yinghong; Li, Jia; Gong, Yanjie; Zhang, Yihua; Yang, Lu

2015-09-01

To evaluate the changes of CD(4)(+) IL-17+T (Th17) and CD(4)(+)Foxp3+regulatory T (Treg) cells in peripheral blood and bronchoalveolar lavage fluid (BALF) , and therefore to explore the role of Th17 and Treg in acrolein exposure airway inflammation in rats. Forty male Wistar rats were randomly divided into 4 groups: a 2 wk acrolein exposure group, a 4 wk acrolein exposure group, a 2 wk control group and a 4 wk control group (n=10 each). Cells in BALF were collected and analyzed by absolute and differential cell counts.IL-17 and IL-6 levels in serum and BALF were tested by enzyme linked immunosorbent assay (ELISA). The proportion of CD(4)(+)IL-17+T and CD(4)(+) Foxp3+Treg in peripheral blood and BALF were determined by flow cytometry.The mRNA expressions of IL-17 and Foxp3 were measured by real-time PCR. Comparisons of the data between different groups were performed using one-way ANOVA, and SNK and Games-Howell test were used for comparison between 2 groups. Levels of IL-17 were remarkable increased in the 2 wk acrolein exposure group and the 4 wk acrolein exposure group in serum [(52.64 ± 1.89) ng/L, (76.73 ± 5.57) ng/L], and BALF [(79.07 ± 5.67) ng/L, (96.61 ± 6.44) ng/L] compared with the 2 wk control group [(40.05 ± 3.12) ng/L, (56.75 ± 4.37) ng/L] and the 4 wk control group [(38.75 ± 3.23) ng/L, (53.27 ± 4.48) ng/L], all Pcells and macrophages (r=0.5126, 0.5437, all Pcells and an vary of inflammatory cytokines were evident in airway inflammation of acrolein exposed rats, suggesting that Treg was involved in the immunological regulation and Th17 was associated with the persistent inflammation in acrolein induced airway inflammation in rats.

CD4~+Foxp3~+ regulatory T cells converted by rapamycin from peripheral CD4~+ CD25~-naive T cells display more potent regulatory ability in vitro

Institute of Scientific and Technical Information of China (English)

CHEN Jian-fei; GAO Jie; ZHANG Dong; WANG Zi-han; ZHU Ji-ye

2010-01-01

Background Rapamycin (RAPA) is a relatively new immunosuppressant drug that functions as a serine/threonine kinase inhibitor to prevent rejection in organ transplantation. RAPA blocks activation of T-effector (Teff) cells by inhibiting the response to interleukin-2. Recently, RAPA was also shown to selectively expand the T-regulator (Treg) cell population. To date, no studies have examined the mechanism by which RAPA converts Teff cells to Treg cells. Methods Peripheral CD4~+CD25~- naive T cells were cultivated with RAPA and B cells as antigen-presenting cells (APCs) in vitro. CD4~+CD25~- T cells were harvested after 6 days and analyzed for expression of forkhead box protein 3 (Foxp3) using flow cytometry. CD4~+CD25~+CD127~- subsets as the converted Tregs were isolated from the mixed lymphocyte reactions (MLR) with CD127 negative selection, followed by CD4 and CD25 positive selection using microbeads and magnetic separation column (MSC). Moreover, mRNA was extracted from converted Tregs and C57BL/6 naive CD4~+CD25~+ T cells and Foxp3 levels were examined by quantitative real-time polymerase chain reaction (rt-PCR). A total of 1×10~5 carboxyfluorescein succinimidyl ester (CFSE)-labeled naive CD4~+CD25~- T cells/well from C57BL/6 mice were cocultured with DBA/2 or C3H maturation of dendritic cells (mDCs) (0.25×10~5/well) in 96-well round-bottom plates for 6 days. Then 1×10~5 or 0.25×10~5 converted Treg cells were added to every well as regulatory cells. Cells were harvested after 6 days of culture and analyzed for proliferation of CFSE-labeled naive CD4~+CD25~- T cells using flow cytometry. Data were analyzed using CellQuest software.Results We found that RAPA can convert peripheral CD4~+CD25~- naive T Cells to CD4~+Foxp3~+ Treg cells using B cells as APCs, and this subtype of Treg can potently suppress Teff proliferation and maintain antigenic specificity. Conclusion Our findings provide evidence that RAPA induces Treg cell conversion from Teff cells and

CD4+ and Perivascular Foxp3+ T Cells in Glioma Correlate with Angiogenesis and Tumor Progression

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Luyan Mu

2017-11-01

Full Text Available BackgroundAngiogenesis and immune cell infiltration are key features of gliomas and their manipulation of the microenvironment, but their prognostic significance remains indeterminate. We evaluate the interconnection between tumor-infiltrating lymphocyte (TIL and tumor blood-vasculatures in the context of glioma progression.MethodsPaired tumor tissues of 44 patients from three tumor-recurrent groups: diffuse astrocytomas (DA recurred as DA, DA recurred as glioblastomas (GBM, and GBM recurred as GBM were evaluated by genetic analysis, immunohistochemistry for tumor blood vessel density, TIL subsets, and clinical outcomes. These cells were geographically divided into perivascular and intratumoral TILs. Associations were examined between these TILs, CD34+ tumor blood vessels, and clinical outcomes. To determine key changes in TIL subsets, microarray data of 15-paired tumors from patients who failed antiangiogenic therapy- bevacizumab, and 16-paired tumors from chemo-naïve recurrent GBM were also evaluated and compared.ResultsUpon recurrence in primary gliomas, similar kinetic changes were found between tumor blood vessels and each TIL subset in all groups, but only CD4+ including Foxp3+ TILs, positively correlated with the density of tumor blood vessels. CD4 was the predominant T cell population based on the expression of gene-transcripts in primary GBMs, and increased activated CD4+ T cells were revealed in Bevacizumab-resistant recurrent tumors (not in chemo-naïve recurrent tumors. Among these TILs, 2/3 of them were found in the perivascular niche; Foxp3+ T cells in these niches not only correlated with the tumor vessels but were also an independent predictor of shortened recurrence-free survival (RFS (HR = 4.199, 95% CI 1.522–11.584, p = 0.006.ConclusionThe minimal intratumoral T cell infiltration and low detection of CD8 transcripts expression in primary GBMs can potentially limit antitumor response. CD4+ and perivascular Foxp3

Damage of Neuroblastoma Cell SH-SY5Y Mediated by MPP+ Inhibits Proliferation of T-Cell Leukemia Jurkat by Co-Culture System

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Fuli Wang

2014-06-01

Full Text Available The adaptive immune system has implications in pathology of Parkinson’s disease (PD. Research data demonstrated that the peripheral CD4+ T-cell population decreased in pathogenesis of PD. The effect of damaged dopaminergic neurons on peripheral T cells of PD is still unknown. In this study, we constructed a neuronal and glial cells co-culture model by using human neuroblastoma cells SH-SY5Y and gliomas cells U87. After the co-culture cells were treated with neurotoxin 1-methyl-4-phenylpyridinium (MPP+ for 24 h, the conditioned media was harvested and used to cultivate T-cell leukemia Jurkat cells for another 24 h. We then analyzed the cell proliferation, cell cycle and necrosis effect of Jurkat cells. The results showed that co-culture medium of SH-SY5Y and U87 cells with MPP+ treatment inhibited the proliferation of Jurkat cells compared to control medium without MPP+, even though the same concentration of MPP+ had very little toxicity to the Jurkat cell. Furthermore, co-culture medium with low concentration of MPP+ (100 µM arrested Jurkat cells cycle in G2/M phase through increasing cell cycle division 2 (CDC2 and CyclinB1 expression level, whereas co-culture medium with high concentration of MPP+ (500 µM induced Jurkat cell necrosis through cellular swelling and membrane breakage. Our data implies that damaged dopamine neurons with glial cells can lead to the reduced number or inhibited proliferation activity of peripheral T cells.

CD4+ FOXP3+ Regulatory T Cells Exhibit Impaired Ability to Suppress Effector T Cell Proliferation in Patients with Turner Syndrome.

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Young Ah Lee

Full Text Available We investigated whether the frequency, phenotype, and suppressive function of CD4+ FOXP3+ regulatory T cells (Tregs are altered in young TS patients with the 45,X karyotype compared to age-matched controls.Peripheral blood mononuclear cells from young TS patients (n = 24, 17.4-35.9 years and healthy controls (n = 16 were stained with various Treg markers to characterize their phenotypes. Based on the presence of thyroid autoimmunity, patients were categorized into TS (- (n = 7 and TS (+ (n = 17. Tregs sorted for CD4+ CD25bright were co-cultured with autologous CD4+ CD25- target cells in the presence of anti-CD3 and -CD28 antibodies to assess their suppressive function.Despite a lower frequency of CD4+ T cells in the TS (- and TS (+ patients (mean 30.8% and 31.7%, vs. 41.2%; P = 0.003 and P < 0.001, respectively, both groups exhibited a higher frequency of FOXP3+ Tregs among CD4+ T cells compared with controls (means 1.99% and 2.05%, vs. 1.33%; P = 0.029 and P = 0.004, respectively. There were no differences in the expression of CTLA-4 and the frequency of Tregs expressing CXCR3+, and CCR4+ CCR6+ among the three groups. However, the ability of Tregs to suppress the in vitro proliferation of autologous CD4+ CD25- T cells was significantly impaired in the TS (- and TS (+ patients compared to controls (P = 0.003 and P = 0.041. Meanwhile, both the TS (- and TS (+ groups had lower frequencies of naïve cells (P = 0.001 for both but higher frequencies of effector memory cells (P = 0.004 and P = 0.002 than did the healthy control group.The Tregs of the TS patients could not efficiently suppress the proliferation of autologous effector T cells, despite their increased frequency in peripheral CD4+ T cells.

Absence of Foxp3+ regulatory T cells during allergen provocation does not exacerbate murine allergic airway inflammation.

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Abdul Mannan Baru

Full Text Available Regulatory T cells (Tregs play a non-redundant role in maintenance of immune homeostasis. This is achieved by suppressing both, priming of naïve cells and effector cell functions. Although Tregs have been implicated in modulating allergic immune responses, their influence on distinct phases of development of allergies remains unclear. In this study, by using bacterial artificial chromosome (BAC-transgenic Foxp3-DTR (DEREG mice we demonstrate that the absence of Foxp3(+ Tregs during the allergen challenge surprisingly does not exacerbate allergic airway inflammation in BALB/c mice. As genetic disposition due to strain specificity may contribute significantly to development of allergies, we performed similar experiment in C57BL/6 mice, which are less susceptible to allergy in the model of sensitization used in this study. We report that the genetic background does not influence the consequence of this depletion regimen. These results signify the temporal regulation exerted by Foxp3(+ Tregs in limiting allergic airway inflammation and may influence their application as potential therapeutics.

Lactobacillus reuteri DSM 17938 changes the frequency of Foxp3+ regulatory T cells in the intestine and mesenteric lymph node in experimental necrotizing enterocolitis.

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Yuying Liu

Full Text Available Necrotizing enterocolitis (NEC is an inflammatory disease of the intestine in premature infants. Lactobacillus reuteri DSM 17938 improves survival and reduces the incidence and severity of NEC in a rodent model. Foxp3(+ regulatory T cells (Tregs maintain intestinal homeostasis by controlling inflammation and inducing tolerance. To determine whether there are insufficient numbers of Tregs to control inflammation in NEC and to determine if LR17938 increases the frequency of Tregs, we studied selected groups of newborn Sprague-Dawley rats according to feeding plan: dam±LR17938, formula±LR17938, and NEC±LR17938. NEC was induced by gavage feeding with special formula and exposure to hypoxic conditions. Lymphocytes isolated from ileum, mesenteric lymph nodes (MLN, spleen and thymus were labeled for T cell surface markers (CD3, CD4, CD8 and intracellular Foxp3; and labeled cells were analyzed by flow cytometry. The percentage of CD3(+ T cells and Foxp3(+ Tregs in the ileum significantly decreased in pups with NEC, compared to normal controls. Feeding LR17938 to neonatal rats with NEC increased the % of Foxp3(+ T cells in the ileum while decreasing the percentage of cells in the MLN. Administration of LR17938 to dam-fed rats significantly increased Foxp3(+Tregs in the ileum as early as day of life (DOL1 but did not produce an increase in Tregs in formula-fed rats on DOL1. These results suggest that factors in breast milk may enhance the early immunomodulatory effects of LR17938. An anti-inflammatory effect of LR17938 in NEC was associated with the modulation of immune responses and induction and what appears to be migration of Foxp3(+ Tregs to the diseased gut. Probiotic-facilitated development of Tregs might play an important role in the prevention of NEC.

Early Increases in Superantigen-Specific Foxp3+ Regulatory T Cells during Mouse Mammary Tumor Virus Infection▿ †

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Cabrera, Gabriel; Burzyn, Dalia; Mundiñano, Juliana; Courreges, M. Cecilia; Camicia, Gabriela; Lorenzo, Daniela; Costa, Héctor; Ross, Susan R.; Nepomnaschy, Irene; Piazzon, Isabel

2008-01-01

Mouse mammary tumor virus (MMTV) is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. Here, we show in a natural model of MMTV infection that the virus causes early and progressive increases in superantigen (SAg)-specific Foxp3+ regulatory T cells (Treg) in Peyer's patches (PP). These increases were shown to be dependent on the presence of dendritic cells. CD4+ CD25+ T cells from the PP of infected mice preferentially suppress the proliferative response of T cells to SAg-expressing antigen-presenting cells ex vivo. We investigated the influence of the depletion of CD25+ cells at different stages of the infection. When CD25+ cells were depleted before MMTV infection, an increase in the number of PP SAg-cognate Foxp3− T cells was found at day 6 of infection. Since the SAg response is associated with viral amplification, the possibility exists that Treg cells attenuate the increase in viral load at the beginning of the infection. In contrast, depletion of CD25+ cells once the initial SAg response has developed caused a lower viral load, suggesting that at later stages Treg cells may favor viral persistence. Thus, our results indicated that Treg cells play an important and complex role during MMTV infection. PMID:18495774

Protein Arginine Methyltransferase 5 Inhibition Upregulates Foxp3+ Regulatory T Cells Frequency and Function during the Ulcerative Colitis

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Yingxia Zheng

2017-05-01

Full Text Available Ulcerative colitis (UC pathogenesis is related to imbalance of immune responses, and the equilibrium between inflammatory T cells and Foxp3+ regulatory T cells (Tregs plays an important role in the intestinal homeostasis. Protein arginine methyltransferases (PRMTs regulate chromatin remodeling and gene expression. Here, we investigated whether inhibition of PRMTs affects colitis pathogenesis in mice and inflammatory bowel disease patients and further explored the underlying mechanisms. In this study, we found that protein arginine N-methyltransferase inhibitor 1 (AMI-1 treatments increased Tregs frequency, function, and reduced colitis incidence. Adoptive transfer of AMI-1-treated Tregs could reduce the colitis incidence. Colitis was associated with increased local PRMT5 expression, which was inhibited by AMI-1 treatment. Additionally, PRMT5 knockdown T cells produced a better response to TGFβ and promoted Tregs differentiation through decreased DNA methyltransferase 1 (DNMT1 expression. PRMT5 also enhanced H3K27me3 and DNMT1 binding to Foxp3 promoter, which restricted Tregs differentiation. Furthermore, PRMT5 knockdown led to decreased Foxp3 promoter methylation during Tregs induction. PRMT5 expression had a negative relationship with Tregs in UC patients, knockdown of PRMT5 expression increased Tregs frequency and decreased TNFα, IL-6, and IL-13 levels. Our study outlines a novel regulation of PRMT5 on Tregs development and function. Strategies to decrease PRMT5 expression might have therapeutic potential to control UC.

CD4+CD25hiFOXP3+ cells in cord blood of neonates born from filaria infected mother are negatively associated with CD4+Tbet+ and CD4+RORγt+ T cells.

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Ateba-Ngoa, Ulysse; Mombo-Ngoma, Ghyslain; Zettlmeissl, Eva; van der Vlugt, Luciën E P M; de Jong, Sanne E; de Jong, Sanne; Matsiegui, Pierre-Blaise; Ramharter, Michael; Kremsner, Peter G; Yazdanbakhsh, Maria; Adegnika, Ayola Akim

2014-01-01

Children who have been exposed in utero to maternal filarial infection are immunologically less responsive to filarial antigens, have less pathology, and are more susceptible to acquire infection than offspring of uninfected mothers. Moreover children from filaria infected mothers have been shown to be less responsive to vaccination as a consequence of an impairment of their immune response. However, it is not well known how in utero exposure to parasite antigens affects cellular immune responses. Here, 30 pregnant women were examined for the presence of microfilaria of Loa loa and Mansonella perstans in peripheral blood. At delivery, cord blood mononuclear cells (CBMC) were obtained and the CD4+T cells were phenotyped by expression of the transcription factors Tbet, RORγt, and FOXP3. No significant difference was observed between newborns from infected versus uninfected mothers in the frequencies of total CD4+T cells and CD4+T cells subsets including CD4+Tbet+, CD4+RORγt+ T and CD4+CD25hiFOXP3+ T cells. However, there was a negative association between CD4+CD25hiFOXP3+T cells and CD4+Tbet+ as well as CD4+RORγt+ T cells in the infected group only (B = -0.242, P = 0.002; B = -0.178, P = 0.013 respectively). Our results suggest that filarial infection during pregnancy leads to an expansion of functionally active regulatory T cells that keep TH1 and TH17 in check.

Evaluation of CD4+ CD25+ FoxP3+ regulatory T cells during treatment of patients with brucellosis.

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Hasanjani Roushan, M R; Bayani, M; Soleimani Amiri, S; Mohammadnia-Afrouzi, M; Nouri, H R; Ebrahimpour, S

2016-01-01

Cell-mediated immunity (CMI) plays a critical role in the control of brucellosis. Regulatory T cells (Tregs) have a functional character in modulating the balance between host immune response and tolerance, which can eventually lead to chronic infection or relapse. The aim of this study was to assess the alteration of Tregs in cases of brucellosis before and after treatment. Thirty cases of acute brucellosis with the mean age of 41.03±15.15 years (case group) and 30 healthy persons with the mean age of 40.63±13.95 years (control group) were selected and assessed. Peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood of all individuals. We analyzed the alteration of Treg cell count using flow cytometry for CD4, CD25, and FoxP3 markers. The level of CD4+ CD25+ FoxP3+ Treg cells was increased in active patients compared with controls (2.5±0.99% vs 1.6±0.84%, p= 0.0004), but it had declined in the treated cases (1.83±0.73%, p=0.02). The level of Tregs was elevated in three relapsed cases. The frequency of Tregs and Treg/Teff (effector T cell) ratio was correlated with inverse serum agglutination test (SAT) and, 2-mercaptoethanol (2-ME) titers as markers of treatment in brucellosis. Based on our findings, we suggest that regulatory cells, such as CD4+ CD25+ FoxP3+ Treg cells, may contribute to the development of infection processes involving immune responses in brucellosis, and evaluation of regulatory T-cell levels may be a potential diagnostic strategy for the treatment outcome in chronic and relapsed cases of brucellosis.

Salmon cartilage proteoglycan suppresses mouse experimental colitis through induction of Foxp3{sup +} regulatory T cells

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Mitsui, Toshihito [Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, Zaifu-cho 5, Hirosaki, Aomori 036-8562 (Japan); Department of Digestive Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562 (Japan); Sashinami, Hiroshi [Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, Zaifu-cho 5, Hirosaki, Aomori 036-8562 (Japan); Sato, Fuyuki; Kijima, Hiroshi [Department of Pathology and Bioscience, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562 (Japan); Ishiguro, Yoh; Fukuda, Shinsaku [Department of Digestive Internal Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562 (Japan); Yoshihara, Shuichi [Department of Glycomedicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562 (Japan); Hakamada, Ken-Ichi [Department of Digestive Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562 (Japan); Nakane, Akio, E-mail: a27k03n0@cc.hirosaki-u.ac.jp [Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, Zaifu-cho 5, Hirosaki, Aomori 036-8562 (Japan)

2010-11-12

Research highlights: {yields} Salmon proteoglycan suppresses IL-10{sup -/-} cell transfer-induced colitis progression. {yields} Salmon proteoglycan suppresses Th1- and Th17-related factors in colitis mice. {yields} Salmon proteoglycan enhances Foxp3 expression. -- Abstract: Proteoglycans (PGs) are complex glycohydrates which are widely distributed in extracellular matrix (ECM). PGs are involved in the construction of ECM, cell proliferation and differentiation. ECM components are involved in transduction of proinflammatory responses, but it is still unknown whether PGs are involved in inflammatory response. In this study, we investigated the effect of PG extracted from salmon cartilage on the progression of experimental colitis-induced in severe combined immunodeficiency mice by cell transfer from interleukin-10 (IL-10){sup -/-} mice. IL-10{sup -/-} cell-transferred mice showed weight loss, colon shortening and histological appearance of mild colitis. Daily oral administration of PG attenuated the clinical progression of colitis in a dose-dependent manner. Colitis-induced mice showed the elevated expression of IFN-{gamma}, IL-12, TNF-{alpha}, IL-21, IL-23p19, IL-6, IL-17A and retinoic acid-related orphan receptor {gamma}t (ROR{gamma}t) in lamina propria mononuclear cells (LPMCs) and oral administration of PG suppressed the expression of these factors. Conversely, expression of Foxp3 that induces CD4{sup +}CD25{sup +} regulatory T cells in LPMCs was enhanced by PG administration. These findings suggested that salmon PG attenuated the progression of colitis due to suppression of inflammatory response by enhancement of regulatory T cell induction.

Functional characterization of Foxp3-specific spontaneous immune responses

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Larsen, Susanne Købke; Munir, S; Andersen, Anders Woetmann

2013-01-01

Tumor-infiltrating CD4+CD25+ regulatory T cells (Tregs) are associated with an impaired prognosis in several cancers. The transcription factor forkhead box P3 (Foxp3) is generally expressed in Tregs. Here, we identify and characterize spontaneous cytotoxic immune responses to Foxp3-expressing cel....... Consequently, induction of Foxp3-specific cytotoxic T-cell responses appears as an attractive tool to boost spontaneous or therapeutically provoked immune responses, for example, for the therapy of cancer....

Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

KAUST Repository

Schmidt, Angelika; Marabita, Francesco; Kiani, Narsis A.; Gross, Catharina C.; Johansson, Henrik J.; É liá s, Szabolcs; Rautio, Sini; Eriksson, Matilda; Fernandes, Sunjay Jude; Silberberg, Gilad; Ullah, Ubaid; Bhatia, Urvashi; Lä hdesmä ki, Harri; Lehtiö , Janne; Gomez-Cabrero, David; Wiendl, Heinz; Lahesmaa, Riitta; Tegner, Jesper

2018-01-01

BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest

Foxp3+ regulatory T cells control persistence of viral CNS infection.

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Dajana Reuter

Full Text Available We earlier established a model of a persistent viral CNS infection using two week old immunologically normal (genetically unmodified mice and recombinant measles virus (MV. Using this model infection we investigated the role of regulatory T cells (Tregs as regulators of the immune response in the brain, and assessed whether the persistent CNS infection can be modulated by manipulation of Tregs in the periphery. CD4(+ CD25(+ Foxp3(+ Tregs were expanded or depleted during the persistent phase of the CNS infection, and the consequences for the virus-specific immune response and the extent of persistent infection were analyzed. Virus-specific CD8(+ T cells predominantly recognising the H-2D(b-presented viral hemagglutinin epitope MV-H(22-30 (RIVINREHL were quantified in the brain by pentamer staining. Expansion of Tregs after intraperitoneal (i.p. application of the superagonistic anti-CD28 antibody D665 inducing transient immunosuppression caused increased virus replication and spread in the CNS. In contrast, depletion of Tregs using diphtheria toxin (DT in DEREG (depletion of regulatory T cells-mice induced an increase of virus-specific CD8(+ effector T cells in the brain and caused a reduction of the persistent infection. These data indicate that manipulation of Tregs in the periphery can be utilized to regulate virus persistence in the CNS.

EFFECT OF LIPOSOMAL CLODRONATE-DEPENDENT DEPLETION OF PROFESSIONAL ANTIGEN PRESENTING CELLS ON NUMBERS AND PHENOTYPE OF CANINE CD4+CD25+FOXP3+ REGULATORY T CELLS

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Weaver, Kriston F.; Stokes, John V.; Gunnoe, Sagen A.; Follows, Joyce S.; Shafer, Lydia; Ammari, Mais G.; Archer, Todd M.; Thomason, John M.; Mackin, Andrew J.; Pinchuk, Lesya M.

2015-01-01

Regulatory T cells (Tregs) are known to control autoreactivity during and subsequent to the development of the peripheral immune system. Professional antigen presenting cells (APCs), dendritic cells (DCs) and monocytes, have an important role in inducing Tregs. For the first time, this study evaluated proportions and phenotypes of Tregs in canine peripheral blood depleted of professional APCs, utilizing liposomal clodronate (LC) and multicolor flow cytometry analysis. Our results demonstrate that LC exposure promoted short term decreases followed by significant increases in the proportions or absolute numbers of CD4+CD25+FOXP3+ Tregs in dogs. In general, the LC-dependent Treg fluctuations were similar to the changes in the levels of CD14+ monocytes in Walker hounds. However, the proportions of monocytes showed more dramatic changes compared to the proportions of Tregs that were visually unchanged after LC treatment over the study period. At the same time, absolute Treg numbers showed, similarly to the levels of CD14+ monocytes, significant compensatory gains as well as the recovery during the normalization period. We confirm the previous data that CD4+ T cells with the highest CD25 expression were highly enriched for FOXP3. Furthermore, for the first time, we report that CD4+CD25lowFOXP3+ is the major regulatory T cell subset affected by LC exposure. The increases within the lowest CD25 expressers of CD4+FOXP3+ cells together with compensatory gains in the proportion of CD14+ monocytes during compensatory and normalization periods suggest the possible direct or indirect roles of monocytes in active recruitment and generation of Tregs from naïve CD4+ T cells. PMID:25950023

Malignant Tregs express low molecular splice forms of FOXP3 in Sézary syndrome

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Krejsgaard, T; Gjerdrum, L M; Ralfkiaer, E

2008-01-01

Sézary syndrome (SS) is an aggressive variant of cutaneous T-cell lymphoma. During disease progression, immunodeficiency develops; however, the underlying molecular and cellular mechanisms are not fully understood. Here, we study the regulatory T cell (Treg) function and the expression of FOXP3...... in SS. We demonstrate that malignant T cells in 8 of 15 patients stain positive with an anti-FOXP3 antibody. Western blotting analysis shows expression of two low molecular splice forms of FOXP3, but not of wild-type (wt) FOXP3. The malignant T cells produce interleukin-10 and TGF-beta and suppress...... the growth of non-malignant T cells. The Treg phenotype and the production of suppressive cytokines are driven by aberrant activation of Jak3 independent of the FOXP3 splice forms. In contrast to wt FOXP3, the low molecular splice forms of FOXP3 have no inhibitory effect on nuclear factor-kappaB (NF...

Immunohistochemical analysis of FoxP3+ cells in periapical granulomas and radicular cysts.

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Peixoto, Raniel Fernandes; Pereira, Joabe dos Santos; Nonaka, Cassiano Francisco Weege; Silveira, Ericka Janine Dantas da; Miguel, Márcia Cristina da Costa

2012-09-01

To compare the number of FoxP3(+) cells between periapical granulomas (PGs) and radicular cysts (RCs), and to correlate this number with the intensity of the inflammatory infiltrate in these lesions and with epithelial thickness of RCs. Thirty PGs and 30 RCs were submitted to immunohistochemical analysis using an anti-FoxP3 polyclonal antibody. FoxP3(+) cells were counted under a light microscope (×400 magnification) in five fields and the mean value was calculated for each specimen. Statistical tests were used to evaluate differences in the number of FoxP3(+) cells according to type of lesion (PG vs. RC), intensity of the inflammatory infiltrate (grade I/II vs. grade III), and epithelial thickness of RCs (atrophic vs. hyperplastic). FoxP3(+) cells were detected in most PGs (93.3%) and RCs (93.3%). The median number of FoxP3(+) cells was 2.40 in PGs and 1.00 in RCs, with this difference being statistically significant (P=0.005). No significant differences in the number of FoxP3(+) cells were observed in terms of the intensity of the inflammatory infiltrate (P=0.465) or epithelial thickness of RCs (P=0.737). The present results suggest a greater participation of regulatory T cells in the modulation of the inflammatory response in PGs. In addition, the presence of a less effective regulatory environment in RCs, together with the high levels of inflammatory mediators as reported in the literature, may contribute to the greater growth potential of these lesions. Copyright © 2012 Elsevier Ltd. All rights reserved.

In vivo fluctuation of Tax, Foxp3, CTLA-4, and GITR mRNA expression in CD4(+)CD25(+) T cells of patients with human T-lymphotropic virus type 1-associated myelopathy.

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Ramirez, E; Cartier, L; Rodriguez, L; Alberti, C; Valenzuela, M A

2010-11-01

HTLV-1 Tax expression exerts an inhibitory effect on the Foxp3 transcription factor in CD4(+)CD25(+) T-regulatory cells (Treg). For a better understanding of the role of Tax mRNA in the gene expression of cellular markers we measured Tax, Foxp3, CTLA-4, GITR, TGF-β, and IL-10 mRNA in Treg cells of 50 patients with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP; 27 women and 23 men; mean age: 56.7 years). The control group consisted of 23 non-infected subjects (12 women and 11 men) with a mean age of 51.3 years. Real-time PCR was used to measure mRNA of Tax proteins and several cellular markers of Treg function. Determinations revealed a high level of Tax mRNA in HAM/TSP (124.35 copies/100 CD4(+)CD25(+) T cells). Foxp3, GITR, and CTLA-4 mRNA levels were lower in HAM/TSP patients (mean ± SD, 22.07 ± 0.78, 9.63 ± 0.36, and 4.54 ± 0.39, respectively) than in non-infected controls (47.15 ± 12.94, 22.14 ± 1.91, and 21.07 ± 2.31). Both groups had similar levels of TGF-β and IL-10. An inverse relationship was found between Tax levels and Foxp3, CTLA-4, and GITR levels. Conversely, there was a direct correlation between levels of Foxp3, GITR, and CTLA-4. Disease severity and evolution time did not correlate with Tax or Foxp3 levels. The present results suggest that Tax and Foxp3 mRNA vary with the same degree of disease severity in HAM/TSP patients. Tax fluctuations may affect CTLA-4 and GITR expression via the Foxp3 pathway, causing virus-induced dysfunction of CD4(+)CD25(+) T cells in HAM/TSP patients.

In vivo fluctuation of Tax, Foxp3, CTLA-4, and GITR mRNA expression in CD4+CD25+ T cells of patients with human T-lymphotropic virus type 1-associated myelopathy

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E. Ramirez

2010-11-01

Full Text Available HTLV-1 Tax expression exerts an inhibitory effect on the Foxp3 transcription factor in CD4+CD25+ T-regulatory cells (Treg. For a better understanding of the role of Tax mRNA in the gene expression of cellular markers we measured Tax, Foxp3, CTLA-4, GITR, TGF-β, and IL-10 mRNA in Treg cells of 50 patients with human T-lymphotropic virus type 1 (HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP; 27 women and 23 men; mean age: 56.7 years. The control group consisted of 23 non-infected subjects (12 women and 11 men with a mean age of 51.3 years. Real-time PCR was used to measure mRNA of Tax proteins and several cellular markers of Treg function. Determinations revealed a high level of Tax mRNA in HAM/TSP (124.35 copies/100 CD4+CD25+ T cells. Foxp3, GITR, and CTLA-4 mRNA levels were lower in HAM/TSP patients (mean ± SD, 22.07 ± 0.78, 9.63 ± 0.36, and 4.54 ± 0.39, respectively than in non-infected controls (47.15 ± 12.94, 22.14 ± 1.91, and 21.07 ± 2.31. Both groups had similar levels of TGF-β and IL-10. An inverse relationship was found between Tax levels and Foxp3, CTLA-4, and GITR levels. Conversely, there was a direct correlation between levels of Foxp3, GITR, and CTLA-4. Disease severity and evolution time did not correlate with Tax or Foxp3 levels. The present results suggest that Tax and Foxp3 mRNA vary with the same degree of disease severity in HAM/TSP patients. Tax fluctuations may affect CTLA-4 and GITR expression via the Foxp3 pathway, causing virus-induced dysfunction of CD4+CD25+ T cells in HAM/TSP patients.

Thorax irradiation triggers a local and systemic accumulation of immunosuppressive CD4+ FoxP3+ regulatory T cells

International Nuclear Information System (INIS)

Wirsdörfer, Florian; Cappuccini, Federica; Niazman, Muska; Leve, Simone de; Westendorf, Astrid M; Lüdemann, Lutz; Stuschke, Martin; Jendrossek, Verena

2014-01-01

Lymphocyte infiltration is a common feature of radiation-induced pneumonitis and fibrosis, but their contribution to the pathogenic processes is still unclear. Here, we addressed the impact of thorax irradiation on the T cell compartment with a focus on immunosuppressive regulatory T cells (Treg). C57BL/6 wild type mice (WT) received anesthesia only (sham controls, 0 Gy) or were exposed to a single dose of whole thorax irradiation (15 Gy). Immune cells from lung tissue, spleen, and cervical lymph nodes were collected 10 to 84 days post-irradiation and phenotypically characterized by flow cytometry. Whole thorax irradiation provoked an increased influx of CD3+ T cells at 42 and 84 days post-irradiation. In contrast, local irradiation caused a sustained reduction in CD3+ T cells in peripheral lymphoid tissues. Interestingly, we observed a significant local and systemic increase in the fraction of CD4+ T cells expressing the transcription factor forkhead box P3 (FoxP3), the phenotypic marker for murine Treg, at day 21 post-irradiation. The accumulation of Treg was associated with increased levels of T cells expressing surface proteins characteristic for recruitment and immunosuppressive activity, e.g. CD103, CTLA-4 and CD73. Importantly, Treg isolated at this time point were able to suppress CD4+ effector T cells to a similar extent as Treg isolated from control mice. The response of the adaptive immune system to whole thorax irradiation is characterized by local immunoactivation and systemic immunosuppression. The transient accumulation of immunosuppressive CD4+ FoxP3+ Treg may be required to protect the lung against excessive inflammation-induced tissue damage. Further investigations shall define the mechanisms underlying the accumulation of Treg and their role for the pathogenesis of radiation-induced lung disease

HTLV-1 bZIP factor induces inflammation through labile Foxp3 expression.

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Nanae Yamamoto-Taguchi

2013-09-01

Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 causes both a neoplastic disease and inflammatory diseases, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. The HTLV-1 basic leucine zipper factor (HBZ gene is encoded in the minus strand of the proviral DNA and is constitutively expressed in infected cells and ATL cells. HBZ increases the number of regulatory T (Treg cells by inducing the Foxp3 gene transcription. Recent studies have revealed that some CD4⁺Foxp3⁺ T cells are not terminally differentiated but have a plasticity to convert to other T-cell subsets. Induced Treg (iTreg cells tend to lose Foxp3 expression, and may acquire an effector phenotype accompanied by the production of inflammatory cytokines, such as interferon-γ (IFN-γ. In this study, we analyzed a pathogenic mechanism of chronic inflammation related with HTLV-1 infection via focusing on HBZ and Foxp3. Infiltration of lymphocytes was observed in the skin, lung and intestine of HBZ-Tg mice. As mechanisms, adhesion and migration of HBZ-expressing CD4⁺ T cells were enhanced in these mice. Foxp3⁻CD4⁺ T cells produced higher amounts of IFN-γ compared to those from non-Tg mice. Expression of Helios was reduced in Treg cells from HBZ-Tg mice and HAM/TSP patients, indicating that iTreg cells are predominant. Consistent with this finding, the conserved non-coding sequence 2 region of the Foxp3 gene was hypermethylated in Treg cells of HBZ-Tg mice, which is a characteristic of iTreg cells. Furthermore, Treg cells in the spleen of HBZ-transgenic mice tended to lose Foxp3 expression and produced an excessive amount of IFN-γ, while Foxp3 expression was stable in natural Treg cells of the thymus. HBZ enhances the generation of iTreg cells, which likely convert to Foxp3⁻T cells producing IFN-γ. The HBZ-mediated proinflammatory phenotype of CD4⁺ T cells is implicated in the pathogenesis of HTLV-1-associated inflammation.

Expression of Foxp3 in colorectal cancer but not in Treg cells correlates with disease progression in patients with colorectal cancer.

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Mia Kim

Full Text Available BACKGROUND: Regulatory T cells (Treg expressing the transcription factor forkhead-box protein P3 (Foxp3 have been identified to counteract anti-tumor immune responses during tumor progression. Besides, Foxp3 presentation by cancer cells itself may also allow them to evade from effector T-cell responses, resulting in a survival benefit of the tumor. For colorectal cancer (CRC the clinical relevance of Foxp3 has not been evaluated in detail. Therefore the aim of this study was to study its impact in colorectal cancer (CRC. METHODS AND FINDINGS: Gene and protein analysis of tumor tissues from patients with CRC was performed to quantify the expression of Foxp3 in tumor infiltrating Treg and colon cancer cells. The results were correlated with clinicopathological parameters and patients overall survival. Serial morphological analysis demonstrated Foxp3 to be expressed in cancer cells. High Foxp3 expression of the cancer cells was associated with poor prognosis compared to patients with low Foxp3 expression. In contrast, low and high Foxp3 level in tumor infiltrating Treg cells demonstrated no significant differences in overall patient survival. CONCLUSIONS: Our findings strongly suggest that Foxp3 expression mediated by cancer cells rather than by Treg cells contribute to disease progression.

Dissecting the regulatory microenvironment of a large animal model of non-Hodgkin lymphoma: evidence of a negative prognostic impact of FOXP3+ T cells in canine B cell lymphoma.

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Dammy Pinheiro

Full Text Available The cancer microenvironment plays a pivotal role in oncogenesis, containing a number of regulatory cells that attenuate the anti-neoplastic immune response. While the negative prognostic impact of regulatory T cells (Tregs in the context of most solid tissue tumors is well established, their role in lymphoid malignancies remains unclear. T cells expressing FOXP3 and Helios were documented in the fine needle aspirates of affected lymph nodes of dogs with spontaneous multicentric B cell lymphoma (BCL, proposed to be a model for human non-Hodgkin lymphoma. Multivariable analysis revealed that the frequency of lymph node FOXP3(+ T cells was an independent negative prognostic factor, impacting both progression-free survival (hazard ratio 1.10; p = 0.01 and overall survival (hazard ratio 1.61; p = 0.01 when comparing dogs showing higher than the median FOXP3 expression with those showing the median value of FOXP3 expression or less. Taken together, these data suggest the existence of a population of Tregs operational in canine multicentric BCL that resembles thymic Tregs, which we speculate are co-opted by the tumor from the periphery. We suggest that canine multicentric BCL represents a robust large animal model of human diffuse large BCL, showing clinical, cytological and immunophenotypic similarities with the disease in man, allowing comparative studies of immunoregulatory mechanisms.

TNFR2 expression on CD25hiFOXP3+ T cells induced upon TCR stimulation of CD4 T cells identifies maximal cytokine-producing effectors.

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Chindu eGovindaraj

2013-08-01

Full Text Available In this study, we show that CD25hiTNFR2+ cells can be rapidly generated in vitro from circulating CD4 lymphocytes by polyclonal stimuli anti-CD3 in the presence of anti-CD28. The in vitro induced CD25hiTNFR2+ T cells express a conventional Treg phenotype FOXP3+CTLA4+CD127lo/-, but produce effector and immunoregulatory cytokines including IL-2, IL-10 and IFN-g. These induced CD25hiTNFR2+ T cells do not suppress target cell proliferation, but enhance it instead. Thus the CD25hiTNFR2+ phenotype induced rapidly following CD3/28 cross linking of CD4 T cells identifies cells with maximal proliferative and effector cytokine producing capability. The in vivo counterpart of this cell population may play an important role in immune response initiation.

Transcriptome analysis of the human T lymphocyte cell line Jurkat and human peripheral blood mononuclear cells exposed to deoxynivalenol (DON): New mechanistic insights

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Katika, Madhumohan R. [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Hendriksen, Peter J.M. [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Shao, Jia [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Loveren, Henk van [Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Peijnenburg, Ad, E-mail: ad.peijnenburg@wur.nl [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Netherlands Toxicogenomics Centre (Netherlands)

2012-10-01

Deoxynivalenol (DON) or vomitoxin is a commonly encountered type-B trichothecene mycotoxin, produced by Fusarium species predominantly found in cereals and grains. DON is known to exert toxic effects on the gastrointestinal, reproductive and neuroendocrine systems, and particularly on the immune system. Depending on dose and exposure time, it can either stimulate or suppress immune function. The main objective of this study was to obtain a deeper insight into DON-induced effects on lymphoid cells. For this, we exposed the human T-lymphocyte cell line Jurkat and human peripheral blood mononuclear cells (PBMCs) to various concentrations of DON for various times and examined gene expression changes by DNA microarray analysis. Jurkat cells were exposed to 0.25 and 0.5 μM DON for 3, 6 and 24 h. Biological interpretation of the microarray data indicated that DON affects various processes in these cells: It upregulates genes involved in ribosome structure and function, RNA/protein synthesis and processing, endoplasmic reticulum (ER) stress, calcium-mediated signaling, mitochondrial function, oxidative stress, the NFAT and NF-κB/TNF-α pathways, T cell activation and apoptosis. The effects of DON on the expression of genes involved in ER stress, NFAT activation and apoptosis were confirmed by qRT-PCR. Other biochemical experiments confirmed that DON activates calcium-dependent proteins such as calcineurin and M-calpain that are known to be involved in T cell activation and apoptosis. Induction of T cell activation was also confirmed by demonstrating that DON activates NFATC1 and induces its translocation from the cytoplasm to the nucleus. For the gene expression profiling of PBMCs, cells were exposed to 2 and 4 μM DON for 6 and 24 h. Comparison of the Jurkat microarray data with those obtained with PBMCs showed that most of the processes affected by DON in the Jurkat cell line were also affected in the PBMCs. -- Highlights: ► The human T cell line Jurkat and human

Fenofibrate Enhances the In Vitro Differentiation of Foxp3+ Regulatory T Cells in Mice

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Zhou Zhou

2012-01-01

Full Text Available Foxp3+ regulatory T cells (Tregs play a critical role in maintaining immune self-tolerance. Reduced number and activity of Tregs are usually found in autoimmune and inflammatory diseases, and enhancing the differentiation of Tregs may be a promising therapeutic strategy. Some reports suggested an anti-inflammatory and anti-autoimmune potential for fenofibrate, a hypolipidemic drug used worldwide, whose lipid effects are mediated by the activation of peroxisome proliferator-activated receptor (PPAR. In the present paper, we found that fenofibrate dose-dependently increased transforming growth factor- and interleukin-2-induced Treg differentiation in vitro, by 1.96-fold from 0 to 20 M (12.59±1.34% to 24.69±3.03%, <0.05. Other PPAR activators, WY14643 (100 M, gemfibrozil (50 M, and bezafibrate (30 M, could not enhance Treg differentiation. In addition, PPAR could not upregulate the promoter activity of the Treg-specific transcription factor Foxp3. Fenofibrate might exert its function by enhancing Smad3 phosphorylation, a critical signal in Treg differentiation, via Akt suppression. Our work reveals a new PPAR independent anti-inflammatory mechanism of fenofibrate in up-regulating mouse Treg differentiation.

Induction of Foxp3-expressing regulatory T-cells by donor blood transfusion is required for tolerance to rat liver allografts.

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Yuta Abe

Full Text Available BACKGROUND: Donor-specific blood transfusion (DST prior to solid organ transplantation has been shown to induce long-term allograft survival in the absence of immunosuppressive therapy. Although the mechanisms underlying DST-induced allograft tolerance are not well defined, there is evidence to suggest DST induces one or more populations of antigen-specific regulatory cells that suppress allograft rejection. However, neither the identity nor the regulatory properties of these tolerogenic lymphocytes have been reported. Therefore, the objective of this study was to define the kinetics, phenotype and suppressive function of the regulatory cells induced by DST alone or in combination with liver allograft transplantation (LTx. METHODOLOGY/PRINCIPAL FINDINGS: Tolerance to Dark Agouti (DA; RT1(a rat liver allografts was induced by injection (iv of 1 ml of heparinized DA blood to naïve Lewis (LEW; RT1(l rats once per week for 4 weeks prior to LTx. We found that preoperative DST alone generates CD4(+ T-cells that when transferred into naïve LEW recipients are capable of suppressing DA liver allograft rejection and promoting long-term survival of the graft and recipient. However, these DST-generated T-cells did not express the regulatory T-cell (Treg transcription factor Foxp3 nor did they suppress alloantigen (DA-induced activation of LEW T-cells in vitro suggesting that these lymphocytes are not fully functional regulatory Tregs. We did observe that DST+LTx (but not DST alone induced the time-dependent formation of CD4(+Foxp3(+ Tregs that potently suppressed alloantigen-induced activation of naïve LEW T-cells in vitro and liver allograft rejection in vivo. Finally, we present data demonstrating that virtually all of the Foxp3-expressing Tregs reside within the CD4(+CD45RC(- population whereas in which approximately 50% of these Tregs express CD25. CONCLUSIONS/SIGNIFICANCE: We conclude that preoperative DST, in the absence of liver allograft

FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

International Nuclear Information System (INIS)

Ma, Gui-Fen; Chen, Shi-Yao; Sun, Zhi-Rong; Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng; Ma, Li-Li; Lian, Jing-Jing; Song, Dong-Li

2013-01-01

Highlights: ► The article revealed FoxP3 gene function in gastric cancer firstly. ► Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. ► Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. ► Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. ► FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.

Superior Cervical Ganglia Neurons Induce Foxp3+ Regulatory T Cells via Calcitonin Gene-Related Peptide.

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Szklany, Kirsten; Ruiter, Evelyn; Mian, Firoz; Kunze, Wolfgang; Bienenstock, John; Forsythe, Paul; Karimi, Khalil

2016-01-01

The nervous and immune systems communicate bidirectionally, utilizing diverse molecular signals including cytokines and neurotransmitters to provide an integrated response to changes in the body's internal and external environment. Although, neuro-immune interactions are becoming better understood under inflammatory circumstances and it has been evidenced that interaction between neurons and T cells results in the conversion of encephalitogenic T cells to T regulatory cells, relatively little is known about the communication between neurons and naïve T cells. Here, we demonstrate that following co-culture of naïve CD4+ T cells with superior cervical ganglion neurons, the percentage of Foxp3 expressing CD4+CD25+ cells significantly increased. This was mediated in part by immune-regulatory cytokines TGF-β and IL-10, as well as the neuropeptide calcitonin gene-related peptide while vasoactive intestinal peptide was shown to play no role in generation of T regulatory cells. Additionally, T cells co-cultured with neurons showed a decrease in the levels of pro-inflammatory cytokine IFN-γ released upon in vitro stimulation. These findings suggest that the generation of Tregs may be promoted by naïve CD4+ T cell: neuron interaction through the release of neuropeptide CGRP.

Genetic polymorphism in FOXP3 gene: imbalance in regulatory T ...

Indian Academy of Sciences (India)

2013-04-02

Apr 2, 2013 ... In contrast, high Treg levels have been reported in peripheral blood, lymph ... patients with different types of cancer. ... Therefore, in the present study, the relationship between genetic ... (amino acids 240–261) and a carboxy-terminal forkhead ... FOXP3 in tumour cells indicates that FOXP3-targeted drugs.

Dynamic changes of Foxp3(+) regulatory T cells in spleen and brain of canine distemper virus-infected dogs.

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Qeska, V; Barthel, Y; Iseringhausen, M; Tipold, A; Stein, V M; Khan, M A; Baumgärtner, W; Beineke, A

2013-12-15

Canine distemper virus (CDV) infection causes immunosuppression and demyelinating leukoencephalitis in dogs. In viral diseases, an ambiguous function of regulatory T cells (Treg), with both beneficial effects by reducing immunopathology and detrimental effects by inhibiting antiviral immunity, has been described. However, the role of Treg in the pathogenesis of canine distemper remains unknown. In order to determine the effect of CDV upon immune homeostasis, the amount of Foxp3(+) Treg in spleen and brain of naturally infected dogs has been determined by immunohistochemistry. In addition, splenic cytokine expression has been quantified by reverse transcriptase polymerase chain reaction. Splenic depletion of Foxp3(+) Treg was associated with an increased mRNA-expression of tumor necrosis factor and decreased transcription of interleukin-2 in the acute disease phase, indicative of disturbed immunological counter regulation in peripheral lymphoid organs. In the brain, a lack of Foxp3(+) Treg in predemyelinating and early demyelinating lesions and significantly increased infiltrations of Foxp3(+) Treg in chronic demyelinating lesions were observed. In conclusion, disturbed peripheral and CNS immune regulation associated with a reduction of Treg represents a potential prerequisite for excessive neuroinflammation and early lesion development in canine distemper leukoencephalitis. © 2013 Elsevier B.V. All rights reserved.

Foxp3(+) T cells regulate immunoglobulin a selection and facilitate diversification of bacterial species responsible for immune homeostasis.

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Kawamoto, Shimpei; Maruya, Mikako; Kato, Lucia M; Suda, Wataru; Atarashi, Koji; Doi, Yasuko; Tsutsui, Yumi; Qin, Hongyan; Honda, Kenya; Okada, Takaharu; Hattori, Masahira; Fagarasan, Sidonia

2014-07-17

Foxp3(+) T cells play a critical role for the maintenance of immune tolerance. Here we show that in mice, Foxp3(+) T cells contributed to diversification of gut microbiota, particularly of species belonging to Firmicutes. The control of indigenous bacteria by Foxp3(+) T cells involved regulatory functions both outside and inside germinal centers (GCs), consisting of suppression of inflammation and regulation of immunoglobulin A (IgA) selection in Peyer's patches, respectively. Diversified and selected IgAs contributed to maintenance of diversified and balanced microbiota, which in turn facilitated the expansion of Foxp3(+) T cells, induction of GCs, and IgA responses in the gut through a symbiotic regulatory loop. Thus, the adaptive immune system, through cellular and molecular components that are required for immune tolerance and through the diversification as well as selection of antibody repertoire, mediates host-microbial symbiosis by controlling the richness and balance of bacterial communities required for homeostasis. Copyright © 2014 Elsevier Inc. All rights reserved.

Changes in natural Foxp3(+Treg but not mucosally-imprinted CD62L(negCD38(+Foxp3(+Treg in the circulation of celiac disease patients.

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Marieke A van Leeuwen

Full Text Available BACKGROUND: Celiac disease (CD is an intestinal inflammation driven by gluten-reactive CD4(+ T cells. Due to lack of selective markers it has not been determined whether defects in inducible regulatory T cell (Treg differentiation are associated with CD. This is of importance as changes in numbers of induced Treg could be indicative of defects in mucosal tolerance development in CD. Recently, we have shown that, after encounter of retinoic acid during differentiation, circulating gut-imprinted T cells express CD62L(negCD38(+. Using this new phenotype, we now determined whether alterations occur in the frequency of natural CD62L(+Foxp3(+ Treg or mucosally-imprinted CD62L(negCD38(+Foxp3(+ Treg in peripheral blood of CD patients. In particular, we compared pediatric CD, aiming to select for disease at onset, with adult CD. METHODS: Cell surface markers, intracellular Foxp3 and Helios were determined by flow cytometry. Foxp3 expression was also detected by immunohistochemistry in duodenal tissue of CD patients. RESULTS: In children, the percentages of peripheral blood CD4(+Foxp3(+ Treg were comparable between CD patients and healthy age-matched controls. Differentiation between natural and mucosally-imprinted Treg on the basis of CD62L and CD38 did not uncover differences in Foxp3. In adult patients on gluten-free diet and in refractory CD increased percentages of circulating natural CD62L(+Foxp3(+ Treg, but normal mucosally-imprinted CD62L(negCD38(+Foxp3(+ Treg frequencies were observed. CONCLUSIONS: Our data exclude that significant numeric deficiency of mucosally-imprinted or natural Foxp3(+ Treg explains exuberant effector responses in CD. Changes in natural Foxp3(+ Treg occur in a subset of adult patients on a gluten-free diet and in refractory CD patients.

IL-33 Effect on Quantitative Changes of CD4+CD25highFOXP3+ Regulatory T Cells in Children with Type 1 Diabetes

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Monika Ryba-Stanisławowska

2016-01-01

Full Text Available IL-33 is an IL-1 cytokine family member, with ability to induce both Th1 and Th2 immune responses. It binds to ST2 receptor, whose deficiency is associated with enhanced inflammatory response. The most recent studies have shown the immunoregulatory effect of IL-33 on Tregs in animal models. As type 1 diabetes is an autoimmune, inflammatory disease, where Treg defects have been described, we aimed to analyze the in vitro influence of recombinant IL-33 on quantitative properties of regulatory CD4+CD25highFOXP3+ T cells. CD4+CD25highFOXP3+ as well as CD4+CD25highFOXP3+ST2+ Tregs were analyzed by flow cytometry. In a group of patients with type 1 diabetes in vitro IL-33 treatment induced regulatory CD4+CD25highFOXP3+ cell frequencies as well as upregulating the surface expression of ST2 molecule. In addition, the number of CD4+CD25highFOXP3+ cells carrying ST2 receptor increased significantly. Similar effect was observed in case of the FOXP3 expression. We did not observe any significant changes in IL-33 treated cells of healthy controls. The level of ST2 was higher in serum of patients with type 1 diabetes in comparison to their healthy counterparts. We propose that IL-33 becomes an additional immunostimulatory factor used to induce Treg expansion in future clinical trials of adoptive therapy in type 1 diabetes.

β-cell-specific IL-2 therapy increases islet Foxp3+Treg and suppresses type 1 diabetes in NOD mice.

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Johnson, Mark C; Garland, Alaina L; Nicolson, Sarah C; Li, Chengwen; Samulski, R Jude; Wang, Bo; Tisch, Roland

2013-11-01

Interleukin-2 (IL-2) is a critical cytokine for the homeostasis and function of forkhead box p3-expressing regulatory T cells (Foxp3(+)Tregs). Dysregulation of the IL-2-IL-2 receptor axis is associated with aberrant Foxp3(+)Tregs and T cell-mediated autoimmune diseases such as type 1 diabetes. Treatment with recombinant IL-2 has been reported to enhance Foxp3(+)Tregs and suppress different models of autoimmunity. However, efficacy of IL-2 therapy is dependent on achieving sufficient levels of IL-2 to boost tissue-resident Foxp3(+)Tregs while avoiding the potential toxic effects of systemic IL-2. With this in mind, adeno-associated virus (AAV) vector gene delivery was used to localize IL-2 expression to the islets of NOD mice. Injection of a double-stranded AAV vector encoding IL-2 driven by a mouse insulin promoter (dsAAVmIP-IL2) increased Foxp3(+)Tregs in the islets but not the draining pancreatic lymph nodes. Islet Foxp3(+)Tregs in dsAAVmIP-IL2-treated NOD mice exhibited enhanced fitness marked by increased expression of Bcl-2, proliferation, and suppressor function. In contrast, ectopic IL-2 had no significant effect on conventional islet-infiltrating effector T cells. Notably, β-cell-specific IL-2 expression suppressed late preclinical type 1 diabetes in NOD mice. Collectively, these findings demonstrate that β-cell-specific IL-2 expands an islet-resident Foxp3(+)Tregs pool that effectively suppresses ongoing type 1 diabetes long term.

Effects of in vitro Brevetoxin Exposure on Apoptosis and Cellular Metabolism in a Leukemic T Cell Line (Jurkat

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John W. Sleasman

2008-06-01

Full Text Available Harmful algal blooms (HABs of the toxic dinoflagellate, Karenia brevis, produce red tide toxins, or brevetoxins. Significant health effects associated with red tide toxin exposure have been reported in sea life and in humans, with brevetoxins documented within immune cells from many species. The objective of this research was to investigate potential immunotoxic effects of brevetoxins using a leukemic T cell line (Jurkat as an in vitro model system. Viability, cell proliferation, and apoptosis assays were conducted using brevetoxin congeners PbTx-2, PbTx-3, and PbTx-6. The effects of in vitro brevetoxin exposure on cell viability and cellular metabolism or proliferation were determined using trypan blue and MTT (1-(4,5-dimethylthiazol-2-yl-3,5- diphenylformazan, respectively. Using MTT, cellular metabolic activity was decreased in Jurkat cells exposed to 5 - 10 μg/ml PbTx-2 or PbTx-6. After 3 h, no significant effects on cell viability were observed with any toxin congener in concentrations up to 10 μg/ml. Viability decreased dramatically after 24 h in cells treated with PbTx-2 or -6. Apoptosis, as measured by caspase-3 activity, was significantly increased in cells exposed to PbTx-2 or PbTx-6. In summary, brevetoxin congeners varied in effects on Jurkat cells, with PbTx-2 and PbTx-6 eliciting greater cellular effects compared to PbTx-3.

The clinical and pathogenetic value of Foxp3+ T regulatory cells in rheumatoid arthritis

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A. S. Avdeeva

2016-01-01

Full Text Available T regulatory cells (Tregs play a key role in the immune system due to the suppression of a hyperimmune response to autoantigens and opportunistic enteric microorganisms. In recent years, there has been evidence that Tregs can suppress various immunoinflammatory responses to a wide range of physiological and pathological stimuli, including microorganisms, tumor cells, allogeneic grafts, and fetal cells.Tregs express a broad spectrum of membrane molecules that determine their functional activity and make it possible to identify these cells; however, none has discovered a universal surface marker that would distinguish this cell subpopulation from a pool of T lymphocytes. The most specific intracellular marker for Tregs is the nuclear transcription factor Foxp3 that is of fundamental importance in the development of Tregs and their inhibitory function.The results of the vast majority of studies indicate that there are increased numbers of Tregs in the synovial fluid of patients with rheumatoid arthritis (RA; however, the data on the level of this cell population in their peripheral blood are very contradictory. The majority of investigators have observed a decrease in the percentage of circulating Tregs while other studies have revealed its increase or no differences from the corresponding value of healthy donors or patients with osteoarthritis. It is believed that a quantitative defect in CD4+CD25+Foxp3+CD127 regulatory cells is especially characteristic of early RA and associated with the risk of the latter in asymptomatic patients positive for anti-cyclic citrullinated peptide antibodies. The use of disease-modifying antirheumatic drugs and biologic agents is accompanied by a certain change in the level and functional activity of Tregs, which is responsible for the therapeutic effect of the medicaments.Thus, an important part is assigned to Tregs in the pathogenesis of autoimmune rheumatic diseases, RA in particular. The decrease in the level

FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

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Ma, Gui-Fen [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: shiyao_chen@163.com [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Sun, Zhi-Rong [Department of Anesthesiology, Cancer Center, Fudan University, Shanghai (China); Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Li-Li; Lian, Jing-Jing [Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Song, Dong-Li [Biomedical Research Center, Zhongshan Hospital, Fudan University, Shanghai (China)

2013-01-11

Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis

(99) Tc-methylene diphosphonate improves rheumatoid arthritis disease activity by increasing the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs.

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Su, Dinglei; Shen, Minning; Gu, Bingjie; Wang, Xiaoqin; Wang, Dandan; Li, Xia; Sun, Lingyun

2016-06-01

γδ T cells exhibit important functions in the pathogenesis of rheumatoid arthritis (RA). In recent years, numerous studies harnessed the γδ T cell-activating capacity of aminobiphosphonates for the treatment of malignant tumors. As (99) Tc-methylene diphosphonate ((99) Tc-MDP) has long been widely used for the treatment of RA in China with good efficacy, we are interested in whether this drug exerts its therapeutic effect on RA by modulating peripheral γδ T cells of RA patients. To investigate the effect of (99) Tc-MDP on the frequency of γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs in the peripheral blood of patients with active RA. Nineteen patients with active RA were treated with (99) Tc-MDP intravenously at a dose of 20 μg/day consecutively for 10-14 days. Before and after treatment, the main clinical and laboratory parameters for each patient were evaluated. The frequency of CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs was detected by flow cytometry. Serum levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and transforming growth factor (TGF)-β were measured with enzyme-linked immunosorbent assay. After intravenous (99) Tc-MDP therapy, the frequency of peripheral CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs were significantly elevated, paralleled with decreased serum levels of TNF-α and IL-6 and increased level of serum TGF-β. The elevation of peripheral CD3(+) γδ(+) T cells was positively correlated with increased serum TGF-β and decreased disease activity. (99) Tc-MDP may improve the activity of RA through upregulating the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs as well as affecting the serum cytokine environment by increasing TGF-β and decreasing TNF-α and IL-6. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Effects of valproic acid and pioglitazone on cell cycle progression and proliferation of T-cell acute lymphoblastic leukemia Jurkat cells

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Marie Saghaeian Jazi

2016-07-01

Full Text Available Objective(s: T-cell acute lymphoblastic leukemia (T-ALL is an aggressive hematologic malignant tumor. Administration of chemical compounds influencing apoptosis and T cell development has been discussed as promising novel therapeutic strategies. Valproic acid (VPA as a recently emerged anti-neoplastic histone deacetylase (HDAC inhibitor and pioglitazone (PGZ as a high-affinity peroxisome proliferator-activated receptor-gamma (PPARγ agonist have been shown to induce apoptosis and cell cycle arrest in different studies. Here, we aimed to investigate the underlying molecular mechanisms involved in anti-proliferative effects of these compounds on human Jurkat cells. Materials and Methods: Treated cells were evaluated for cell cycle progression and apoptosis using flowcytometry and MTT viability assay. Real-time RT-PCR was carried out to measure the alterations in key genes associated with cell death and cell cycle arrest. Results: Our findings illustrated that both VPA and PGZ can inhibit Jurkat E6.1 cells in vitro after   24 hr; however, PGZ 400 μM presents the most anti-proliferative effect. Interestingly, treated cells have been arrested in G2/M with deregulated cell division cycle 25A (Cdc25A phosphatase and cyclin-dependent kinase inhibitor 1B (CDKN1B or p27 expression. Expression of cyclin D1 gene was inhibited when DNA synthesis entry was declined. Cell cycle deregulation in PGZ and VPA-exposed cells generated an increase in the proportion of aneuploid cell population, which has not reported before. Conclusion: These findings define that anti-proliferative effects of PGZ and VPA on Jurkat cell line are mediated by cell cycle deregulation. Thus, we suggest PGZ and VPA may relieve potential therapeutic application against apoptosis-resistant malignancies.

FOXP3 and GARP (LRRC32): the master and its minion.

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Probst-Kepper, Michael; Buer, Jan

2010-02-05

The transcription factor FOXP3 is essential for the development and function of CD4+CD25hiFOXP3+ regulatory T (T(reg)) cells, but also expressed in activated human helper T cells without acquisition of a regulatory phenotype. This comment focuses on glycoprotein-A repetitions predominant (GARP or LRRC32) recently identified as specific marker of activated human T(reg) cells, which may provide the missing link toward a better molecular definition of the regulatory phenotype.

Inhibition of Allograft Inflammatory Factor-1 in Dendritic Cells Restrains CD4+ T Cell Effector Responses and Induces CD25+Foxp3+ T Regulatory Subsets

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Diana M. Elizondo

2017-11-01

Full Text Available Allograft inflammatory factor-1 (AIF1 is a cytoplasmic scaffold protein shown to influence immune responses in macrophages and microglial cells. The protein contains Ca2+ binding EF-hand and PDZ interaction domains important for mediating intracellular signaling complexes. This study now reports that AIF1 is expressed in CD11c+ dendritic cells (DC and silencing of expression restrains induction of antigen-specific CD4+ T cell effector responses. AIF1 knockdown in murine DC resulted in impaired T cell proliferation and skewed polarization away from T helper type 1 and 17 fates. In turn, there was a parallel expansion of IL-10-producing and CD25+Foxp3+ T regulatory subsets. These studies are the first to demonstrate that AIF1 expression in DC serves as a potent governor of cognate T cell responses and presents a novel target for engineering tolerogenic DC-based immunotherapies.

CD147 and CD98 complex-mediated homotypic aggregation attenuates the CypA-induced chemotactic effect on Jurkat T cells.

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Guo, Na; Zhang, Kui; Lv, Minghua; Miao, Jinlin; Chen, Zhinan; Zhu, Ping

2015-02-01

Homotypic cell aggregation plays important roles in physiological and pathological processes, including embryogenesis, immune responses, angiogenesis, tumor cell invasion and metastasis. CD147 has been implicated in most of these phenomena, and it was identified as a T cell activation-associated antigen due to its obvious up-regulation in activated T cells. However, the explicit function and mechanism of CD147 in T cells have not been fully elucidated. In this study, large and compact aggregates were observed in Jurkat T cells after treatment with the specific CD147 monoclonal antibody HAb18 or after the expression of CD147 was silenced by RNA interference, which indicated an inhibitory effect of CD147 in T cell homotypic aggregation. Knocking down CD147 expression resulted in a significant decrease in CD98, along with prominent cell aggregation, similar to that treated by CD98 and CD147 monoclonal antibodies. Furthermore, decreased cell chemotactic activity was observed following CD147- and CD98-mediated cell aggregation, and increased aggregation was correlated with a decrease in the chemotactic ability of the Jurkat T cells, suggesting that CD147- and CD98-mediated homotypic cell aggregation plays a negative role in T cell chemotaxis. Our data also showed that p-ERK, p-ZAP70, p-CD3ζ and p-LCK were significantly decreased in the CD147- and CD98-knocked down Jurkat T cells, which suggested that decreased CD147- and/or CD98-induced homotypic T cell aggregation and aggregation-inhibited chemotaxis might be associated with these signaling pathways. A role for CD147 in cell aggregation and chemotaxis was further indicated in primary CD4(+) T cells. Similarly, low expression of CD147 in primary T cells induced prominent cell aggregation and this aggregation attenuated primary T cell chemotactic ability in response to CypA. Our results have demonstrated the correlation between homotypic cell aggregation and the chemotactic response of T cells to CypA, and these data

Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

KAUST Repository

Schmidt, Angelika

2018-04-27

BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest, and first-in-man trials of Treg transfer have achieved promising outcomes. Yet, the mechanisms governing induced Treg (iTreg) differentiation and the regulation of FOXP3 are incompletely understood.ResultsTo gain a comprehensive and unbiased molecular understanding of FOXP3 induction, we performed time-series RNA sequencing (RNA-Seq) and proteomics profiling on the same samples during human iTreg differentiation. To enable the broad analysis of universal FOXP3-inducing pathways, we used five differentiation protocols in parallel. Integrative analysis of the transcriptome and proteome confirmed involvement of specific molecular processes, as well as overlap of a novel iTreg subnetwork with known Treg regulators and autoimmunity-associated genes. Importantly, we propose 37 novel molecules putatively involved in iTreg differentiation. Their relevance was validated by a targeted shRNA screen confirming a functional role in FOXP3 induction, discriminant analyses classifying iTregs accordingly, and comparable expression in an independent novel iTreg RNA-Seq dataset.ConclusionThe data generated by this novel approach facilitates understanding of the molecular mechanisms underlying iTreg generation as well as of the concomitant changes in the transcriptome and proteome. Our results provide a reference map exploitable for future discovery of markers and drug candidates governing control of Tregs, which has important implications for the treatment of cancer, autoimmune, and inflammatory diseases.

Exposure of Jurkat cells to bis (tri-n-butyltin) oxide (TBTO) induces transcriptomics changes indicative for ER- and oxidative stress, T cell activation and apoptosis

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Katika, Madhumohan R.; Hendriksen, Peter J.M.; Loveren, Henk van; Peijnenburg, Ad

2011-01-01

Tributyltin oxide (TBTO) is an organotin compound that is widely used as a biocide in agriculture and as an antifouling agent in paints. TBTO is toxic for many cell types, particularly immune cells. The present study aimed to identify the effects of TBTO on the human T lymphocyte cell line Jurkat. Cells were treated with 0.2 and 0.5 μM TBTO for 3, 6, 12 and 24 h and then subjected to whole genome gene expression microarray analysis. The biological interpretation of the gene expression profiles revealed that endoplasmic reticulum (ER) stress is among the earliest effects of TBTO. Simultaneously or shortly thereafter, oxidative stress, activation of NFKB and NFAT, T cell activation, and apoptosis are induced. The effects of TBTO on genes involved in ER stress, NFAT pathway, T cell activation and apoptosis were confirmed by qRT-PCR. Activation and nuclear translocation of NFATC1 and the oxidative stress response proteins NRF2 and KEAP1 were confirmed by immunocytology. Taking advantage of previously published microarray data, we demonstrated that the induction of ER stress, oxidative stress, T cell activation and apoptosis by TBTO is not unique for Jurkat cells but does also occur in mouse thymocytes both ex vivo and in vivo and rat thymocytes ex vivo. We propose that the induction of ER stress leading to a T cell activation response is a major factor in the higher sensitivity of immune cells above other types of cells for TBTO. - Research Highlights: → The human T lymphocyte cell line Jurkat was exposed to TBTO. → Whole-genome microarray experiments were performed. → Data analysis revealed the induction of ER stress and activation of NFAT and NFKB. → Exposure to TBTO also led to T cell activation, oxidative stress and apoptosis.

TGF-β-induced IκB-ζ controls Foxp3 gene expression

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MaruYama, Takashi, E-mail: ta-maru@umin.ac.jp [Laboratory of Cell Recognition and Response, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578 (Japan); School of Medicine, Gifu University, Gifu 501-1194 (Japan)

2015-08-21

Inhibitor of kappa B (IκB)-ζ, a member of the nuclear IκB family of proteins, is induced by the transforming growth factor (TGF)-β signaling pathway and plays a pivotal role in maintaining the balance of T helper (Th) cell subsets. IκB-ζ deficiency results in reduced percentages of Th17 cells and increased percentages of Th1 cells. In this study, the effects of IκB-ζ deficiency on T-cell subsets were examined further. The data showed that IκB-ζ-deficient T cells had a high capacity for generation of regulatory T cells (Tregs) when T cells were cultured under TGF-β stimulation in the presence of cytokine-neutralizing antibodies. Mechanistically, IκB-ζ itself negatively regulated activation of the Foxp3 promoter in a nuclear factor of kappaB-dependent manner. Thus, this study showed that IκB-ζ controlled Treg differentiation. - Highlights: • IκB-ζ-deficient T cells exhibited increased generation of Foxp3{sup +} Tregs. • IκB-ζ played a key role in Foxp3 gene expression. • Retroviral overexpression of IκB-ζ was achieved in T cells.

TGF-β-induced IκB-ζ controls Foxp3 gene expression

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MaruYama, Takashi

2015-01-01

Inhibitor of kappa B (IκB)-ζ, a member of the nuclear IκB family of proteins, is induced by the transforming growth factor (TGF)-β signaling pathway and plays a pivotal role in maintaining the balance of T helper (Th) cell subsets. IκB-ζ deficiency results in reduced percentages of Th17 cells and increased percentages of Th1 cells. In this study, the effects of IκB-ζ deficiency on T-cell subsets were examined further. The data showed that IκB-ζ-deficient T cells had a high capacity for generation of regulatory T cells (Tregs) when T cells were cultured under TGF-β stimulation in the presence of cytokine-neutralizing antibodies. Mechanistically, IκB-ζ itself negatively regulated activation of the Foxp3 promoter in a nuclear factor of kappaB-dependent manner. Thus, this study showed that IκB-ζ controlled Treg differentiation. - Highlights: • IκB-ζ-deficient T cells exhibited increased generation of Foxp3 + Tregs. • IκB-ζ played a key role in Foxp3 gene expression. • Retroviral overexpression of IκB-ζ was achieved in T cells

[Changes of FoxP3, CD4(+)CD25(+) regulatory T cells, TLR2 and TLR9 in children with infectious mononucleosis].

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Wang, Qiang; Wang, Zuo-Feng; Cao, Mei; Wang, Zhi-Ying

2013-04-01

The aim of this study was to investigate the effects of TLR2, TLR9, CD4(+)CD25(+) regulatory T cells (Treg) and transcription factor FoxP3 in the pathogenesis of children with infectious mononucleosis (IM). Thirty-five acute IM patients admitted in our hospital from April 2010 to January 2011 were enrolled in this study. Thirty-five healthy subjects were taken as control. The thirty-five patients before treatment were considered as patients in acute stage, after treatment and without clinical symptom they were thought as patients in recovery stage. The expression levels of TLR2, TLR9 and FoxP3 mRNA were detected by real time PCR using SYBR Green I. The expression of T lymphocyte subset CD4(+)CD25(+) in peripheral blood mononuclear cells was detected by flow cytometry. The results showed that the relative levels of TLR2 mRNA (4.03 ± 0.56), TLR9 mRNA (8.88 ± 1.56) in peripheral blood mononuclear cells of IM patients in acute stage were significantly higher than those of the controls [TLR2 mRNA (2.22 ± 0.57), TLR9 mRNA (3.63 ± 1.30)] and IM patients in recovery stage [TLR2 mRNA (2.76 ± 0.83), TLR9 mRNA (5.34 ± 1.60)] (P 0.05). It is concluded that the expression of CD4(+)CD25(+)regulatory T cells is reduced, and its special transcription factor FoxP3 mRNA is down-regulated, but expression levels of TLR2 mRNA, TLR9 mRNA are up-regulated in IM patients of acute stage.

Methionine enkephalin (MENK) inhibits tumor growth through regulating CD4+Foxp3+ regulatory T cells (Tregs) in mice.

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Li, Xuan; Meng, Yiming; Plotnikoff, Nicolas P; Youkilis, Gene; Griffin, Noreen; Wang, Enhua; Lu, Changlong; Shan, Fengping

2015-01-01

Methionine enkephalin (MENK), an endogenous neuropeptide, plays an crucial role in both neuroendocrine and immune systems. CD4+Foxp3+ regulatory T cells (Tregs) are identified as a major subpopulation of T lymphocytes in suppressing immune system to keep balanced immunity. The aim of this research work was to elucidate the mechanisms via which MENK interacts with Tregs in cancer situation. The influence of MENK on transforming growth factor-β (TGF-β) mediated conversion from naïve CD4+CD25- T cells to CD4+CD25+ Tregs was determined and the data from flow cytometry (FCM) analysis indicated that MENK effectively inhibited the expression of Foxp3 during the process of TGF-βinduction. Furthermore, this inhibiting process was accompanied by diminishing phosphorylation and nuclear translocation of Smad2/3, confirmed by western blot (WB) analysis and immunofluorescence (IF) at molecular level. We established sarcoma mice model with S180 to investigate whether MENK could modulate Tregs in tumor circumstance. Our findings showed that MENK delayed the development of tumor in S180 tumor bearing mice and down-regulated level of Tregs. Together, these novel findings reached a conclusion that MENK could inhibit Tregs activity directly and retard tumor development through down-regulating Tregs in mice. This work advances the deepening understanding of the influence of MENK on Tregs in cancer situation, and relation of MENK with immune system, supporting the implication of MENK as a new strategy for cancer immunotherapy.

FOXP3 and GARP (LRRC32): the master and its minion

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Buer Jan; Probst-Kepper Michael

2010-01-01

Abstract The transcription factor FOXP3 is essential for the development and function of CD4+CD25hiFOXP3+ regulatory T (Treg) cells, but also expressed in activated human helper T cells without acquisition of a regulatory phenotype. This comment focuses on glycoprotein-A repetitions predominant (GARP or LRRC32) recently identified as specific marker of activated human Treg cells, which may provide the missing link toward a better molecular definition of the regulatory phenotype. Reviewers: Dr...

FoxP3(+)CD4(+)CD25(+) T cells with regulatory properties can be cultured from colonic mucosa of patients with Crohn's disease

DEFF Research Database (Denmark)

Rømer, Johanne Lade

2005-01-01

Summary CD4(+)CD25(+) regulatory T cells (T(regs)) are involved in the maintenance of peripheral tolerance and ensure a balanced immune response competent of fighting pathogens and at the same time recognizing commensals as harmless. This feature is lost in Crohn's disease (CD). The forkhead/wing......(+) T cells. Thus, we demonstrate that FoxP3(+)CD4(+)CD25(+) T cells with regulatory properties can be propagated in vitro from inflamed mucosa of CD patients, which may be of interest in adoptive immunotherapy....

Successful validation of genomic biomarkers for human immunotoxicity in Jurkat T cells in vitro.

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Schmeits, Peter C J; Shao, Jia; van der Krieken, Danique A; Volger, Oscar L; van Loveren, Henk; Peijnenburg, Ad A C M; Hendriksen, Peter J M

2015-07-01

Previously, we identified 25 classifier genes that were able to assess immunotoxicity using human Jurkat T cells. The present study aimed to validate these classifiers. For that purpose, Jurkat cells were exposed for 6 h to subcytotoxic doses of nine immunotoxicants, five non-immunotoxicants and four compounds for which human immunotoxicity has not yet been fully established. RNA was isolated and subjected to Fluidigm quantitative real time (qRT)-PCR analysis. The sensitivity, specificity and accuracy of the screening assay as based on the nine immunotoxicants and five non-immunotoxicants used in this study were 100%, 80% and 93%, respectively, which is better than the performance in our previous study. Only one compound was classified as false positive (benzo-e-pyrene). Of the four potential (non-)immunotoxicants, chlorantraniliprole and Hidrasec were classified immunotoxic and Sunset yellow and imidacloprid as non-immunotoxic. ToxPi analysis of the PCR data provided insight in the molecular pathways that were affected by the compounds. The immunotoxicants 2,3-dichloro-propanol and cypermethrin, although structurally different, affected protein metabolism and cholesterol biosynthesis and transport. In addition, four compounds, i.e. chlorpyrifos, aldicarb, benzo-e-pyrene and anti-CD3, affected genes in cholesterol metabolism and transport, protein metabolism and transcription regulation. qRT-PCR on eight additional genes coding for similar processes as defined in ToxPi analyzes, supported these results. In conclusion, the 25 immunotoxic classifiers performed very well in a screening with new non-immunotoxic and immunotoxic compounds. Therefore, the Jurkat screening assay has great promise to be applied within a tiered approach for animal free testing of human immunotoxicity. Copyright © 2014 John Wiley & Sons, Ltd.

Myocardial Gene Expression of T-bet, GATA-3, Ror-γt, FoxP3, and Hallmark Cytokines in Chronic Chagas Disease Cardiomyopathy: An Essentially Unopposed TH1-Type Response

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Luciana Gabriel Nogueira

2014-01-01

Full Text Available Background. Chronic Chagas disease cardiomyopathy (CCC, a late consequence of Trypanosoma cruzi infection, is an inflammatory cardiomyopathy with prognosis worse than those of noninflammatory etiology (NIC. Although the T cell-rich myocarditis is known to play a pathogenetic role, the relative contribution of each of the functional T cell subsets has never been thoroughly investigated. We therefore assessed gene expression of cytokines and transcription factors involved in differentiation and effector function of each functional T cell subset (TH1/TH2/TH17/Treg in CCC, NIC, and heart donor myocardial samples. Methods and Results. Quantitative PCR showed markedly upregulated expression of IFN-γ and transcription factor T-bet, and minor increases of GATA-3; FoxP3 and CTLA-4; IL-17 and IL-18 in CCC as compared with NIC samples. Conversely, cytokines expressed by TH2 cells (IL-4, IL-5, and IL-13 or associated with Treg (TGF-β and IL-10 were not upregulated in CCC myocardium. Expression of TH1-related genes such as T-bet, IFN-γ, and IL-18 correlated with ventricular dilation, FoxP3, and CTLA-4. Conclusions. Results are consistent with a strong local TH1-mediated response in most samples, possibly associated with pathological myocardial remodeling, and a proportionally smaller FoxP3+CTLA4+ Treg cell population, which is unable to completely curb IFN-γ production in CCC myocardium, therefore fueling inflammation.

FOXP3: required but not sufficient. the role of GARP (LRRC32) as a safeguard of the regulatory phenotype.

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Probst-Kepper, M; Balling, R; Buer, J

2010-08-01

FOXP3 is essential for the development and function of regulatory CD4(+)CD25(hi) T (T(reg)) cells. However, recent evidence suggests that FOXP3 alone is not sufficient to completely explain the regulatory phenotype of these key players in autoimmunity and inflammation: after being activated, conventional human CD4(+) T cells transiently up-regulate FOXP3 without acquiring a regulatory function. Researchers have recently found that glycoprotein A repetitions predominant (GARP, or LRRC32) is a T(reg)-specific receptor that binds latent TGF-beta and dominantly controls FOXP3 and the regulatory phenotype via a positive feedback loop. This finding provides a missing link in our molecular understanding of FOXP3 in T(reg) cells. This viewpoint focuses on GARP as safeguard of FOXP3 and the regulatory phenotype.

EFFECTS OF HISTONE DEACETYLASE INHIBITOR, SAHA, ON EFFECTOR AND FOXP3+ REGULATORY T CELLS IN RHESUS MACAQUES

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Johnson, Jennifer; Pahuja, Anil; Graham, Melanie; Hering, Bernhard; Hancock, Wayne W.; Pratima, Bansal-Pakala

2008-01-01

SAHA, a histone deacetylase inhibitor (HDACi), is clinically approved for treatment of cutaneous T-cell lymphoma. Although the exact underlying mechanisms are unknown, HDACi arrest the cell cycle in rapidly proliferating tumor cells and promote their apoptosis. HDACi were also recently shown to enhance the production and suppressive functions of Foxp3+ regulatory T (Treg) cells in rodents, leading us to begin to investigate the actions of HDACi on rhesus monkey T cells for the sake of potential preclinical applications. In this study, we show that SAHA inhibits polyclonal activation and proliferation of rhesus T cells and that the anti-proliferative effects are due to inhibition of T effector (Teff) cells and enhancement of Treg cells. Cryopreserved rhesus macaque splenocytes were CFSE labeled, stimulated with anti-CD3/anti-CD28 and cultured for 5 days in the presence of varying concentrations of SAHA. Samples were then co-stained to evaluate CD4 and CD8 expression. 10 and 5μM concentrations of SAHA were toxic to splenocytes. Proliferation was inhibited by 57% in CD4 cells and 47% in CD8 cells when unseparated splenocytes were cultured with 3 μM SAHA. Effector cells alone showed a decreased inhibition to proliferation when cultured with 3 μM and 1 μM SAHA when compared to Teff plus Treg cells. Our data suggest that SAHA can be used as part of an immunosuppressive protocol to enhance graft survival by limiting Teff cell proliferation as well as increasing Treg cells, thereby promoting tolerance. PMID:18374101

Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP.

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Elkord, Eyad; Abd Al Samid, May; Chaudhary, Belal

2015-08-21

Regulatory T cells (Tregs) are key players of immune regulation/dysregulation both in physiological and pathophysiological settings. Despite significant advances in understanding Treg function, there is still a pressing need to define reliable and specific markers that can distinguish different Treg subpopulations. Herein we show for the first time that markers of activated Tregs [latency associated peptide (LAP) and glycoprotein A repetitions predominant (GARP, or LRRC32)] are expressed on CD4+FoxP3- T cells expressing Helios (FoxP3-Helios+) in the steady state. Following TCR activation, GARP/LAP are up-regulated on CD4+Helios+ T cells regardless of FoxP3 expression (FoxP3+/-Helios+). We show that CD4+GARP+/-LAP+ Tregs make IL-10 immunosuppressive cytokine but not IFN-γ effector cytokine. Further characterization of FoxP3/Helios subpopulations showed that FoxP3+Helios+ Tregs proliferate in vitro significantly less than FoxP3+Helios- Tregs upon TCR stimulation. Unlike FoxP3+Helios- Tregs, FoxP3+Helios+ Tregs secrete IL-10 but not IFN-γ or IL-2, confirming they are bona fide Tregs with immunosuppressive characteristics. Taken together, Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP, and FoxP3+Helios+ Tregs have more suppressive characteristics, compared with FoxP3+Helios- Tregs. Our work implies that therapeutic modalities for treating autoimmune and inflammatory diseases, allergies and graft rejection should be designed to induce and/or expand FoxP3+Helios+ Tregs, while therapies against cancers or infectious diseases should avoid such expansion/induction.

Differential expression of muscarinic acetylcholine receptor subtypes in Jurkat cells and their signaling.

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Alea, Mileidys Perez; Borroto-Escuela, Dasiel O; Romero-Fernandez, Wilber; Fuxe, Kjell; Garriga, Pere

2011-08-15

Muscarinic acetylcholine receptors expression and signaling in the human Jurkat T cell line were investigated. Semiquantitative real-time PCR and radioligand binding studies, using a wide set of antagonist compounds, showed the co-existence of M(3), M(4), and M(5) subtypes. Stimulation of these subpopulations caused a concentration and time- dependent activation of second messengers and ERK signaling pathways, with a major contribution of the M(3) subtype in a G(q/11)-mediated response. In addition, we found that T-cell stimulation leads to increased expression of M(3) and M(5) both at transcriptional and protein levels in a PLC/PKCθ dependent manner. Our data clarifies the functional role of AChR subtypes in Jurkat cells and pave the way to future studies on the potential cross-talk among these subpopulations and their regulation of T lymphocytes immune function. Copyright © 2011 Elsevier B.V. All rights reserved.

FOXP3 and GARP (LRRC32: the master and its minion

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Buer Jan

2010-02-01

Full Text Available Abstract The transcription factor FOXP3 is essential for the development and function of CD4+CD25hiFOXP3+ regulatory T (Treg cells, but also expressed in activated human helper T cells without acquisition of a regulatory phenotype. This comment focuses on glycoprotein-A repetitions predominant (GARP or LRRC32 recently identified as specific marker of activated human Treg cells, which may provide the missing link toward a better molecular definition of the regulatory phenotype. Reviewers: Dr Jim Di Danto, Dr Benedita Rocha and Dr Werner Solbach.

[ABIN1 is not involved in imatinib upregulating A20 to inhibit the activation of NF-κB pathway in Jurkat T cells].

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Chen, Qian; Wang, Senlin; Lin, Chen; Chen, Shaohua; Zhao, Xiaoling; Li, Yangqiu

2017-05-01

Objective To investigate the effect of imatinib (IM) on the expressions of A20-binding inhibitor of NF-κB1 (ABIN1) and A20 in Jurkat T cells. Methods Jurkat T cells were treated with 25, 50 and 100 nmol/L IM for 24 hours. The mRNA and protein levels of ABIN1, A20 and NF-κB were detected by real-time quantitative PCR and Western blotting. Results IM significantly inhibited both mRNA and protein levels of ABIN1 and NF-κB, but raised the mRNA and protein levels of A20; while phorbol 12-myristate 13-acetate/ionomycin increased the expression levels of ABIN1 and A20 mRNA and protein. Conclusion IM could upregulate A20 protein to inhibit the activation of NF-κB pathway in Jurkat T cells, which was independent of the ABIN1 protein.

Foxp3 Expression is Required for the Induction of Therapeutic Tissue Tolerance1

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Regateiro, Frederico S.; Chen, Ye; Kendal, Adrian R.; Hilbrands, Robert; Adams, Elizabeth; Cobbold, Stephen P.; Ma, Jianbo; Andersen, Kristian G.; Betz, Alexander G.; Zhang, Mindy; Madhiwalla, Shruti; Roberts, Bruce; Waldmann, Herman; Nolan, Kathleen F.; Howie, Duncan

2012-01-01

CD4+Foxp3+ Treg are essential for immune homeostasis and maintenance of self-tolerance. They are produced in the thymus and also generated de novo in the periphery in a TGFβ dependent manner. Foxp3+ Treg are also required to achieve tolerance to transplanted tissues when induced by co receptor or co stimulation blockade. Using TCR transgenic mice to avoid issues of autoimmune pathology, we show that Foxp3 expression is both necessary and sufficient for tissue tolerance by coreceptor blockade. Moreover, the known need in tolerance induction for TGFβ signalling to T cells can wholly be explained by its role in induction of Foxp3, as such signalling proved dispensable for the suppressive process. We analysed the relative contribution of TGFβ and Foxp3 to the transcriptome of TGFβ-induced Treg and showed that TGFβ elicited a large set of down-regulated signature genes. The number of genes uniquely modulated due to the influence of Foxp3 alone was surprisingly limited. Thus, despite the large genetic influence of TGFβ exposure on iTreg, the crucial Foxp3-influenced signature independent of TGFβ is small. Retroviral mediated conditional nuclear expression of Foxp3 proved sufficient to confer transplant-suppressive potency on CD4+ T cells, and was lost once nuclear Foxp3 expression was extinguished. These data support a dual role for TGFβ and Foxp3 in induced tolerance, where TGFβ stimulates Foxp3 expression, whose sustained expression is then associated with acquisition of tolerance. PMID:22988034

Activation-dependent mitochondrial translocation of Foxp3 in human hepatocytes

International Nuclear Information System (INIS)

Rojas, Joselyn; Teran-Angel, Guillermo; Barbosa, Luisa; Peterson, Darrell L.; Berrueta, Lisbeth; Salmen, Siham

2016-01-01

Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection. - Highlights: • The expression and subcellular distribution of Foxp3, is modulated by PMA and preS1/2. • PMA and preS1/2 increase Foxp3 expression on HepG2. • PMA and preS1/2 induce foxp3 enrichment at mitochondrial, microsomal and nuclear compartments. • Results suggest a non-canonical function of Foxp3 or a mitochondrial transcriptional activity.

Activation-dependent mitochondrial translocation of Foxp3 in human hepatocytes

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Rojas, Joselyn; Teran-Angel, Guillermo; Barbosa, Luisa [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Peterson, Darrell L. [Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA (United States); Berrueta, Lisbeth, E-mail: lberruet@ula.ve [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Division of Preventive Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Salmen, Siham, E-mail: sihamsa@ula.ve [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of)

2016-05-01

Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection. - Highlights: • The expression and subcellular distribution of Foxp3, is modulated by PMA and preS1/2. • PMA and preS1/2 increase Foxp3 expression on HepG2. • PMA and preS1/2 induce foxp3 enrichment at mitochondrial, microsomal and nuclear compartments. • Results suggest a non-canonical function of Foxp3 or a mitochondrial transcriptional activity.

Induction of T helper 3 regulatory cells by dendritic cells infected with porcine reproductive and respiratory syndrome virus

International Nuclear Information System (INIS)

Silva-Campa, Erika; Flores-Mendoza, Lilian; Resendiz, Monica; Pinelli-Saavedra, Araceli; Mata-Haro, Veronica; Mwangi, Waithaka; Hernandez, Jesus

2009-01-01

Delayed development of virus-specific immune response has been observed in pigs infected with the porcine reproductive and respiratory syndrome virus (PRRSV). Several studies support the hypothesis that the PRRSV is capable of modulating porcine immune system, but the mechanisms involved are yet to be defined. In this study, we evaluated the induction of T regulatory cells by PRRSV-infected dendritic cells (DCs). Our results showed that PRRSV-infected DCs significantly increased Foxp3 + CD25 + T cells, an effect that was reversible by IFN-α treatment, and this outcome was reproducible using two distinct PRRSV strains. Analysis of the expressed cytokines suggested that the induction of Foxp3 + CD25 + T cells is dependent on TGF-β but not IL-10. In addition, a significant up-regulation of Foxp3 mRNA, but not TBX21 or GATA3, was detected. Importantly, our results showed that the induced Foxp3 + CD25 + T cells were able to suppress the proliferation of PHA-stimulated PBMCs. The T cells induced by the PRRSV-infected DCs fit the Foxp3 + CD25 + T helper 3 (Th3) regulatory cell phenotype described in the literature. The induction of this cell phenotype depended, at least in part, on PRRSV viability because IFN-α treatment or virus inactivation reversed these effects. In conclusion, this data supports the hypothesis that the PRRSV succeeds to establish and replicate in porcine cells early post-infection, in part, by inducing Th3 regulatory cells as a mechanism of modulating the porcine immune system.

Docosahexaenoic acid and other fatty acids induce a decrease in pHi in Jurkat T-cells

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Aires, Virginie; Hichami, Aziz; Moutairou, Kabirou; Khan, Naim Akhtar

2003-01-01

Docosahexaenoic acid (DHA) induced rapid (t1/2=33 s) and dose-dependent decreases in pHi in BCECF-loaded human (Jurkat) T-cells. Addition of 5-(N,N-dimethyl)-amiloride, an inhibitor of Na+/H+ exchanger, prolonged DHA-induced acidification as a function of time, indicating that the exchanger is implicated in pHi recovery.Other fatty acids like oleic acid, arachidonic acid, eicosapentaenoic acid, but not palmitic acid, also induced a fall in pHi in these cells.To assess the role of calcium in t...

Impact of 5-aza-2'-deoxycytidine and epigallocatechin-3-gallate for induction of human regulatory T cells.

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Kehrmann, Jan; Tatura, Roman; Zeschnigk, Michael; Probst-Kepper, Michael; Geffers, Robert; Steinmann, Joerg; Buer, Jan

2014-07-01

The epigenetic regulation of transcription factor genes is critical for T-cell lineage specification. A specific methylation pattern within a conserved region of the lineage specifying transcription factor gene FOXP3, the Treg-specific demethylated region (TSDR), is restricted to regulatory T (Treg) cells and is required for stable expression of FOXP3 and suppressive function. We analysed the impact of hypomethylating agents 5-aza-2'-deoxycytidine and epigallocatechin-3-gallate on human CD4(+)  CD25(-) T cells for generating demethylation within FOXP3-TSDR and inducing functional Treg cells. Gene expression, including lineage-specifying transcription factors of the major T-cell lineages and their leading cytokines, functional properties and global transcriptome changes were analysed. The FOXP3-TSDR methylation pattern was determined by using deep amplicon bisulphite sequencing. 5-aza-2'-deoxycytidine induced FOXP3-TSDR hypomethylation and expression of the Treg-cell-specific genes FOXP3 and LRRC32. Proliferation of 5-aza-2'-deoxycytidine-treated cells was reduced, but the cells did not show suppressive function. Hypomethylation was not restricted to FOXP3-TSDR and expression of master transcription factors and leading cytokines of T helper type 1 and type 17 cells were induced. Epigallocatechin-3-gallate induced global DNA hypomethylation to a lesser extent than 5-aza-2'-deoxycitidine, but no relevant hypomethylation within FOXP3-TSDR or expression of Treg-cell-specific genes. Neither of the DNA methyltransferase inhibitors induced fully functional human Treg cells. 5-aza-2'-deoxycitidine-treated cells resembled Treg cells, but they did not suppress proliferation of responder cells, which is an essential capability to be used for Treg cell transfer therapy. Using a recently developed targeted demethylation technology might be a more promising approach for the generation of functional Treg cells. © 2014 John Wiley & Sons Ltd.

FOXP3 inhibits cancer stem cell self-renewal via transcriptional repression of COX2 in colorectal cancer cells.

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Liu, Shuo; Zhang, Cun; Zhang, Kuo; Gao, Yuan; Wang, Zhaowei; Li, Xiaoju; Cheng, Guang; Wang, Shuning; Xue, Xiaochang; Li, Weina; Zhang, Wei; Zhang, Yingqi; Xing, Xianghui; Li, Meng; Hao, Qiang

2017-07-04

Colon cancer stem cell (cCSC) is considered as the seed cell of colon cancer initiation and metastasis. Cyclooxygenase-2 (COX2), a downstream target of NFκB, is found to be essential in promoting cancer stem cell renewal. However, how COX2 is dysregulated in cCSCs is largely unknown. In this study, we found that the expression of transcription factor FOXP3 was much lower in the spheroids than that in the parental tumor cells. Overexpression of FOXP3 significantly decreased the numbers of spheres, reduced the side population. Accordingly, FOXP3 expression decreased the tumor size and weight in the xenograft model. The tumor inhibitory effects of FOXP3 were rarely seen when COX2 was additionally knocked down. Mechanically, FOXP3 transcriptionally repressed COX2 expression via interacting with and thus inhibiting p65 activity on the putative NFκB response elements in COX2 promoter. Taken together, we here revealed possible involvement of FOXP3 in regulating cCSC self-renewal via tuning COX2 expression, and thus providing a new target for the eradication of colon cancer stem cells.

FOXP3+ Tregs and B7-H1+/PD-1+ T lymphocytes co-infiltrate the tumor tissues of high-risk breast cancer patients: Implication for immunotherapy

International Nuclear Information System (INIS)

Ghebeh, Hazem; Barhoush, Eman; Tulbah, Asma; Elkum, Naser; Al-Tweigeri, Taher; Dermime, Said

2008-01-01

Recent studies have demonstrated a direct involvement of B7-H1, PD-1 and FOXP3 molecules in the immune escape of cancer. B7-H1 is an inhibitory molecule that binds to PD-1 on T lymphocytes, while FOXP3 is a marker for regulatory T cells (T regs ). We have previously demonstrated the association of B7-H1-expressing T infiltrating lymphocytes (TIL) with high-risk breast cancer patients while other studies reported the involvement of FOXP3+ T regs as a bad prognostic factor in breast tumors. Although the co-existence between the two types of cells has been demonstrated in vitro and animal models, their relative infiltration and correlation with the clinicopathological parameters of cancer patients have not been well studied. Therefore, we investigated TIL-expressing the B7-H1, PD-1, and FOXP3 molecules, in the microenvironment of human breast tumors and their possible association with the progression of the disease. Using immunohistochemistry, tumor sections from 62 breast cancer patients were co-stained for B7-H1, PD-1 and FOXP3 molecules and their expression was statistically correlated with factors known to be involved in the progression of the disease. A co-existence of B7-H1 + T lymphocytes and FOXP3 + T regs was evidenced by the highly significant correlation of these molecules (P < .0001) and their expression by different T lymphocyte subsets was clearly demonstrated. Interestingly, concomitant presence of FOXP3 + T regs , B7-H1 + and PD-1 + TIL synergistically correlated with high histological grade (III) (P < .001), estrogen receptor negative status (P = .017), and the presence of severe lymphocytic infiltration (P = .022). Accumulation of TIL-expressing such inhibitory molecules may deteriorate the immunity of high-risk breast cancer patients and this should encourage vigorous combinatorial immunotherapeutic approaches targeting T regs and B7-H1/PD-1 molecules

NK-like homeodomain proteins activate NOTCH3-signaling in leukemic T-cells

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Nagel, Stefan; Scherr, Michaela; MacLeod, Roderick AF; Venturini, Letizia; Przybylski, Grzegorz K; Grabarczyk, Piotr; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; Schmidt, Christian A; Drexler, Hans G

2009-01-01

Homeodomain proteins control fundamental cellular processes in development and in cancer if deregulated. Three members of the NK-like subfamily of homeobox genes (NKLs), TLX1, TLX3 and NKX2-5, are implicated in T-cell acute lymphoblastic leukemia (T-ALL). They are activated by particular chromosomal aberrations. However, their precise function in leukemogenesis is still unclear. Here we screened further NKLs in 24 T-ALL cell lines and identified the common expression of MSX2. The subsequent aim of this study was to analyze the role of MSX2 in T-cell differentiation which may be disturbed by oncogenic NKLs. Specific gene activity was examined by quantitative real-time PCR, and globally by expression profiling. Proteins were analyzed by western blot, immuno-cytology and immuno-precipitation. For overexpression studies cell lines were transduced by lentiviruses. Quantification of MSX2 mRNA in primary hematopoietic cells demonstrated higher levels in CD34+ stem cells as compared to peripheral blood cells and mature CD3+ T-cells. Furthermore, analysis of MSX2 expression levels in T-cell lines after treatment with core thymic factors confirmed their involvement in regulation. These results indicated that MSX2 represents an hematopoietic NKL family member which is downregulated during T-cell development and may functionally substituted by oncogenic NKLs. For functional analysis JURKAT cells were lentivirally transduced, overexpressing either MSX2 or oncogenic TLX1 and NKX2-5, respectively. These cells displayed transcriptional activation of NOTCH3-signaling, including NOTCH3 and HEY1 as analyzed by gene expression profiling and quantitative RT-PCR, and consistently attenuated sensitivity to gamma-secretase inhibitor as analyzed by MTT-assays. Furthermore, in addition to MSX2, both TLX1 and NKX2-5 proteins interacted with NOTCH-pathway repressors, SPEN/MINT/SHARP and TLE1/GRG1, representing a potential mechanism for (de)regulation. Finally, elevated expression of NOTCH3

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

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Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

Site-specific integration of CAR gene into Jurkat T cells with a linear close-ended AAV-based DNA vector for CAR-T engineering.

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Zhang, Yun; Liu, Xiaomei; Zhang, Jinju; Zhang, Chun

2016-09-01

To develop a site-specific integration strategy for CAR-T engineering by using a non-viral vector dependent on adeno-associated viral (AAV) genome, which tends to be integrated into AAVS1 site with the help of its Rep proteins. AAV-dependent vectors were produced in Sf9 cells. Structural analyses revealed the vector as covalently close-ended, linear duplex molecules, which was termed "CELiD" DNA. A plasmid CMV-Rep was constructed to express the integrases Rep78 and Rep68. Jurkat cells were co-electroporated with "CELiD" DNA and plasmid CMV-Rep in order to specifically integrate CAR gene into AAVS1 site. We examined 71 stably transfected Jurkat clones by nested PCR, sequencing and southern blotting, of which 30 clones bore CAR gene within AAVS1 site. The site-specific integration efficiency was nearly 42.2 %. The AAV-dependent vector preferentially integrated CAR into AAVS1 site, which could be further used in human T cell modification and enhance the security of CAR-T therapy.

Effect of Light Irradiation and Sex Hormones on Jurkat T Cells: 17β-Estradiol but Not Testosterone Enhances UVA-Induced Cytotoxicity in Jurkat Lymphocytes

Directory of Open Access Journals (Sweden)

Michael F. Angel

2005-04-01

Full Text Available In Eastern cultures, such as India, it is traditionally recommended that women but not men cover their heads while working in the scorching sun. The purpose of this pilot study was to determine whether there was any scientific basis for this cultural tradition. We examined the differential cytotoxic effects of ultraviolet A light (UVA on an established T cell line treated with female and male sex hormones. CD4+ Jurkat T cells were plated in 96 well plates at 2 x 106 cells/ml and treated with 17β-estradiol (EST or testosterone (TE. These cells were irradiated by UVA light with an irradiance of 170 J/cm2 for 15min at a distance of 6 cm from the surface of the 96-well plate. Controls included cells not treated with hormones or UVA. The effects of EST and TE were investigated between 1 and 20 ng/mL. Cytotoxicity by fluorescein-diacetate staining and COMET assay generating single strand DNA cleavage, tail length and tail moment measurements were examined. The effect of estrogen (5ng/mL on apoptosis and its mediators was further studied using DNA laddering and western blotting for bcl-2 and p53. We found that EST alone, without UVA, enhanced Jurkat T cell survival. However, EST exhibited a dose-related cytotoxicity in the presence of UVA; up to 28% at 20 ng/ml. TE did not alter UVA-induced cytotoxicity. Since TE did not alter cell viability in the presence of UVA further damaging studies were not performed. COMET assay demonstrated the harmful effects of EST in the presence of UVA while EST without UVA had no significant effect on the nuclear damage. Apoptosis was not present as indicated by the absence of DNA laddering on agarose gel electrophoresis at 5ng/ml EST or TE ± UVA. Western blot showed that estrogen down regulated bcl-2 independently of UVA radiation while p53 was down regulated in the presence of UVA treatment. EST and TE have differential effects on UVA-induced cytotoxicity in Jurkat T-lymphocyte which suggested that women

Three distinct domains contribute to nuclear transport of murine Foxp3.

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Wayne W Hancock

2009-11-01

Full Text Available Foxp3, a 47-kDa transcription factor, is necessary for the function of CD4+CD25+ regulatory T cells (Tregs, with an essential role in the control of self-reactive T cells and in preventing autoimmunity. Activation of Tregs by TCR engagement results in upregulation of Foxp3 expression, followed by its rapid nuclear transport and binding to chromatin. Here, we identify three distinct Foxp3 domains that contribute to nuclear transport. The first domain (Domain 1 comprises the C-terminal 12 amino acids. The second domain (Domain 2 is located immediately N-terminal to the forkhead domain (FHD, recently reported to be a binding site for the runt-related transcription factor 1/acute myeloid leukemia 1 (Runx1/AML1. The third domain (Domain 3 is located within the N-terminal first 51 amino acids. Unlike the known nuclear localization signals (NLSs, none of these three regions are rich in basic residues and do not bear any similarity to known monopartite or bipartite NLSs that have one or more clusters of basic amino acids. The basic arginine-lysine-lysine-arginine (RKKR sequence, located 12-aa from the C-terminal end of Foxp3 was previously reported to be a nuclear localization signal (NLS for several proteins, including for a GFP-Foxp3 hybrid. Evidence is provided here that in the full-length native Foxp3 RKKR does not function as an NLS. The data reported in this study indicates that Foxp3 achieves nuclear transport by binding to other nuclear factors and co-transporting with them to the nucleus.

Nonoverlapping roles of PD-1 and FoxP3 in maintaining immune tolerance in a novel autoimmune pancreatitis mouse model.

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Zhang, Baihao; Chikuma, Shunsuke; Hori, Shohei; Fagarasan, Sidonia; Honjo, Tasuku

2016-07-26

PD-1 (programmed-death 1), an immune-inhibitory receptor required for immune self-tolerance whose deficiency causes autoimmunity with variable severity and tissue specificity depending on other genetic factors, is expressed on activated T cells, including the transcription factor FoxP3(+) Treg cells known to play critical roles in maintaining immune tolerance. However, whether PD-1 expression by the Treg cells is required for their immune regulatory function, especially in autoimmune settings, is still unclear. We found that mice with partial FoxP3 insufficiency developed early-onset lympho-proliferation and lethal autoimmune pancreatitis only when PD-1 is absent. The autoimmune phenotype was rescued by the transfer of FoxP3-sufficient T cells, regardless of whether they were derived from WT or PD-1-deficient mice, indicating that Treg cells dominantly protect against development of spontaneous autoimmunity without intrinsic expression of PD-1. The absence of PD-1 combined with partial FoxP3 insufficiency, however, led to generation of ex-FoxP3 T cells with proinflammatory properties and expansion of effector/memory T cells that contributed to the autoimmune destruction of target tissues. Altogether, the results suggest that PD-1 and FoxP3 work collaboratively in maintaining immune tolerance mostly through nonoverlapping pathways. Thus, PD-1 is modulating the activation threshold and maintaining the balance between regulatory and effector T cells, whereas FoxP3 is sufficient for dominant regulation through maintaining the integrity of the Treg function. We suggest that genetic or environmental factors that even moderately affect the expression of both PD-1 and FoxP3 can cause life-threatening autoimmune diseases by disrupting the T-cell homeostasis.

Peripherally Generated Foxp3+ Regulatory T Cells Mediate the Immunomodulatory Effects of IVIg in Allergic Airways Disease.

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Massoud, Amir H; Kaufman, Gabriel N; Xue, Di; Béland, Marianne; Dembele, Marieme; Piccirillo, Ciriaco A; Mourad, Walid; Mazer, Bruce D

2017-04-01

IVIg is widely used as an immunomodulatory therapy. We have recently demonstrated that IVIg protects against airway hyperresponsiveness (AHR) and inflammation in mouse models of allergic airways disease (AAD), associated with induction of Foxp3 + regulatory T cells (Treg). Using mice carrying a DTR/EGFP transgene under the control of the Foxp3 promoter (DEREG mice), we demonstrate in this study that IVIg generates a de novo population of peripheral Treg (pTreg) in the absence of endogenous Treg. IVIg-generated pTreg were sufficient for inhibition of OVA-induced AHR in an Ag-driven murine model of AAD. In the absence of endogenous Treg, IVIg failed to confer protection against AHR and airway inflammation. Adoptive transfer of purified IVIg-generated pTreg prior to Ag challenge effectively prevented airway inflammation and AHR in an Ag-specific manner. Microarray gene expression profiling of IVIg-generated pTreg revealed upregulation of genes associated with cell cycle, chromatin, cytoskeleton/motility, immunity, and apoptosis. These data demonstrate the importance of Treg in regulating AAD and show that IVIg-generated pTreg are necessary and sufficient for inhibition of allergen-induced AAD. The ability of IVIg to generate pure populations of highly Ag-specific pTreg represents a new avenue to study pTreg, the cross-talk between humoral and cellular immunity, and regulation of the inflammatory response to Ags. Copyright © 2017 by The American Association of Immunologists, Inc.

Increased level of both CD4+FOXP3+ regulatory T cells and CD14+HLA-DR⁻/low myeloid-derived suppressor cells and decreased level of dendritic cells in patients with multiple myeloma

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Brimnes, Marie Klinge; Vangsted, Annette Juul; Meldgaard Knudsen, Lene

2010-01-01

+FOXP3+ Treg cells was increased in patients at diagnosis and not in patients in remission or with MGUS. Also, Treg cells from patients with MM were functionally intact as they were able to inhibit proliferation of both CD4 and CD8 T cells. Finally, we observed an increase in the proportion of CD14+HLA-DR...... as a consequence of the disease....

Forkhead-Box-P3 Gene Transfer in Human CD4+ T Conventional Cells for the Generation of Stable and Efficient Regulatory T Cells, Suitable for Immune Modulatory Therapy

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Laura Passerini

2017-10-01

Full Text Available The development of novel approaches to control immune responses to self- and allogenic tissues/organs represents an ambitious goal for the management of autoimmune diseases and in transplantation. Regulatory T cells (Tregs are recognized as key players in the maintenance of peripheral tolerance in physiological and pathological conditions, and Treg-based cell therapies to restore tolerance in T cell-mediated disorders have been designed. However, several hurdles, including insufficient number of Tregs, their stability, and their antigen specificity, have challenged Tregs clinical applicability. In the past decade, the ability to engineer T cells has proven a powerful tool to redirect specificity and function of different cell types for specific therapeutic purposes. By using lentivirus-mediated gene transfer of the thymic-derived Treg transcription factor forkhead-box-P3 (FOXP3 in conventional CD4+ T cells, we converted effector T cells into Treg-like cells, endowed with potent in vitro and in vivo suppressive activity. The resulting CD4FOXP3 T-cell population displays stable phenotype and suppressive function. We showed that this strategy restores Treg function in T lymphocytes from patients carrying mutations in FOXP3 [immune-dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX], in whom CD4FOXP3 T cell could be used as therapeutics to control autoimmunity. Here, we will discuss the potential advantages of using CD4FOXP3 T cells for in vivo application in inflammatory diseases, where tissue inflammation may undermine the function of natural Tregs. These findings pave the way for the use of engineered Tregs not only in IPEX syndrome but also in autoimmune disorders of different origin and in the context of stem cell and organ transplantation.

Calycosin Inhibits the Migration and Invasion of Human Breast Cancer Cells by Down-Regulation of Foxp3 Expression

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Shuangxi Li

2017-12-01

Full Text Available Background/Aims: Calycosin, a phytoestrogenic compound, has recently emerged as a promising antitumor drug. It has been shown that calycosin suppresses growth and induces apoptosis of breast cancer cells. However, the effect of calycosin on migration and invasion of breast cancer cells and the underlying molecular mechanisms have not been elucidated. Methods: Human breast cancer cells MCF-7 and T47D were treated with, or without, different doses (0, 6.25, 12.5, 25, 50, 100 or 150 μM of calycosin, and the viability of different groups was determined by MTT assay. Next, the inhibitory effect of higher doses (50, 100 or 150 μM of calycosin on migration and invasion of the two cell lines was determined by wound healing and transwell assay. The relative expression levels of forkhead box P3 (Foxp3, vascular endothelial growth factor (VEGF and matrix metalloproteinase-9 (MMP-9 in MCF-7 and T47D cells were determined by quantitative RT-PCR and Western blot. Results: Treatment with lower doses (6.25 or 12.5 μM promoted proliferation of breast cancer cells, but with higher doses significantly reduced the viability of MCF-7 and T47D cells. Furthermore, higher doses of calycosin were found to inhibit migration and invasion of the two cell lines in a dose-dependent manner. Additionally, treatment with a higher dose of calycosin significantly reduced the expression levels of Foxp3, followed by down-regulation of VEGF and MMP-9 in both MCF-7 and T47D breast cancer cells. Conclusion: Treatment with a higher dose of calycosin tends to reduce migration and invasion capacity of human breast cancer cells, by targeting Foxp3-mediated VEGF and MMP-9 expression.

GARP (LRRC32) is essential for the surface expression of latent TGF-β on platelets and activated FOXP3+ regulatory T cells

OpenAIRE

Tran, Dat Q.; Andersson, John; Wang, Rui; Ramsey, Heather; Unutmaz, Derya; Shevach, Ethan M.

2009-01-01

TGF-β family members are highly pleiotropic cytokines with diverse regulatory functions. TGF-β is normally found in the latent form associated with latency-associated peptide (LAP). This latent complex can associate with latent TGFβ-binding protein (LTBP) to produce a large latent form. Latent TGF-β is also found on the surface of activated FOXP3+ regulatory T cells (Tregs), but it is unclear how it is anchored to the cell membrane. We show that GARP or LRRC32, a leucine-rich repeat molecule ...

Effect of cell density and HLA-DR incompatibility on T-cell proliferation and forkhead box P3 expression in human mixed lymphocyte reaction.

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Song, E Y; Han, S; Yang, B; Morris, G P; Bui, J D

2015-04-01

The proliferation rates of human T cells in vitro are affected by some factors such as initial T-cell number, dose of stimulating cells, and duration of culture. The transcription factor forkhead box P3 (FoxP3) has been used to identify regulatory T cells in humans and is thought to correlate with tolerance to allogeneic organ transplant. Thus, it is important to optimize conditions to expand FoxP3 cell proliferation to improve engraftment of allogeneic organ transplants. We studied proliferative responses and FoxP3 expression in divided T cells with the use of flow cytometric analysis of Ki-67 in culture of different concentrations of responding cells (6 × 10(6), 4 × 10(6), 2 × 10(6), 1 × 10(6), and 0.5 × 10(6)cells/mL), different types of stimulating cells (lymphocytes and low density cells), and different numbers of HLA mismatches. The proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells among mononuclear cells were highest at initial cell concentration of 2 × 10(6) responder cells/mL with lymphocytes as stimulators at day-5 mixed lymphocyte reaction (MLR). They were highest at a concentration of 4 × 10(6) responder cells/mL with low density cells as stimulators. The recovery (%), proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells with 2 HLA-DR incompatibility were significantly higher than those of 1 HLA-DR incompatibility at day-5 MLR. Initial cell concentration and HLA-DR incompatibility can affect the generation of FoxP3+ T cells in human MLR. These factors could be considered for efficient generation of Tregs for clinical trials in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

Silencing of Foxp3 delays the growth of murine melanomas and modifies the tumor immunosuppressive environment

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Franco-Molina MA

2016-01-01

Full Text Available Moisés A Franco-Molina,* Diana F Miranda-Hernández,* Edgar Mendoza-Gamboa, Pablo Zapata-Benavides, Erika E Coronado-Cerda, Crystel A Sierra-Rivera, Santiago Saavedra-Alonso, Reyes S Taméz-Guerra, Cristina Rodríguez-Padilla Immunology and Virology Department, Biological Sciences Faculty, University Autonoma of Nuevo León (UANL, San Nicolás de los Garza, Nuevo León, Mexico*These authors contributed equally to this work Abstract: Forkhead box p3 (Foxp3 expression was believed to be specific for T-regulatory cells but has recently been described in non-hematopoietic cells from different tissue origins and in tumor cells from both epithelial and non-epithelial tissues. The aim of this study was to elucidate the role of Foxp3 in murine melanoma. The B16F10 cell line Foxp3 silenced with small interference Foxp3 plasmid transfection was established and named B16F10.1. These cells had lower levels of Foxp3 mRNA (quantitative real-time reverse transcription-polymerase chain reaction [0.235-fold], protein (flow cytometry [0.02%], CD25+ expression (0.06%, cellular proliferation (trypan blue staining, and interleukin (IL-2 production (enzyme-linked immunosorbent assay [72.35 pg/mL] than those in B16F10 wild-type (WT cells (P<0.05. Subcutaneous inoculation of the B16F10.1 cell line into C57BL/6 mice delayed the time of visible tumor appearance, increased the time of survival, and affected the weight of tumors, and also decreased the production of IL-10, IL-2, and transforming growth factor beta compared with mice inoculated with the B16F10 WT cell line. The B16F10.1 cells derived from tumors and free of T-cells (isolated by Dynabeads and plastic attachment expressed relatively lower levels of Foxp3 and CD25+ than B16F10 WT cells (P<0.05 in a time-dependent manner. The population of tumor-infiltrating lymphocytes of T CD4+ cells (CD4+, CD4+CD25+, and CD4+CD25+Foxp3+ increased in a time-dependent manner (P<0.05 in tumors derived from B16F10 WT cells

TOM1L Is Involved in a Novel Signaling Pathway Important for the IL-2 Production in Jurkat T Cells Stimulated by CD3/CD28 CoLigation

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Ahmed Elmarghani

2009-01-01

Full Text Available TOM1L (target of Myb-1 Like was identified as a binding partner for the full length and catalytically-active Lck in a yeast 2-hybrid screening assay. Here we show that in Jurkat T cells stimulated by CD3/CD28 coligation where the expression of TOM1L is reduced by lenti virus mediated-siRNA results in a dramatically lower IL-2 production. The production of IL-2 in siRNA treated cells stimulated with PMA/ionomycin was not affected indicating an involvement of TOM1L in a pathway proximal of TCR and CD28. The coexpression of Fyn with TOM1L increased the level of the phosphorylated form of Fyn indicating that TOM1L has the ability to activate Fyn. The ability of TOM1L to activate Fyn was further shown in a kinase assay using angiotensin II as a substrate. By confocal microscopy, we show that the expression of TOM1L in non-treated HeLa and SK-N-SH cells colocalizes with the mitochondrial membrane but not with lysosomal compartments or the trans-Golgi network. Furthermore, we show that the over-expression of TOM1L in Jurkat cells causes an increase of the STAT3 expression . Based on our results, we here propose that TOM1L is involved in a novel signaling pathway that is important for the IL-2 production in T cells.

Association of aplastic anemia and FoxP3 gene polymorphisms in Koreans.

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In, Ji Won; Lee, Nuri; Roh, Eun Youn; Shin, Sue; Park, Kyoung Un; Song, Eun Young

2017-04-01

Aplastic anemia (AA) is characterized by pancytopenia and bone marrow failure, and most acquired AA is an immune-mediated disorder. Regulatory T cells (T regs ) suppressing autoreactive T cells were decreased in AA patients. FoxP3 is a major regulator for the development and function of T regs . Polymorphism in FoxP3 was shown to be associated with various autoimmune diseases, however, has not yet been studied in AA. In this study, we examined the association between FoxP3 polymorphisms and AA in Korean patients. The study population consisted of 94 patients diagnosed by bone marrow examination in Seoul National University Hospital (SNUH) during 1997-2012 and 195 healthy controls. FoxP3 polymorphisms (rs5902434 del/ATT, rs3761548 C/A, rs3761549 C/T, rs2232365 A/G) were analyzed by PCR-sequencing method. We analyzed differences of genotype and allele frequencies between patients and controls. We also compared differences of genotype and allele frequencies between responder and non-responder in patients treated with immunosuppressive therapy (IST). For the statistical analysis, the chi-square test and Fisher's exact test were used and P < 0.05 was regarded as statistically significant. There was no significant difference in the genotype frequencies of FoxP3 polymorphisms between patients and controls. With regards to the allele frequencies, rs3761548 C allele was significantly higher in AA patients than in controls (87.4% vs. 79.7%, P = 0.047). In patients treated with IST, rs3761549 C allele was significantly higher in non-responder patients than in responders (89.6% vs. 66.7%, P = 0.036) and female rs3761549 C/C genotype carriers were associated with greater risk for non-response to IST (84.2% vs. 16.7%, P = 0.006). Polymorphisms in rs3761548 and rs3761549 of FoxP3 in our population were associated with disease susceptibility and response for IST, respectively. This study suggests an association between FoxP3 polymorphisms and AA in Korean patients

Polysaccharide Isolated from Zizyphus jujuba (紅棗 Hóng Zǎo Inhibits Interleukin-2 Production in Jurkat T Cells

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Bo-Yang Hsu

2014-04-01

Full Text Available Zizyphus jujuba (紅棗 Hóng Zǎo, a traditional Chinese herb widely used in many Asian countries, has been shown to possess vital biological activities such as anti-cancer activity. The objective of this study was to evaluate the immunomodulatory effect of deproteinated polysaccharide (DP isolated from Z. jujuba. The DP isolated from Z. jujuba consisted of two polysaccharide fractions and their molecular weights (MWs were found to be 143,108 and 67,633 Da, respectively. The DP could significantly decrease interleukin (IL-2 production in phytohemagglutinin (PHA-activated Jurkat T cells in a dose-dependent manner after 48 h of incubation, with the inhibition being 47.5%, 61.2%, and 81.7% for DP concentrations of 0.75, 1.75, and 2.5 mg/ml, respectively. Thus, our study showed that DP isolated from Z. jujuba may possess anti-inflammatory activity as it could significantly reduce IL-2 production in activated Jurkat T cells.

Femtograms of Interferon-γ Suffice to Modulate the Behavior of Jurkat Cells: A New Light in Immunomodulation

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Sara Castiglioni

2017-12-01

Full Text Available Since interferon-γ (IFN-γ tunes both innate and adaptive immune systems, it was expected to enter clinical practice as an immunomodulatory drug. However, the use of IFN-γ has been limited by its dose-dependent side effects. Low-dose medicine, which is emerging as a novel strategy to treat diseases, might circumvent this restriction. Several clinical studies have proved the efficacy of therapies with a low dose of cytokines subjected to kinetic activation, while no in vitro data are available. To fill this gap, we investigated whether low concentrations, in the femtogram range, of kinetically activated IFN-γ modulate the behavior of Jurkat cells, a widely used experimental model that has importantly contributed to the present knowledge about T cell signaling. In parallel, IFN-γ in the nanogram range was used and shown to activate Signal transducer and activator of transcription (STAT-1 and then to induce suppressor of cytokine signaling-1 (SOCS-1, which inhibits downstream signaling. When added together, femtograms of IFN-γ interfere with the transduction cascade activated by nanograms of IFN-γ by prolonging the activation of STAT-1 through the downregulation of SOCS-1. We conclude that femtograms of IFN-γ exert an immunomodulatory action in Jurkat cells.

Increase of circulating CD4+CD25highFoxp3+ regulatory T cells in patients with metastatic renal cell carcinoma during treatment with dendritic cell vaccination and low-dose interleukin-2

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Berntsen, Annika; Brimnes, Marie Klinge; thor Straten, Per

2010-01-01

Regulatory T cells (Treg) play an important role in the maintenance of immune tolerance and may be one of the obstacles of successful tumor immunotherapy. In this study, we analyzed the impact of administration of dendritic cell (DC) vaccination in combination with low-dose interleukin (IL)-2...... in patients with metastatic renal cell carcinoma on the frequency of CD4+CD25highFoxp3+ Treg cells in peripheral blood. We found that the treatment increased the frequency of Treg cells more than 7-fold compared with pretreatment levels (P...

Resolving Early Signaling Events in T-Cell Activation Leading to IL-2 and FOXP3 Transcription

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Jeffrey P. Perley

2014-11-01

Full Text Available Signal intensity and feedback regulation are known to be major factors in the signaling events stemming from the T-cell receptor (TCR and its various coreceptors, but the exact nature of these relationships remains in question. We present a mathematical model of the complex signaling network involved in T-cell activation with cross-talk between the Erk, calcium, PKC and mTOR signaling pathways. The model parameters are adjusted to fit new and published data on TCR trafficking, Zap70, calcium, Erk and Isignaling. The regulation of the early signaling events by phosphatases, CD45 and SHP1, and the TCR dynamics are critical to determining the behavior of the model. Additional model corroboration is provided through quantitative and qualitative agreement with experimental data collected under different stimulating and knockout conditions. The resulting model is analyzed to investigate how signal intensity and feedback regulation affect TCR- and coreceptor-mediated signal transduction and their downstream transcriptional profiles to predict the outcome for a variety of stimulatory and knockdown experiments. Analysis of the model shows that: (1 SHP1 negative feedback is necessary for preventing hyperactivity in TCR signaling; (2 CD45 is required for TCR signaling, but also partially suppresses it at high expression levels; and (3 elevated FOXP3 and reduced IL-2 signaling, an expression profile often associated with T regulatory cells (Tregs, is observed when the system is subjected to weak TCR and CD28 costimulation or a severe reduction in CD45 activity.

Long term follow up of patients after allogeneic stem cell transplantation and transfusion of HSV-Tk transduced T-cells.

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Eva Maria Weissinger

2015-04-01

Full Text Available Allogeneic stem cell transplantation (allo-HSCT is one of the curative treatments for hematologic malignancies, but is hampered by severe complications, such as acute or chronic graft-versus-host-disease (aGvHD; cGvHD and infections. CD34-selcetion of stem cells reduces the risk of aGvHD, but also leads to increased infectious complications and relapse. Thus, we studied the efficacy, safety and feasibility of transfer of gene modified donor T-cells shortly after allo-HSCT in two clinical trials between 2002 and 2007 and here we compare the results to unmodified donor leukocyte transfusion (DLI. The aim of these trials was to provide patients with the protection of T-cells after T-cell-depleted allo-HSCT in the matched or mismatched donor setting with an option to delete transduced T-cells, if severe aGvHD occurred within the trial period. Donor-T-cells were transduced with the replication-deficient retrovirus SFCMM-3, expressing HSV-Tk and the truncated LNGFR for selection of transduced cells. Transduced cells were transfused either after day +60 (matched donors or on day +42 (haploidentical donors.Nine patients were included in the first trial (MHH; 2002 until 2007 2 were included in TK007 (2005-2009 and 6 serve as a control group for outcome after haploidentical transplantation without HSV-TK-transduced DLI. Three patients developed acute GvHD, two had grade I of the skin, one had aGvHD on day +131 (post-HSCT; +89 post-HSV-Tk DLI grade II, which was successfully controlled by ganciclovir (GCV. Donor chimerism was stabilized after transfusion of the transduced cells in all patients treated. Functionality of HSV-Tk gene expressing T-cells was shown by loss of bcr-abl gene expression as well as by control of cytomegalovirus-reactivation. To date, 6patients have relapsed and died, 2 after a second HSCT without T-cell depletion or administration of unmodified T-cells. Eleven patients (7 post-HSV-Tk DLI are alive and well to date.

Expression of full-length and splice forms of FoxP3 in rheumatoid arthritis

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Ryder, L R; Woetmann, A; Madsen, H O

2010-01-01

OBJECTIVE: The aim of our study was to compare the presence of full-length and alternative splice forms of FoxP3 mRNA in CD4 cells from rheumatoid arthritis (RA) patients and healthy controls. METHODS: A quantitative real-time polymerase chain reaction (QRT-PCR) method was used to measure...... the amount of FoxP3 mRNA full-length and splice forms. CD4-positive T cells were isolated from peripheral blood from 50 RA patients by immunomagnetic separation, and the FoxP3 mRNA expression was compared with the results from 10 healthy controls. RESULTS: We observed an increased expression of full......-length FoxP3 mRNA in RA patients when compared to healthy controls, as well as an increase in CD25 mRNA expression, but no corresponding increase in CTLA-4 mRNA expression. The presence of an alternative splice form of FoxP3 lacking exon 2 was confirmed in both RA patients and healthy controls...

Kaempferol enhances the suppressive function of Treg cells by inhibiting FOXP3 phosphorylation.

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Lin, Fang; Luo, Xuerui; Tsun, Andy; Li, Zhiyuan; Li, Dan; Li, Bin

2015-10-01

Kaempferol is a natural flavonoid found in many vegetables and fruits. Epidemiologic studies have described that Kaempferol intake could reduce risk of cancer, especially lung, gastric, pancreatic and ovarian cancers. Recent studies have shown that Kaempferol could also be beneficial to the body to defend against inflammation, and infection by bacteria and viruses; however, the molecular mechanism of its immunoregulatory function remains largely unknown. Through screening a small molecule library of traditional Chinese medicine (TCM), we identified that Kaempferol could enhance the suppressive function of regulatory T cells (Tregs). Kaempferol was found to increase FOXP3 expression level in Treg cells and prevent pathological symptoms of collagen-induced arthritis in a rat animal model. Kaempferol could also reduce PIM1-mediated FOXP3 phosphorylation at S422. Our study reveals a molecular mechanism that underlies the anti-inflammatory action of Kaempferol for the prevention and treatment of inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus, and ankylosing spondylitis. Copyright © 2015 Elsevier B.V. All rights reserved.

A Trichostatin A (TSA)/Sp1-mediated mechanism for the regulation of SALL2 tumor suppressor in Jurkat T cells.

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Hepp, Matías I; Escobar, David; Farkas, Carlos; Hermosilla, Viviana; Álvarez, Claudia; Amigo, Roberto; Gutiérrez, José L; Castro, Ariel F; Pincheira, Roxana

2018-05-17

SALL2 is a transcription factor involved in development and disease. Deregulation of SALL2 has been associated with cancer, suggesting that it plays a role in the disease. However, how SALL2 is regulated and why is deregulated in cancer remain poorly understood. We previously showed that the p53 tumor suppressor represses SALL2 under acute genotoxic stress. Here, we investigated the effect of Histone Deacetylase Inhibitor (HDACi) Trichostatin A (TSA), and involvement of Sp1 on expression and function of SALL2 in Jurkat T cells. We show that SALL2 mRNA and protein levels were enhanced under TSA treatment. Both, TSA and ectopic expression of Sp1 transactivated the SALL2 P2 promoter. This transactivation effect was blocked by the Sp1-binding inhibitor mithramycin A. Sp1 bound in vitro and in vivo to the proximal region of the P2 promoter. TSA induced Sp1 binding to the P2 promoter, which correlated with dynamic changes on H4 acetylation and concomitant recruitment of p300 or HDAC1 in a mutually exclusive manner. Our results suggest that TSA-induced Sp1-Lys703 acetylation contributes to the transcriptional activation of the P2 promoter. Finally, using a CRISPR/Cas9 SALL2-KO Jurkat-T cell model and gain of function experiments, we demonstrated that SALL2 upregulation is required for TSA-mediated cell death. Thus, our study identified Sp1 as a novel transcriptional regulator of SALL2, and proposes a novel epigenetic mechanism for SALL2 regulation in Jurkat-T cells. Altogether, our data support SALL2 function as a tumor suppressor, and SALL2 involvement in cell death response to HDACi. Copyright © 2018. Published by Elsevier B.V.

4-1BB Signaling in Conventional T Cells Drives IL-2 Production That Overcomes CD4+CD25+FoxP3+ T Regulatory Cell Suppression.

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Hampartsoum B Barsoumian

Full Text Available Costimulation with the recombinant SA-4-1BBL agonist of 4-1BB receptor on conventional CD4+ T cells (Tconvs overcomes the suppression mediated by naturally occurring CD4+CD25+FoxP3+ T regulatory cells (Tregs. The mechanistic basis of this observation has remained largely unknown. Herein we show that Tconvs, but not Tregs, are the direct target of SA-4-1BBL-mediated evasion of Treg suppression. IL-2 produced by Tconvs in response to 4-1BB signaling is both necessary and sufficient for overcoming Treg suppression. Supernatant from Tconvs stimulated with SA-4-1BBL contains high levels of IL-2 and overcomes Treg suppression in ex vivo Tconv:Treg cocultures. Removal of IL-2 from such supernatant restores Treg suppression and repletion of Tconv:Treg cocultures with exogenous recombinant IL-2 overcomes suppression. This study establishes 4-1BB signaling as a key circuit that regulates physical and functional equilibrium between Tregs and Tconvs with important implications for immunotherapy for indications where a fine balance between Tregs and Teffs plays a decisive role.

Novel insights into the antiproliferative effects and synergism of quercetin and menadione in human leukemia Jurkat T cells.

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Baran, Irina; Ionescu, Diana; Filippi, Alexandru; Mocanu, Maria Magdalena; Iftime, Adrian; Babes, Ramona; Tofolean, Ioana Teodora; Irimia, Ruxandra; Goicea, Alexandru; Popescu, Valentin; Dimancea, Alexandru; Neagu, Andrei; Ganea, Constanta

2014-07-01

The flavonoid quercetin and menadione (vitamin K3) are known as potent apoptogens in human leukemia Jurkat T cells. We explored some underlying mechanisms and the potential relevance of the combination quercetin-menadione for clinical applications. In acute treatments, quercetin manifested a strong antioxidant character, but induced a transient loss of Δψm, likely mediated by opening of the mitochondrial permeability transition pore. After removal of quercetin, persistent mitochondrial hyperpolarization was generated via stimulation of respiratory Complex I. In contrast, menadione-induced Δψm dissipation was only partially and transiently reversed after menadione removal. Results indicate that Ca(2+) release is a necessary event in quercetin-induced cell death and that the survival response to quercetin is delineated within 1h from exposure. Depending on dose, the two agents exhibited either antagonistic or synergistic effects in reducing clonogenicity of Jurkat cells. 24-h combinatorial regimens at equimolar concentrations of 10-15 μM, which are compatible with a clinically achievable (and safe) scheme, reduced cell viability at efficient rates. Altogether, these findings support the idea that the combination quercetin-menadione could improve the outcome of conventional leukemia therapies, and warrant the utility of additional studies to investigate the therapeutic effects of this combination in different cellular or animal models for leukemia. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Biology of Autoimmune Response in the Scurfy Mice that Lack the CD4+Foxp3+ Regulatory T-Cells.

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Ju, Shyr-Te; Sharma, Rahul; Gaskin, Felicia; Kung, John T; Fu, Shu Man

2012-04-04

Due to a mutation in the Foxp3 transcription factor, Scurfy mice lack regulatory T-cells that maintain self-tolerance of the immune system. They develop multi-organ inflammation (MOI) and die around four weeks old. The affected organs are skin, tail, lungs and liver. In humans, endocrine and gastrointestinal inflammation are also observed, hence the disease is termed IPEX (Immunodysregulation, Polyendocrinopathy, Enteropathy, X-linked) syndrome. The three week period of fatal MOI offers a useful autoimmune model in which the controls by genetics, T-cell subsets, cytokines, and effector mechanisms could be efficiently investigated. In this report, we will review published work, summarize our recent studies of Scurfy double mutants lacking specific autoimmune-related genes, discuss the cellular and cytokine controls by these genes on MOI, the organ-specificities of the MOI controlled by environments, and the effector mechanisms regulated by specific Th cytokines, including several newly identified control mechanisms for organ-specific autoimmune response.

Perspectives on Regulatory T Cell Therapies.

Science.gov (United States)

Probst-Kepper, Michael; Kröger, Andrea; Garritsen, Henk S P; Buer, Jan

2009-01-01

Adoptive transfer in animal models clearly indicate an essential role of CD4+ CD25+ FOXP3+ regulatory T (T(reg)) cells in prevention and treatment of autoimmune and graft-versus-host disease. Thus, T(reg) cell therapies and development of drugs that specifically enhance T(reg) cell function and development represent promising tools to establish dominant tolerance. So far, lack of specific markers to differentiate human T(reg) cells from activated CD4+ CD25+ effector T cells, which also express FOXP3 at different levels, hampered such an approach. Recent identification of the orphan receptor glycoprotein-A repetitions predominant (GARP or LRRC32) as T(reg) cell-specific key molecule that dominantly controls FOXP3 via a positive feedback loop opens up new perspectives for molecular and cellular therapies. This brief review focuses on the role of GARP as a safeguard of a complex regulatory network of human T(reg) cells and its implications for regulatory T cell therapies in autoimmunity and graft-versus-host disease.

Foxp1 controls mature B cell survival and the development of follicular and B-1 B cells

Science.gov (United States)

Patzelt, Thomas; Keppler, Selina J.; Gorka, Oliver; Thoene, Silvia; Wartewig, Tim; Reth, Michael; Förster, Irmgard; Lang, Roland; Buchner, Maike; Ruland, Jürgen

2018-01-01

The transcription factor Foxp1 is critical for early B cell development. Despite frequent deregulation of Foxp1 in B cell lymphoma, the physiological functions of Foxp1 in mature B cells remain unknown. Here, we used conditional gene targeting in the B cell lineage and report that Foxp1 disruption in developing and mature B cells results in reduced numbers and frequencies of follicular and B-1 B cells and in impaired antibody production upon T cell-independent immunization in vivo. Moreover, Foxp1-deficient B cells are impaired in survival even though they exhibit an increased capacity to proliferate. Transcriptional analysis identified defective expression of the prosurvival Bcl-2 family gene Bcl2l1 encoding Bcl-xl in Foxp1-deficient B cells, and we identified Foxp1 binding in the regulatory region of Bcl2l1. Transgenic overexpression of Bcl2 rescued the survival defect in Foxp1-deficient mature B cells in vivo and restored peripheral B cell numbers. Thus, our results identify Foxp1 as a physiological regulator of mature B cell survival mediated in part via the control of Bcl-xl expression and imply that this pathway might contribute to the pathogenic function of aberrant Foxp1 expression in lymphoma. PMID:29507226

Helminth antigens enable CpG-activated dendritic cells to inhibit the symptoms of collagen-induced arthritis through Foxp3+ regulatory T cells.

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Franco Carranza

Full Text Available Dendritic cells (DC have the potential to control the outcome of autoimmunity by modulating the immune response. In this study, we tested the ability of Fasciola hepatica total extract (TE to induce tolerogenic properties in CpG-ODN (CpG maturated DC, to then evaluate the therapeutic potential of these cells to diminish the inflammatory response in collagen induced arthritis (CIA. DBA/1J mice were injected with TE plus CpG treated DC (T/C-DC pulsed with bovine collagen II (CII between two immunizations with CII and clinical scores CIA were determined. The levels of CII-specific IgG2 and IgG1 in sera, the histological analyses in the joints, the cytokine profile in the draining lymph node (DLN cells and in the joints, and the number, and functionality of CD4+CD25+Foxp3+ T cells (Treg were evaluated. Vaccination of mice with CII pulsed T/C-DC diminished the severity and incidence of CIA symptoms and the production of the inflammatory cytokine, while induced the production of anti-inflammatory cytokines. The therapeutic effect was mediated by Treg cells, since the adoptive transfer of CD4+CD25+ T cells, inhibited the inflammatory symptoms in CIA. The in vitro blockage of TGF-β in cultures of DLN cells plus CII pulsed T/C-DC inhibited the expansion of Treg cells. Vaccination with CII pulsed T/C-DC seems to be a very efficient approach to diminish exacerbated immune response in CIA, by inducing the development of Treg cells, and it is therefore an interesting candidate for a cell-based therapy for rheumatoid arthritis (RA.

Silencing of Foxp3 enhances the antitumor efficacy of GM-CSF genetically modified tumor cell vaccine against B16 melanoma

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Miguel A

2017-01-01

Full Text Available Antonio Miguel,1 Luis Sendra,1 Verónica Noé,2 Carles J Ciudad,2 Francisco Dasí,3,4 David Hervas,5 María José Herrero,1,6 Salvador F Aliño17 1Department of Pharmacology, Faculty of Medicine, University of Valencia, 2Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Barcelona, 3Research University Hospital of Valencia, INCLIVA Health Research Institute, 4Department of Physiology, Faculty of Medicine, University of Valencia Foundation, 5Biostatistics Unit, 6Pharmacogenetics Unit, Instituto de Investigación Sanitaria La Fe (IIS La Fe, 7Clinical Pharmacology Unit, ACM Hospital Universitario y Politécnico La Fe, Valencia, Spain Abstract: The antitumor response after therapeutic vaccination has a limited effect and seems to be related to the presence of T regulatory cells (Treg, which express the immunoregulatory molecules CTLA4 and Foxp3. The blockage of CTLA4 using antibodies has shown an effective antitumor response conducing to the approval of the human anti-CTLA4 antibody ipilimumab by the US Food and Drug Administration. On the other hand, Foxp3 is crucial for Treg development. For this reason, it is an attractive target for cancer treatment. This study aims to evaluate whether combining therapeutic vaccination with CTLA4 or Foxp3 gene silencing enhances the antitumor response. First, the “in vitro” cell entrance and gene silencing efficacy of two tools, 2'-O-methyl phosphorotioate-modified oligonucleotides (2'-OMe-PS-ASOs and polypurine reverse Hoogsteen hairpins (PPRHs, were evaluated in EL4 cells and cultured primary lymphocytes. Following B16 tumor transplant, C57BL6 mice were vaccinated with irradiated B16 tumor cells engineered to produce granulocyte-macrophage colony-stimulating factor (GM-CSF and were intraperitoneally treated with CTLA4 and Foxp3 2'-OMe-PS-ASO before and after vaccination. Tumor growth, mice survival, and CTLA4 and Foxp3 expression in blood cells were measured. The following

Missed, Not Missing: Phylogenomic Evidence for the Existence of Avian FoxP3.

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Michael P Denyer

Full Text Available The Forkhead box transcription factor FoxP3 is pivotal to the development and function of regulatory T cells (Tregs, which make a major contribution to peripheral tolerance. FoxP3 is believed to perform a regulatory role in all the vertebrate species in which it has been detected. The prevailing view is that FoxP3 is absent in birds and that avian Tregs rely on alternative developmental and suppressive pathways. Prompted by the automated annotation of foxp3 in the ground tit (Parus humilis genome, we have questioned this assumption. Our analysis of all available avian genomes has revealed that the foxp3 locus is missing, incomplete or of poor quality in the relevant genomic assemblies for nearly all avian species. Nevertheless, in two species, the peregrine falcon (Falco peregrinus and the saker falcon (F. cherrug, there is compelling evidence for the existence of exons showing synteny with foxp3 in the ground tit. A broader phylogenomic analysis has shown that FoxP3 sequences from these three species are similar to crocodilian sequences, the closest living relatives of birds. In both birds and crocodilians, we have also identified a highly proline-enriched region at the N terminus of FoxP3, a region previously identified only in mammals.

Effect of loop structure of bovine lactoferricin on apoptosis in Jurkat cells.

Science.gov (United States)

Zhang, Tie-nan; Yang, Wei; Liu, Ning

2010-06-01

Bovine lactoferricin (LfcinB) is a cationic peptide that selectively induces apoptosis in Jurkat cells. However less is known about the influence of this kind of apoptosis on the intra-cellular ceramide metabolism and the structure-function relationship between the loop structure of LfcinB and its action of inducing apoptosis in Jurkat cells. In the present study, the artificially synthesized LfcinB and LfcinB-derived peptide (Cys 19 residue in LfcinB was replaced by Ala) was added in Jurkat cells, the nucleolus shape was observed by fluorescent microscopy, the ceramide concentration in Jurkat cells was determined by reversed phase high performance liquid chromatography (RP-HPLC). The results of MTT assay showed that LfcinB inhibited proliferation of Jurkat cells, and the inhibition rate was approximately 18.90%. Moreover, the inhibition rate of LfcinB together with MAPP was upto approximately 59.89%. The RP-HPLC result showed that LfcinB improved the ceramide level in Jurkat cells. By using the DNA fragmentation assay and observing the nucleolus shape, the result displayed deficiency of the loop structure could cause LfcinB losing the biological activity of inducing apoptosis in Jurkat cells.

Effects of oral Lactobacillus administration on antioxidant activities and CD4+CD25+forkhead box P3 (FoxP3)+ T cells in NZB/W F1 mice.

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Tzang, Bor-Show; Liu, Chung-Hsien; Hsu, Kuo-Ching; Chen, Yi-Hsing; Huang, Chih-Yang; Hsu, Tsai-Ching

2017-09-01

Systemic lupus erythematosus (SLE) is an autoimmune disease that is characterised by a dysregulation of the immune system, which causes inflammation responses, excessive oxidative stress and a reduction in the number of cluster of differentiation (CD)4+CD25+forkhead box P3 (FoxP3)+ T cells. Supplementation with certain Lactobacillus strains has been suggested to be beneficial in the comprehensive treatment of SLE. However, little is known about the effect and mechanism of certain Lactobacillus strains on SLE. To investigate the effects of Lactobacillus on SLE, NZB/W F1 mice were orally gavaged with Lactobacillus paracasei GMNL-32 (GMNL-32), Lactobacillus reuteri GMNL-89 (GMNL-89) and L. reuteri GMNL-263 (GMNL-263). Supplementation with GMNL-32, GMNL-89 and GMNL-263 significantly increased antioxidant activity, reduced IL-6 and TNF-α levels and significantly decreased the toll-like receptors/myeloid differentiation primary response gene 88 signalling in NZB/W F1 mice. Notably, supplementation with GMNL-263, but not GMNL-32 and GMNL-89, in NZB/W F1 mice significantly increased the differentiation of CD4+CD25+FoxP3+ T cells. These findings reveal beneficial effects of GMNL-32, GMNL-89 and GMNL-263 on NZB/W F1 mice and suggest that these specific Lactobacillus strains can be used as part of a comprehensive treatment of SLE patients.

on Lymphoblastic Leukemia Jurkat Cells

African Journals Online (AJOL)

human tumor cell line (Hela) by using MTT assay. [13]. In the present study, we have observed the cytotoxic effect of ethanolic extract of C. arvensis against Jurkat cells, a human lymphoblastic leukemia cell line, by using Trypan blue, MTS assay and FACS analysis. It was shown from the trypan blue exclusion assay that ...

Increase of Circulating CD4(+)CD25(high)Foxp3(+) Regulatory T Cells in Patients With Metastatic Renal Cell Carcinoma During Treatment With Dendritic Cell Vaccination and Low-Dose Interleukin-2

DEFF Research Database (Denmark)

Berntsen, Annika; Brimnes, M.K.; Straten, P.T.

2010-01-01

Regulatory T cells (Treg) play an important role in the maintenance of immune tolerance and may be one of the obstacles of successful tumor immunotherapy. In this study, we analyzed the impact of administration of dendritic cell (DC) vaccination in combination with low-dose interleukin (IL)-2...... in patients with metastatic renal cell carcinoma on the frequency of CD4(+) CD25(high)Foxp3(+) Treg cells in peripheral blood. We found that the treatment increased the frequency of Treg cells more than 7-fold compared with pretreatment levels (P cells decreased when patients...... had been off IL-2 treatment for only 8 days, but remained higher than pretreatment levels. A functional assay showed that isolated Treg cells were capable of inhibiting proliferation of responder cells. Also, in vitro studies showed that coculture of mature DCs, autologous T cells and IL-2 leads...

A New Immunosuppressive Molecule Emodin Induces both CD4+FoxP3+ and CD8+CD122+ Regulatory T Cells and Suppresses Murine Allograft Rejection

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Feifei Qiu

2017-11-01

Full Text Available Due to vigorous alloimmunity, an allograft is usually rejected without any conventional immunosuppressive treatment. However, continuous global immunosuppression may cause severe side effects, including tumors and infections. Mounting evidence has shown that cyclosporine (CsA, a common immunosuppressant used in clinic, impedes allograft tolerance by dampening regulatory T cells (Tregs, although it inhibits allograft rejection at the same time. Therefore, it is necessary to seek an alternative immunosuppressive drug that spares Tregs with high efficiency in suppression but low toxicity. In this study, we investigated the capacity of emodin, an anthraquinone molecule originally extracted from certain natural plants, to prolong transplant survival in a mouse model and explored the cellular and molecular mechanisms underlying its action. We found that emodin significantly extended skin allograft survival and hindered CD3+ T cell infiltration in the allograft, accompanied by an increase in CD4+Foxp3+ and CD8+CD122+ Treg frequencies and numbers but a reduction in effector CD8+CD44highCD62Llow T cells in recipient mice. Emodin also inhibited effector CD8+ T cells proliferation in vivo. However, CD4+CD25+, but not CD8+CD122+, Tregs derived from emodin-treated recipients were more potent in suppression of allograft rejection than those isolated from control recipients, suggesting that emodin also enhances the suppressive function of CD4+CD25+ Tregs. Interestingly, depleting CD25+ Tregs largely reversed skin allograft survival prolonged by emodin while depleting CD122+ Tregs only partially abrogated the same allograft survival. Furthermore, we found that emodin hindered dendritic cell (DC maturation and reduced alloantibody production posttransplantation. Finally, we demonstrated that emodin inhibited in vitro proliferation of T cells and blocked their mTOR signaling as well. Therefore, emodin may be a novel mTOR inhibitor that suppresses alloimmunity by

Ionizing Radiation Induces Morphological Changes and Immunological Modulation of Jurkat Cells.

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Voos, Patrick; Fuck, Sebastian; Weipert, Fabian; Babel, Laura; Tandl, Dominique; Meckel, Tobias; Hehlgans, Stephanie; Fournier, Claudia; Moroni, Anna; Rödel, Franz; Thiel, Gerhard

2018-01-01

Impairment or stimulation of the immune system by ionizing radiation (IR) impacts on immune surveillance of tumor cells and non-malignant cells and can either foster therapy response or side effects/toxicities of radiation therapy. For a better understanding of the mechanisms by which IR modulates T-cell activation and alters functional properties of these immune cells, we exposed human immortalized Jurkat cells and peripheral blood lymphocytes (PBL) to X-ray doses between 0.1 and 5 Gy. This resulted in cellular responses, which are typically observed also in naïve T-lymphocytes in response of T-cell receptor immune stimulation or mitogens. These responses include oscillations of cytosolic Ca 2+ , an upregulation of CD25 surface expression, interleukin-2 and interferon-γ synthesis, elevated expression of Ca 2+ sensitive K + channels and an increase in cell diameter. The latter was sensitive to inhibition by the immunosuppressant cyclosporine A, Ca 2+ buffer BAPTA-AM, and the CDK1-inhibitor RO3306, indicating the involvement of Ca 2+ -dependent immune activation and radiation-induced cell cycle arrest. Furthermore, on a functional level, Jurkat and PBL cell adhesion to endothelial cells was increased upon radiation exposure and was highly dependent on an upregulation of integrin beta-1 expression and clustering. In conclusion, we here report that IR impacts on immune activation and functional properties of T-lymphocytes that may have implications in both toxic effects and treatment response to combined radiation and immune therapy in cancer patients.

FOXP3+ T Cells Recruited to Sites of Sterile Skeletal Muscle Injury Regulate the Fate of Satellite Cells and Guide Effective Tissue Regeneration

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Castiglioni, Alessandra; Basso, Veronica; Vezzoli, Michela; Monno, Antonella; Almada, Albert E.; Mondino, Anna; Wagers, Amy J.; Manfredi, Angelo A.; Rovere-Querini, Patrizia

2015-01-01

Muscle injury induces a classical inflammatory response in which cells of the innate immune system rapidly invade the tissue. Macrophages are prominently involved in this response and required for proper healing, as they are known to be important for clearing cellular debris and supporting satellite cell differentiation. Here, we sought to assess the role of the adaptive immune system in muscle regeneration after acute damage. We show that T lymphocytes are transiently recruited into the muscle after damage and appear to exert a pro-myogenic effect on muscle repair. We observed a decrease in the cross-sectional area of regenerating myofibers after injury in Rag2-/- γ-chain-/- mice, as compared to WT controls, suggesting that T cell recruitment promotes muscle regeneration. Skeletal muscle infiltrating T lymphocytes were enriched in CD4+CD25+FOXP3+ cells. Direct exposure of muscle satellite cells to in vitro induced Treg cells effectively enhanced their expansion, and concurrently inhibited their myogenic differentiation. In vivo, the recruitment of Tregs to acutely injured muscle was limited to the time period of satellite expansion, with possibly important implications for situations in which inflammatory conditions persist, such as muscular dystrophies and inflammatory myopathies. We conclude that the adaptive immune system, in particular T regulatory cells, is critically involved in effective skeletal muscle regeneration. Thus, in addition to their well-established role as regulators of the immune/inflammatory response, T regulatory cells also regulate the activity of skeletal muscle precursor cells, and are instrumental for the proper regeneration of this tissue. PMID:26039259

T Helper 17 Cells Interplay with CD4+CD25highFoxp3+ Tregs in Regulation of Inflammations and Autoimmune Diseases

Science.gov (United States)

Mai, Jietang; Wang, Hong; Yang#, Xiao-Feng

2010-01-01

Interleukin-17 (IL-17)-secreting T helper 17 cells (Th17) are a recently identified CD4+ T helper subset that has been implicated in various inflammatory and autoimmune diseases. Th17, along with CD4+CD25high Foxp3+ regulatory T cells (Tregs) and other newly emergent T helper subsets, Th9 and Tfh, have expanded the Th1-Th2 paradigm. Although this newly proposed six-subset paradigm significantly improved our understanding on the differentiation of CD4+ T helper cell subsets and the regulation of T helper cells in inflammation and autoimmunity, many questions remain to be answered. In this overview, we will briefly review the following issues: a) Old Th1-Th2 paradigm versus new multi-subset paradigm; b) Structural features of IL-17 family cytokines; c) Th17 cells; d) Effects of IL-17 on various cell types and tissues; e) IL-17 receptor and signaling pathways; f) Th17-mediated inflammations; and g) Protective mechanisms of IL-17 in infections. Lastly, we will look into the interaction of Th17 and Treg in autoimmune diseases and inflammation: Th17 cells interplay with Tregs. Regulation of autoimmunity and inflammation lies in the interplays of the different T helper subsets, therefore, better understanding of these subsets’ interactions with one another would greatly improve our approaches in developing therapy to combat inflammatory and autoimmune diseases. PMID:20515737

FOXP3 Transcription Factor: A Candidate Marker for Susceptibility and Prognosis in Triple Negative Breast Cancer

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Leandra Fiori Lopes

2014-01-01

Full Text Available Triple negative breast cancer (TNBC is a relevant subgroup of neoplasia which presents negative phenotype of estrogen and progesterone receptors and has no overexpression of the human epidermal growth factor 2 (HER2. FOXP3 (forkhead transcription factor 3 is a marker of regulatory T cells (Tregs, whose expression may be increased in tumor cells. This study aimed to investigate a polymorphism (rs3761548 and the protein expression of FOXP3 for a possible involvement in TNBC susceptibility and prognosis. Genetic polymorphism was evaluated in 50 patients and in 115 controls by allele-specific PCR (polymerase chain reaction. Protein expression was evaluated in 38 patients by immunohistochemistry. It was observed a positive association for homozygous AA (OR = 3.78; 95% CI = 1.02–14.06 in relation to TNBC susceptibility. Most of the patients (83% showed a strong staining for FOXP3 protein in the tumor cells. In relation to FOXP3-positive infiltrate, 47% and 58% of patients had a moderate or intense intratumoral and peritumoral mononuclear infiltrate cells, respectively. Tumor size was positively correlated to intratumoral FOXP3-positive infiltrate (P=0.026. In conclusion, since FOXP3 was positively associated with TNBC susceptibility and prognosis, it seems to be a promising candidate for further investigation in larger TNBC samples.

STAT3-mediated constitutive expression of SOCS-3 in cutaneous T-cell lymphoma

DEFF Research Database (Denmark)

Brender, C; Nielsen, M; Kaltoft, K

2001-01-01

) obtained from affected skin from a patient with mycosis fungoides (MF) and from peripheral blood from a patient with Sezary syndrome (SS). In contrast, constitutive SOCS-3 expression is not found in the leukemic Jurkat T-cell line, the MOLT-4 acute lymphoblastic leukemia cell line, and the monocytic......, it has been hypothesized that an aberrant SOCS expression plays a role in neoplastic transformation. This study reports on a constitutive SOCS-3 expression in cutaneous T-cell lymphoma (CTCL) cell lines. SOCS-3 protein is constitutively expressed in tumor cell lines (but not in nonmalignant T cells...... leukemic cell line U937. Expression of SOCS-3 coincides with a constitutive activation of STAT3 in CTCL tumor cells, and stable transfection of CTCL tumor cells with a dominant negative STAT3 strongly inhibits SOCS-3 expression, whereas transfection with wild-type STAT3 does not. Moreover, the reduced SOCS...

Perspectives on Regulatory T Cell Therapies

OpenAIRE

Probst-Kepper, Michael; Kröger, Andrea; Garritsen, Henk S.P.; Buer, Jan

2009-01-01

Adoptive transfer in animal models clearly indicate an essential role of CD4+ CD25+ FOXP3+ regulatory T (Treg) cells in prevention and treatment of autoimmune and graft-versus-host disease. Thus, Treg cell therapies and development of drugs that specifically enhance Treg cell function and development represent promising tools to establish dominant tolerance. So far, lack of specific markers to differentiate human Treg cells from activated CD4+ CD25+ effector T cells, which also express FOXP3 ...

IL-12 and IL-23 modulate plasticity of FoxP3+ regulatory T cells in human Leprosy.

Science.gov (United States)

Tarique, Mohd; Saini, Chaman; Naqvi, Raza Ali; Khanna, Neena; Sharma, Alpana; Rao, D N

2017-03-01

Leprosy is a bacterial disease caused by M. leprae. Its clinical spectrum reflects the host's immune response to the M. leprae and provide an ideal model to investigate the host pathogen interaction and immunological dysregulation. Tregs are high in leprosy patients and responsible for immune suppression of the host by producing IL-10 and TGF-β cytokines. In leprosy, plasticity of Tregs remain unstudied. This is the first study describing the conversion of Tregs into Th1-like and Th17-like cells using in vitro cytokine therapy in leprosy patients. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA), rIL-12 and rIL-23 for 48h. Expression of FoxP3 in CD4 + CD25 + Tregs, intracellular cytokines IFN-γ, TGF-β, IL-10 and IL-17 in Tregs cells were evaluated by flow cytometry (FACS) after stimulation. rIL-12 treatment increases the levels of pStat4 in Tregs and IFN-γ production. In the presence of rIL-23, pStat3 + and IL-17A + cells increase. rIL-12 and r-IL-23 treatment downregulated the FoxP3 expression, IL-10 and TGF-β production by Tregs and enhances the expression of co-stimulatory molecules (CD80, CD86). In conclusion rIL-12 converts Tregs into IFN-γ producing cells through STAT-4 signaling while rIL-23 converts Tregs into IL-17 producing cells through STAT-3 signaling in leprosy patients. This study may helpful to provide a new avenue to overcome the immunosuprression in leprosy patients using in vitro cytokine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human T-cell line (Jurkat cell) encapsulation by nano-organized polyelectrolytes and their response assessment in vitro and in vivo

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Pandey, Siddharth [Institute of Nuclear Medicine and Allied Sciences (INMAS), Stem Cell and Gene Therapy Research Group (India); Afrin, Fahrat [Jamia Hamdard, Department of Biotechnology (India); Tripathi, R. P.; Gangenahalli, Gurudutta, E-mail: gugdutta@rediffmail.com [Institute of Nuclear Medicine and Allied Sciences (INMAS), Stem Cell and Gene Therapy Research Group (India)

2013-07-15

Single living Jurkat cells have been encapsulated through polyelectrolytes nanoparticles poly(allyl amine hydrochloride) size 15.6 nm and poly(styrene-co-sulfonic acid sodium salt) size 30.2 nm, through layer by layer coating of oppositely charged plasma membrane. Confocal microscopy and scanning electron microscopy results showed complete shielding of Jurkat cells, and no changes in cell surface morphology of encapsulated cells were observed. Cell viability was not affected after encapsulation and no toxicity was found. In vivo studies demonstrated no significant changes in hematological and biochemical parameters of blood serum at day 1 and 7 in mice. Histopathological analyses of liver and spleen tissues showed nontoxic nature of prepared formulations.

Differential effects of IL-2 and IL-21 on expansion of the CD4+ CD25+ Foxp3+ T regulatory cells with redundant roles in natural killer cell mediated antibody dependent cellular cytotoxicity in chronic lymphocytic leukemia.

Science.gov (United States)

Gowda, Aruna; Ramanunni, Asha; Cheney, Carolyn; Rozewski, Darlene; Kindsvogel, Wayne; Lehman, Amy; Jarjoura, David; Caligiuri, Michael; Byrd, John C; Muthusamy, Natarajan

2010-01-01

CD4(+) CD25(+) regulatory T cells are expanded in solid and hematological malignancies including chronic lymphocytic leukemia (CLL). Several cytokines and co-stimulatory molecules are required for generation, survival and maintenance of their suppressive effect. We and others have shown direct cytotoxic effect of the novel common gamma chain cytokine interleukin (IL)-21 on primary B cells from CLL patients. Since members of this family of cytokines are known to exhibit their effects on diverse immune cells, we have examined the effects of IL-21 on CLL patient derived regulatory T cell (Treg) induction, expansion and the inhibitory effect on natural killer cells in vitro. We demonstrate here the expression of IL-21 receptor in CD4(+)CD25(High) regulatory cells from CLL patients. In contrast to IL-2, the IL-21 cytokine failed to mediate expansion of regulatory T cells or induced expression of Foxp3 in CD4(+)CD25(Intermediate) or CD4(+)CD25(Dim/-) T cells in whole blood derived from CLL patients. Interestingly, in contrast to their differential effects on expansion of the CD4(+)CD25(+)Foxp3(+)T cells, IL-2 and IL-21 exhibited a redundant role in Treg mediated suppression of NK cell mediated antibody dependent cytotoxicity function. Given the infusion related toxicities and pro-survival effect of IL-2 in CLL, these studies provide a rationale to explore IL-21 as an alternate gamma chain cytokine in CLL therapy.

Isolation of highly suppressive CD25+FoxP3+ T regulatory cells from G-CSF-mobilized donors with retention of cytotoxic anti-viral CTLs: application for multi-functional immunotherapy post stem cell transplantation.

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Edward R Samuel

Full Text Available Previous studies have demonstrated the effective control of cytomegalovirus (CMV infections post haematopoietic stem cell transplant through the adoptive transfer of donor derived CMV-specific T cells (CMV-T. Strategies for manufacturing CMV immunotherapies has involved a second leukapheresis or blood draw from the donor, which in the unrelated donor setting is not always possible. We have investigated the feasibility of using an aliquot of the original G-CSF-mobilized graft as a starting material for manufacture of CMV-T and examined the activation marker CD25 as a targeted approach for identification and isolation following CMVpp65 peptide stimulation. CD25+ cells isolated from G-CSF-mobilized apheresis revealed a significant increase in the proportion of FoxP3 expression when compared with conventional non-mobilized CD25+ cells and showed a superior suppressive capacity in a T cell proliferation assay, demonstrating the emergence of a population of Tregs not present in non-mobilized apheresis collections. The expansion of CD25+ CMV-T in short-term culture resulted in a mixed population of CD4+ and CD8+ T cells with CMV-specificity that secreted cytotoxic effector molecules and lysed CMVpp65 peptide-loaded phytohaemagglutinin-stimulated blasts. Furthermore CD25 expanded cells retained their suppressive capacity but did not maintain FoxP3 expression or secrete IL-10. In summary our data indicates that CD25 enrichment post CMV stimulation in G-CSF-mobilized PBMCs results in the simultaneous generation of both a functional population of anti-viral T cells and Tregs thus illustrating a potential single therapeutic strategy for the treatment of both GvHD and CMV reactivation following allogeneic haematopoietic stem cell transplantation. The use of G-CSF-mobilized cells as a starting material for cell therapy manufacture represents a feasible approach to alleviating the many problems incurred with successive donations and procurement of cells from

Ionizing Radiation Induces Morphological Changes and Immunological Modulation of Jurkat Cells

Directory of Open Access Journals (Sweden)

Patrick Voos

2018-04-01

Full Text Available Impairment or stimulation of the immune system by ionizing radiation (IR impacts on immune surveillance of tumor cells and non-malignant cells and can either foster therapy response or side effects/toxicities of radiation therapy. For a better understanding of the mechanisms by which IR modulates T-cell activation and alters functional properties of these immune cells, we exposed human immortalized Jurkat cells and peripheral blood lymphocytes (PBL to X-ray doses between 0.1 and 5 Gy. This resulted in cellular responses, which are typically observed also in naïve T-lymphocytes in response of T-cell receptor immune stimulation or mitogens. These responses include oscillations of cytosolic Ca2+, an upregulation of CD25 surface expression, interleukin-2 and interferon-γ synthesis, elevated expression of Ca2+ sensitive K+ channels and an increase in cell diameter. The latter was sensitive to inhibition by the immunosuppressant cyclosporine A, Ca2+ buffer BAPTA-AM, and the CDK1-inhibitor RO3306, indicating the involvement of Ca2+-dependent immune activation and radiation-induced cell cycle arrest. Furthermore, on a functional level, Jurkat and PBL cell adhesion to endothelial cells was increased upon radiation exposure and was highly dependent on an upregulation of integrin beta-1 expression and clustering. In conclusion, we here report that IR impacts on immune activation and functional properties of T-lymphocytes that may have implications in both toxic effects and treatment response to combined radiation and immune therapy in cancer patients.

Illicium verum Extract and Trans-Anethole Attenuate Ovalbumin-Induced Airway Inflammation via Enhancement of Foxp3+ Regulatory T Cells and Inhibition of Th2 Cytokines in Mice

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Yoon-Young Sung

2017-01-01

Full Text Available Illicium verum is used in traditional medicine to treat inflammation. The study investigates the effects of IVE and its component, trans-anethole (AET, on airway inflammation in ovalbumin- (OVA- induced asthmatic mice. Asthma was induced in BALB/c mice by systemic sensitization to OVA, followed by intratracheal, intraperitoneal, and aerosol allergen challenges. IVE and AET were orally administered for four weeks. We investigated the effects of treatment on airway hyperresponsiveness, IgE production, pulmonary eosinophilic infiltration, immune cell phenotypes, Th2 cytokine production in bronchoalveolar lavage, Th1/Th2 cytokine production in splenocytes, forkhead box protein 3 (Foxp3 expression, and lung histology. IVE and AET ameliorated OVA-driven airway hyperresponsiveness (p<0.01, pulmonary eosinophilic infiltration (p<0.05, mucus hypersecretion (p<0.01, and IL-4, IL-5, IL-13, and CCR3 production (p<0.05, as well as IgE levels (p<0.01. IVE and AET increased Foxp3 expression in lungs (p<0.05. IVE and AET reduced IL-4 and increased IFN-γ production in the supernatant of splenocyte cultures (p<0.05. Histological studies showed that IVE and AET inhibited eosinophilia and lymphocyte infiltration in lungs (p<0.01. These results indicate that IVE and AET exert antiasthmatic effects through upregulation of Foxp3+ regulatory T cells and inhibition of Th2 cytokines, suggesting that IVE may be a potential therapeutic agent for allergic lung inflammation.

Benzo[a]pyrene affects Jurkat T cells in the activated state via the antioxidant response element dependent Nrf2 pathway leading to decreased IL-2 secretion and redirecting glutamine metabolism

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Murugaiyan, Jayaseelan; Rockstroh, Maxie; Wagner, Juliane [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Baumann, Sven [Department of Metabolomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Schorsch, Katrin [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Trump, Saskia; Lehmann, Irina [Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Bergen, Martin von [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Aalborg (Denmark); Tomm, Janina M., E-mail: Janina.tomm@ufz.de [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany)

2013-06-15

There is a clear evidence that environmental pollutants, such as benzo[a]pyrene (B[a]P), can have detrimental effects on the immune system, whereas the underlying mechanisms still remain elusive. Jurkat T cells share many properties with native T lymphocytes and therefore are an appropriate model to analyze the effects of environmental pollutants on T cells and their activation. Since environmental compounds frequently occur at low, not acute toxic concentrations, we analyzed the effects of two subtoxic concentrations, 50 nM and 5 μM, on non- and activated cells. B[a]P interferes directly with the stimulation process as proven by an altered IL-2 secretion. Furthermore, B[a]P exposure results in significant proteomic changes as shown by DIGE analysis. Pathway analysis revealed an involvement of the AhR independent Nrf2 pathway in the altered processes observed in unstimulated and stimulated cells. A participation of the Nrf2 pathway in the change of IL-2 secretion was confirmed by exposing cells to the Nrf2 activator tBHQ. tBHQ and 5 μM B[a]P caused similar alterations of IL-2 secretion and glutamine/glutamate metabolism. Moreover, the proteome changes in unstimulated cells point towards a modified regulation of the cytoskeleton and cellular stress response, which was proven by western blotting. Additionally, there is a strong evidence for alterations in metabolic pathways caused by B[a]P exposure in stimulated cells. Especially the glutamine/glutamate metabolism was indicated by proteome pathway analysis and validated by metabolite measurements. The detrimental effects were slightly enhanced in stimulated cells, suggesting that stimulated cells are more vulnerable to the environmental pollutant model compound B[a]P. - Highlights: • B[a]P affects the proteome of Jurkat T cells also at low concentrations. • Exposure to B[a]P (50 nM, 5 μM) did not change Jurkat T cell viability. • Both B[a]P concentrations altered the IL-2 secretion of stimulated cells. �

[Heat shock protein 90--modulator of TNFalpha-induced apoptosis of Jurkat tumor cells].

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Kaĭgorodova, E V; Riazantseva, N V; Novitskiĭ, V V; Moroshkina, A N; Belkina, M V; Iakushina, V D

2011-01-01

rTNFalpha-induced programmed death of Jurkat tumor cells cultured with 17-AAG, a selective inhibitor of heat shock protein (Hsp90), was studied by fluorescent microscopy with the use of FITC-labeled annexin V and propidium iodide. Caspase-3 and -8 activities were determined by spectrophotometry using a caspase- 3 and -8 colorimetric assay kit. It was shown that inhibition of Hsp90 leads to activation of Jurkat cell apoptosis while Hsp90 itself suppresses this process. 17-AAG enhances rTNFa-induced apoptosis of tumor cells.

FOXP3 expression in papillary thyroid carcinoma with and without Hashimoto's thyroiditis

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Murilo Pedreira Neves Junior

2013-08-01

Full Text Available INTRODUCTION: The forkhead box P3 (FOXP3 plays a role in cell development and control. In the presence of abnormal FOXP3 expression, tumor cells may evade the immunosurveillance of lymphoid cells, the first step for the maintenance of cancer cells in the thyroid tissue. OBJECTIVE: To identify the presence of FOXP3 in papillary thyroid carcinoma (PTC with and without Hashimoto's Thyroiditis (HT. METHODS: We conducted a series study of cases collected from 2000 to 2008, when 1,438 thyroidectomies were performed. We selected those diagnosed with PTC, comprising 466 cases. 30 patients were randomly selected for purposes of immunohistochemistry with antibodies against FOXP3. RESULT: FOXP3 revealed high positivity for PTC and positive immunostaining was present in 21 (72.4% from all analyzed cases. There was no difference regarding coexistent HT or not. DISCUSSION AND CONCLUSION: In the present study, it was evidenced that the focal or diffuse FOXP3 expression was commonly observed in neoplastic cells from PTC, hence indicating that the assessment of this molecule expression in suspected cases of thyroid cancer may contribute to its diagnosis.

The ThPOK transcription factor differentially affects the development and function of self-specific CD8(+) T cells and regulatory CD4(+) T cells.

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Twu, Yuh-Ching; Teh, Hung-Sia

2014-03-01

The zinc finger transcription factor ThPOK plays a crucial role in CD4 T-cell development and CD4/CD8 lineage decision. In ThPOK-deficient mice, developing T cells expressing MHC class II-restricted T-cell receptors are redirected into the CD8 T-cell lineage. In this study, we investigated whether the ThPOK transgene affected the development and function of two additional types of T cells, namely self-specific CD8 T cells and CD4(+) FoxP3(+) T regulatory cells. Self-specific CD8 T cells are characterized by high expression of CD44, CD122, Ly6C, 1B11 and proliferation in response to either IL-2 or IL-15. The ThPOK transgene converted these self-specific CD8 T cells into CD4 T cells. The converted CD4(+) T cells are no longer self-reactive, lose the characteristics of self-specific CD8 T cells, acquire the properties of conventional CD4 T cells and survive poorly in peripheral lymphoid organs. By contrast, the ThPOK transgene promoted the development of CD4(+) FoxP3(+) regulatory T cells resulting in an increased recovery of CD4(+) FoxP3(+) regulatory T cells that expressed higher transforming growth factor-β-dependent suppressor activity. These studies indicate that the ThPOK transcription factor differentially affects the development and function of self-specific CD8 T cells and CD4(+) FoxP3(+) regulatory T cells. © 2013 John Wiley & Sons Ltd.

Interplay of T Helper 17 Cells with CD4+CD25high FOXP3+ Tregs in Regulation of Allergic Asthma in Pediatric Patients

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Amit Agarwal

2014-01-01

Full Text Available Background. There is evidence that Tregs are important to prevent allergic diseases like asthma but limited literature exists on role of TH17 cells in allergic diseases. Methods. Fifty children with asthma and respiratory allergy (study group and twenty healthy children (control group were recruited in this study. Total IgE levels and pulmonary function tests were assessed. The expression of Tregs and cytokines was determined by flow cytometry. Results. The average level of total IgE in study group (316.8 ± 189.8 IU/mL was significantly higher than controls (50 ± 17.5 IU/mL, P<0.0001. The frequency of TH17 cells and culture supernatant level of IL-17 in study group (12.09 ± 8.67 pg/mL was significantly higher than control group (2.01 ± 1.27 pg/mL, P<0.001. Alternatively, the frequency of FOXP3 level was significantly lower in study group [(49.00 ± 13.47%] than in control group [(95.91 ± 2.63%] and CD4+CD25+FOXP3+ to CD4+CD25+ ratio was also significantly decreased in study group [(6.33 ± 2.18%] compared to control group [(38.61 ± 11.04%]. The total serum IgE level is negatively correlated with FOXP3 level (r=-0.5273, P<0.0001. The FOXP3 expression is negatively correlated with the IL-17 levels (r=-0.5631, P<0.0001 and IL-4 levels (r=-0.2836, P=0.0460. Conclusions. Imbalance in TH17/Tregs, elevated IL-17, and IL-4 response and downregulation of FOXP3 were associated with allergic asthma.

Antitumor effect of triptolide in T-cell lymphoblastic lymphoma by inhibiting cell viability, invasion, and epithelial–mesenchymal transition via regulating the PI3K/AKT/mTOR pathway

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Huang Y

2018-02-01

Full Text Available Yan Huang, Sun Wu, Yuan Zhang, Lihua Wang, Yan Guo Department of Hematology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, People’s Republic of China Introduction: T-cell lymphoblastic lymphoma (T-LBL is a widely disseminated disease worldwide. Triptolide (TPL is purified from Chinese herb and displays anti-inflammatory, anti-fertility, anti-tumor and immunosuppressive effects. Materials and methods: Here, in vitro and in vivo experiments were conducted to investigate the anti-tumor effect of TPL treatment in T-LBL and the potential mechanism in T-LBL progression. Results: TPL inhibited cell proliferation of T-LBL cells (Jurkat cells and Molt-3 cells in a dose-dependent manner. Flow cytometry analysis showed that cell apoptosis rate was increased by TPL treatment. TPL also up-regulated the expression of Caspase-3, Bax and down-regulated the expression of Bcl-2, indicating that TPL promoted apoptosis in Jurkat cells. Moreover, TPL inhibited invasion ability of Jurkat cells and down-regulated the expression of MMP-3 and MMP-9 in a dose-dependent manner. The expression of Snail, Slug, Twist and Integrin αVβ6 was decreased and the expression of E-cadherin was increased by TPL treatment, indicating that TPL inhibited EMT of Jurkat cells. Apart from that, TPL treatment attenuated the phoslevels of PI3K, Akt and mTOR and suppressed AKT activation compared with control group, suggesting that TPL inhibited PI3K/Akt/mTOR signal pathway in T-LBL. In vivo experiments showed that TPL inhibited tumor growth of T-LBL and promoted apoptosis of tumor cells. The expression of PCNA, Bcl-2, Snail, p-PI3K, p-Akt and mTOR was suppressed by TPL in a dose-dependent manner, suggesting that TPL suppressed tumor growth and promoted apoptosis of tumor cells by inhibiting PI3K/Akt/mTOR signal pathway in T-LBL. Conclusion: In conclusion, TPL exerted anti-tumor effect in T-LBL by inhibiting cell viability, invasion and EMT via regulating the PI3K

RelB+ Steady-State Migratory Dendritic Cells Control the Peripheral Pool of the Natural Foxp3+ Regulatory T Cells

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Anja Döhler

2017-06-01

Full Text Available Thymus-derived natural Foxp3+ CD4+ regulatory T cells (nTregs play a key role in maintaining immune tolerance and preventing autoimmune disease. Several studies indicate that dendritic cells (DCs are critically involved in the maintenance and proliferation of nTregs. However, the mechanisms how DCs manage to keep the peripheral pool at constant levels remain poorly understood. Here, we describe that the NF-κB/Rel family transcription factor RelB controls the frequencies of steady-state migratory DCs (ssmDCs in peripheral lymph nodes and their numbers control peripheral nTreg homeostasis. DC-specific RelB depletion was investigated in CD11c-Cre × RelBfl/fl mice (RelBDCko, which showed normal frequencies of resident DCs in lymph nodes and spleen while the subsets of CD103− Langerin− dermal DCs (dDCs and Langerhans cells but not CD103+ Langerin+ dDC of the ssmDCs in skin-draining lymph nodes were increased. Enhanced frequencies and proliferation rates were also observed for nTregs and a small population of CD4+ CD44high CD25low memory-like T cells (Tml. Interestingly, only the Tml but not DCs showed an increase in IL-2-producing capacity in lymph nodes of RelBDCko mice. Blocking of IL-2 in vivo reduced the frequency of nTregs but increased the Tml frequencies, followed by a recovery of nTregs. Taken together, by employing RelBDCko mice with increased frequencies of ssmDCs our data indicate a critical role for specific ssmDC subsets for the peripheral nTreg and IL-2+ Tml frequencies during homeostasis.

Foxp3 (-/ATT polymorphism contributes to the susceptibility of preeclampsia.

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Ximing Chen

Full Text Available OBJECTIVE: To evaluate the potential influence of Foxp3 polymorphism on preeclampsia (PE susceptibility, we conducted a case-control study in Han Chinese women. METHODS: Foxp3 genotyping was determined by polymerase chain reaction with sequence-specific primers (PCR-SSP in 156 PE patients and 252 age-frequency matched controls. Immunohistochemical staining was used to detect the expression of Foxp3 specific transcription factor in 30 PE and 30 normal pregnant women. RESULTS: The positive rate of Foxp3 expression in PE (26.67% was significant difference from that in normal control (63.33%, P<0.05. The frequency of Foxp3-6054 TT genotype was significantly lower in PE patient than that in control. No significant difference was found in Foxp3-3279 genotypes between PE and control, as well as for the variant allele. The frequency of Foxp3-6054A/-3279C haplotype in PE was significantly higher than that in control (P<0.01, while the frequency of Foxp3 6054T/-3279C haplotype was significantly lower in PE patient than that in control (P<0.01. CONCLUSION: Our findings suggest that the immune suppression function in PE patients is weakened, which may result in the occurrence of PE. Foxp3 polymorphism (rs5902434 may be a potential contributor for the development of PE in Han Chinese women.

The Ratio of Regulatory (FOXP3+) to Total (CD3+) T Cells Determined by Epigenetic Cell Counting and Cardiovascular Disease Risk: A Prospective Case-cohort Study in Non-diabetics.

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Barth, Sebastian Dietmar; Kaaks, Rudolf; Johnson, Theron; Katzke, Verena; Gellhaus, Katharina; Schulze, Janika Josephin; Olek, Sven; Kühn, Tilman

2016-09-01

Experimental and clinical evidence indicate that inflammatory processes in atherogenesis and the development of cardiovascular complications are promoted by a loss of regulatory T cell (Treg)-mediated immunological tolerance to plaque antigens. Yet, the association between alterations of systemic Treg frequency and cardiovascular disease incidence remains uncertain. A nested case-cohort study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg, comprising a random subcohort (n=778) and primary cases of myocardial infarction (MI, n=276) and ischemic stroke (n=151). Pre-diagnostic FOXP3+ Treg and total CD3+ T-lymphocyte (tTL) frequencies in blood were measured by epigenetic-based, quantitative real-time PCR-assisted cell counting. Multivariate, Prentice-weighted Cox regression analyses revealed that lower Treg/tTL ratios were not associated with the risk of either MI (lowest vs. highest sex-specific quartile; hazard ratio: 0.72, 95% confidence interval: 0.46 to 1.13; P trend =0.51) or stroke (HR: 0.90, 95% CI: 0.51 to 1.60; P trend =0.78). There were no correlations of Treg/tTL ratios with C-reactive protein, HbA1c, and various lipid parameters. Among middle-aged adults from the general population, imbalances in the relative frequency of Tregs within the total T cell compartment do not confer an increased risk of MI or stroke. Copyright © 2016 Forschungsgesellschaft für Arbeitsphysiologie und Arbeitschutz e.V. Published by Elsevier B.V. All rights reserved.

HTLV-1 bZIP factor induces T-cell lymphoma and systemic inflammation in vivo.

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Yorifumi Satou

2011-02-01

Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 is the causal agent of a neoplastic disease of CD4+ T cells, adult T-cell leukemia (ATL, and inflammatory diseases including HTLV-1 associated myelopathy/tropical spastic paraparesis, dermatitis, and inflammatory lung diseases. ATL cells, which constitutively express CD25, resemble CD25+CD4+ regulatory T cells (T(reg. Approximately 60% of ATL cases indeed harbor leukemic cells that express FoxP3, a key transcription factor for T(reg cells. HTLV-1 encodes an antisense transcript, HTLV-1 bZIP factor (HBZ, which is expressed in all ATL cases. In this study, we show that transgenic expression of HBZ in CD4+ T cells induced T-cell lymphomas and systemic inflammation in mice, resembling diseases observed in HTLV-1 infected individuals. In HBZ-transgenic mice, CD4+Foxp3+ T(reg cells and effector/memory CD4+ T cells increased in vivo. As a mechanism of increased T(reg cells, HBZ expression directly induced Foxp3 gene transcription in T cells. The increased CD4+Foxp3+ T(reg cells in HBZ transgenic mice were functionally impaired while their proliferation was enhanced. HBZ could physically interact with Foxp3 and NFAT, thereby impairing the suppressive function of T(reg cells. Thus, the expression of HBZ in CD4+ T cells is a key mechanism of HTLV-1-induced neoplastic and inflammatory diseases.

FOXP1 forkhead transcription factor is associated with the pathogenesis of endometrial cancer

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Makito Mizunuma

2016-05-01

Full Text Available Endometrial cancers are mostly estrogen-dependent. FOXP1 is a P subfamily of forkhead box (FOX, and known as an estrogen-responsive transcription factor. The aims of this study were to examine histological location of FOXP1 in normal and malignant endometrium, and to investigate a possible association between FOXP1 and other factors considered to be involved in pathogenesis of endometrial cancer. The levels of FOXP1, estrogen receptor (ERα, and ERβ expression were examined immunohistochemically in normal and malignant endometrium obtained from 75 women (8 normal, 8 atypical endometrial hyperplasia, and 59 endometrial cancers from grade 1 to 3. The effects of estrogen on ERα, FOXP1, KRAS, and PTEN expression were analyzed in telomerase-immortalized human endometrial stromal cells (T HESCs by Western blotting. Western blotting was also used to examine the effect of FOXP1 plasmid DNA or siRNA transfection on KRAS and PTEN expression in Ishikawa cells (well differentiated endometrioid adenocarcinoma, HEC-50B cells (poorly differentiated endometrioid adenocarcinoma, and T HESCs, respectively. FOXP1 was expressed in normal and malignant endometrium, but the rate of expression was different depending upon menstrual cycle and pathological grade of malignancy. FOXP1 expression in nucleus and cytoplasm of grade 3 endometrioid cancers was significantly lower than that of grade 1 and 2 ones. Estradiol increased levels of FOXP1 and KRAS expression in a dose- and time-dependent manner in T HESCs cells, and FOXP1 transfection or knockdown led to increase or decrease of KRAS expression but not PTEN. KRAS expression level was significantly related to FOXP1 and ERα levels in cancer tissues. Estradiol did not affect KRAS expression in T HESCs cells transfected with FOXP1 siRNA. These results suggest that FOXP1 is involved in estrogen dependent endometrial cancers through KRAS pathway.

Runx1 and Runx3 are involved in the generation and function of highly suppressive IL-17-producing T regulatory cells.

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Lequn Li

Full Text Available CD4(+Foxp3(+ T regulatory cells (Tregs display phenotypic and functional plasticity that is regulated by cytokines and other immune cells. Previously, we determined that during co-culture with CD4(+CD25(- T cells and antigen presenting cells, Tregs produced IL-17. Here, we investigated the mechanisms underlying the differentiation of IL-17-producing Treg (Tr17 cells and their molecular and functional properties. We determined that during stimulation via TCR/CD3 and CD28, the combination of IL-1β and IL-2 was necessary and sufficient for the generation of Tr17 cells. Tr17 cells expressed Runx1 transcription factor, which was required for sustained expression of Foxp3 and RORγt and for production of IL-17. Surprisingly, Tr17 cells also expressed Runx3, which regulated transcription of perforin and granzyme B thereby mediating cytotoxic activity. Our studies indicate that Tr17 cells concomitantly express Foxp3, RORγt, Runx1 and Runx3 and are capable of producing IL-17 while mediating potent suppressive and cytotoxic function.

Comparative immune phenotypic analysis of cutaneous Squamous Cell Carcinoma and Intraepidermal Carcinoma in immune-competent individuals: proportional representation of CD8+ T-cells but not FoxP3+ Regulatory T-cells is associated with disease stage.

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Andrew Freeman

Full Text Available Squamous Cell Carcinoma (SCC is a type of non-melanoma skin cancer prevalent in immune-suppressed transplant recipients and older individuals with a history of chronic sun-exposure. SCC itself is believed to be a late-stage manifestation that can develop from premalignant lesions including Intraepidermal Carcinoma (IEC. Notably, while SCC regression is rare, IEC typically regresses in response to immune modifying topical treatments, however the underlying immunological reasons for these differential responses remain unclear. This study aimed to define whether IEC and SCC are associated with distinct immune profiles. We investigated the immune cell infiltrate of photo-damaged skin, IEC, and SCC tissue using 10-colour flow cytometry following fresh lesion digest. We found that IEC lesions contain higher percentages of CD3+ T-cells than photo-damaged skin, however, the abundance of CD3-CD56+ Natural Killer (NK cells, CD11c+HLA-DR+ conventional Dendritic Cells (cDC, BDCA-2+HLA-DR+ plasmacytoid DC (pDC, FoxP3+ Regulatory T-cells (T-reg, Vα24+Vβ11+ invariant NKT-cells, and γδ Tcells did not alter with disease stage. Within the total T-cell population, high percentages of CD4+ T-cells were associated with SCC, yet CD8+ T-cells were less abundant in SCC compared with IEC. Our study demonstrates that while IEC lesions contain a higher proportion of T-cells than SCC lesions in general, SCC lesions specifically display a lower abundance of CD8+ T-cells than IEC. We propose that differences in CD8+ T-cell abundance contribute critically to the different capacity of SCC and IEC to regress in response to immune modifying topical treatments. Our study also suggests that a high ratio of CD4+ T-cells to CD8+ T-cells may be a immunological diagnostic indicator of late-stage SCC development in immune-competent patients.

Modification and uptake of a cisplatin carbonato complex by Jurkat cells.

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Centerwall, Corey R; Tacka, Kirk A; Kerwood, Deborah J; Goodisman, Jerry; Toms, Bonnie B; Dubowy, Ronald L; Dabrowiak, James C

2006-07-01

The interactions of Jurkat cells with cisplatin, cis-[Pt(15NH3)2Cl2]1, are studied using 1H-15N heteronuclear single quantum coherence (HSQC) NMR and inductively coupled plasma mass spectrometry. We show that Jurkat cells in culture rapidly modify the monocarbonato complex cis-[Pt(15NH3)2(CO3)Cl]- (4), a cisplatin species that forms in culture media and probably also in blood. Analysis of the HSQC NMR peak intensity for 4 in the presence of different numbers of Jurkat cells reveals that each cell is capable of modifying 0.0028 pmol of 4 within approximately 0.6 h. The amounts of platinum taken up by the cell, weakly bound to the cell surface, remaining in the culture medium, and bound to genomic DNA were measured as functions of time of exposure to different concentrations of drug. The results show that most of the 4 that has been modified by the cells remains in the culture medium as a substance of molecular mass <3 kDa, which is HSQC NMR silent, and is not taken up by the cell. These results are consistent with a hitherto undocumented extracellular detoxification mechanism in which the cells rapidly modify 4, which is present in the culture medium, so it cannot bind to the cell. Because there is only a slow decrease in the amount of unmodified 4 remaining in the culture medium after 1 h, -1.1 +/- 0.4 microM h(-1), the cells subsequently lose their ability to modify 4. These observations have important implications for the mechanism of action of cisplatin.

An endogenous aryl hydrocarbon receptor ligand acts on dendritic cells and T cells to suppress experimental autoimmune encephalomyelitis

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Quintana, Francisco J.; Murugaiyan, Gopal; Farez, Mauricio F.; Mitsdoerffer, Meike; Tukpah, Ann-Marcia; Burns, Evan J.; Weiner, Howard L.

2010-01-01

The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) participates in the differentiation of FoxP3+ Treg, Tr1 cells, and IL-17–producing T cells (Th17). Most of our understanding on the role of AHR on the FoxP3+ Treg compartment results from studies using the toxic synthetic chemical 2,3,7,8-tetrachlorodibenzo-p-dioxin. Thus, the physiological relevance of AHR signaling on FoxP3+ Treg in vivo is unclear. We studied mice that carry a GFP reporter in the endogenous foxp3 locus and a mutated AHR protein with reduced affinity for its ligands, and found that AHR signaling participates in the differentiation of FoxP3+ Treg in vivo. Moreover, we found that treatment with the endogenous AHR ligand 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) given parenterally or orally induces FoxP3+ Treg that suppress experimental autoimmune encephalomyelitis. ITE acts not only on T cells, but also directly on dendritic cells to induce tolerogenic dendritic cells that support FoxP3+ Treg differentiation in a retinoic acid-dependent manner. Thus, our work demonstrates that the endogenous AHR ligand ITE promotes the induction of active immunologic tolerance by direct effects on dendritic and T cells, and identifies nontoxic endogenous AHR ligands as potential unique compounds for the treatment of autoimmune disorders. PMID:21068375

FOXP3 is a novel transcriptional repressor for the breast cancer oncogene SKP2.

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Zuo, Tao; Liu, Runhua; Zhang, Huiming; Chang, Xing; Liu, Yan; Wang, Lizhong; Zheng, Pan; Liu, Yang

2007-12-01

S-phase kinase-associated protein 2 (SKP2) is a component of the E3 ubiquitin ligase SKP1-Cul1-Fbox complex. Overexpression of SKP2 results in cell cycle dysregulation and carcinogenesis; however, the genetic lesions that cause this upregulation are poorly understood. We recently demonstrated that forkhead box P3 (FOXP3) is an X-linked breast cancer suppressor and an important repressor of the oncogene ERBB2/HER2. Since FOXP3 suppresses tumor growth regardless of whether the tumors overexpress ERBB2/HER2, additional FOXP3 targets may be involved in its tumor suppressor activity. Here, we show that mammary carcinomas from mice heterozygous for a Foxp3 mutation exhibited increased Skp2 expression. Ectopic expression of FOXP3 in mouse mammary cancer cells repressed SKP2 expression with a corresponding increase in p27 and polyploidy. Conversely, siRNA silencing of the FOXP3 gene in human mammary epithelial cells increased SKP2 expression. We also show that Foxp3 directly interacted with and repressed the Skp2 promoter. Moreover, the analysis of over 200 primary breast cancer samples revealed an inverse correlation between FOXP3 and SKP2 levels. Finally, we demonstrated that downregulation of SKP2 was critical for FOXP3-mediated growth inhibition in breast cancer cells that do not overexpress ERBB2/HER2. Our data provide genetic, biochemical, and functional evidence that FOXP3 is a novel transcriptional repressor for the oncogene SKP2.

MicroRNA 10a marks regulatory T cells

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Jeker, Lukas T; Zhou, Xuyu; Gershberg, Kseniya

2012-01-01

MicroRNAs (miRNAs) are crucial for regulatory T cell (Treg) stability and function. We report that microRNA-10a (miR-10a) is expressed in Tregs but not in other T cells including individual thymocyte subsets. Expression profiling in inbred mouse strains demonstrated that non-obese diabetic (NOD......) mice with a genetic susceptibility for autoimmune diabetes have lower Treg-specific miR-10a expression than C57BL/6J autoimmune resistant mice. Inhibition of miR-10a expression in vitro leads to reduced FoxP3 expression levels and miR-10a expression is lower in unstable "exFoxP3" T cells. Unstable...... and phenotype of natural Treg nor the capacity of conventional T cells to induce FoxP3 in response to TGFβ, RA, or a combination of the two. Thus, miR-10a is selectively expressed in Treg but inhibition by antagomiRs or genetic ablation resulted in discordant effects on FoxP3....

Kaempferol Promotes Transplant Tolerance by Sustaining CD4+FoxP3+ Regulatory T Cells in the Presence of Calcineurin Inhibitor.

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Zeng, Y Q; Liu, X S; Wu, S; Zou, C; Xie, Q; Xu, S M; Jin, X W; Li, W; Zhou, A; Dai, Z

2015-07-01

Calcineurin inhibitor cyclosporine is widely used as an immunosuppressant in clinic. However, mounting evidence has shown that cyclosporine hinders tolerance induction by dampening Tregs. Therefore, it is of paramount importance to overcome this pitfall. Kaempferol was reported to inhibit DC function. Here, we found that kaempferol delayed islet allograft rejection. Combination of kaempferol and low-dose, but not high-dose, of cyclosporine induced allograft tolerance in majority of recipient mice. Although kaempferol plus either dose of cyclosporine largely abrogated proliferation of graft-infiltrating T cells and their CTL activity, both proliferation and CTL activity in mice treated with kaempferol plus low-dose, but not high-dose, cyclosporine reemerged rapidly upon treatment withdrawal. Kaempferol increased CD4+FoxP3+ Tregs both in transplanted mice and in vitro, likely by suppressing DC maturation and their IL-6 expression. Reduction in Tregs by low dose of cyclosporine was reversed by kaempferol. Kaempferol-induced Tregs exhibited both allospecific and non-allospecific suppression. Administering IL-6 abrogated allograft tolerance induced by kaempferol and cyclosporine via diminishing CD4+FoxP3+ Tregs. Thus, for the first time, we demonstrated that kaempferol promotes transplant tolerance in the presence of low dose of cyclosporine, which allows for sufficient Treg generation while minimizing side effects, resulting in much-needed synergy between kaempferol and cyclosporine. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Selection and characterization of T-cell variants lacking molecules involved in T-cell activation (T3 T-cell receptor, T44, and T11): analysis of the functional relationship among different pathways of activation