Perspectives on Regulatory T Cell Therapies

PubMed Central

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

2009-01-01

Summary 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 at different levels, hampered such an approach. Recent identification of the orphan receptor glycoprotein-A repetitions predominant (GARP or LRRC32) as Treg 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 Treg cells and its implications for regulatory T cell therapies in autoimmunity and graft-versus-host disease. PMID:21076548

Perspectives on Regulatory T Cell Therapies.

PubMed

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.

Transiently Reduced PI3K/Akt Activity Drives the Development of Regulatory Function in Antigen-Stimulated Naïve T-Cells

PubMed Central

Hasenberg, Mike; Reichardt, Peter; Gunzer, Matthias

2013-01-01

Regulatory T-cells (Tregs) are central for immune homeostasis and divided in thymus-derived natural Tregs and peripherally induced iTreg. However, while phenotype and function of iTregs are well known, a remarkable lack exists in knowledge about signaling mechanisms leading to their generation from naïve precursors in peripheral tissues. Using antigen specific naïve T-cells from mice, we investigated CD4+ CD25+ FoxP3- iTreg induction during antigen-specific T-cell receptor (TCR) stimulation with weak antigen presenting cells (APC). We show that early signaling pathways such as ADAM-17-activation appeared similar in developing iTreg and effector cells (Teff) and both initially shedded CD62-L. But iTreg started reexpressing CD62-L after 24 h while Teff permanently downmodulated it. Furthermore, between 24 and 72 hours iTreg presented with significantly lower phosphorylation levels of Akt-S473 suggesting lower activity of the PI3K/Akt-axis. This was associated with a higher expression of the Akt hydrophobic motif-specific phosphatase PHLPP1 in iTreg. Importantly, the lack of costimulatory signals via CD28 from weak APC was central for the development of regulatory function in iTreg but not for the reappearance of CD62-L. Thus, T-cells display a window of sensitivity after onset of TCR triggering within which the intensity of the PI3K/Akt signal controls entry into either effector or regulatory pathways. PMID:23874604

Midkine and multiple sclerosis.

PubMed

Takeuchi, Hideyuki

2014-02-01

Multiple sclerosis (MS) is an autoimmune neurological disease characterized by inflammatory demyelination with subsequent neuronal damage in the CNS. MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have been thought as autoreactive Th1 and Th17 cell-mediated diseases. CD4(+) CD25(+) FoxP3(+) regulatory T-cell (Treg) plays a pivotal role in autoimmune tolerance, and tolerogenic dendritic cells (DCreg) drive the development of inducible Treg cells. Thus, a dysfunction in the development of Treg and DCreg leads to the development of autoimmune diseases. However, the factors that regulate Treg and DCreg are largely unknown. We recently showed that removal of midkine (MK) suppressed EAE due to an expansion of the Treg cell population as well as a decrease in the numbers of autoreactive Th1 and Th17 cells. MK decreased the Treg cell population by suppressing the phosphorylation of STAT5, which is essential for the expression of Foxp3, the master transcriptional factor of Treg cell differentiation. Furthermore, MK reduces the DCreg cell population by inhibiting the phosphorylation of STAT3, which is critical for DCreg development. Blockade of MK signalling by a specific RNA aptamer significantly elevated the population of DCreg and Treg cells and ameliorated EAE without detectable adverse effects. Therefore, the inhibition of MK may provide an effective therapeutic strategy against autoimmune diseases including MS. This article is part of a themed section on Midkine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-4. © 2013 The British Pharmacological Society.

Functional and genomic analyses of FOXP3-transduced Jurkat-T cells as regulatory T (Treg)-like cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Joon-Young; Kim, Han-Jong; Hurt, Elaine M.

2007-10-12

FOXP3, a forkhead transcription factor is essential for the development and function of CD4{sup +}CD25{sup +} regulatory T cells (Tregs). In contrast to conversion of murine naive T cells to Tregs by transduction of Foxp3, it is controversial whether ectopic expression of FOXP3 in human CD4{sup +} T cells is sufficient for acquisition of suppressive activity. Here, we show that retroviral transduction of FOXP3 induces a Treg phenotype in human leukemic CD4{sup +} Jurkat-T cells, evidenced by increased expression of Treg-associated cell surface markers as well as inhibition of cytokine production. Furthermore, FOXP3-transduced Jurkat-T cells suppress the proliferation of humanmore » CD4{sup +}CD25{sup -} T cells. Additionally, DNA microarray analysis identifies Treg-related genes regulated by FOXP3. Our study demonstrates that enforced expression of FOXP3 confers Treg-like properties on Jurkat-T cells, which can be a convenient and efficient Treg-like cell model for further study to identify Treg cell surface markers and target genes regulated by FOXP3.« less

Tumor-associated macrophages recruit CCR6+ regulatory T cells and promote the development of colorectal cancer via enhancing CCL20 production in mice.

PubMed

Liu, Jinlin; Zhang, Ning; Li, Qun; Zhang, Weiwei; Ke, Fang; Leng, Qibin; Wang, Hong; Chen, Jinfei; Wang, Honglin

2011-04-29

Tumor-associated macrophages (TAMs) remodel the colorectal cancer (CRC) microenvironment. Yet, findings on the role of TAMs in CRC seem to be contradictory compared with other cancers. FoxP3(+) regulatory T (Treg)-cells dominantly infiltrate CRC. However, the underlying molecular mechanism in which TAMs may contribute to the trafficking of Treg-cells to the tumor mass remains unknown. CRC was either induced by N-methyl-N-nitrosourea (MNU) and H. pylori or established by subcutaneous injection of mouse colorectal tumor cell line (CMT93) in mice. CMT93 cells were co-cultured with primary macrophages in a transwell apparatus. Recruitment of FoxP3 green fluorescence protein positive (FoxP3(GFP+)) Treg-cells was assessed using the IVIS Imaging System or immunofluorescence staining. A role for macrophages in trafficking of Treg-cells and in the development of CRC was investigated in CD11b diphtheria toxin receptor (CD11b-DTR) transgenic C57BL/6J mice in which macrophages can be selectively depleted. Treg-cells remarkably infiltrated solid tumor, and predominantly expressed the homing chemokine receptor (CCR) 6 in the induced CRC model. Both CMT93 cancer cells and macrophages produced a large amount of CCL20, the sole ligand of CCR6 in vitro and in vivo. Injection of recombinant mouse CCL20 into tumor sites promoted its development with a marked recruitment of Treg-cells in the graft CRC model. Conditional macrophage ablation decreased CCL20 levels, blocked Treg-cell recruitment and inhibited tumor growth in CD11b-DTR mice grafted with CMT93. TAMs recruit CCR6(+) Treg-cells to tumor mass and promote its development via enhancing the production of CCL20 in a CRC mouse model.

In vivo Expansion of Naïve CD4+CD25high FOXP3+ Regulatory T Cells in Patients with Colorectal Carcinoma after IL-2 Administration

PubMed Central

Beyer, Marc; Schumak, Beatrix; Weihrauch, Martin R.; Andres, Bettina; Giese, Thomas; Endl, Elmar; Knolle, Percy A.; Classen, Sabine; Limmer, Andreas; Schultze, Joachim L.

2012-01-01

Regulatory T cells (Treg cells) are increased in context of malignancies and their expansion can be correlated with higher disease burden and decreased survival. Initially, interleukin 2 (IL-2) has been used as T-cell growth factor in clinical vaccination trials. In murine models, however, a role of IL-2 in development, differentiation, homeostasis, and function of Treg cells was established. In IL-2 treated cancer patients a further Treg-cell expansion was described, yet, the mechanism of expansion is still elusive. Here we report that functional Treg cells of a naïve phenotype - as determined by CCR7 and CD45RA expression - are significantly expanded in colorectal cancer patients. Treatment of 15 UICC stage IV colorectal cancer patients with IL-2 in a phase I/II peptide vaccination trial further enlarges the already increased naïve Treg-cell pool. Higher frequencies of T-cell receptor excision circles in naïve Treg cells indicate IL-2 dependent thymic generation of naïve Treg cells as a mechanism leading to increased frequencies of Treg cells post IL-2 treatment in cancer patients. This finding could be confirmed in naïve murine Treg cells after IL-2 administration. These results point to a more complex regulation of Treg cells in context of IL-2 administration. Future strategies therefore might aim at combining IL-2 therapy with novel strategies to circumvent expansion and differentiation of naïve Treg cells. PMID:22276195

The Effects of TLR Activation on T-Cell Development and Differentiation

PubMed Central

Jin, Bo; Sun, Tao; Yu, Xiao-Hong; Yang, Ying-Xiang; Yeo, Anthony E. T.

2012-01-01

Invading pathogens have unique molecular signatures that are recognized by Toll-like receptors (TLRs) resulting in either activation of antigen-presenting cells (APCs) and/or costimulation of T cells inducing both innate and adaptive immunity. TLRs are also involved in T-cell development and can reprogram Treg cells to become helper cells. T cells consist of various subsets, that is, Th1, Th2, Th17, T follicular helper (Tfh), cytotoxic T lymphocytes (CTLs), regulatory T cells (Treg) and these originate from thymic progenitor thymocytes. T-cell receptor (TCR) activation in distinct T-cell subsets with different TLRs results in differing outcomes, for example, activation of TLR4 expressed in T cells promotes suppressive function of regulatory T cells (Treg), while activation of TLR6 expressed in T cells abrogates Treg function. The current state of knowledge of regarding TLR-mediated T-cell development and differentiation is reviewed. PMID:22737174

In Situ Patrolling of Regulatory T Cells Is Essential for Protecting Autoimmune Exocrinopathy

PubMed Central

Ishimaru, Naozumi; Nitta, Takeshi; Arakaki, Rieko; Yamada, Akiko; Lipp, Martin; Takahama, Yousuke; Hayashi, Yoshio

2010-01-01

Background Migration of T cells, including regulatory T (Treg) cells, into the secondary lymph organs is critically controlled by chemokines and adhesion molecules. However, the mechanisms by which Treg cells regulate organ-specific autoimmunity via these molecules remain unclear. Although we previously reported autoimmune exocrinopathy resembling Sjögren's syndrome (SS) in the lacrimal and salivary glands from C-C chemokine receptor 7 (CCR7)-deficient mice, it is still unclear whether CCR7 signaling might specifically affect the dynamics and functions of Treg cells in vivo. We therefore investigated the cellular mechanism for suppressive function of Treg cells via CCR7 in autoimmunity using mouse models and human samples. Methods and Findings Patrolling Treg cells were detected in the exocrine organs such as lacrimal and salivary glands from normal mice that tend to be targets for autoimmunity while the Treg cells were almost undetectable in the exocrine glands of CCR7 −/− mice. In addition, we found the significantly increased retention of CD4+CD25+Foxp3+ Treg cells in the lymph nodes of CCR7 −/− mice with aging. Although Treg cell egress requires sphingosine 1-phosphate (S1P), chemotactic function to S1P of CCR7−/− Treg cells was impaired compared with that of WT Treg cells. Moreover, the in vivo suppression activity was remarkably diminished in CCR7 −/− Treg cells in the model where Treg cells were co-transferred with CCR7 −/− CD25-CD4+ T cells into Rag2 −/− mice. Finally, confocal analysis showed that CCR7+Treg cells were detectable in normal salivary glands while the number of CCR7+Treg cells was extremely decreased in the tissues from patients with Sjögren's syndrome. Conclusions These results indicate that CCR7 essentially governs the patrolling functions of Treg cells by controlling the traffic to the exocrine organs for protecting autoimmunity. Characterization of this cellular mechanism could have clinical implications by supporting development of new diagnosis or treatments for the organ-specific autoimmune diseases such as Sjögren's syndrome and clarifying how the local immune system regulates autoimmunity. PMID:20052419

Large-scale Isolation of Highly Pure "Untouched" Regulatory T Cells in a GMP Environment for Adoptive Cell Therapy.

PubMed

Haase, Doreen; Puan, Kia Joo; Starke, Mireille; Lai, Tuck Siong; Soh, Melissa Yan Ling; Karunanithi, Iyswariya; San Luis, Boris; Poh, Tuang Yeow; Yusof, Nurhashikin; Yeap, Chun Hsien; Phang, Chew Yen; Chye, Willis Soon Yuan; Chan, Marieta; Koh, Mickey Boon Chai; Goh, Yeow Tee; Bertin-Maghit, Sebastien; Nardin, Alessandra; Ho, Liam Pock; Rotzschke, Olaf

2015-01-01

Adoptive cell therapy is an emerging treatment strategy for a number of serious diseases. Regulatory T (Treg) cells represent 1 cell type of particular interest for therapy of inflammatory conditions, as they are responsible for controlling unwanted immune responses. Initial clinical trials of adoptive transfer of Treg cells in patients with graft-versus-host disease were shown to be safe. However, obtaining sufficient numbers of highly pure and functional Treg cells with minimal contamination remains a challenge. We developed a novel approach to isolate "untouched" human Treg cells from healthy donors on the basis of negative selection using the surface markers CD49d and CD127. This procedure, which uses an antibody cocktail and magnetic beads for separation in an automated system (RoboSep), was scaled up and adapted to be compatible with good manufacturing practice conditions. With this setup we performed 9 Treg isolations from large-scale leukapheresis samples in a good manufacturing practice facility. These runs yielded sufficient numbers of "untouched" Treg cells for immediate use in clinical applications. The cell preparations consisted of viable highly pure FoxP3-positive Treg cells that were functional in suppressing the proliferation of effector T cells. Contamination with CD4 effector T cells was <10%. All other cell types did not exceed 2% in the final product. Remaining isolation reagents were reduced to levels that are considered safe. Treg cells isolated with this procedure will be used in a phase I clinical trial of adoptive transfer into leukemia patients developing graft-versus-host disease after stem cell transplantation.

Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

PubMed Central

Su, Shicheng; Liao, Jianyou; Liu, Jiang; Huang, Di; He, Chonghua; Chen, Fei; Yang, LinBing; Wu, Wei; Chen, Jianing; Lin, Ling; Zeng, Yunjie; Ouyang, Nengtai; Cui, Xiuying; Yao, Herui; Su, Fengxi; Huang, Jian-dong; Lieberman, Judy; Liu, Qiang; Song, Erwei

2017-01-01

The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4+ T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4+ T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4+ T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4+ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4+ T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4+ T cells that differentiate into Tregs in situ. Inhibiting naive CD4+ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy. PMID:28290464

SLAP deficiency enhances number and function of regulatory T cells preventing chronic autoimmune arthritis in SKG mice.

PubMed

Peterson, Lisa K; Shaw, Laura A; Joetham, Anthony; Sakaguchi, Shimon; Gelfand, Erwin W; Dragone, Leonard L

2011-02-15

To test if manipulating TCR complex-mediated signaling (TCR signaling) could treat autoimmune disease, we generated the double SKG Src-like adapter protein (SLAP) knockout (DSSKO) mouse model. The SKG mutation in ZAP70 and SLAP have opposing functions on the regulation of TCR signaling. The combination of these two mutations alters TCR signaling in the context of a defined genetic background, uniform environmental conditions, and a well-characterized signaling disruption. In contrast to SKG mice, DSSKO mice do not develop zymosan-induced chronic autoimmune arthritis. This arthritis prevention is not due to significant alterations in thymocyte development or repertoire selection but instead enhanced numbers of regulatory T cells (Tregs) and decreased numbers of Th17 cells skewing the ratio of Tregs to autoreactive effector T cells. Treg depletion and/or functional blockade led to the development of arthritis in DSSKO mice. In vitro suppression of effector T cell proliferation was also enhanced, demonstrating that DSSKO mice have increased numbers of Tregs with increased function. Understanding how TCR signals influence development, expansion, and function of Tregs in DSSKO mice could advance our ability to manipulate Treg biology to treat ultimately autoimmune disease.

SLAP Deficiency Enhances Number and Function of Regulatory T Cells Preventing Chronic Autoimmune Arthritis in SKG Mice

PubMed Central

Peterson, Lisa K.; Shaw, Laura A.; Joetham, Anthony; Sakaguchi, Shimon; Gelfand, Erwin W.; Dragone, Leonard L.

2011-01-01

To test if manipulating TCR complex-mediated signaling (TCR signaling) could treat autoimmune disease, we generated the double SKG Src-like adapter protein (SLAP) knockout (DSSKO) mouse model. The SKG mutation in ZAP70 and SLAP have opposing functions on the regulation of TCR signaling. The combination of these two mutations alters TCR signaling in the context of a defined genetic background, uniform environmental conditions, and a well-characterized signaling disruption. In contrast to SKG mice, DSSKO mice do not develop zymosan-induced chronic autoimmune arthritis. This arthritis prevention is not due to significant alterations in thymocyte development or repertoire selection but instead enhanced numbers of regulatory T cells (Tregs) and decreased numbers of Th17 cells skewing the ratio of Tregs to autoreactive effector T cells. Treg depletion and/or functional blockade led to the development of arthritis in DSSKO mice. In vitro suppression of effector T cell proliferation was also enhanced, demonstrating that DSSKO mice have increased numbers of Tregs with increased function. Understanding how TCR signals influence development, expansion, and function of Tregs in DSSKO mice could advance our ability to manipulate Treg biology to treat ultimately autoimmune disease. PMID:21248251

Providence of CD25+ KIR+ CD127- FOXP3- CD8+ T cell subset determines the dynamics of tumor immune surveillance.

PubMed

Chakraborty, Sreeparna; Bhattacharjee, Pushpak; Panda, Abir K; Kajal, Kirti; Bose, Sayantan; Sa, Gaurisankar

2018-05-16

CD8 + T-regulatory cells are progressively emerging as crucial components of immune system. The previous report suggests the presence of FOXP3-positive CD8 + Treg cells, similar to CD4 + Tregs, in cancer patients which produce high levels of IL10 and TGFβ for its immunosuppressive activities. At an early stage of tumor development, we have identified a subset of FOXP3-negative CD8 + CD25 + KIR + CD127 - a Treg-like subset which is essentially IFNγ-positive. However, this early induced CD8 + CD25 + CD127 - T cell subset certainly distinct from the IFNγ + CD8 + T-effecter cells. This CD8 + CD25 + CD127 - T cells are equipped with other FOXP3 - CD8 + Treg cell signature markers and can selectively suppress HLA-E-positive T FH cells in autoimmune condition as well as tumor-induced CD4 + Treg cells. Contrasting to FOXP3-positive CD8 + Tregs, this subset does not inhibit effector T cell proliferation or their functions as they are HLA-E-negative. Adoptive transfer of this early-CD8 + Treg-like subset detained tumor growth and inhibited CD4 + Treg generation that obstacles the immune surveillance and impairs cancer immunotherapy. At the late stage of tumor development, when CD4 + Treg cells dominate tumor-microenvironment, CD4 + Tregs mediate the clonal deletion of this tumor-suppressive FOXP3 - IFNγ + CD8 + CD25 + CD127 - T cells and ensures tumor immune evasion. Our findings suggest that at an early stage of the tumor, this tumor-induced IFNγ-producing FOXP3-negative CD8 + CD25 + CD127 - T cell subset can potentiate immune surveillance by targeting HLA-E-restricted CD4 + Treg cells whereas leaving the effector T cell population unaffected, and hence maneuvering their profile can open up a new avenue in cancer immunotherapy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Tumor-Associated Macrophages Recruit CCR6+ Regulatory T Cells and Promote the Development of Colorectal Cancer via Enhancing CCL20 Production in Mice

PubMed Central

Li, Qun; Zhang, Weiwei; Ke, Fang; Leng, Qibin; Wang, Hong; Chen, Jinfei; Wang, Honglin

2011-01-01

Background Tumor-associated macrophages (TAMs) remodel the colorectal cancer (CRC) microenvironment. Yet, findings on the role of TAMs in CRC seem to be contradictory compared with other cancers. FoxP3+ regulatory T (Treg)-cells dominantly infiltrate CRC. However, the underlying molecular mechanism in which TAMs may contribute to the trafficking of Treg-cells to the tumor mass remains unknown. Methodology/Principal Findings CRC was either induced by N-methyl-N-nitrosourea (MNU) and H. pylori or established by subcutaneous injection of mouse colorectal tumor cell line (CMT93) in mice. CMT93 cells were co-cultured with primary macrophages in a transwell apparatus. Recruitment of FoxP3 green fluorescence protein positive (FoxP3GFP+) Treg-cells was assessed using the IVIS Imaging System or immunofluorescence staining. A role for macrophages in trafficking of Treg-cells and in the development of CRC was investigated in CD11b diphtheria toxin receptor (CD11b-DTR) transgenic C57BL/6J mice in which macrophages can be selectively depleted. Treg-cells remarkably infiltrated solid tumor, and predominantly expressed the homing chemokine receptor (CCR) 6 in the induced CRC model. Both CMT93 cancer cells and macrophages produced a large amount of CCL20, the sole ligand of CCR6 in vitro and in vivo. Injection of recombinant mouse CCL20 into tumor sites promoted its development with a marked recruitment of Treg-cells in the graft CRC model. Conditional macrophage ablation decreased CCL20 levels, blocked Treg-cell recruitment and inhibited tumor growth in CD11b-DTR mice grafted with CMT93. Conclusions/Significance TAMs recruit CCR6+ Treg-cells to tumor mass and promote its development via enhancing the production of CCL20 in a CRC mouse model. PMID:21559338

Comparison of circulating and intratumoral regulatory T cells in patients with renal cell carcinoma.

PubMed

Asma, Gati; Amal, Gorrab; Raja, Marrakchi; Amine, Derouiche; Mohammed, Chebil; Amel, Ben Ammar Elgaaied

2015-05-01

The clear evidence that tumor-infiltrating lymphocytes (TIL) exists in the tumor microenvironment raises the question why renal cell carcinoma (RCC) progresses. Numerous studies support the implication of CD4(+)CD25(high) regulatory T (Treg) cells in RCC development. We aimed in this study to characterize the phenotype and function of circulating and intratumoral Treg cells of RCC patient in order to evaluate their implication in the inhibition of the local antitumor immune response. Our results demonstrate that the proportion of Treg in TIL was, in average, similar to that found in circulating CD4(+) T cells of patients or healthy donors. However, intratumoral Treg exhibit a marked different phenotype when compared with the autologous circulating Treg. A higher CD25 mean level, HLA-DR, Fas, and GITR, and a lower CD45RA expression were observed in intratumoral Treg, suggesting therefore that these cells are effector in the tumor microenvironment. Additionally, intratumoral Treg showed a higher inhibitory function on autologous CD4(+)CD25(-) T cells when compared with circulating Treg that may be explained by an overexpression of FoxP3 transcription factor. These findings suggest that intratumoral Treg could be major actors in the impairment of local antitumor immune response for RCC patients.

Dependence on nuclear factor of activated T-cells (NFAT) levels discriminates conventional T cells from Foxp3+ regulatory T cells

PubMed Central

Vaeth, Martin; Schliesser, Ulrike; Müller, Gerd; Reissig, Sonja; Satoh, Kazuki; Tuettenberg, Andrea; Jonuleit, Helmut; Waisman, Ari; Müller, Martin R.; Serfling, Edgar; Sawitzki, Birgit S.; Berberich-Siebelt, Friederike

2012-01-01

Several lines of evidence suggest nuclear factor of activated T-cells (NFAT) to control regulatory T cells: thymus-derived naturally occurring regulatory T cells (nTreg) depend on calcium signals, the Foxp3 gene harbors several NFAT binding sites, and the Foxp3 (Fork head box P3) protein interacts with NFAT. Therefore, we investigated the impact of NFAT on Foxp3 expression. Indeed, the generation of peripherally induced Treg (iTreg) by TGF-β was highly dependent on NFAT expression because the ability of CD4+ T cells to differentiate into iTreg diminished markedly with the number of NFAT family members missing. It can be concluded that the expression of Foxp3 in TGF-β–induced iTreg depends on the threshold value of NFAT rather than on an individual member present. This is specific for iTreg development, because frequency of nTreg remained unaltered in mice lacking NFAT1, NFAT2, or NFAT4 alone or in combination. Different from expectation, however, the function of both nTreg and iTreg was independent on robust NFAT levels, reflected by less nuclear NFAT in nTreg and iTreg. Accordingly, absence of one or two NFAT members did not alter suppressor activity in vitro or during colitis and transplantation in vivo. This scenario emphasizes an inhibition of high NFAT activity as treatment for autoimmune diseases and in transplantation, selectively targeting the proinflammatory conventional T cells, while keeping Treg functional. PMID:22991461

Glycolysis controls the induction of human regulatory T cells by modulating the expression of FOXP3 exon 2 splicing variants

PubMed Central

De Rosa, Veronica; Galgani, Mario; Porcellini, Antonio; Colamatteo, Alessandra; Santopaolo, Marianna; Zuchegna, Candida; Romano, Antonella; De Simone, Salvatore; Procaccini, Claudio; La Rocca, Claudia; Carrieri, Pietro Biagio; Maniscalco, Giorgia Teresa; Salvetti, Marco; Buscarinu, Maria Chiara; Franzese, Adriana; Mozzillo, Enza; La Cava, Antonio; Matarese, Giuseppe

2016-01-01

Human regulatory T cells (Treg cells) that develop from conventional T cells (Tconv cells) following suboptimal stimulation via the T cell antigen receptor (TCR) (induced Treg cells (iTreg cells)) express the transcription factor Foxp3, are suppressive, and display an active proliferative and metabolic state. Here we found that the induction and suppressive function of iTreg cells tightly depended on glycolysis, which controlled Foxp3 splicing variants containing exon 2 (Foxp3-E2) through the glycolytic enzyme enolase-1. The Foxp3-E2–related suppressive activity of iTreg cells was altered in human autoimmune diseases, including multiple sclerosis and type 1 diabetes, and was associated with impaired glycolysis and signaling via interleukin 2. This link between glycolysis and Foxp3-E2 variants via enolase-1 shows a previously unknown mechanism for controlling the induction and function of Treg cells in health and in autoimmunity. PMID:26414764

Scutellaria flavonoids inhibit tumor-mediated induction of Treg cells via inhibition of TGF-ß1 activity

USDA-ARS?s Scientific Manuscript database

It has become evident that tumor-induced Treg cell activity is mostly responsible for the sub-optimal response to therapeutic vaccines. Development of neo-adjuvant strategies targeting TGF-ß and Treg cell activity is therefore imperative. Scutellaria extracts or constituent flavonoids have shown e...

Requirement of Treg-intrinsic CTLA4/PKCη signaling pathway for suppressing tumor immunity

PubMed Central

Pedros, Christophe; Canonigo-Balancio, Ann J.; Kong, Kok-Fai

2017-01-01

The ability of Tregs to control the development of immune responses is essential for maintaining immune system homeostasis. However, Tregs also inhibit the development of efficient antitumor responses. Here, we explored the characteristics and mechanistic basis of the Treg-intrinsic CTLA4/PKCη signaling pathway that we recently found to be required for contact-dependent Treg-mediated suppression. We show that PKCη is required for the Treg-mediated suppression of tumor immunity in vivo. The presence of PKCη-deficient (Prkch–/–) Tregs in the tumor microenvironment was associated with a significantly increased expression of the costimulatory molecule CD86 on intratumoral CD103+ DCs, enhanced priming of antigen-specific CD8+ T cells, and greater levels of effector cytokines produced by these cells. Similar to mouse Tregs, the GIT/PAK/PIX complex also operated downstream of CTLA4 and PKCη in human Tregs, and GIT2 knockdown in Tregs promoted antitumor immunity. Collectively, our data suggest that targeting the CTLA4/PKCη/GIT/PAK/PIX signaling pathway in Tregs could represent a novel immunotherapeutic strategy to alleviate the negative impact of Tregs on antitumor immune responses. PMID:29212947

Regulation of the expression of GARP/latent-TGF-β1 complexes on mouse T cells and their role in Regulatory T Cell and Th17 differentiation1

PubMed Central

Edwards, Justin P.; Fujii, Hodaka; Zhou, Angela X.; Creemers, John; Unutmaz, Derya; Shevach, Ethan M.

2013-01-01

GARP/LRRC32 has previously been defined as a marker of activated human regulatory T-cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation, but in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on Tregs within the thymus and Treg precursors from the thymus concomitantly express GARP and Foxp3 upon exposure to IL-2. The expression of GARP is independent of TGF-β1 and TGF-β1 loading into GARP and is independent of furin-mediated processing of pro-TGF-β1 to latent TGF-β1. Specific deletion of GARP in CD4+ T cells results in lack of expression of latent-TGF-β1 on activated Tregs. GARP-deficient Tregs develop normally, are present in normal numbers in peripheral tissues, and are fully competent suppressors of the activation of T conventional cells in vitro. Activated Tregs expressing GARP/latent-TGF-β1 complexes are potent inducers of Th17 differentiation in the presence of exogenous IL-6 and inducers of Treg in the presence of IL-2. Induction of both Th17 producing cells and Treg is preferentially induced by Tregs expressing the latent-TGF-β1/GARP complex on their cell surface rather than by secreted latent-TGF-β1. PMID:23645881

Regulation of the expression of GARP/latent TGF-β1 complexes on mouse T cells and their role in regulatory T cell and Th17 differentiation.

PubMed

Edwards, Justin P; Fujii, Hodaka; Zhou, Angela X; Creemers, John; Unutmaz, Derya; Shevach, Ethan M

2013-06-01

GARP/LRRC32 was defined as a marker of activated human regulatory T cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation; however, in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on Tregs within the thymus, and Treg precursors from the thymus concomitantly express GARP and Foxp3 upon exposure to IL-2. The expression of GARP is independent of TGF-β1 and TGF-β1 loading into GARP and is independent of furin-mediated processing of pro-TGF-β1 to latent TGF-β1. Specific deletion of GARP in CD4(+) T cells results in lack of expression of latent TGF-β1 on activated Tregs. GARP-deficient Tregs develop normally, are present in normal numbers in peripheral tissues, and are fully competent suppressors of the activation of conventional T cells in vitro. Activated Tregs expressing GARP/latent TGF-β1 complexes are potent inducers of Th17 differentiation in the presence of exogenous IL-6 and inducers of Treg in the presence of IL-2. Induction of both Th17-producing cells and Tregs is caused preferentially by Tregs expressing the latent TGF-β1/GARP complex on their cell surface rather than by secreted latent TGF-β1.

Interleukin-35 administration counteracts established murine type 1 diabetes--possible involvement of regulatory T cells.

PubMed

Singh, Kailash; Kadesjö, Erik; Lindroos, Julia; Hjort, Marcus; Lundberg, Marcus; Espes, Daniel; Carlsson, Per-Ola; Sandler, Stellan; Thorvaldson, Lina

2015-07-30

The anti-inflammatory cytokine IL-35 is produced by regulatory T (Treg) cells to suppress autoimmune and inflammatory responses. The role of IL-35 in type 1 diabetes (T1D) remains to be answered. To elucidate this, we investigated the kinetics of Treg cell response in the multiple low dose streptozotocin induced (MLDSTZ) T1D model and measured the levels of IL-35 in human T1D patients. We found that Treg cells were increased in MLDSTZ mice. However, the Treg cells showed a decreased production of anti-inflammatory (IL-10, IL-35, TGF-β) and increased pro-inflammatory (IFN-γ, IL-2, IL-17) cytokines, indicating a phenotypic shift of Treg cells under T1D condition. IL-35 administration effectively both prevented development of, and counteracted established MLDSTZ T1D, seemingly by induction of Eos expression and IL-35 production in Treg cells, thus reversing the phenotypic shift of the Treg cells. IL-35 administration reversed established hyperglycemia in NOD mouse model of T1D. Moreover, circulating IL-35 levels were decreased in human T1D patients compared to healthy controls. These findings suggest that insufficient IL-35 levels play a pivotal role in the development of T1D and that treatment with IL-35 should be investigated in treatment of T1D and other autoimmune diseases.

Developing in vitro expanded CD45RA+ regulatory T cells as an adoptive cell therapy for Crohn's disease.

PubMed

Canavan, James B; Scottà, Cristiano; Vossenkämper, Anna; Goldberg, Rimma; Elder, Matthew J; Shoval, Irit; Marks, Ellen; Stolarczyk, Emilie; Lo, Jonathan W; Powell, Nick; Fazekasova, Henrieta; Irving, Peter M; Sanderson, Jeremy D; Howard, Jane K; Yagel, Simcha; Afzali, Behdad; MacDonald, Thomas T; Hernandez-Fuentes, Maria P; Shpigel, Nahum Y; Lombardi, Giovanna; Lord, Graham M

2016-04-01

Thymus-derived regulatory T cells (Tregs) mediate dominant peripheral tolerance and treat experimental colitis. Tregs can be expanded from patient blood and were safely used in recent phase 1 studies in graft versus host disease and type 1 diabetes. Treg cell therapy is also conceptually attractive for Crohn's disease (CD). However, barriers exist to this approach. The stability of Tregs expanded from Crohn's blood is unknown. The potential for adoptively transferred Tregs to express interleukin-17 and exacerbate Crohn's lesions is of concern. Mucosal T cells are resistant to Treg-mediated suppression in active CD. The capacity for expanded Tregs to home to gut and lymphoid tissue is unknown. To define the optimum population for Treg cell therapy in CD, CD4(+)CD25(+)CD127(lo)CD45RA(+) and CD4(+)CD25(+)CD127(lo)CD45RA(-) Treg subsets were isolated from patients' blood and expanded in vitro using a workflow that can be readily transferred to a good manufacturing practice background. Tregs can be expanded from the blood of patients with CD to potential target dose within 22-24 days. Expanded CD45RA(+) Tregs have an epigenetically stable FOXP3 locus and do not convert to a Th17 phenotype in vitro, in contrast to CD45RA(-) Tregs. CD45RA(+) Tregs highly express α4β7 integrin, CD62L and CC motif receptor 7 (CCR7). CD45RA(+) Tregs also home to human small bowel in a C.B-17 severe combined immune deficiency (SCID) xenotransplant model. Importantly, in vitro expansion enhances the suppressive ability of CD45RA(+) Tregs. These cells also suppress activation of lamina propria and mesenteric lymph node lymphocytes isolated from inflamed Crohn's mucosa. CD4(+)CD25(+)CD127(lo)CD45RA(+) Tregs may be the most appropriate population from which to expand Tregs for autologous Treg therapy for CD, paving the way for future clinical trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Developing in vitro expanded CD45RA+ regulatory T cells as an adoptive cell therapy for Crohn's disease

PubMed Central

Canavan, James B; Scottà, Cristiano; Vossenkämper, Anna; Goldberg, Rimma; Elder, Matthew J; Shoval, Irit; Marks, Ellen; Stolarczyk, Emilie; Lo, Jonathan W; Powell, Nick; Fazekasova, Henrieta; Irving, Peter M; Sanderson, Jeremy D; Howard, Jane K; Yagel, Simcha; Afzali, Behdad; MacDonald, Thomas T; Hernandez-Fuentes, Maria P; Shpigel, Nahum Y; Lombardi, Giovanna; Lord, Graham M

2016-01-01

Background and aim Thymus-derived regulatory T cells (Tregs) mediate dominant peripheral tolerance and treat experimental colitis. Tregs can be expanded from patient blood and were safely used in recent phase 1 studies in graft versus host disease and type 1 diabetes. Treg cell therapy is also conceptually attractive for Crohn's disease (CD). However, barriers exist to this approach. The stability of Tregs expanded from Crohn's blood is unknown. The potential for adoptively transferred Tregs to express interleukin-17 and exacerbate Crohn's lesions is of concern. Mucosal T cells are resistant to Treg-mediated suppression in active CD. The capacity for expanded Tregs to home to gut and lymphoid tissue is unknown. Methods To define the optimum population for Treg cell therapy in CD, CD4+CD25+CD127loCD45RA+ and CD4+CD25+CD127loCD45RA− Treg subsets were isolated from patients’ blood and expanded in vitro using a workflow that can be readily transferred to a good manufacturing practice background. Results Tregs can be expanded from the blood of patients with CD to potential target dose within 22–24 days. Expanded CD45RA+ Tregs have an epigenetically stable FOXP3 locus and do not convert to a Th17 phenotype in vitro, in contrast to CD45RA− Tregs. CD45RA+ Tregs highly express α4β7 integrin, CD62L and CC motif receptor 7 (CCR7). CD45RA+ Tregs also home to human small bowel in a C.B-17 severe combined immune deficiency (SCID) xenotransplant model. Importantly, in vitro expansion enhances the suppressive ability of CD45RA+ Tregs. These cells also suppress activation of lamina propria and mesenteric lymph node lymphocytes isolated from inflamed Crohn's mucosa. Conclusions CD4+CD25+CD127loCD45RA+ Tregs may be the most appropriate population from which to expand Tregs for autologous Treg therapy for CD, paving the way for future clinical trials. PMID:25715355

Tregs: Where We Are and What Comes Next?

PubMed

Zhao, Hai; Liao, Xuelian; Kang, Yan

2017-01-01

Regulatory T cells are usually recognized as a specialized subset of CD4 + T cells functioning in establishment and maintenance of immune tolerance. Meanwhile, there is emerging evidence that regulatory T cells (Tregs) are also present in various non-lymphoid tissues, and that they have unique phenotypes credited with activities distinct from regulatory function. Their development and function have been described in plenty of manuscripts in the past two decades. However, with the deepening of research in recent years, emerging evidence revealed some novel mechanisms about how Tregs exert their activities. First, we discuss the expanding family of regulatory lymphocytes briefly and then, try to interpret how fork-head box P3 (Foxp3), a master regulator of the regulatory pathway in the development and function of regulatory T cells, functions. Subsequently, another part of our focus is varieties of tissue Tregs. Next, we primarily discuss recent research on how Tregs work and their faceted functions in terms of soluble mediators, functional proteins, and inhibitory receptors. In particular, unless otherwise noted, the term "Treg" is used here to refer specially to the "CD4 + CD25 + Foxp3 +" regulatory cells.

Protein kinase CK2 enables regulatory T cells to suppress excessive TH2 responses in vivo.

PubMed

Ulges, Alexander; Klein, Matthias; Reuter, Sebastian; Gerlitzki, Bastian; Hoffmann, Markus; Grebe, Nadine; Staudt, Valérie; Stergiou, Natascha; Bohn, Toszka; Brühl, Till-Julius; Muth, Sabine; Yurugi, Hajime; Rajalingam, Krishnaraj; Bellinghausen, Iris; Tuettenberg, Andrea; Hahn, Susanne; Reißig, Sonja; Haben, Irma; Zipp, Frauke; Waisman, Ari; Probst, Hans-Christian; Beilhack, Andreas; Buchou, Thierry; Filhol-Cochet, Odile; Boldyreff, Brigitte; Breloer, Minka; Jonuleit, Helmut; Schild, Hansjörg; Schmitt, Edgar; Bopp, Tobias

2015-03-01

The quality of the adaptive immune response depends on the differentiation of distinct CD4(+) helper T cell subsets, and the magnitude of an immune response is controlled by CD4(+)Foxp3(+) regulatory T cells (Treg cells). However, how a tissue- and cell type-specific suppressor program of Treg cells is mechanistically orchestrated has remained largely unexplored. Through the use of Treg cell-specific gene targeting, we found that the suppression of allergic immune responses in the lungs mediated by T helper type 2 (TH2) cells was dependent on the activity of the protein kinase CK2. Genetic ablation of the β-subunit of CK2 specifically in Treg cells resulted in the proliferation of a hitherto-unexplored ILT3(+) Treg cell subpopulation that was unable to control the maturation of IRF4(+)PD-L2(+) dendritic cells required for the development of TH2 responses in vivo.

Human regulatory T cells do not suppress the antitumor immunity in the bone marrow: a role for bone marrow stromal cells in neutralizing regulatory T cells.

PubMed

Guichelaar, Teun; Emmelot, Maarten E; Rozemuller, Henk; Martini, Bianka; Groen, Richard W J; Storm, Gert; Lokhorst, Henk M; Martens, Anton C; Mutis, Tuna

2013-03-15

Regulatory T cells (Tregs) are potent tools to prevent graft-versus-host disease (GVHD) induced after allogeneic stem cell transplantation or donor lymphocyte infusions. Toward clinical application of Tregs for GVHD treatment, we investigated the impact of Tregs on the therapeutic graft-versus-tumor (GVT) effect against human multiple myeloma tumors with various immunogenicities, progression rates, and localizations in a humanized murine model. Immunodeficient Rag2(-/-)γc(-/-) mice, bearing various human multiple myeloma tumors, were treated with human peripheral blood mononuclear cell (PBMC) alone or together with autologous ex vivo cultured Tregs. Mice were analyzed for the in vivo engraftment, homing of T-cell subsets, development of GVHD and GVT. In additional in vitro assays, Tregs that were cultured together with bone marrow stromal cells were analyzed for phenotype and functions. Treatment with PBMC alone induced variable degrees of antitumor response, depending on the immunogenicity and the growth rate of the tumor. Coinfusion of Tregs did not impair the antitumor response against tumors residing within the bone marrow, irrespective of their immunogenicity or growth rates. In contrast, Tregs readily inhibited the antitumor effect against tumors growing outside the bone marrow. Exploring this remarkable phenomenon, we discovered that bone marrow stroma neutralizes the suppressive activity of Tregs in part via production of interleukin (IL)-1β/IL-6. We furthermore found in vitro and in vivo evidence of conversion of Tregs into IL-17-producing T cells in the bone marrow environment. These results provide new insights into the Treg immunobiology and indicate the conditional benefits of future Treg-based therapies.

Role of regulatory T cell in the pathogenesis of inflammatory bowel disease.

PubMed

Yamada, Akiko; Arakaki, Rieko; Saito, Masako; Tsunematsu, Takaaki; Kudo, Yasusei; Ishimaru, Naozumi

2016-02-21

Regulatory T (Treg) cells play key roles in various immune responses. For example, Treg cells contribute to the complex pathogenesis of inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis during onset or development of that disease. Many animal models of IBD have been used to investigate factors such as pathogenic cytokines, pathogenic bacteria, and T-cell functions, including those of Treg cells. In addition, analyses of patients with IBD facilitate our understanding of the precise mechanism of IBD. This review article focuses on the role of Treg cells and outlines the pathogenesis and therapeutic strategies of IBD based on previous reports.

Tumor evasion of the immune system by converting CD4+CD25- T cells into CD4+CD25+ T regulatory cells: role of tumor-derived TGF-beta.

PubMed

Liu, Victoria C; Wong, Larry Y; Jang, Thomas; Shah, Ali H; Park, Irwin; Yang, Ximing; Zhang, Qiang; Lonning, Scott; Teicher, Beverly A; Lee, Chung

2007-03-01

CD4+CD25+ T regulatory (T(reg)) cells were initially described for their ability to suppress autoimmune diseases in animal models. An emerging interest is the potential role of T(reg) cells in cancer development and progression because they have been shown to suppress antitumor immunity. In this study, CD4+CD25- T cells cultured in conditioned medium (CM) derived from tumor cells, RENCA or TRAMP-C2, possess similar characteristics as those of naturally occurring T(reg) cells, including expression of Foxp3, a crucial transcription factor of T(reg) cells, production of low levels of IL-2, high levels of IL-10 and TGF-beta, and the ability to suppress CD4+CD25- T cell proliferation. Further investigation revealed a critical role of tumor-derived TGF-beta in converting CD4+CD25- T cells into T(reg) cells because a neutralizing Ab against TGF-beta, 1D11, completely abrogated the induction of T(reg) cells. CM from a nontumorigenic cell line, NRP-152, or irradiated tumor cells did not convert CD4+CD25- T cells to T(reg) cells because they produce low levels of TGF-beta in CM. Finally, we observed a reduced tumor burden in animals receiving 1D11. The reduction in tumor burden correlated with a decrease in tumor-derived TGF-beta. Treatment of 1D11 also reduced the conversion of CD4+ T cells into T(reg) cells and subsequent T(reg) cell-mediated suppression of antitumor immunity. In summary, we have demonstrated that tumor cells directly convert CD4+CD25- T cells to T(reg) cells through production of high levels of TGF-beta, suggesting a possible mechanism through which tumor cells evade the immune system.

Mast cells counteract regulatory T-cell suppression through interleukin-6 and OX40/OX40L axis toward Th17-cell differentiation.

PubMed

Piconese, Silvia; Gri, Giorgia; Tripodo, Claudio; Musio, Silvia; Gorzanelli, Andrea; Frossi, Barbara; Pedotti, Rosetta; Pucillo, Carlo E; Colombo, Mario P

2009-09-24

The development of inflammatory diseases implies inactivation of regulatory T (Treg) cells through mechanisms that still are largely unknown. Here we showed that mast cells (MCs), an early source of inflammatory mediators, are able to counteract Treg inhibition over effector T cells. To gain insight into the molecules involved in their interplay, we set up an in vitro system in which all 3 cellular components were put in contact. Reversal of Treg suppression required T cell-derived interleukin-6 (IL-6) and the OX40/OX40L axis. In the presence of activated MCs, concomitant abundance of IL-6 and paucity of Th1/Th2 cytokines skewed Tregs and effector T cells into IL-17-producing T cells (Th17). In vivo analysis of lymph nodes hosting T-cell priming in experimental autoimmune encephalomyelitis revealed activated MCs, Tregs, and Th17 cells displaying tight spatial interactions, further supporting the occurrence of an MC-mediated inhibition of Treg suppression in the establishment of Th17-mediated inflammatory responses.

Two FOXP3(+)CD4(+) T cell subpopulations distinctly control the prognosis of colorectal cancers.

PubMed

Saito, Takuro; Nishikawa, Hiroyoshi; Wada, Hisashi; Nagano, Yuji; Sugiyama, Daisuke; Atarashi, Koji; Maeda, Yuka; Hamaguchi, Masahide; Ohkura, Naganari; Sato, Eiichi; Nagase, Hirotsugu; Nishimura, Junichi; Yamamoto, Hirofumi; Takiguchi, Shuji; Tanoue, Takeshi; Suda, Wataru; Morita, Hidetoshi; Hattori, Masahira; Honda, Kenya; Mori, Masaki; Doki, Yuichiro; Sakaguchi, Shimon

2016-06-01

CD4(+) T cells that express the forkhead box P3 (FOXP3) transcription factor function as regulatory T (Treg) cells and hinder effective immune responses against cancer cells. Abundant Treg cell infiltration into tumors is associated with poor clinical outcomes in various types of cancers. However, the role of Treg cells is controversial in colorectal cancers (CRCs), in which FOXP3(+) T cell infiltration indicated better prognosis in some studies. Here we show that CRCs, which are commonly infiltrated by suppression-competent FOXP3(hi) Treg cells, can be classified into two types by the degree of additional infiltration of FOXP3(lo) nonsuppressive T cells. The latter, which are distinguished from FOXP3(+) Treg cells by non-expression of the naive T cell marker CD45RA and instability of FOXP3, secreted inflammatory cytokines. Indeed, CRCs with abundant infiltration of FOXP3(lo) T cells showed significantly better prognosis than those with predominantly FOXP3(hi) Treg cell infiltration. Development of such inflammatory FOXP3(lo) non-Treg cells may depend on secretion of interleukin (IL)-12 and transforming growth factor (TGF)-β by tissues and their presence was correlated with tumor invasion by intestinal bacteria, especially Fusobacterium nucleatum. Thus, functionally distinct subpopulations of tumor-infiltrating FOXP3(+) T cells contribute in opposing ways to determining CRC prognosis. Depletion of FOXP3(hi) Treg cells from tumor tissues, which would augment antitumor immunity, could thus be used as an effective treatment strategy for CRCs and other cancers, whereas strategies that locally increase the population of FOXP3(lo) non-Treg cells could be used to suppress or prevent tumor formation.

Suppression of Murine Colitis and its Associated Cancer by Carcinoembryonic Antigen-Specific Regulatory T Cells

PubMed Central

Blat, Dan; Zigmond, Ehud; Alteber, Zoya; Waks, Tova; Eshhar, Zelig

2014-01-01

The adoptive transfer of regulatory T cells (Tregs) offers a promising strategy to combat pathologies that are characterized by aberrant immune activation, including graft rejection and autoinflammatory diseases. Expression of a chimeric antigen receptor (CAR) gene in Tregs redirects them to the site of autoimmune activity, thereby increasing their suppressive efficiency while avoiding systemic immunosuppression. Since carcinoembryonic antigen (CEA) has been shown to be overexpressed in both human colitis and colorectal cancer, we treated CEA-transgenic mice that were induced to develop colitis with CEA-specific CAR Tregs. Two disease models were employed: T-cell-transfer colitis as well as the azoxymethane–dextran sodium sulfate model for colitis-associated colorectal cancer. Systemically administered CEA-specific (but not control) CAR Tregs accumulated in the colons of diseased mice. In both model systems, CEA-specific CAR Tregs suppressed the severity of colitis compared to control Tregs. Moreover, in the azoxymethane–dextran sodium sulfate model, CEA-specific CAR Tregs significantly decreased the subsequent colorectal tumor burden. Our data demonstrate that CEA-specific CAR Tregs exhibit a promising potential in ameliorating ulcerative colitis and in hindering colorectal cancer development. Collectively, this study provides a proof of concept for the therapeutic potential of CAR Tregs in colitis patients as well as in other autoimmune inflammatory disorders. PMID:24686242

Regulatory T cells inhibit acute IFN-γ synthesis without blocking T-helper cell type 1 (Th1) differentiation via a compartmentalized requirement for IL-10

PubMed Central

Sojka, Dorothy K.; Fowell, Deborah J.

2011-01-01

CD4+CD25+Forkhead box P3 (Foxp3)+ regulatory T cells (Tregs) control immune responses to self and foreign antigens in secondary lymphoid organs and at tissue sites of inflammation. Tregs can modify the function of many immune cells and have been proposed to block early proliferation, differentiation, and effector function. Acute ablation of Tregs has revealed rapid cytokine production immediately after Treg removal, suggesting that Tregs may regulate effector function acutely rather than regulating the programming for immune function. We developed in vitro and in vivo models that enabled the direct test of Treg regulation of T-helper cell type 1 (Th1) differentiation. CD28 signaling is known to abrogate Treg suppression of IL-2 secretion and proliferation, but our studies show that Treg suppression of IFN-γ during Th1 priming proceeds despite enhanced CD28 signaling. Importantly, during Th1 differentiation, Tregs inhibited early IFN-γ transcription without disrupting expression of Th1-specific T-box transcription factor (Tbet) and Th1 programming. Acute shutoff of effector cytokine production by Tregs was selective for IFN-γ but not TNF-α and was independent of TGF-β and Epstein-Barr virus-induced gene 3. In vivo, Tregs potently controlled CD4 IFN-γ and CD4 effector cell expansion in the lymph node (four- to fivefold reduction) but not Th1 programming, independent of IL-10. Tregs additionally reduced CD4 IFN-γ in the inflamed dermis (twofold reduction) dependent on their production of IL-10. We propose a model for Treg inhibition of effector function based on acute cytokine regulation. Interestingly, Tregs used different regulatory mechanisms to regulate IFN-γ (IL-10–dependent or –independent) subject to the target T-cell stage of activation and its tissue location. PMID:22025707

CD4+ CD25high Foxp3+ regulatory T cells downregulate human Vδ2+ T-lymphocyte function triggered by anti-CD3 or phosphoantigen

PubMed Central

Mahan, C Scott; Thomas, Jeremy J; Boom, W Henry; Rojas, Roxana E

2009-01-01

Vδ2+ T cells, the major circulating T-cell receptor-γδ-positive (TCR-γδ+) T-cell subset in healthy adults, are involved in immunity against many microbial pathogens including Mycobacterium tuberculosis. Vδ2+ T cells recognize small phosphorylated metabolites (phosphoantigens), expand in response to whole M. tuberculosis bacilli, and complement the protective functions of CD4+ T cells. CD4+ CD25high Foxp3+ T cells (Tregs) comprise 5–10% of circulating T cells and are increased in patients with active tuberculosis (TB). We investigated whether, in addition to their known role in suppressing TCR-αβ+ lymphocytes, Tregs suppress Vδ2+ T-cell function. We found that depletion of Tregs from peripheral blood mononuclear cells increased Vδ2+ T-cell expansion in response to M. tuberculosis (H37Ra) in tuberculin-skin-test-positive donors. We developed a suppression assay with fluorescence-activated cell sorting-purified Tregs and Vδ2+ T cells by coincubating the two cell types at a 1 : 1 ratio. The Tregs partially suppressed interferon-γ secretion by Vδ2+ T cells in response to anti-CD3 monoclonal antibody plus interleukin-2 (IL-2). In addition, Tregs downregulated the Vδ2+ T-cell interferon-γ responses induced by phosphoantigen (BrHPP) and IL-2. Under the latter conditions there was no TCR stimulus for Tregs and therefore IL-2 probably triggered suppressor activity. Addition of purified protein derivative (PPD) increased the suppression of Vδ2+ T cells, suggesting that PPD activated antigen-specific Tregs. Our study provides evidence that Tregs suppress both anti-CD3 and antigen-driven Vδ2+ T-cell activation. Antigen-specific Tregs may therefore contribute to the Vδ2+ T-cell functional deficiencies observed in TB. PMID:19019089

Mechanisms of Oral Tolerance.

PubMed

Tordesillas, Leticia; Berin, M Cecilia

2018-02-27

Oral tolerance is a state of systemic unresponsiveness that is the default response to food antigens in the gastrointestinal tract, although immune tolerance can also be induced by other routes, such as the skin or inhalation. Antigen can be acquired directly by intestinal phagocytes, or pass through enterocytes or goblet cell-associated passages prior to capture by dendritic cells (DCs) in the lamina propria. Mucin from goblet cells acts on DCs to render them more tolerogenic. A subset of regulatory DCs expressing CD103 is responsible for delivery of antigen to the draining lymph node and induction of Tregs. These DCs also imprint gastrointestinal homing capacity, allowing the recently primed Tregs to home back to the lamina propria where they interact with macrophages that produce IL-10 and expand. Tregs induced by dietary antigen include Foxp3 + Tregs and Foxp3 - Tregs. In addition to Tregs, T cell anergy can also contribute to oral tolerance. The microbiota plays a key role in the development of oral tolerance, through regulation of macrophages and innate lymphoid cells that contribute to the regulatory phenotype of gastrointestinal dendritic cells. Absence of microbiota is associated with a susceptibility to food allergy, while presence of Clostridia strains can suppress development of food allergy through enhancement of Tregs and intestinal barrier function. It is not clear if feeding of antigens can also induce true immune tolerance after a memory immune response has been generated, but mechanistic studies of oral immunotherapy trials demonstrate shared pathways in oral tolerance and oral immunotherapy, with a role for Tregs and anergy. An important role for IgA and IgG antibodies in development of immune tolerance is also supported by studies of oral tolerance in humans. The elucidation of key pathways in oral tolerance could identify new strategies to increase efficacy of immunotherapy treatments for food allergy.

Minimum Information about T Regulatory Cells: A Step toward Reproducibility and Standardization.

PubMed

Fuchs, Anke; Gliwiński, Mateusz; Grageda, Nathali; Spiering, Rachel; Abbas, Abul K; Appel, Silke; Bacchetta, Rosa; Battaglia, Manuela; Berglund, David; Blazar, Bruce; Bluestone, Jeffrey A; Bornhäuser, Martin; Ten Brinke, Anja; Brusko, Todd M; Cools, Nathalie; Cuturi, Maria Cristina; Geissler, Edward; Giannoukakis, Nick; Gołab, Karolina; Hafler, David A; van Ham, S Marieke; Hester, Joanna; Hippen, Keli; Di Ianni, Mauro; Ilic, Natasa; Isaacs, John; Issa, Fadi; Iwaszkiewicz-Grześ, Dorota; Jaeckel, Elmar; Joosten, Irma; Klatzmann, David; Koenen, Hans; van Kooten, Cees; Korsgren, Olle; Kretschmer, Karsten; Levings, Megan; Marek-Trzonkowska, Natalia Maria; Martinez-Llordella, Marc; Miljkovic, Djordje; Mills, Kingston H G; Miranda, Joana P; Piccirillo, Ciriaco A; Putnam, Amy L; Ritter, Thomas; Roncarolo, Maria Grazia; Sakaguchi, Shimon; Sánchez-Ramón, Silvia; Sawitzki, Birgit; Sofronic-Milosavljevic, Ljiljana; Sykes, Megan; Tang, Qizhi; Vives-Pi, Marta; Waldmann, Herman; Witkowski, Piotr; Wood, Kathryn J; Gregori, Silvia; Hilkens, Catharien M U; Lombardi, Giovanna; Lord, Phillip; Martinez-Caceres, Eva M; Trzonkowski, Piotr

2017-01-01

Cellular therapies with CD4+ T regulatory cells (Tregs) hold promise of efficacious treatment for the variety of autoimmune and allergic diseases as well as posttransplant complications. Nevertheless, current manufacturing of Tregs as a cellular medicinal product varies between different laboratories, which in turn hampers precise comparisons of the results between the studies performed. While the number of clinical trials testing Tregs is already substantial, it seems to be crucial to provide some standardized characteristics of Treg products in order to minimize the problem. We have previously developed reporting guidelines called minimum information about tolerogenic antigen-presenting cells, which allows the comparison between different preparations of tolerance-inducing antigen-presenting cells. Having this experience, here we describe another minimum information about Tregs (MITREG). It is important to note that MITREG does not dictate how investigators should generate or characterize Tregs, but it does require investigators to report their Treg data in a consistent and transparent manner. We hope this will, therefore, be a useful tool facilitating standardized reporting on the manufacturing of Tregs, either for research purposes or for clinical application. This way MITREG might also be an important step toward more standardized and reproducible testing of the Tregs preparations in clinical applications.

Frequencies and role of regulatory T cells in patients with (pre)malignant cervical neoplasia

PubMed Central

Visser, J; Nijman, H W; Hoogenboom, B-N; Jager, P; van Baarle, D; Schuuring, E; Abdulahad, W; Miedema, F; van der Zee, A G; Daemen, T

2007-01-01

Oncogenic human papillomavirus (HPV)-infection is crucial for developing cervical cancer and its precursor lesions [cervical intraepithelial neoplasia (CIN)]. Regulatory T cells (Tregs) might be involved in the failure of the immune system to control the development of HPV-induced cancer. We investigated frequencies, phenotype and activity of Tregs in patients with cervical neoplasia. CIN and cervical cancer patients showed increased CD4+/CD25high T cell frequencies in peripheral blood and CD4+ T cell fraction. These CD4+/CD25high T cells represent Tregs as demonstrated by their low proliferation rate, low interferon (IFN)-γ/interleukin (IL)-10 ratio, high expression of CD45RO, GITR, CTLA-4, forkhead box P3 (FoxP3) and low CD45RA expression. Moreover, in HPV16+ cervical cancer patients, in-vitro depletion of CD25+ T cells resulted in increased IFN-γ T cell responses against HPV16 E6- and E7 peptides. Thus, increased frequencies of Tregs in cervical cancer patients may indeed suppress HPV-specific immunity. Longitudinal analysis of CD4+/CD25high T cell frequencies in patients showed a modest decline 1 year after curative surgery or chemoradiation. This study demonstrates increased frequencies and suppressive activity of Tregs in cervical cancer. These results imply that Tregs may suppress the immune control of cervical neoplasia and furthermore that suppression of immunity by Tregs will be another hurdle to overcome in therapeutic immunization strategies against cervical neoplasia. PMID:17937675

Altered Th17 cells and Th17/regulatory T-cell ratios indicate the subsequent conversion from undifferentiated connective tissue disease to definitive systemic autoimmune disorders.

PubMed

Szodoray, Peter; Nakken, Britt; Barath, Sandor; Csipo, Istvan; Nagy, Gabor; El-Hage, Fadi; Osnes, Liv T; Szegedi, Gyula; Bodolay, Edit

2013-12-01

A shift in the balance between Th17-cells and regulatory T-cells (Treg) is an important feature of systemic autoimmune diseases (SAID), and may also contribute to their development. Hereby, we assessed the distribution of peripheral Th17 and Treg-cells in patients with undifferentiated connective tissue disease (UCTD), the forerunner of SAIDs and followed these parameters during the development towards definitive SAIDs. Fifty-one UCTD patients were investigated and followed-up for 3 years. Flow cytometry was used to identify and follow three cell-populations: Th17-cells (CD4+IL-17+ T-cells), natural regulatory T-cells (CD4(+)CD25(bright)FoxP3(+); nTregs) and IL-10 producing Type-1 regulatory T-cells (CD4+IL-10+ T-cells; Tr1). Altogether 37.3% of these patients progressed into SAIDs. Th17-cells were increased in UCTD vs. controls, which further increased in those, whom developed SAIDs eventually. The Th17/nTreg ratio gradually increased from controls through UCTD patients, reaching the highest values in SAID-progressed patients. Regarding the Th17/Tr1 ratios, a similar tendency was observed moreover Th17/Tr1 could distinguish between UCTD patients with, or without subsequent SAID progression in a very early UCTD stage. Various immunoserological markers showed association with Th17 and Th17/nTreg at baseline, indicating the consecutive development of a distinct SAID. The derailed Th17/Treg balance may contribute to disease progression therefore could function as a prognostic marker. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Intrauterine growth restriction and prematurity influence regulatory T cell development in newborns.

PubMed

Mukhopadhyay, Dhriti; Weaver, Laura; Tobin, Richard; Henderson, Stephanie; Beeram, Madhava; Newell-Rogers, M Karen; Perger, Lena

2014-05-01

The aim of this study was to determine the relationship of birth weight and gestational age with regulatory T cells (Tregs) in cord blood of human newborns. Cord blood mononuclear cells (CBMCs) of 210 newborns were analyzed using flow cytometry to identify Tregs (CD3(+), CD4(+), CD25(high), FoxP3(high)) and measure FoxP3 mean fluorescence intensity (MFI). Suppressive index (SI) was calculated as FoxP3 MFI per Treg. Mode of delivery had no significant effect on Tregs at birth. Term babies with growth restriction had fewer Tregs than their appropriate weight counterparts but equivalent SI. Preterm babies had higher percentages of Tregs, but lower SI than term controls. SI steadily increased through gestation. Intrauterine growth restriction is correlated with fewer circulating Tregs and prematurity with decreased functionality of Tregs compared to term appropriate weight infants. This may have implications in diseases such as necrotizing enterocolitis that disproportionately affect premature and lower birth weight infants. Copyright © 2014 Elsevier Inc. All rights reserved.

Nanoparticle-mediated codelivery of myelin antigen and a tolerogenic small molecule suppresses experimental autoimmune encephalomyelitis

PubMed Central

Yeste, Ada; Nadeau, Meghan; Burns, Evan J.; Weiner, Howard L.; Quintana, Francisco J.

2012-01-01

The immune response is normally controlled by regulatory T cells (Tregs). However, Treg deficits are found in autoimmune diseases, and therefore the induction of functional Tregs is considered a potential therapeutic approach for autoimmune disorders. The activation of the ligand-activated transcription factor aryl hydrocarbon receptor by 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) or other ligands induces dendritic cells (DCs) that promote FoxP3+ Treg differentiation. Here we report the use of nanoparticles (NPs) to coadminister ITE and a T-cell epitope from myelin oligodendrocyte glycoprotein (MOG)35–55 to promote the generation of Tregs by DCs. NP-treated DCs displayed a tolerogenic phenotype and promoted the differentiation of Tregs in vitro. Moreover, NPs carrying ITE and MOG35–55 expanded the FoxP3+ Treg compartment and suppressed the development of experimental autoimmune encephalomyelitis, an experimental model of multiple sclerosis. Thus, NPs are potential new tools to induce functional Tregs in autoimmune disorders. PMID:22745170

The effect of regulatory T-cell depletion on the spectrum of organ-specific autoimmune diseases in nonobese diabetic mice at different ages.

PubMed

Nakahara, Mami; Nagayama, Yuji; Ichikawa, Tatsuki; Yu, Liping; Eisenbarth, George S; Abiru, Norio

2011-09-01

The nonobese diabetic (NOD) mouse spontaneously develops several autoimmune diseases, including type 1 diabetes and to a lesser extent thyroiditis and sialitis. Imbalance between effector T cells (Teffs) and regulatory T cells (Tregs) has recently been proposed as a mechanism for the disease pathogenesis in NOD mice, but previous studies have shown the various outcomes by different timing and methods of Treg-depletion. This study was, therefore, designed to compare the consequences of Treg-depletion by the same method (anti-CD25 antibody) on the spectrum of organ-specific autoimmune diseases in NOD mice of different ages. Treg-depletion by anti-CD25 antibody at 10 days of age accelerated development of all three diseases we examined (insulitis/diabetes, thyroiditis, and sialitis); Treg-depletion at 4 weeks of age accelerated only diabetes but not thyroiditis or sialitis; and Treg-depletion at 12 weeks of age hastened only development of thyroiditis and exhibited little influence on diabetes or sialitis. Increased levels of insulin autoantibodies (IAA) were, however, observed in mice depleted of Tregs at 10 days of age, not in those at 4 weeks. Thus, the consequences of Treg-depletion on the spectrum of organ-specific autoimmune diseases depend on the timing of anti-CD25 antibody injection in NOD mice. Aging gradually tips balance between Teffs and Tregs toward Teff-dominance for diabetes, but this balance for thyroiditis and sialitis likely alters more intricately. Our data also suggest that the levels of IAA are not necessarily correlated with diabetes development.

MicroRNA-31 negatively regulates peripherally derived regulatory T-cell generation by repressing retinoic acid-inducible protein 3

PubMed Central

Zhang, Lingyun; Ke, Fang; Liu, Zhaoyuan; Bai, Jing; Liu, Jinlin; Yan, Sha; Xu, Zhenyao; Lou, Fangzhou; Wang, Hong; Zhu, Huiyuan; Sun, Yang; Cai, Wei; Gao, Yuanyuan; Li, Qun; Yu, Xue-Zhong; Qian, Youcun; Hua, Zichun; Deng, Jiong; Li, Qi-Jing; Wang, Honglin

2015-01-01

Peripherally derived regulatory T (pTreg) cell generation requires T-cell receptor (TCR) signalling and the cytokines TGF-β1 and IL-2. Here we show that TCR signalling induces the microRNA miR-31, which negatively regulates pTreg-cell generation. miR-31 conditional deletion results in enhanced induction of pTreg cells, and decreased severity of experimental autoimmune encephalomyelitis (EAE). Unexpectedly, we identify Gprc5a as a direct target of miR-31. Gprc5a is known as retinoic acid-inducible protein 3, and its deficiency leads to impaired pTreg-cell induction and increased EAE severity. By generating miR-31 and Gprc5a double knockout mice, we show that miR-31 promotes the development of EAE through inhibiting Gprc5a. Thus, our data identify miR-31 and its target Gprc5a as critical regulators for pTreg-cell generation, suggesting a previously unrecognized epigenetic mechanism for dysfunctional Treg cells in autoimmune diseases. PMID:26165721

Binding of hepatitis A virus to its cellular receptor 1 inhibits T-regulatory cell functions in humans.

PubMed

Manangeeswaran, Mohanraj; Jacques, Jérôme; Tami, Cecilia; Konduru, Krishnamurthy; Amharref, Nadia; Perrella, Oreste; Casasnovas, Jose M; Umetsu, Dale T; Dekruyff, Rosemarie H; Freeman, Gordon J; Perrella, Alessandro; Kaplan, Gerardo G

2012-06-01

CD4+ T-regulatory (Treg) cells suppress immune responses and control self-tolerance and immunity to pathogens, cancer, and alloantigens. Most pathogens activate Treg cells to minimize immune-mediated tissue damage and prevent clearance, which promotes chronic infections. However, hepatitis A virus (HAV) temporarily inhibits Treg-cell functions. We investigated whether the interaction of HAV with its cellular receptor 1 (HAVCR1), a T-cell co-stimulatory molecule, inhibits the function of Treg cells to control HAV infection. We studied the effects of HAV interaction with HAVCR1 on human T cells using binding, signal transduction, apoptosis, activation, suppression, cytokine production, and confocal microscopy analyses. Cytokines were analyzed in sera from 14 patients with HAV infection using bead arrays. Human Treg cells constitutively express HAVCR1. Binding of HAV to HAVCR1 blocked phosphorylation of Akt, prevented activation of the T-cell receptor, and inhibited function of Treg cells. At the peak viremia, patients with acute HAV infection had no Treg-cell suppression function, produced low levels of transforming growth factor-β , which limited leukocyte recruitment and survival, and produced high levels of interleukin-22, which prevented liver damage. Interaction between HAV and its receptor HAVCR1 inhibits Treg-cell function, resulting in an immune imbalance that allows viral expansion with limited hepatocellular damage during early stages of infection-a characteristic of HAV pathogenesis. The mechanism by which HAV is cleared in the absence of Treg-cell function could be used as a model to develop anticancer therapies, modulate autoimmune and allergic responses, and prevent transplant rejection. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Development of Virus-Specific CD4+ and CD8+ Regulatory T Cells Induced by Human Herpesvirus 6 Infection

PubMed Central

Wang, Fang; Chi, Jing; Peng, Guangyong; Zhou, Feng; Wang, Jinfeng; Li, Lingyun; Feng, Dongju; Xie, Fangyi; Gu, Bin; Qin, Jian; Chen, Yun

2014-01-01

Human herpesvirus 6 (HHV-6) is an important immunosuppressive and immunomodulatory virus. The mechanisms by which HHV-6 establishes latency and immunosuppression in its host are not well understood. Here we characterized HHV-6-specific T cells in peripheral blood mononuclear cells (PBMCs) from HHV-6-infected donors. Our results showed that HHV-6 infection could induce both CD4+ and CD8+ HHV-6-specific regulatory T (Treg) cells. These HHV-6-specific Treg cells had potent suppressive activity and expressed high levels of Treg-associated molecules CD25, FoxP3, and GITR. Both CD4+ and CD8+ Treg cells secreted gamma interferon (IFN-γ) and interleukin-10 (IL-10) but little or no IL-2, IL-4, or transforming growth factor β (TGF-β). Furthermore, HHV-6-specifc Treg cells not only could suppress naive and HHV-6-specific CD4+ effector T cell immune responses but also could impair dendritic cell (DC) maturation and functions. In addition, the suppressive effects mediated by HHV-6-specific Treg cells were mainly through a cell-to-cell contact-dependent mechanism but not through the identified cytokines. These results suggest that HHV-6 may utilize the induction of Treg cells as a strategy to escape antivirus immune responses and maintain the latency and immunosuppression in infected hosts. PMID:24198406

Fine specificities of natural regulatory T cells after IVIG therapy in patients with Kawasaki disease

PubMed Central

Burns, Jane C.; Touma, Ranim; Song, Yali; Padilla, Robert L.; Tremoulet, Adriana H.; Sidney, John; Sette, Alessandro; Franco, Alessandra

2016-01-01

The activation of natural regulatory T cells (nTreg) recognizing the heavy constant region (Fc) of IgG is an important mechanism of action of intravenous immunoglobulin (IVIG) therapy in Kawasaki disease (KD). Lack of circulating Fc-specific nTreg in the sub-acute phase of KD is correlated with the development of coronary artery abnormalities (CAA). Here, we characterize the fine specificity of nTreg in sub-acute (2- to 8-week post-IVIG) and convalescent (1- to 10-year post-IVIG) KD subjects by testing the immunogenicity of 64 peptides, 15 amino acids in length with a 10 amino acid-overlap spanning the entire Fc protein. About 12 Fc peptides (6 pools of 2 consecutive peptides) were recognized by nTreg in the cohorts studied, including two patients with CAA. To test whether IVIG expands the same nTreg populations that maintain vascular homeostasis in healthy subjects, we compared these results with results obtained in healthy adult controls. Similar nTreg fine specificities were observed in KD patients after IVIG and in healthy donors. These results suggest that T cell fitness rather than T cell clonal deletion or anergy is responsible for the lack of Fc-specific nTreg in KD patients who develop CAA. Furthermore, we found that adolescents and adults who had KD during childhood without developing CAA did not respond to the Fc protein in vitro, suggesting that the nTreg response induced by IVIG in KD patients is short-lived. Our results support the concept that peptide epitopes may be a viable therapeutic approach to expand Fc-specific nTreg and more effectively prevent CAA in KD patients. PMID:25822882

Nitric Oxide Modulates TGF-β–Directive Signals To Suppress Foxp3+ Regulatory T Cell Differentiation and Potentiate Th1 Development

PubMed Central

Lee, Seung-Woo; Choi, Heonsik; Eun, So-Young; Fukuyama, Satoshi; Croft, Michael

2011-01-01

TGF-β can induce Foxp3+ inducible regulatory T cells (Treg) and also synergize with IL-6 and IL-4 to induce Th17 and Th9 cells. We now report that NO modulates TGF-β activity away from Treg but toward the Th1 lineage. NO potentiated Th1 differentiation in the presence of TGF-β in both IL-12–independent and –dependent fashions by augmenting IFN-γ–activated STAT-1 and T-bet. Differentiation into Treg, Th1, and Th17 lineages could be modulated by NO competing with other cofactors, such as IL-6 and retinoic acid. NO antagonized IL-6 to block TGF-β–directed Th17 differentiation, and together with IL-6, NO suppressed Treg development induced by TGF-β and retinoic acid. Furthermore, we show that physiologically produced NO from TNF and inducible NO synthase-producing dendritic cells can contribute to Th1 development predominating over Treg development through a synergistic activity induced when these cells cocluster with conventional dendritic cells presenting Ag to naive Th cells. This illustrates that NO is another cofactor allowing TGF-β to participate in development of multiple Th lineages and suggests a new mechanism by which NO, which is associated with protection against intracellular pathogens, might maintain effective Th1 immunity. PMID:21555530

Treg Cells Protect Dopaminergic Neurons against MPP+ Neurotoxicity via CD47-SIRPA Interaction.

PubMed

Huang, Yan; Liu, Zhan; Cao, Bei-Bei; Qiu, Yi-Hua; Peng, Yu-Ping

2017-01-01

Regulatory T (Treg) cells have been associated with neuroprotection by inhibiting microglial activation in animal models of Parkinson's disease (PD), a progressive neurodegenerative disease characterized by dopaminergic neuronal loss in the nigrostriatal system. Herein, we show that Treg cells directly protect dopaminergic neurons against 1-methyl-4-phenylpyridinium (MPP+) neurotoxicity via an interaction between the two transmembrane proteins CD47 and signal regulatory protein α (SIRPA). Primary ventral mesencephalic (VM) cells or VM neurons were pretreated with Treg cells before MPP+ treatment. Transwell co-culture of Treg cells and VM neurons was used to assess the effects of the Treg cytokines transforming growth factor (TGF)-β1 and interleukin (IL)-10 on dopaminergic neurons. Live cell imaging system detected a dynamic contact of Treg cells with VM neurons that were stained with CD47 and SIRPA, respectively. Dopaminergic neuronal loss, which was assessed by the number of tyrosine hydroxylase (TH)-immunoreactive cells, was examined after silencing CD47 in Treg cells or silencing SIRPA in VM neurons. Treg cells prevented MPP+-induced dopaminergic neuronal loss and glial inflammatory responses. TGF-β1 and IL-10 secreted from Treg cells did not significantly prevent MPP+-induced dopaminergic neuronal loss in transwell co-culture of Treg cells and VM neurons. CD47 and SIRPA were expressed by Treg cells and VM neurons, respectively. CD47-labeled Treg cells dynamically contacted with SIRPA-labeled VM neurons. Silencing CD47 gene in Treg cells impaired the ability of Treg cells to protect dopaminergic neurons against MPP+ toxicity. Similarly, SIRPA knockdown in VM neurons reduced the ability of Treg cell neuroprotection. Rac1/Akt signaling pathway in VM neurons was activated by CD47-SIRPA interaction between Treg cells and the neurons. Inhibiting Rac1/Akt signaling in VM neurons compromised Treg cell neuroprotection. Treg cells protect dopaminergic neurons against MPP+ neurotoxicity by a cell-to-cell contact mechanism underlying CD47-SIRPA interaction and Rac1/Akt activation. © 2017 The Author(s)Published by S. Karger AG, Basel.

IL-33 contributes to sepsis-induced long-term immunosuppression by expanding the regulatory T cell population.

PubMed

Nascimento, Daniele C; Melo, Paulo H; Piñeros, Annie R; Ferreira, Raphael G; Colón, David F; Donate, Paula B; Castanheira, Fernanda V; Gozzi, Aline; Czaikoski, Paula G; Niedbala, Wanda; Borges, Marcos C; Zamboni, Dario S; Liew, Foo Y; Cunha, Fernando Q; Alves-Filho, Jose C

2017-04-04

Patients who survive sepsis can develop long-term immune dysfunction, with expansion of the regulatory T (Treg) cell population. However, how Treg cells proliferate in these patients is not clear. Here we show that IL-33 has a major function in the induction of this immunosuppression. Mice deficient in ST2 (IL-33R) develop attenuated immunosuppression in cases that survive sepsis, whereas treatment of naive wild-type mice with IL-33 induces immunosuppression. IL-33, released during tissue injury in sepsis, activates type 2 innate lymphoid cells, which promote polarization of M2 macrophages, thereby enhancing expansion of the Treg cell population via IL-10. Moreover, sepsis-surviving patients have more Treg cells, IL-33 and IL-10 in their peripheral blood. Our study suggests that targeting IL-33 may be an effective treatment for sepsis-induced immunosuppression.

IL-33 contributes to sepsis-induced long-term immunosuppression by expanding the regulatory T cell population

PubMed Central

Nascimento, Daniele C.; Melo, Paulo H.; Piñeros, Annie R.; Ferreira, Raphael G.; Colón, David F.; Donate, Paula B.; Castanheira, Fernanda V.; Gozzi, Aline; Czaikoski, Paula G.; Niedbala, Wanda; Borges, Marcos C.; Zamboni, Dario S.; Liew, Foo Y.; Cunha, Fernando Q.; Alves-Filho, Jose C.

2017-01-01

Patients who survive sepsis can develop long-term immune dysfunction, with expansion of the regulatory T (Treg) cell population. However, how Treg cells proliferate in these patients is not clear. Here we show that IL-33 has a major function in the induction of this immunosuppression. Mice deficient in ST2 (IL-33R) develop attenuated immunosuppression in cases that survive sepsis, whereas treatment of naive wild-type mice with IL-33 induces immunosuppression. IL-33, released during tissue injury in sepsis, activates type 2 innate lymphoid cells, which promote polarization of M2 macrophages, thereby enhancing expansion of the Treg cell population via IL-10. Moreover, sepsis-surviving patients have more Treg cells, IL-33 and IL-10 in their peripheral blood. Our study suggests that targeting IL-33 may be an effective treatment for sepsis-induced immunosuppression. PMID:28374774

Excessive expression of miR-27 impairs Treg-mediated immunological tolerance

PubMed Central

Cruz, Leilani O.; Hashemifar, Somaye Sadat; Wu, Cheng-Jang; Cho, Sunglim; Nguyen, Duc T.; Lin, Ling-Li; Khan, Aly Azeem

2017-01-01

MicroRNAs (miRs) are tightly regulated in the immune system, and aberrant expression of miRs often results in hematopoietic malignancies and autoimmune diseases. Previously, it was suggested that elevated levels of miR-27 in T cells isolated from patients with multiple sclerosis facilitate disease progression by inhibiting Th2 immunity and promoting pathogenic Th1 responses. Here we have demonstrated that, although mice with T cell–specific overexpression of miR-27 harbor dysregulated Th1 responses and develop autoimmune pathology, these disease phenotypes are not driven by miR-27 in effector T cells in a cell-autonomous manner. Rather, dysregulation of Th1 responses and autoimmunity resulted from a perturbed Treg compartment. Excessive miR-27 expression in murine T cells severely impaired Treg differentiation. Moreover, Tregs with exaggerated miR-27–mediated gene regulation exhibited diminished homeostasis and suppressor function in vivo. Mechanistically, we determined that miR-27 represses several known as well as previously uncharacterized targets that play critical roles in controlling multiple aspects of Treg biology. Collectively, our data show that miR-27 functions as a key regulator in Treg development and function and suggest that proper regulation of miR-27 is pivotal to safeguarding Treg-mediated immunological tolerance. PMID:28067667

Oral administration with diosgenin enhances the induction of intestinal T helper 1-like regulatory T cells in a murine model of food allergy.

PubMed

Huang, Chung-Hsiung; Wang, Chia-Chi; Lin, Yu-Chin; Hori, Masatoshi; Jan, Tong-Rong

2017-01-01

Although the development of T helper (Th)1-like regulatory T (Treg) cells under Th1 inflammatory conditions has been reported, the role of Th1-like Treg cells in Th2 allergic responses remains mostly unclear. We previously demonstrated that diosgenin, the major sapogenin contained in the Chinese yam, attenuated food allergy and augmented Th1 and Treg immune responses. In this study, we hypothesized that diosgenin may enhance the induction of Th1-like Treg cells in the gut of mice with food allergy. Ovalbumin (OVA)-sensitized BALB/c mice were gavaged daily with diosgenin and received repeatedly intragastric ovalbumin challenges to induce intestinal allergic responses. The induction of Foxp3 + Treg cells co-expressing Th1-type transcription factors, cytokines and chemokines in the intestine was examined, and the mRNA expression of the chemokines corresponding to Th1-like Treg cells was measured. Diosgenin administration increased the number of Foxp3 + Treg cells co-expressing Th1 markers, including CCR5, CXCR3, IFN-γ and T-bet in the intestine, and enhanced populations of Foxp3 + IFN-γ + and Foxp3 + T-bet + cells that expressed the regulatory cytokine IL-10 in the Peyer's patches. Diosgenin also augmented the intestinal expression of CXCR3, CCL3, and CXCL10. Concordantly, diosgenin increased the number of CXCR3 + Foxp3 + IL-10 cells in the Peyer's patches. Our data demonstrated the enhanced induction of Th1-like Treg cells in allergic mice treated with diosgenin, providing evidence to suggest a role for Th1-like Treg cells in diosgenin-mediated anti-allergic effects against Th2-type allergy. Copyright © 2016 Elsevier B.V. All rights reserved.

Combining FoxP3 and Helios with GARP/LAP markers can identify expanded Treg subsets in cancer patients.

PubMed

Abd Al Samid, May; Chaudhary, Belal; Khaled, Yazan S; Ammori, Basil J; Elkord, Eyad

2016-03-22

Regulatory T cells (Tregs) comprise numerous heterogeneous subsets with distinct phenotypic and functional features. Identifying Treg markers is critical to investigate the role and clinical impact of various Treg subsets in pathological settings, and also for developing more effective immunotherapies. We have recently shown that non-activated FoxP3-Helios+ and activated FoxP3+/-Helios+ CD4+ T cells express GARP/LAP immunosuppressive markers in healthy donors. In this study we report similar observations in the peripheral blood of patients with pancreatic cancer (PC) and liver metastases from colorectal cancer (LICRC). Comparing levels of different Treg subpopulations in cancer patients and controls, we report that in PC patients, and unlike LICRC patients, there was no increase in Treg levels as defined by FoxP3 and Helios. However, defining Tregs based on GARP/LAP expression showed that FoxP3-LAP+ Tregs in non-activated and activated settings, and FoxP3+Helios+GARP+LAP+ activated Tregs were significantly increased in both groups of patients, compared with controls. This work implies that a combination of Treg-specific markers could be used to more accurately determine expanded Treg subsets and to understand their contribution in cancer settings. Additionally, GARP-/+LAP+ CD4+ T cells made IL-10, and not IFN-γ, and levels of IL-10-secreting CD4+ T cells were elevated in LICRC patients, especially with higher tumor staging. Taken together, our results indicate that investigations of Treg levels in different cancers should consider diverse Treg-related markers such as GARP, LAP, Helios, and others and not only FoxP3 as a sole Treg-specific marker.

The imbalance of Th17/Treg in patients with uterine cervical cancer.

PubMed

Zhang, Yan; Ma, Daoxin; Zhang, Yong; Tian, Yongju; Wang, Xuping; Qiao, Yunbo; Cui, Baoxia

2011-05-12

Th17/Treg was reported to play critical roles in immunoregulation, and its imbalance may lead to autoimmune diseases and allergic reactions. Information on Th17/Treg in cancer bearing hosts is still limited. We examined the expression of IL-17, Foxp3 and IL-10 in uterine cervical cancer (UCC) patients, cervical intraepithelial neoplasia (CIN) patients and healthy controls by flow cytometry and enzyme-linked immunosorbent assay. Interleukin (IL)-17-producing CD4+ cells as Th17 and CD4+CD25+Foxp3+ cells as Treg were expressed as a percentage of the total CD4+ cells. Compared with controls, patients with UCC or CIN had a higher proportion of Th17 cells. UCC patients also revealed a significant increase in Treg number and IL-17 and IL-10 concentrations in plasma, while CIN patients did not. Notably, in UCC patients, the increased Th17 prevalence was associated with clinical stage, lymph node metastases and vasoinvasion, while the increased Treg frequency was associated with tumor differentiation. Remarkably, an attractive imbalance of Th17/Treg was observed in UUC and CIN patients. Furthermore, in UCC patients with lymph node metastases or vasoinvasion, the ratio of Th17/Treg was significantly higher than that in negative patients respectively. Our results indicated a possible role of Th17 in UCC patients correlated to Treg cells, and the imbalance of Th17/Treg may be involved in the development and progression of UCC. Copyright © 2011 Elsevier B.V. All rights reserved.

CAR/FoxP3-engineered T regulatory cells target the CNS and suppress EAE upon intranasal delivery

PubMed Central

2012-01-01

Background Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS). In the murine experimental autoimmune encephalomyelitis (EAE) model of MS, T regulatory (Treg) cell therapy has proved to be beneficial, but generation of stable CNS-targeting Tregs needs further development. Here, we propose gene engineering to achieve CNS-targeting Tregs from naïve CD4 cells and demonstrate their efficacy in the EAE model. Methods CD4+ T cells were modified utilizing a lentiviral vector system to express a chimeric antigen receptor (CAR) targeting myelin oligodendrocyte glycoprotein (MOG) in trans with the murine FoxP3 gene that drives Treg differentiation. The cells were evaluated in vitro for suppressive capacity and in C57BL/6 mice to treat EAE. Cells were administered by intranasal (i.n.) cell delivery. Results The engineered Tregs demonstrated suppressive capacity in vitro and could efficiently access various regions in the brain via i.n cell delivery. Clinical score 3 EAE mice were treated and the engineered Tregs suppressed ongoing encephalomyelitis as demonstrated by reduced disease symptoms as well as decreased IL-12 and IFNgamma mRNAs in brain tissue. Immunohistochemical markers for myelination (MBP) and reactive astrogliosis (GFAP) confirmed recovery in mice treated with engineered Tregs compared to controls. Symptom-free mice were rechallenged with a second EAE-inducing inoculum but remained healthy, demonstrating the sustained effect of engineered Tregs. Conclusion CNS-targeting Tregs delivered i.n. localized to the CNS and efficiently suppressed ongoing inflammation leading to diminished disease symptoms. PMID:22647574

CD16+ monocytes control T-cell subset development in immune thrombocytopenia

PubMed Central

Zhong, Hui; Bao, Weili; Li, Xiaojuan; Miller, Allison; Seery, Caroline; Haq, Naznin; Bussel, James

2012-01-01

Immune thrombocytopenia (ITP) results from decreased platelet production and accelerated platelet destruction. Impaired CD4+ regulatory T-cell (Treg) compartment and skewed Th1 and possibly Th17 responses have been described in ITP patients. The trigger for aberrant T-cell polarization remains unknown. Because monocytes have a critical role in development and polarization of T-cell subsets, we explored the contribution of monocyte subsets in control of Treg and Th development in patients with ITP. Unlike circulating classic CD14hiCD16− subpopulation, the CD16+ monocyte subset was expanded in ITP patients with low platelet counts on thrombopoietic agents and positively correlated with T-cell CD4+IFN-γ+ levels, but negatively with circulating CD4+CD25hiFoxp3+ and IL-17+ Th cells. Using a coculture model, we found that CD16+ ITP monocytes promoted the expansion of IFN-γ+CD4+ cells and concomitantly inhibited the proliferation of Tregs and IL-17+ Th cells. Th-1–polarizing cytokine IL-12, secreted after direct contact of patient T-cell and CD16+ monocytes, was responsible for the inhibitory effect on Treg and IL-17+CD4+ cell proliferation. Our findings are consistent with ITP CD16+ monocytes promoting Th1 development, which in turn negatively regulates IL-17 and Treg induction. This underscores the critical role of CD16+ monocytes in the generation of potentially pathogenic Th responses in ITP. PMID:22915651

Midkine inhibits inducible regulatory T cell differentiation by suppressing the development of tolerogenic dendritic cells.

PubMed

Sonobe, Yoshifumi; Li, Hua; Jin, Shijie; Kishida, Satoshi; Kadomatsu, Kenji; Takeuchi, Hideyuki; Mizuno, Tetsuya; Suzumura, Akio

2012-03-15

Midkine (MK), a heparin-binding growth factor, reportedly contributes to inflammatory diseases, including Crohn's disease and rheumatoid arthritis. We previously showed that MK aggravates experimental autoimmune encephalomyelitis (EAE) by decreasing regulatory CD4(+)CD25(+)Foxp3(+) T cells (Tregs), a population that regulates the development of autoimmune responses, although the precise mechanism remains uncertain. In this article, we show that MK produced in inflammatory conditions suppresses the development of tolerogenic dendritic cells (DCregs), which drive the development of inducible Treg. MK suppressed DCreg-mediated expansion of the CD4(+)CD25(+)Foxp3(+) Treg population. DCregs expressed significantly higher levels of CD45RB and produced significantly less IL-12 compared with conventional dendritic cells. However, MK downregulated CD45RB expression and induced IL-12 production by reducing phosphorylated STAT3 levels via src homology region 2 domain-containing phosphatase-2 in DCreg. Inhibiting MK activity with anti-MK RNA aptamers, which bind to the targeted protein to suppress the function of the protein, increased the numbers of CD11c(low)CD45RB(+) dendritic cells and Tregs in the draining lymph nodes and suppressed the severity of EAE, an animal model of multiple sclerosis. Our results also demonstrated that MK was produced by inflammatory cells, in particular, CD4(+) T cells under inflammatory conditions. Taken together, these results suggest that MK aggravates EAE by suppressing DCreg development, thereby impairing the Treg population. Thus, MK is a promising therapeutic target for various autoimmune diseases.

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

PubMed

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.

Patients with posttraumatic stress disorder exhibit an altered phenotype of regulatory T cells

PubMed Central

2014-01-01

Background Regulatory T cells (Tregs) play a key role in immune homeostasis in vivo. Tregs have a critical role in preventing the development of autoimmune diseases and defects in Treg function are implicated in various autoimmune disorders. Individuals with posttraumatic stress disorder (PTSD) have higher prevalence of autoimmune disorders than the general population. We hypothesized that war veterans with PTSD would exhibit a decreased number and/or altered phenotype of Tregs. Methods We analyzed peripheral blood mononuclear cells (PBMCs) of patients with PTSD (N = 21) (mean age = 45.9) and age-matched healthy controls (N = 23) (mean age = 45.7) to determine the proportion of Tregs and their phenotype according to the expression of CD127 and HLA-DR markers which describe the differentiation stages of Tregs. In addition, we analyzed the expression of membrane ectoenzyme CD39 on Tregs of the study groups, an important component of the suppressive machinery of Tregs. Results We found no differences in the proportion of Tregs between PTSD patients and controls, but PTSD patients had a higher percentage of CD127-HLA-DR- Tregs and a lower percentage of CD127loHLA-DR+ Tregs compared to controls. There was no difference in expression of CD39 on Tregs of the study groups. Conclusions Although the proportions of Tregs in PTSD patients were unchanged, we found that they exhibit a different phenotype of Tregs that might be less suppressive. Impaired differentiation and function of Tregs is likely involved in disruption of immune homeostasis in PTSD. PMID:25670936

Fatal autoimmune hepatitis induced by concurrent loss of naturally arising regulatory T cells and PD-1-mediated signaling.

PubMed

Kido, Masahiro; Watanabe, Norihiko; Okazaki, Taku; Akamatsu, Takuji; Tanaka, Junya; Saga, Kazuyuki; Nishio, Akiyoshi; Honjo, Tasuku; Chiba, Tsutomu

2008-10-01

Because of the lack of animal models developing spontaneous autoimmune hepatitis (AIH), the molecular mechanisms involved in the development of AIH are still unclear. This study aims to examine the regulatory roles of naturally arising CD4(+)CD25(+) regulatory T (Treg) cells and programmed cell death 1 (PD-1)-mediated signaling in the development of AIH. To induce a concurrent loss of Treg cells and PD-1-mediated signaling, neonatal thymectomy (NTx), which severely reduces the number of Treg cells, was performed on PD-1(-/-) mice. After the NTx, we performed histologic examination, assessed autoantibody production and infiltrating cells in the liver, and conducted adoptive transfer experiments. In contrast to NTx mice and PD-1(-/-) mice, NTx-PD-1(-/-) mice produced antinuclear antibodies and developed fatal hepatitis characterized by a CD4(+) and CD8(+) T-cell infiltration invading the parenchyma with massive lobular necrosis. Induction of AIH in NTx-PD-1(-/-) mice was suppressed by transfer of Treg cells, even derived from PD-1(-/-) mice. Transfer of total but not CD4(+) T-cell-depleted splenocytes from NTx-PD-1(-/-) mice into RAG2(-/-) mice induced the development of severe hepatitis. In contrast, the transfer of CD8(+) T-cell-depleted splenocytes triggered only mononuclear infiltrates without massive necrosis of the parenchyma. NTx-PD-1(-/-) mice are the first mouse model of spontaneous fatal AIH. The concurrent loss of Treg cells and PD-1-mediated signaling can induce the development of fatal AIH. Autoreactive CD4(+) T cells are essential for induction of AIH, whereas CD8(+) T cells play an important role in progression to fatal hepatic damage.

The imbalance between regulatory and IL-17-secreting CD4⁺T cells in multiple-trauma rat.

PubMed

Dai, Heling; Sun, Tiansheng; Liu, Zhi; Zhang, Jianzheng; Zhou, Meng

2013-11-01

It has been well recognised that a deficit of numbers and function of CD4(+)CD25(+)Foxp3(+)cells (Treg) is attributed to the development of auto-immune diseases, inflammatory diseases, tumour and rejection of transplanted tissue; however, there are controversial data regarding the suppressive effect of Treg cells on the T-cell response in auto-immune diseases. Additionally, interleukin-17 (IL-17)-producing cells (Th17) have a pro-inflammatory role. The balance between Th17 and Treg may be essential for maintaining immune homeostasis and has long been thought as one of the important factors in the development/prevention of auto-immune diseases, inflammatory diseases, tumour and rejection of transplanted tissue, but their role in multiple trauma remains unclear. This study aims to investigate whether an imbalance of Treg and Th17 effector cells is characteristic of rats suffering from multiple trauma. Sixty Sprague-Dawley (SD) rats were randomly divided into three groups. The control group (n=20, group I) no received procedures (normal). The sham group (n=20, group II) only received anaesthesia, cannulation and observation. The bilateral femoral shaft fractures with haemorrhagic shock groups (n=20, group III). Rats in groups II and III were killed at the end of 4h after models were established. Peripheral blood samples were collected for assessment of Treg cells, Th17 cells and cytokines (IL-17, IL-6, IL-2, transforming growth factor beta (TGF-β)) and intestine tissue was collected for intestine histological analysis. We observed decreased Treg/Th17 ratios in CD4(+)T cells in rats with multiple trauma and a strong inverse correlation with disease activity (intestinal histological scores). We suggest a role for immune imbalance in the pathogenesis and development of multiple trauma. The alteration of the index of Treg/Th17 cells likely indicates the therapeutic response and progress in the clinic. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Manipulating regulatory T cells: a promising strategy to treat autoimmunity.

PubMed

Zhang, Dunfang; Tu, Eric; Kasagi, Shimpei; Zanvit, Peter; Chen, Qianming; Chen, WanJun

2015-01-01

CD4(+)CD25(+)Foxp3(+)regulatory T cells (Treg cells) are extremely important in maintaining immune tolerance. Manipulation of Treg cells, especially autoantigen-specific Treg cells is a promising approach for treatments of autoimmune disease since Treg cells may provide the advantage of antigen specificity without overall immune suppression. However, the clinical application of Treg cells has long been limited due to low numbers of Treg cells and the difficulty in identifying their antigen specificity. In this review, we summarize studies that demonstrate regression of autoimmune diseases using Treg cells as therapeutics. We also discuss approaches to generate polyclonal and autoantigen-specific Treg cells in vitro and in vivo. We also discuss our recent study that describes a novel approach of generating autoantigen-specific Treg cells in vivo and restoring immune tolerance by two steps apoptosis-antigen therapy.

The GARP/Latent TGF-β1 complex on Treg cells modulates the induction of peripherally derived Treg cells during oral tolerance.

PubMed

Edwards, Justin P; Hand, Timothy W; Morais da Fonseca, Denise; Glass, Deborah D; Belkaid, Yasmine; Shevach, Ethan M

2016-06-01

Treg cells can secrete latent TGF-β1 (LTGF-β1), but can also utilize an alternative pathway for transport and expression of LTGF-β1 on the cell surface in which LTGF-β1 is coupled to a distinct LTGF-β binding protein termed glycoprotein A repetitions predominant (GARP)/LRRC32. The function of the GARP/LTGF-β1 complex has remained elusive. Here, we examine in vivo the roles of GARP and TGF-β1 in the induction of oral tolerance. When Foxp3(-) OT-II T cells were transferred to wild-type recipient mice followed by OVA feeding, the conversion of Foxp3(-) to Foxp3(+) OT-II cells was dependent on recipient Treg cells. Neutralization of IL-2 in the recipient mice also abrogated this conversion. The GARP/LTGF-β1 complex on recipient Treg cells, but not dendritic cell-derived TGF-β1, was required for efficient induction of Foxp3(+) T cells and for the suppression of delayed hypersensitivity. Expression of the integrin αvβ8 by Treg cells (or T cells) in the recipients was dispensable for induction of Foxp3 expression. Transient depletion of the bacterial flora enhanced the development of oral tolerance by expanding Treg cells with enhanced expression of the GARP/LTGF-β1 complex. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Pb exposure attenuates hypersensitivity in vivo by increasing regulatory T cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, Liang; Zhao, Fang; Shen, Xuefeng

Pb is a common environmental pollutant affecting various organs. Exposure of the immune system to Pb leads to immunosuppression or immunodysregulation. Although previous studies showed that Pb exposure can modulate the function of helper T cells, Pb immunotoxicity remains incompletely understood. In this study, we investigated the effect of Pb exposure on T cell development, and the underlying mechanism of Pb-induced suppression of the delayed-type hypersensitivity (DTH) response in vivo. Sprague–Dawley rats were exposed to 300 ppm Pb-acetate solution via the drinking water for six weeks, and we found that Pb exposure significantly increased Pb concentrations in the blood bymore » 4.2-fold (p < 0.05) as compared to those in the control rats. In Pb-exposed rats, the amount of thymic CD4{sup +}CD8{sup −} and peripheral CD4{sup +} T cells was significantly reduced, whereas, CD8{sup +} population was not affected. In contrast to conventional CD4{sup +} T cells, Foxp3{sup +} regulatory T cells (Tregs) were increased in both the thymus and peripheral lymphoid organs of Pb-exposed rats. In line with the increase of Tregs, the DTH response of Pb-exposed rats was markedly suppressed. Depletion of Tregs reversed the suppression of DTH response by Pb-exposed CD4{sup +} T cells in an adoptive transfer model, suggesting a critical role of the increased Tregs in suppressing the DTH response. Collectively, this study revealed that Pb-exposure may upregulate Tregs, thereby leading to immunosuppression. -- Highlights: ► Pb exposure impaired CD4{sup +} thymic T cell development. ► Peripheral T lymphocytes were reduced following Pb exposure. ► Pb exposure increases thymic and peripheral Treg cells in rats. ► Tregs played a critical role in Pb-exposure-induced immune suppression.« less

A Quantitative Increase in Regulatory T Cells Controls Development of Vitiligo

PubMed Central

Chatterjee, Shilpak; Eby, Jonathan; Al-Khami, Amir A.; Soloshchenko, Myroslawa; Kang, Hee-Kap; Kaur, Navtej; Naga, Osama; Murali, Anuradha; Nishimura, Michael I.; Le Poole, I. Caroline; Mehrotra, Shikhar

2014-01-01

T cell cytolytic activity targeting epidermal melanocyte is shown to cause progressive depigmentation and autoimmune vitiligo. Using the recently developed transgenic mice h3TA2 that carry T cell with a HLA-A2 restricted human tyrosinase reactive TCR and develop spontaneous vitiligo from an early age, we addressed the mechanism regulating autoimmune vitiligo. Depigmentation was significantly impaired only in IFN-γ knockout h3TA2 mice but not in TNF-α or perforin knockout h3TA2 mouse strains, confirming a central role for IFN-γ in vitiligo development. Additionally, the regulatory T cells (Treg) were relatively abundant in h3TA2-IFN-γ−/− mice, and depletion of Treg employing anti-CD25 antibody fully restored the depigmentation phenotype in h3TA2-IFN-γ−/− mice mediated in part through upregulation of pro-inflammatory cytokines as IL-17and IL-22. Further therapeutic potential of Treg abundance in preventing progressive depigmentation was evaluated by adoptively transferring purified Treg or using rapamycin. Both adoptive transfer of Treg and rapamycin induced lasting remission of vitiligo in mice treated at the onset of disease, or in mice with established disease. This leads us to conclude that reduced regulatory responses are pivotal to the development of vitiligo in disease-prone mice, and that a quantitative increase in the Treg population may be therapeutic for vitiligo patients with active disease. PMID:24366614

Tumor Necrosis Factor-producing T-regulatory Cells Are Associated With Severe Liver Injury in Patients With Acute Hepatitis A.

PubMed

Choi, Yoon Seok; Jung, Min Kyung; Lee, Jeewon; Choi, Seong Jin; Choi, Sung Hoon; Lee, Hyun Woong; Lee, Jong-Joo; Kim, Hyung Joon; Ahn, Sang Hoon; Lee, Dong Hyeon; Kim, Won; Park, Su-Hyung; Huh, Jun R; Kim, Hyoung-Pyo; Park, Jun Yong; Shin, Eui-Cheol

2018-03-01

CD4 + CD25 + Foxp3 + T-regulatory (Treg) cells control immune responses and maintain immune homeostasis. However, under inflammatory conditions, Treg cells produce cytokines that promote inflammation. We investigated production of tumor necrosis factor (TNF) by Treg cells in patients with acute hepatitis A (AHA), and examined the characteristics of these cells and association with clinical factors. We analyzed blood samples collected from 63 patients with AHA at the time of hospitalization (and some at later time points) and 19 healthy donors in South Korea. Liver tissues were collected from patients with fulminant AHA during liver transplantation. Peripheral blood mononuclear cells were isolated from whole blood and lymphocytes were isolated from liver tissues and analyzed by flow cytometry. Cytokine production from Treg cells (CD4 + CD25 + Foxp3 + ) was measured by immunofluorescence levels following stimulation with anti-CD3 and anti-CD28. Epigenetic stability of Treg cells was determined based on DNA methylation patterns. Phenotypes of Treg cells were analyzed by flow cytometry and an RORγt inhibitor, ML-209, was used to inhibit TNF production. Treg cell suppression assay was performed by co-culture of Treg-depleted peripheral blood mononuclear cells s and isolated Treg cells. A higher proportion of CD4 + CD25 + Foxp3 + Treg cells from patients with AHA compared with controls produced TNF upon stimulation with anti-CD3 and anti-CD28 (11.2% vs 2.8%). DNA methylation analysis confirmed the identity of the Treg cells. TNF-producing Treg cells had features of T-helper 17 cells, including up-regulation of RORγt, which was required for TNF production. The Treg cells had reduced suppressive functions compared with Treg cells from controls. The frequency of TNF-producing Treg cells in AHA patients' blood correlated with their serum level of alanine aminotransferase. Treg cells from patients with AHA have altered functions compared with Treg cells from healthy individuals. Treg cells from patients with AHA produce higher levels of TNF, gain features of T-helper 17 cells, and have reduced suppressive activity. The presence of these cells is associated with severe liver injury in patients with AHA. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Maternal allergic disease history affects childhood allergy development through impairment of neonatal regulatory T-cells.

PubMed

Meng, Shan-Shan; Gao, Rong; Yan, Bing-di; Ren, Jin; Wu, Fei; Chen, Peng; Zhang, Jie; Wang, Li-Fang; Xiao, Yuan-Ming; Liu, Jing

2016-09-20

Maternal allergic disease history and impaired regulatory T-cells (Tregs) are critical risk factors for allergy development in children. However, the mechanisms that underlie these risk factors remain poorly defined. Therefore, the aim of this study was to assess whether maternal allergies affect the Tregs of offspring and lead to allergy development in childhood. A total of 332 mothers of healthy newborns (234 from no allergic mothers, 98 from allergic mothers) were recruited to this study. Detailed questionnaires were administered yearly to determine the allergy status of the mothers and the newborns from birth to 3 years of age. Cord blood samples obtained at the time of birth were analysed for Treg counts, as well Treg activity, based on their response to Toll-like receptor (TLR) stimuli such as lipid A (LPA) and peptidoglycans (PPG). Surface markers, associated genes, suppressive capacity, and cytokine levels of Tregs were also measured. Possible correlations between Treg activity and maternal or neonate allergies were assessed. In addition, environmental microbial content and other known risk factors for allergies were measured. Cord blood mononuclear cells (CBMCs) from offspring with allergic mothers showed fewer CD4(+)CD25(+)FOXP3(+) T cells, lower expression levels of associated genes, and reduced cytokine production of interleukin (IL)-10 and interferon-γ (P < 0.05), especially via the PPG-TLR2 pathway. Suppression of effector T cells by Tregs from children of mothers with allergies was impaired, especially IL-13 production by Type 2 T helper (Th2) cells (P = 0.026). Children who developed allergies in the first 3 years of life had lower numbers of CD4(+)CD25(+)FOXP3(+) T cells and reduced FOXP3 expression and IL-10 production as newborns (P < 0.05). Maternal allergic background was identified as a risk factor for allergy development in the children (Odds ratio (OR) = 2.46, 95 % CI = 1.05-5.79); while declining Treg numbers, IL-10 production, and FOXP3 expression in neonates (PPG and LPA stimulated) were identified as independent risk factors for allergic diseases in offspring at 3 years of age after adjusting for maternal allergic history and environmental factors (P < 0.05). Maternal allergy correlated with impaired Tregs in neonates, and this could enhance the susceptibility of offspring to allergic diseases in early childhood due to an imbalance of Th1 and Th2 cells.

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

PubMed

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.

Cerebral regulatory T cells restrain microglia/macrophage-mediated inflammatory responses via IL-10.

PubMed

Xie, Luokun; Choudhury, Gourav Roy; Winters, Ali; Yang, Shao-Hua; Jin, Kunlin

2015-01-01

Forkhead box P3 (Foxp3)(+) regulatory T (Treg) cells maintain the immune tolerance and prevent inflammatory responses in the periphery. However, the presence of Treg cells in the CNS under steady state has not been studied. Here, for the first time, we show a substantial TCRαβ (+) CD4(+) Foxp3(+) T-cell population (cerebral Treg cells) in the rat cerebrum, constituting more than 15% of the cerebral CD4(+) T-cell compartment. Cerebral Treg cells showed an activated/memory phenotype and expressed many Treg-cell signature genes at higher levels than peripheral Treg cells. Consistent with their activated/memory phenotype, cerebral Treg cells robustly restrained the LPS-induced inflammatory responses of brain microglia/macrophages, suggesting a role in maintaining the cerebral homeostasis by inhibiting the neuroinflammation. In addition, brain astrocytes were the helper cells that sustained Foxp3 expression in Treg cells through IL-2/STAT5 signaling, showing that the interaction between astrocytes and Treg cells contributes to the maintenance of Treg-cell identity in the brain. Taken together, our work represents the first study to characterize the phenotypic and functional features of Treg cells in the rat cerebrum. Our data have provided a novel insight for the contribution of Treg cells to the immunosurveillance and immunomodulation in the cerebrum under steady state. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cerebral regulatory T cells restrain microglia/macrophage-mediated inflammatory responses via IL-10

PubMed Central

Xie, Luokun; Choudhury, Gourav Roy; Winters, Ali; Yang, Shao-Hua; Jin, Kunlin

2014-01-01

Forkhead box P3 (Foxp3)+ regulatory T (Treg) cells maintain the immune tolerance and prevent inflammatory responses in the periphery. However, the presence of Treg cells in the central nervous system under steady state has not been studied. Here, for the first time, we show a substantial TCRαβ+CD4+Foxp3+ T-cell population (cerebral Treg cells) in the normal rat cerebrum, constituting more than 15% of the cerebral CD4+ T-cell compartment. Cerebral Treg cells showed an activated/memory phenotype and expressed many Treg-cell signature genes at higher levels than peripheral Treg cells. Consistent with their activated/memory phenotype, cerebral Treg cells robustly restrained the LPS-induced inflammatory responses of brain microglia/macrophages, suggesting a role in maintaining the cerebral homeostasis by inhibiting the neuroinflammation. In addition, brain astrocytes were the helper cells that sustained Foxp3 expression in Treg cells through IL-2/STAT5 signaling, showing that the interaction between astrocytes and Treg cells contributes to the maintenance of Treg-cell identity in the brain. Taken together, our work represents the first study to characterize the phenotypic and functional features of Treg cells in the normal rat cerebrum. Our data have provided a novel insight for the contribution of Treg cells to the immunosurveillance and immunomodulation in the cerebrum under steady state. PMID:25329858

Immune modulation of CD4+CD25+ regulatory T cells by zoledronic acid.

PubMed

Liu, Hsien; Wang, Shih-Han; Chen, Shin-Cheh; Chen, Ching-Ying; Lo, Jo-Lin; Lin, Tsun-Mei

2016-11-25

CD4 + CD25 + regulatory T (Treg) cells suppress tumor immunity by inhibiting immune cells. Manipulation of Treg cells represents a new strategy for cancer treatment. Zoledronic acid (ZA), a nitrogen-containing bisphosphonate, inhibits the expression of receptor activator of nuclear factor kappa-B ligand (RANKL) on osteoblasts to inhibit osteoclastogenesis. In a mouse model of bisphosphonate-related osteonecrosis of the jaw, administration of ZA suppressed Treg-cell activity and activated inflammatory Th17 cells. However, the interaction between ZA and Treg cells remained unclear. This study investigated the immune modulation of Treg cells by ZA. Flow cytometry was used to analyze the phenotypic and immunosuppressive characteristics of Treg cells treated with ZA. Chemotactic migration was evaluated using transwell assays. Quantitative real-time PCR (qRT-PCR) was used to investigate the effect of ZA on the expression of suppressive molecules by Treg cells. Proliferation of isolated Treg cells in culture was inhibited by ZA, although ZA did not induce apoptosis. qRT-PCR and flow cytometry showed that ZA significantly downregulated the expression of CCR4, CTLA4, PD-1 and RANKL on Treg cells. Chemotactic migration and immunosuppressive functions were also significantly attenuated in Treg cells pretreated with ZA, and these effects were dose-dependent. Co-culture with Treg cells significantly increased the migration rate of breast cancer cells, while pretreatment of Treg cells with ZA attenuated this effect. Our findings demonstrated that ZA acted as an immune modulator by significantly inhibiting the expansion, migration, immunosuppressive function and pro-metastatic ability of Treg cells. Immunomodulation of Treg cells by ZA represents a new strategy for cancer therapy.

Adoptive Cell Therapy of Induced Regulatory T Cells Expanded by Tolerogenic Dendritic Cells on Murine Autoimmune Arthritis.

PubMed

Yang, Jie; Liu, Lidong; Yang, Yiming; Kong, Ning; Jiang, Xueyu; Sun, Juan; Xie, Rufeng

2017-01-01

Tolerogenic dendritic cells (tDCs) can expand TGF- β -induced regulatory T cells (iTregs); however, the therapeutic utility of these expanded iTregs in autoimmune diseases remains unknown. We sought to determine the properties of iTregs expanded by mature tolerogenic dendritic cells (iTreg mtDC ) in vitro and explore their potential to ameliorate collagen-induced arthritis (CIA) in a mouse model. After induction by TGF- β and expansion by mature tDCs (mtDCs), the phenotype and proliferation of iTreg mtDC were assessed by flow cytometry. The ability of iTregs and iTreg mtDC to inhibit CD4 + T cell proliferation and suppress Th17 cell differentiation was compared. Following adoptive transfer of iTregs and iTreg mtDC to mice with CIA, the clinical and histopathologic scores, serum levels of IFN- γ , TNF- α , IL-17, IL-6, IL-10, TGF- β and anti-CII antibodies, and the distribution of the CD4 + Th subset were assessed. Compared with iTregs, iTreg mtDC expressed higher levels of Foxp3 and suppressed CD4 + T cell proliferation and Th17 cell differentiation to a greater extent. In vivo, iTreg mtDC reduced the severity and progression of CIA more significantly than iTregs, which was associated with a modulated inflammatory cytokine profile, reduced anti-CII IgG levels, and polarized Treg/Th17 balance. This study highlights the potential therapeutic utility of iTreg mtDC in autoimmune arthritis and should facilitate the future design of iTreg immunotherapeutic strategies.

High frequency of central memory regulatory T cells allows detection of liver recipients at risk of early acute rejection within the first month after transplantation

PubMed Central

Boix-Giner, Francisco; Millan, Olga; San Segundo, David; Muñoz-Cacho, Pedro; Mancebo, Esther; Llorente, Santiago; Rafael-Valdivia, Lourdes; Rimola, Antoni; Fábrega, Emilio; Mrowiec, Anna; Allende, Luis; Minguela, Alfredo; Bolarín, Jose M.; Paz-Artal, Estela; López-Hoyos, Marcos; Brunet, Mercé

2016-01-01

Several studies have analyzed the potential of T regulatory cells (Treg cells) as biomarkers of acute rejection (AR). The aim of the present multicenter study was to correlate the percentage of peripheral Treg cells in liver graft recipients drawn at baseline up to 12 months after transplantation with the presence of AR. The percentage of central memory (cm) Treg cells (CD4+CD25highCD45RO+CD62L+) was monitored at pre-transplant and at 1 and 2 weeks, and 1, 2, 3 and 6 months and 1 year post-transplantation. The same validation standard operating procedures were used in all participating centers. Fifteen patients developed AR (23.4%). Hepatitis C virus recurrence was observed in 16 recipients, who displayed low peripheral blood cmTreg levels compared with patients who did not. A steady increase of cmTregs was observed during the first month after transplantation with statistically significant differences between AR and non-AR patients. The high frequency of memory Treg cells allowed us to monitor rejection episodes during the first month post-transplantation. On the basis of these data, we developed a prediction model for assessing risk of AR that can provide clinicians with useful information for managing patients individually and customizing immunosuppressive therapies. PMID:26270267

Regulatory T Cell and Forkhead Box Protein 3 as Modulators of Immune Homeostasis

PubMed Central

Pereira, Leonn Mendes Soares; Gomes, Samara Tatielle Monteiro; Ishak, Ricardo; Vallinoto, Antonio Carlos Rosário

2017-01-01

The transcription factor forkhead box protein 3 (FOXP3) is an essential molecular marker of regulatory T cell (Treg) development in different microenvironments. Tregs are cells specialized in the suppression of inadequate immune responses and the maintenance of homeostatic tolerance. Studies have addressed and elucidated the role played by FOXP3 and Treg in countless autoimmune and infectious diseases as well as in more specific cases, such as cancer. Within this context, the present article reviews aspects of the immunoregulatory profile of FOXP3 and Treg in the management of immune homeostasis, including issues relating to pathology as well as immune tolerance. PMID:28603524

A robust, good manufacturing practice-compliant, clinical-scale procedure to generate regulatory T cells from patients with amyotrophic lateral sclerosis for adoptive cell therapy.

PubMed

Alsuliman, Abdullah; Appel, Stanley H; Beers, David R; Basar, Rafet; Shaim, Hila; Kaur, Indresh; Zulovich, Jane; Yvon, Eric; Muftuoglu, Muharrem; Imahashi, Nobuhiko; Kondo, Kayo; Liu, Enli; Shpall, Elizabeth J; Rezvani, Katayoun

2016-10-01

Regulatory T cells (Tregs) play a fundamental role in the maintenance of self-tolerance and immune homeostasis. Defects in Treg function and/or frequencies have been reported in multiple disease models. Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting upper and lower motor neurons. Compelling evidence supports a neuroprotective role for Tregs in this disease. Indeed, rapid progression in ALS patients is associated with decreased FoxP3 expression and Treg frequencies. Thus, we propose that strategies to restore Treg number and function may slow disease progression in ALS. In this study, we developed a robust, Good Manufacturing Practice (GMP)-compliant procedure to enrich and expand Tregs from ALS patients. Tregs isolated from these patients were phenotypically similar to those from healthy individuals but were impaired in their ability to suppress T-cell effector function. In vitro expansion of Tregs for 4 weeks in the presence of GMP-grade anti-CD3/CD28 beads, interleukin (IL)-2 and rapamcyin resulted in a 25- to 200-fold increase in their number and restored their immunoregulatory activity. Collectively, our data facilitate and support the implementation of clinical trials of adoptive therapy with ex vivo expanded and highly suppressive Tregs in patients with ALS. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

The Interaction between Regulatory T Cells and NKT Cells in the Liver: A CD1d Bridge Links Innate and Adaptive Immunity

PubMed Central

Webb, Tonya J.; Potter, James P.; Li, Zhiping

2011-01-01

Background/Aims Regulatory T cells (Tregs) and natural killer T (NKT) cells are two distinct lymphocyte subsets that independently regulate hepatic adaptive and innate immunity, respectively. In the current study, we examine the interaction between Tregs and NKT cells to understand the mechanisms of cross immune regulation by these cells. Methods The frequency and function of Tregs were evaluated in wild type and NKT cell deficient (CD1dko) mice. In vitro lymphocyte proliferation and apoptosis assays were performed with NKT cells co-cultured with Tregs. The ability of Tregs to inhibit NKT cells in vivo was examined by adoptive transfer of Tregs in a model of NKT cell mediated hepatitis. Results CD1dko mice have a significant reduction in hepatic Tregs. Although, the Tregs from CD1dko mice remain functional and can suppress conventional T cells, their ability to suppress activation induced NKT cell proliferation and to promote NKT cell apoptosis is greatly diminished. These effects are CD1d dependent and require cell to cell contact. Adoptive transfer of Tregs inhibits NKT cell-mediated liver injury. Conclusions NKT cells promote Tregs, and Tregs inhibit NKT cells in a CD1d dependent manner requiring cell to cell contact. These cross-talk immune regulations provide a linkage between innate and adaptive immunity. PMID:22073248

Regulatory T cells are strong promoters of acute ischemic stroke in mice by inducing dysfunction of the cerebral microvasculature.

PubMed

Kleinschnitz, Christoph; Kraft, Peter; Dreykluft, Angela; Hagedorn, Ina; Göbel, Kerstin; Schuhmann, Michael K; Langhauser, Friederike; Helluy, Xavier; Schwarz, Tobias; Bittner, Stefan; Mayer, Christian T; Brede, Marc; Varallyay, Csanad; Pham, Mirko; Bendszus, Martin; Jakob, Peter; Magnus, Tim; Meuth, Sven G; Iwakura, Yoichiro; Zernecke, Alma; Sparwasser, Tim; Nieswandt, Bernhard; Stoll, Guido; Wiendl, Heinz

2013-01-24

We have recently identified T cells as important mediators of ischemic brain damage, but the contribution of the different T-cell subsets is unclear. Forkhead box P3 (FoxP3)-positive regulatory T cells (Tregs) are generally regarded as prototypic anti-inflammatory cells that maintain immune tolerance and counteract tissue damage in a variety of immune-mediated disorders. In the present study, we examined the role of Tregs after experimental brain ischemia/reperfusion injury. Selective depletion of Tregs in the DEREG mouse model dramatically reduced infarct size and improved neurologic function 24 hours after stroke and this protective effect was preserved at later stages of infarct development. The specificity of this detrimental Treg effect was confirmed by adoptive transfer experiments in wild-type mice and in Rag1(-/-) mice lacking lymphocytes. Mechanistically, Tregs induced microvascular dysfunction in vivo by increased interaction with the ischemic brain endothelium via the LFA-1/ICAM-1 pathway and platelets and these findings were confirmed in vitro. Ablation of Tregs reduced microvascular thrombus formation and improved cerebral reperfusion on stroke, as revealed by ultra-high-field magnetic resonance imaging at 17.6 Tesla. In contrast, established immunoregulatory characteristics of Tregs had no functional relevance. We define herein a novel and unexpected role of Tregs in a primary nonimmunologic disease state.

Feline Glycoprotein A Repetitions Predominant Anchors Transforming Growth Factor Beta on the Surface of Activated CD4+CD25+ Regulatory T Cells and Mediates AIDS Lentivirus-Induced T Cell Immunodeficiency

PubMed Central

Miller, Michelle M.; Fogle, Jonathan E.; Ross, Peter

2013-01-01

Abstract Using the feline immunodeficiency virus (FIV) model for AIDS-lentivirus infection, our laboratory has previously demonstrated that T regulatory (Treg) cell-mediated immune T and B cell dysfunction contributes to lentivirus persistence and chronic disease through membrane bound transforming growth factor beta (mTGFb). Studying Treg cells in the context of infection has been problematic as no inducible marker for activated Treg cells had been identified. However, recent reports in human Treg studies have described a novel protein, glycoprotein A repetitions predominant (GARP), as a unique marker of activated human Treg cells that anchors mTGFb. Herein we extend these studies to the feline Treg system, identifying feline GARP and demonstrating that human and feline GARP proteins are homologous in structure, expression pattern, and ability to form a complex with TGFb. We further demonstrate that GARP and TGFb form a complex on the surface of activated Treg cells and that these GARP+TGFb+ Treg cells are highly efficient suppressor cells. Analysis of expression of this Treg activation marker in the FIV-AIDS model reveals an up-regulation of GARP expressing Treg cells during chronic FIV infection. We demonstrate that the GARP+ Treg cells from FIV-infected cats suppress T helper cells in vivo and that blocking GARP or TGFb eliminates this suppression. These data suggest that GARP is expressed in complex with TGFb on the surface of activated Treg cells and plays an important role in TGFb+ Treg-mediated T cell immune suppression during lentivirus infection. PMID:23373523

Feline glycoprotein A repetitions predominant anchors transforming growth factor beta on the surface of activated CD4(+)CD25(+) regulatory T cells and mediates AIDS lentivirus-induced T cell immunodeficiency.

PubMed

Miller, Michelle M; Fogle, Jonathan E; Ross, Peter; Tompkins, Mary B

2013-04-01

Using the feline immunodeficiency virus (FIV) model for AIDS-lentivirus infection, our laboratory has previously demonstrated that T regulatory (Treg) cell-mediated immune T and B cell dysfunction contributes to lentivirus persistence and chronic disease through membrane bound transforming growth factor beta (mTGFb). Studying Treg cells in the context of infection has been problematic as no inducible marker for activated Treg cells had been identified. However, recent reports in human Treg studies have described a novel protein, glycoprotein A repetitions predominant (GARP), as a unique marker of activated human Treg cells that anchors mTGFb. Herein we extend these studies to the feline Treg system, identifying feline GARP and demonstrating that human and feline GARP proteins are homologous in structure, expression pattern, and ability to form a complex with TGFb. We further demonstrate that GARP and TGFb form a complex on the surface of activated Treg cells and that these GARP(+)TGFb(+) Treg cells are highly efficient suppressor cells. Analysis of expression of this Treg activation marker in the FIV-AIDS model reveals an up-regulation of GARP expressing Treg cells during chronic FIV infection. We demonstrate that the GARP(+) Treg cells from FIV-infected cats suppress T helper cells in vivo and that blocking GARP or TGFb eliminates this suppression. These data suggest that GARP is expressed in complex with TGFb on the surface of activated Treg cells and plays an important role in TGFb(+) Treg-mediated T cell immune suppression during lentivirus infection.

Activated glycoprotein A repetitions predominant (GARP)-expressing regulatory T cells inhibit allergen-induced intestinal inflammation in humanized mice.

PubMed

Eschborn, Melanie; Weigmann, Benno; Reissig, Sonja; Waisman, Ari; Saloga, Joachim; Bellinghausen, Iris

2015-07-01

Recently, we developed a humanized mouse model of allergen-induced IgE-dependent gut inflammation in PBMC-engrafted immunodeficient mice. In the present study, we wanted to investigate the role of regulatory T (Treg) cells and their activation status in this model. Nonobese diabetic-severe combined immunodeficiency-γc(-/-) mice were injected intraperitoneally with human PBMCs from allergic donors together with the respective allergen or NaCl as control in the presence or absence of different concentrations of CD4(+)CD25(+) Treg cells of the same donor. After an additional allergen boost 1 week later, mice were challenged with the allergen rectally on day 21 and gut inflammation was monitored by a high-resolution video mini-endoscopic system evaluating translucency, granularity, fibrin production, vascularity, and stool. Allergen-specific human IgE in mouse sera, which was detectable only in PBMC plus allergen-treated mice, was strongly inhibited by coinjection of Treg cells at a ratio of at least 1:10. Consequently, the presence of Treg cells significantly decreased IgE-dependent allergen-induced gut inflammation after rectal allergen challenge. In addition, Treg cells reduced allergen-specific proliferation and cytokine production of recovered human CD4(+) T cells in vitro. Activation of Treg cells before injection further increased all inhibitory effects. Prevention of gut inflammation also occurred by the administration of glycoprotein A repetitions predominant, a molecule expressed by activated Treg cells, whereas its blockade completely abrogated inhibition by Treg cells. These results demonstrate that allergen-specific gut inflammation in human PBMC-engrafted mice can be avoided by enhancing the numbers or activity of autologous Treg cells, which is of great interest for therapeutic intervention of allergic diseases of the intestine. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

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

PubMed

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.

Specific recruitment of regulatory T cells in ovarian carcinoma fosters immune privilege and predicts reduced survival.

PubMed

Curiel, Tyler J; Coukos, George; Zou, Linhua; Alvarez, Xavier; Cheng, Pui; Mottram, Peter; Evdemon-Hogan, Melina; Conejo-Garcia, Jose R; Zhang, Lin; Burow, Matthew; Zhu, Yun; Wei, Shuang; Kryczek, Ilona; Daniel, Ben; Gordon, Alan; Myers, Leann; Lackner, Andrew; Disis, Mary L; Knutson, Keith L; Chen, Lieping; Zou, Weiping

2004-09-01

Regulatory T (T(reg)) cells mediate homeostatic peripheral tolerance by suppressing autoreactive T cells. Failure of host antitumor immunity may be caused by exaggerated suppression of tumor-associated antigen-reactive lymphocytes mediated by T(reg) cells; however, definitive evidence that T(reg) cells have an immunopathological role in human cancer is lacking. Here we show, in detailed studies of CD4(+)CD25(+)FOXP3(+) T(reg) cells in 104 individuals affected with ovarian carcinoma, that human tumor T(reg) cells suppress tumor-specific T cell immunity and contribute to growth of human tumors in vivo. We also show that tumor T(reg) cells are associated with a high death hazard and reduced survival. Human T(reg) cells preferentially move to and accumulate in tumors and ascites, but rarely enter draining lymph nodes in later cancer stages. Tumor cells and microenvironmental macrophages produce the chemokine CCL22, which mediates trafficking of T(reg) cells to the tumor. This specific recruitment of T(reg) cells represents a mechanism by which tumors may foster immune privilege. Thus, blocking T(reg) cell migration or function may help to defeat human cancer.

Promiscuous Foxp3-cre activity reveals a differential requirement for CD28 in Foxp3⁺ and Foxp3⁻ T cells.

PubMed

Franckaert, Dean; Dooley, James; Roos, Evelyne; Floess, Stefan; Huehn, Jochen; Luche, Herve; Fehling, Hans Joerg; Liston, Adrian; Linterman, Michelle A; Schlenner, Susan M

2015-04-01

Costimulatory signals by CD28 are critical for thymic regulatory T-cell (Treg) development. To determine the functional relevance of CD28 for peripheral Treg post thymic selection, we crossed the widely used Forkhead box protein 3 (Foxp3)-CreYFP mice to mice bearing a conditional Cd28 allele. Treg-specific CD28 deficiency provoked a severe autoimmune syndrome as a result of a strong disadvantage in competitive fitness and proliferation of CD28-deficient Tregs. By contrast, Treg survival and lineage integrity were not affected by the lack of CD28. This data demonstrate that, even after the initial induction requirement, Treg maintain a higher dependency on CD28 signalling than conventional T cells for homeostasis. In addition, we found the Foxp3-CreYFP allele to be a hypomorph, with reduced Foxp3 protein levels. Furthermore, we report here the stochastic activity of the Foxp3-CreYFP allele in non-Tregs, sufficient to recombine some conditional alleles (including Cd28) but not others (including R26-RFP). This hypomorphism and 'leaky' expression of the Foxp3-CreYFP allele should be considered when analysing the conditionally mutated Treg.

The establishment of cow's milk protein allergy in infants is related with a deficit of regulatory T cells (Treg) and vitamin D.

PubMed

Perezabad, Laura; López-Abente, Jacobo; Alonso-Lebrero, Elena; Seoane, Elena; Pion, Marjorie; Correa-Rocha, Rafael

2017-05-01

Cow's milk protein allergy (CMPA) is the most common food allergy in infants. However, little is known about which specific immune mechanisms are related with the CMPA onset. The objective was to investigate which immune alterations constitute differential factors between allergy and tolerance, and hence could be implicated in the CMPA establishment in infants. An extensive analysis of immune subsets, including Treg and cytokine-secreting cells was performed in blood samples from 28 infants younger than 9 mo obtained 1-4 d after the first adverse reaction to milk. Less than 4 d after first allergic reaction, infants who developed CMPA had decreased Treg counts and increased frequency of IL4-secreting CD4 T cells compared to controls. The deficit of Tregs was correlated with decreased serum levels of vitamin D. Values of Tregs, IL4-secreting cells and vitamin D were good predictors of CMPA diagnosis. Basal vitamin D levels in CMPA infants also predicted those CMPA patients developing spontaneous tolerance in the first year. Establishment of CMPA in infants was related with lower Treg and vitamin D levels. These immune alterations would be crucial factors behind the CMPA establishment and they could constitute a therapeutic target for treatment of CMPA.

Adoptive transfer of induced-Treg cells effectively attenuates murine airway allergic inflammation.

PubMed

Xu, Wei; Lan, Qin; Chen, Maogen; Chen, Hui; Zhu, Ning; Zhou, Xiaohui; Wang, Julie; Fan, Huimin; Yan, Chun-Song; Kuang, Jiu-Long; Warburton, David; Togbe, Dieudonnée; Ryffel, Bernhard; Zheng, Song-Guo; Shi, Wei

2012-01-01

Both nature and induced regulatory T (Treg) lymphocytes are potent regulators of autoimmune and allergic disorders. Defects in endogenous Treg cells have been reported in patients with allergic asthma, suggesting that disrupted Treg cell-mediated immunological regulation may play an important role in airway allergic inflammation. In order to determine whether adoptive transfer of induced Treg cells generated in vitro can be used as an effective therapeutic approach to suppress airway allergic inflammation, exogenously induced Treg cells were infused into ovalbumin-sensitized mice prior to or during intranasal ovalbumin challenge. The results showed that adoptive transfer of induced Treg cells prior to allergen challenge markedly reduced airway hyperresponsiveness, eosinophil recruitment, mucus hyper-production, airway remodeling, and IgE levels. This effect was associated with increase of Treg cells (CD4(+)FoxP3(+)) and decrease of dendritic cells in the draining lymph nodes, and with reduction of Th1, Th2, and Th17 cell response as compared to the controls. Moreover, adoptive transfer of induced Treg cells during allergen challenge also effectively attenuate airway inflammation and improve airway function, which are comparable to those by natural Treg cell infusion. Therefore, adoptive transfer of in vitro induced Treg cells may be a promising therapeutic approach to prevent and treat severe asthma.

Adoptive Transfer of Induced-Treg Cells Effectively Attenuates Murine Airway Allergic Inflammation

PubMed Central

Chen, Maogen; Chen, Hui; Zhu, Ning; Zhou, Xiaohui; Wang, Julie; Fan, Huimin; Yan, Chun-Song; Kuang, Jiu-Long; Warburton, David; Togbe, Dieudonnée; Ryffel, Bernhard; Zheng, Song-Guo; Shi, Wei

2012-01-01

Both nature and induced regulatory T (Treg) lymphocytes are potent regulators of autoimmune and allergic disorders. Defects in endogenous Treg cells have been reported in patients with allergic asthma, suggesting that disrupted Treg cell-mediated immunological regulation may play an important role in airway allergic inflammation. In order to determine whether adoptive transfer of induced Treg cells generated in vitro can be used as an effective therapeutic approach to suppress airway allergic inflammation, exogenously induced Treg cells were infused into ovalbumin-sensitized mice prior to or during intranasal ovalbumin challenge. The results showed that adoptive transfer of induced Treg cells prior to allergen challenge markedly reduced airway hyperresponsiveness, eosinophil recruitment, mucus hyper-production, airway remodeling, and IgE levels. This effect was associated with increase of Treg cells (CD4+FoxP3+) and decrease of dendritic cells in the draining lymph nodes, and with reduction of Th1, Th2, and Th17 cell response as compared to the controls. Moreover, adoptive transfer of induced Treg cells during allergen challenge also effectively attenuate airway inflammation and improve airway function, which are comparable to those by natural Treg cell infusion. Therefore, adoptive transfer of in vitro induced Treg cells may be a promising therapeutic approach to prevent and treat severe asthma. PMID:22792275

Tregs: Where We Are and What Comes Next?

PubMed Central

Zhao, Hai; Liao, Xuelian; Kang, Yan

2017-01-01

Regulatory T cells are usually recognized as a specialized subset of CD4+ T cells functioning in establishment and maintenance of immune tolerance. Meanwhile, there is emerging evidence that regulatory T cells (Tregs) are also present in various non-lymphoid tissues, and that they have unique phenotypes credited with activities distinct from regulatory function. Their development and function have been described in plenty of manuscripts in the past two decades. However, with the deepening of research in recent years, emerging evidence revealed some novel mechanisms about how Tregs exert their activities. First, we discuss the expanding family of regulatory lymphocytes briefly and then, try to interpret how fork-head box P3 (Foxp3), a master regulator of the regulatory pathway in the development and function of regulatory T cells, functions. Subsequently, another part of our focus is varieties of tissue Tregs. Next, we primarily discuss recent research on how Tregs work and their faceted functions in terms of soluble mediators, functional proteins, and inhibitory receptors. In particular, unless otherwise noted, the term “Treg” is used here to refer specially to the “CD4+CD25+Foxp3+” regulatory cells. PMID:29225597

Mesenchymal stem cells induce functionally active T-regulatory lymphocytes in a paracrine fashion and ameliorate experimental autoimmune uveitis.

PubMed

Tasso, Roberta; Ilengo, Cristina; Quarto, Rodolfo; Cancedda, Ranieri; Caspi, Rachel R; Pennesi, Giuseppina

2012-02-01

Mesenchymal stem/progenitor cells (MSCs) have regenerative and immunomodulatory properties, exerted by cell-cell contact and in a paracrine fashion. Part of their immunosuppressive activity has been ascribed to their ability to promote the induction of CD4+CD25+FoxP3+ T lymphocytes with regulatory functions (Treg). Here the authors studied the effect of MSCs on the induction of Treg and on the development of autoimmunity, and they examined the possibility that MSC-mediated Treg induction could be attributed to the secretion of soluble factors. The authors induced experimental autoimmune uveitis (EAU) in mice by immunization with the 1-20 peptide of the intraphotoreceptor binding protein. At the same time, some of the animals were treated intraperitoneally with syngeneic MSCs. The authors checked T-cell responses and in vitro Treg conversion by cell proliferation and blocking assays, in cell-cell contact and transwell settings. TGFβ and TGFβ receptor gene expression analyses were performed by real-time PCR. The authors found that a single intraperitoneal injection of MSCs was able to significantly attenuate EAU and that a significantly higher percentage of adaptive Treg was present in MSC-treated mice than in MSC-untreated animals. In vitro blocking of antigen presentation by major histocompatibility complex class II precluded priming and clonal expansion of antigen-specific Treg, whereas blockade of TGFβ impaired the expression of FoxP3, preventing the conversion of CD4+ T cells into functionally active Treg. The authors demonstrated that MSCs can inhibit EAU and that their immunomodulatory function is due at least in part to the induction of antigen-specific Treg in a paracrine fashion by secreting TGFβ.

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

PubMed Central

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

Cell banking for regulatory T cell-based therapy: strategies to overcome the impact of cryopreservation on the Treg viability and phenotype

PubMed Central

Gołąb, Karolina; Grose, Randall; Placencia, Veronica; Wickrema, Amittha; Solomina, Julia; Tibudan, Martin; Konsur, Evelyn; Ciepły, Kamil; Marek-Trzonkowska, Natalia; Trzonkowski, Piotr; Millis, J. Michael; Fung, John; Witkowski, Piotr

2018-01-01

The first clinical trials with adoptive Treg therapy have shown safety and potential efficacy. Feasibility of such therapy could be improved if cells are cryopreserved and stored until optimal timing for infusion. Herein, we report the evaluation of two cell-banking strategies for Treg therapy: 1) cryopreservation of CD4+ cells for subsequent Treg isolation/expansion and 2) cryopreservation of ex-vivo expanded Tregs (CD4+CD25hiCD127lo/- cells). First, we checked how cryopreservation affects cell viability and Treg markers expression. Then, we performed Treg isolation/expansion with the final products release testing. We observed substantial decrease in cell number recovery after thawing and overnight culture. This observation might be explained by the high percentage of necrotic and apoptotic cells found just after thawing. Furthermore, we noticed fluctuations in percentage of CD4+CD25hiCD127- and CD4+FoxP3+ cells obtained from cryopreserved CD4+ as well as Treg cells. However, after re-stimulation Tregs expanded well, presented a stable phenotype and fulfilled the release criteria at the end of expansions. Cryopreservation of CD4+ cells for subsequent Treg isolation/expansion and cryopreservation of expanded Tregs with re-stimulation and expansion after thawing, are promising solutions to overcome detrimental effects of cryopreservation. Both of these cell-banking strategies for Treg therapy can be applied when designing new clinical trials. PMID:29515766

Cell banking for regulatory T cell-based therapy: strategies to overcome the impact of cryopreservation on the Treg viability and phenotype.

PubMed

Gołąb, Karolina; Grose, Randall; Placencia, Veronica; Wickrema, Amittha; Solomina, Julia; Tibudan, Martin; Konsur, Evelyn; Ciepły, Kamil; Marek-Trzonkowska, Natalia; Trzonkowski, Piotr; Millis, J Michael; Fung, John; Witkowski, Piotr

2018-02-09

The first clinical trials with adoptive Treg therapy have shown safety and potential efficacy. Feasibility of such therapy could be improved if cells are cryopreserved and stored until optimal timing for infusion. Herein, we report the evaluation of two cell-banking strategies for Treg therapy: 1) cryopreservation of CD4 + cells for subsequent Treg isolation/expansion and 2) cryopreservation of ex-vivo expanded Tregs (CD4 + CD25 hi CD127 lo/- cells). First, we checked how cryopreservation affects cell viability and Treg markers expression. Then, we performed Treg isolation/expansion with the final products release testing. We observed substantial decrease in cell number recovery after thawing and overnight culture. This observation might be explained by the high percentage of necrotic and apoptotic cells found just after thawing. Furthermore, we noticed fluctuations in percentage of CD4 + CD25 hi CD127 - and CD4 + FoxP3 + cells obtained from cryopreserved CD4 + as well as Treg cells. However, after re-stimulation Tregs expanded well, presented a stable phenotype and fulfilled the release criteria at the end of expansions. Cryopreservation of CD4 + cells for subsequent Treg isolation/expansion and cryopreservation of expanded Tregs with re-stimulation and expansion after thawing, are promising solutions to overcome detrimental effects of cryopreservation. Both of these cell-banking strategies for Treg therapy can be applied when designing new clinical trials.

Depletion of regulatory T cells leads to an exacerbation of delayed-type hypersensitivity arthritis in C57BL/6 mice that can be counteracted by IL-17 blockade

PubMed Central

Atkinson, Sara Marie; Hoffmann, Ute; Hamann, Alf; Bach, Emil; Danneskiold-Samsøe, Niels Banhos; Kristiansen, Karsten; Serikawa, Kyle; Fox, Brian; Kruse, Kim; Haase, Claus; Skov, Søren; Nansen, Anneline

2016-01-01

ABSTRACT Rodent models of arthritis have been extensively used in the elucidation of rheumatoid arthritis (RA) pathogenesis and are instrumental in the development of therapeutic strategies. Here we utilise delayed-type hypersensitivity arthritis (DTHA), a model in C57BL/6 mice affecting one paw with synchronised onset, 100% penetrance and low variation. We investigate the role of regulatory T cells (Tregs) in DTHA through selective depletion of Tregs and the role of IL-17 in connection with Treg depletion. Given the relevance of Tregs in RA, and the possibility of developing Treg-directed therapies, this approach could be relevant for advancing the understanding of Tregs in inflammatory arthritis. Selective depletion of Tregs was achieved using a Foxp3-DTR-eGFP mouse, which expresses the diphtheria toxin receptor (DTR) and enhanced green fluorescent protein (eGFP) under control of the Foxp3 gene. Anti-IL-17 monoclonal antibody (mAb) was used for IL-17 blockade. Numbers and activation of Tregs increased in the paw and its draining lymph node in DTHA, and depletion of Tregs resulted in exacerbation of disease as shown by increased paw swelling, increased infiltration of inflammatory cells, increased bone remodelling and increased production of inflammatory mediators, as well as increased production of anti-citrullinated protein antibodies. Anti-IL-17 mAb treatment demonstrated that IL-17 is important for disease severity in both the presence and absence of Tregs, and that IL-17 blockade is able to rescue mice from the exacerbated disease caused by Treg depletion and caused a reduction in RANKL, IL-6 and the number of neutrophils. We show that Tregs are important for the containment of inflammation and bone remodelling in DTHA. To our knowledge, this is the first study using the Foxp3-DTR-eGFP mouse on a C57BL/6 background for Treg depletion in an arthritis model, and we here demonstrate the usefulness of the approach to study the role of Tregs and IL-17 in arthritis. PMID:26822477

Induction of regulatory T cells: A role for probiotics and prebiotics to suppress autoimmunity.

PubMed

Dwivedi, Mitesh; Kumar, Prasant; Laddha, Naresh C; Kemp, E Helen

2016-04-01

Regulatory T cells (Tregs) are comprised of a heterogeneous population of cells that play a vital role in suppressing inflammation and maintaining immune tolerance. Given the crucial role of Tregs in maintaining immune homeostasis, it is probably not surprising that many microbial species and their metabolites have the potential to induce Tregs. There is now great interest in the therapeutic potential of probiotics and prebiotics based strategies for a range of autoimmune disorders. This review will summarise recent findings concerning the role of probiotics and prebiotics in induction of Tregs to ameliorate the autoimmune conditions. In addition, the article is focused to explain the different mechanisms of Treg induction and function by these probiotics and prebiotics, based on the available studies till date. The article further proposes that induction of Tregs by probiotics and prebiotics could lead to the development of new therapeutic approach towards curbing the autoimmune response and as an alternative to detrimental immunosuppressive drugs. Copyright © 2016 Elsevier B.V. All rights reserved.

Selective Expansion of Memory CD4+ T cells By Mitogenic Human CD28 Generates Inflammatory Cytokines and Regulatory T cells

PubMed Central

Singh, Manisha; Basu, Sreemanti; Camell, Christina; Couturier, Jacob; Nudelman, Rodolfo J.; Medina, Miguel A.; Rodgers, John R.; Lewis, Dorothy E.

2009-01-01

Co-stimulatory signals are important for development of effector and regulatory T cells. In this case, CD28 signaling is usually considered inert in the absence of signaling through the TCR. By contrast, mitogenic rat CD28 mAbs reportedly expand regulatory T cells without TCR stimulation. We found that a commercially available human CD28 mAb (ANC28) stimulated PBMCs without TCR co-ligation or cross-linking; ANC28 selectively expanded CD4+CD25+FoxP3−(T effector) and CD4+CD25+FoxP3+ (Treg) cells. ANC28 stimulated the CD45RO+ CD4+ (memory) population whereas CD45RA+CD4+ (naïve) cells did not respond. ANC28 also induced inflammatory cytokines. Treg induced by ANC28 retain the Treg phenotype longer than did co-stimulated Treg. Treg induced by ANC28 suppressed CD25− T cells through a contact-dependent mechanism. Purity influenced the response of CD4+CD25+ cells because bead-purified CD4+CD25+ cells (85–90% pure) responded strongly to ANC28, whereas 98% pure FACS-sorted CD4+CD25 bright (T-reg) did not respond. Purified CD4+CD25int cells responded similarly to the bead-purified CD4+CD25+ cells. Thus, pre-activated CD4+ T cells (CD25int) respond to ANC28 rather than Treg (CD25bright). The ability of ANC28 to expand both effectors producing inflammatory cytokines as well as suppressive regulatory T cells might be useful for ex vivo expansion of therapeutic T cells. PMID:18446791

Treating atherosclerosis with regulatory T cells.

PubMed

Foks, Amanda C; Lichtman, Andrew H; Kuiper, Johan

2015-02-01

Regulatory T cells (Tregs) play an important role in the regulation of T-cell-mediated immune responses through suppression of T-cell proliferation and secretion of inhibitory cytokines, such as interleukin-10 and transforming growth factor-β. Impaired Treg numbers and function have been associated with numerous diseases, and an imbalance between proinflammatory/proatherogenic cells and Tregs promotes atherosclerotic disease. Restoration of this balance by inducing Tregs has great therapeutic potential to prevent cardiovascular disease. In addition to suppressing differentiation and function of effector T cells, Tregs have been shown to induce anti-inflammatory macrophages, inhibit foam cell formation and to influence cholesterol metabolism. Furthermore, Tregs suppress immune responses of endothelial cells and innate lymphoid cells. In this review, we focus on the recent knowledge on Treg subsets, their activity and function in atherosclerosis, and discuss promising strategies to use Tregs as a therapeutic tool to prevent cardiovascular disease. © 2014 American Heart Association, Inc.

Expansion of Human Tregs from Cryopreserved Umbilical Cord Blood for GMP-Compliant Autologous Adoptive Cell Transfer Therapy.

PubMed

Seay, Howard R; Putnam, Amy L; Cserny, Judit; Posgai, Amanda L; Rosenau, Emma H; Wingard, John R; Girard, Kate F; Kraus, Morey; Lares, Angela P; Brown, Heather L; Brown, Katherine S; Balavage, Kristi T; Peters, Leeana D; Bushdorf, Ashley N; Atkinson, Mark A; Bluestone, Jeffrey A; Haller, Michael J; Brusko, Todd M

2017-03-17

Umbilical cord blood is a traditional and convenient source of cells for hematopoietic stem cell transplantation. Thymic regulatory T cells (Tregs) are also present in cord blood, and there is growing interest in the use of autologous Tregs to provide a low-risk, fully human leukocyte antigen (HLA)-matched cell product for treating autoimmune diseases, such as type 1 diabetes. Here, we describe a good manufacturing practice (GMP)-compatible Treg expansion protocol using fluorescence-activated cell sorting, resulting in a mean 2,092-fold expansion of Tregs over a 16-day culture for a median yield of 1.26 × 10 9 Tregs from single-donor cryopreserved units. The resulting Tregs passed prior clinical trial release criteria for Treg purity and sterility, including additional rigorous assessments of FOXP3 and Helios expression and epigenetic analysis of the FOXP3 Treg-specific demethylated region (TSDR). Compared with expanded adult peripheral blood Tregs, expanded cord blood Tregs remained more naive, as assessed by continued expression of CD45RA, produced reduced IFN-γ following activation, and effectively inhibited responder T cell proliferation. Immunosequencing of the T cell receptor revealed a remarkably diverse receptor repertoire within cord blood Tregs that was maintained following in vitro expansion. These data support the feasibility of generating GMP-compliant Tregs from cord blood for adoptive cell transfer therapies and highlight potential advantages in terms of safety, phenotypic stability, autoantigen specificity, and tissue distribution.

Phenotypic analysis of prostate-infiltrating lymphocytes reveals TH17 and Treg skewing.

PubMed

Sfanos, Karen Sandell; Bruno, Tullia C; Maris, Charles H; Xu, Lauren; Thoburn, Christopher J; DeMarzo, Angelo M; Meeker, Alan K; Isaacs, William B; Drake, Charles G

2008-06-01

Pathologic examination of prostate glands removed from patients with prostate cancer commonly reveals infiltrating CD4+ and CD8+ T cells. Little is known about the phenotype of these cells, despite accumulating evidence suggesting a potential role for chronic inflammation in the etiology of prostate cancer. We developed a technique that samples the majority of the peripheral prostate through serial needle aspirates. CD4+ prostate-infiltrating lymphocytes (PIL) were isolated using magnetic beads and analyzed for subset skewing using both flow cytometry and quantitative reverse transcription-PCR. The transcriptional profile of fluorescence-activated cell sorted prostate-infiltrating regulatory T cells (CD4+, CD25+, GITR+) was compared with naïve, peripheral blood T cells using microarray analysis. CD4+ PIL showed a paucity of TH2 (interleukin-4-secreting) cells, a surprising finding given the generally accepted association of these cells with chronic, smoldering inflammation. Instead, CD4+ PIL seemed to be skewed towards a regulatory Treg phenotype (FoxP3+) as well as towards the TH17 phenotype (interleukin-17+). We also found that a preponderance of TH17-mediated inflammation was associated with a lower pathologic Gleason score. These protein level data were reflected at the message level, as analyzed by quantitative reverse transcription-PCR. Microarray analysis of pooled prostate-infiltrating T(reg) revealed expected Treg-associated transcripts (FoxP3, CTLA-4, GITR, LAG-3) as well as a number of unique cell surface markers that may serve as additional Treg markers. Taken together, these data suggest that TH17 and/or Treg CD4+ T cells (rather than TH2 T cells) may be involved in the development or progression of prostate cancer.

Phenotypic Analysis of Prostate-Infiltrating Lymphocytes Reveals TH17 and Treg Skewing

PubMed Central

Sfanos, Karen Sandell; Bruno, Tullia C.; Maris, Charles H.; Xu, Lauren; Thoburn, Christopher J.; DeMarzo, Angelo M.; Meeker, Alan K.; Isaacs, William B.; Drake, Charles G.

2011-01-01

Purpose Pathologic examination of prostate glands removed from patients with prostate cancer commonly reveals infiltrating CD4+ and CD8+ T cells. Little is known about the phenotype of these cells, despite accumulating evidence suggesting a potential role for chronic inflammation in the etiology of prostate cancer. Experimental Design We developed a technique that samples the majority of the peripheral prostate through serial needle aspirates. CD4+ prostate-infiltrating lymphocytes (PIL) were isolated using magnetic beads and analyzed for subset skewing using both flow cytometry and quantitative reverse transcription-PCR. The transcriptional profile of fluorescence-activated cell sorted prostate-infiltrating regulatory T cells (CD4+, CD25+, GITR+) was compared with naïve, peripheral blood T cells using microarray analysis. Results CD4+ PIL showed a paucity of TH2 (interleukin-4– secreting) cells, a surprising finding given the generally accepted association of these cells with chronic, smoldering inflammation. Instead, CD4+ PIL seemed to be skewed towards a regulatory Treg phenotype (FoxP3+) as well as towards the TH17 phenotype (interleukin-17+). We also found that a preponderance of TH17-mediated inflammation was associated with a lower pathologic Gleason score. These protein level data were reflected at the message level, as analyzed by quantitative reverse transcription-PCR. Microarray analysis of pooled prostate-infiltrating Treg revealed expected Treg-associated transcripts (FoxP3, CTLA-4, GITR, LAG-3) as well as a number of unique cell surface markers that may serve as additional Treg markers. Conclusion Taken together, these data suggest that TH17 and/or Treg CD4+ T cells (rather than TH2 T cells) may be involved in the development or progression of prostate cancer. PMID:18519750

Components of Streptococcus pneumoniae suppress allergic airways disease and NKT cells by inducing regulatory T cells.

PubMed

Thorburn, Alison N; Foster, Paul S; Gibson, Peter G; Hansbro, Philip M

2012-05-01

Asthma is an allergic airways disease (AAD) caused by dysregulated immune responses and characterized by eosinophilic inflammation, mucus hypersecretion, and airway hyperresponsiveness (AHR). NKT cells have been shown to contribute to AHR in some mouse models. Conversely, regulatory T cells (Tregs) control aberrant immune responses and maintain homeostasis. Recent evidence suggests that Streptococcus pneumoniae induces Tregs that have potential to be harnessed therapeutically for asthma. In this study, mouse models of AAD were used to identify the S. pneumoniae components that have suppressive properties, and the mechanisms underlying suppression were investigated. We tested the suppressive capacity of type-3-polysaccharide (T3P), isolated cell walls, pneumolysoid (Ply) and CpG. When coadministered, T3P + Ply suppressed the development of: eosinophilic inflammation, Th2 cytokine release, mucus hypersecretion, and AHR. Importantly, T3P + Ply also attenuated features of AAD when administered during established disease. We show that NKT cells contributed to the development of AAD and also were suppressed by T3P + Ply treatment. Furthermore, adoptive transfer of NKT cells induced AHR, which also could be reversed by T3P + Ply. T3P + Ply-induced Tregs were essential for the suppression of NKT cells and AAD, which was demonstrated by Treg depletion. Collectively, our results show that the S. pneumoniae components T3P + Ply suppress AAD through the induction of Tregs that blocked the activity of NKT cells. These data suggest that S. pneumoniae components may have potential as a therapeutic strategy for the suppression of allergic asthma through the induction of Tregs and suppression of NKT cells.

Decline of FoxP3+ Regulatory CD4 T Cells in Peripheral Blood of Children Heavily Exposed to Malaria

PubMed Central

Boyle, Michelle J.; Jagannathan, Prasanna; Farrington, Lila A.; Eccles-James, Ijeoma; Wamala, Samuel; McIntyre, Tara I; Vance, Hilary M.; Bowen, Katherine; Nankya, Felistas; Auma, Ann; Nalubega, Mayimuna; Sikyomu, Esther; Naluwu, Kate; Rek, John; Katureebe, Agaba; Bigira, Victor; Kapisi, James; Tappero, Jordan; Muhindo, Mary K; Greenhouse, Bryan; Arinaitwe, Emmanuel; Dorsey, Grant; Kamya, Moses R.; Feeney, Margaret E.

2015-01-01

FoxP3+ regulatory CD4 T cells (Tregs) help to maintain the delicate balance between pathogen-specific immunity and immune-mediated pathology. Prior studies suggest that Tregs are induced by P. falciparum both in vivo and in vitro; however, the factors influencing Treg homeostasis during acute and chronic infections, and their role in malaria immunopathogenesis, remain unclear. We assessed the frequency and phenotype of Tregs in well-characterized cohorts of children residing in a region of high malaria endemicity in Uganda. We found that both the frequency and absolute numbers of FoxP3+ Tregs in peripheral blood declined markedly with increasing prior malaria incidence. Longitudinal measurements confirmed that this decline occurred only among highly malaria-exposed children. The decline of Tregs from peripheral blood was accompanied by reduced in vitro induction of Tregs by parasite antigen and decreased expression of TNFR2 on Tregs among children who had intense prior exposure to malaria. While Treg frequencies were not associated with protection from malaria, there was a trend toward reduced risk of symptomatic malaria once infected with P. falciparum among children with lower Treg frequencies. These data demonstrate that chronic malaria exposure results in altered Treg homeostasis, which may impact the development of antimalarial immunity in naturally exposed populations. PMID:26182204

Frequency of CD4+CD25+Foxp3+ cells in peripheral blood in relation to urinary bladder cancer malignancy indicators before and after surgical removal.

PubMed

Jóźwicki, Wojciech; Brożyna, Anna A; Siekiera, Jerzy; Slominski, Andrzej T

2016-03-08

Tumor cells communicate with stromal cells, including cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs), to form microenvironment inhibiting immune responses. Regulatory T cells (Tregs, CD4+CD25+FoxP3+) stimulate immune tolerance and facilitate tumor progression. We analyzed the changes in Treg frequencies assessed using flow cytometry in the peripheral blood of patients with urothelial bladder cancer before and after tumor-removal. Changes in Treg frequency were investigated in relation to clinicopathomorphological indicators of tumor malignancy and expression of RCAS1 on CAFs and TAMs. Higher Treg frequencies were observed in early phase of tumor growth (pTa-pT2), in larger tumors, with more aggressive type of invasion, and with expression of RCAS1. The later phase of tumor development, accompanied by a nonclassic differentiations and pT3-pT4 advancement, had lower number of tumor infiltrating lymphocytes (TILs) and lower Treg frequency. Furthermore, in pT2-pT4 tumors, a decreased post-surgery Treg frequency was associated with poorer prognosis: patients with the lowest frequency of Tregs died first. These findings strongly suggest that the Treg frequencies at later phase of tumor growth, associated with a low anti-tumor response, represent a new and important prognostic indicator in urinary bladder cancer.

Separation of human CD4+CD39+ T cells by magnetic beads reveals two phenotypically and functionally different subsets

PubMed Central

Schuler, Patrick J.; Harasymczuk, Malgorzata; Schilling, Bastian; Lang, Stephan; Whiteside, Theresa L.

2011-01-01

Objective The ectonucleotidase CD39 is an enzyme involved in adenosine production. Its surface expression on human regulatory T cells (Treg) allows for their flow-cytometry-based isolation from peripheral blood. To further develop and improve this method on a scale supporting translational studies, we introduced capture of CD39+ Treg on magnetic immunobeads. Methods Peripheral blood mononuclear cells (PBMC) obtained from healthy donors were used for negative selection of CD4+ T cells on AutoMACS using antibodies (Abs) specific for all lineage+ cells. CD4+CD39+ Treg were captured by biotin-conjugated anti-CD39 Abs and anti-biotin Ab-coated magnetic beads. Isolated CD4+CD39+ T cells were phenotyped by flow cytometry for Treg-associated markers: CD39, CD73, FOXP3, CD25, CTLA-4, CCR4, CD45RO and CD121a or for the absence of CD127 and CD49d. CFSE-based proliferation assays and ATP hydrolysis were used to measure Treg functions. Results The purity, recovery and viability of the separated CD4+CD39+ T cells were satisfactory. The isolated CD4+CD39+ T cell population consisted of FOXP3+CD25+ T cells which hydrolyzed exogenous ATP and suppressed autologous CD4+ T cell proliferation and of FOXP3negCD25neg T cells without suppressor function. The same two subsets were detectable by flow cytometry in normal PBMC, gating on CD4+CD39+, CD4+CD127neg, CD4+CD49dneg or CD4+CD25high Treg. Conclusion CD4+CD39+ Treg capture on immunobeads led to a discovery of two CD39+ subsets. Similar to CD39+ Treg in the peripheral blood, half of these cells are CD25+FOXP3+ active suppressor cells, while the other half are CD25negFOXP3neg and do not mediate suppression. PMID:21513715

Age-dependent divergent effects of OX40L treatment on the development of diabetes in NOD mice

PubMed Central

Haddad, Christine S.; Bhattacharya, Palash; Alharshawi, Khaled; Marinelarena, Alejandra; Kumar, Prabhakaran; El-Sayed, Osama; Elshabrawy, Hatem A.; Epstein, Alan L.; Prabhakar, Bellur S.

2016-01-01

Earlier, we have shown that GM-CSF derived bone marrow dendritic cells (G-BMDCs) can expand Foxp3+ regulatory T-cells (Tregs) through a TCR-independent, but IL-2 dependent mechanism that required OX40L/OX40 interaction. While some reports have shown suppression of autoimmunity upon treatment with an OX40 agonist, others have shown exacerbation of autoimmune disease instead. To better understand the basis for these differing outcomes, we compared the effects of OX40L treatment in 6-week-old pre-diabetic and 12-week-old near diabetic NOD mice. Upon treatment with OX40L, 6-week-old NOD mice remained normoglycemic and showed a significant increase in Tregs in their spleen and lymph nodes, while 12-week-old NOD mice very rapidly developed hyperglycemia and failed to show Treg increase in spleen or LN. Interestingly, OX40L treatment increased Tregs in the thymus of both age groups. However, it induced Foxp3+CD103+CD38− stable-phenotype Tregs in the thymus and reduced the frequency of autoreactive Teff cells in 6-week-old mice; while it induced Foxp3+CD103−CD38+ labile-phenotype Tregs in the thymus and increased autoreactive CD4+ T cells in the periphery of 12-week-old mice. This increase in autoreactive CD4+ T cells was likely due to either a poor suppressive function or conversion of labile Tregs into Teff cells. Using ex vivo cultures, we found that the reduction in Treg numbers in 12-week-old mice was likely due to IL-2 deficit, and their numbers could be increased upon addition of exogenous IL-2. The observed divergent effects of OX40L treatment were likely due to differences in the ability of 6- and 12-week-old NOD mice to produce IL-2. PMID:27245356

Production of IL-10 by CD4+ regulatory T cells during the resolution of infection promotes the maturation of memory CD8+ T cells

PubMed Central

Laidlaw, Brian J; Cui, Weiguo; Amezquita, Robert A; Gray, Simon M; Guan, Tianxia; Lu, Yisi; Kobayashi, Yasushi; Flavell, Richard A; Kleinstein, Steven H; Craft, Joe; Kaech, Susan M

2016-01-01

Memory CD8+ T cells are critical for host defense upon reexposure to intracellular pathogens. We found that interleukin 10 (IL-10) derived from CD4+ regulatory T cells (Treg cells) was necessary for the maturation of memory CD8+ T cells following acute infection with lymphocytic choriomeningitis virus (LCMV). Treg cell–derived IL-10 was most important during the resolution phase, calming inflammation and the activation state of dendritic cells. Adoptive transfer of IL-10-sufficient Treg cells during the resolution phase ‘restored’ the maturation of memory CD8+ T cells in IL-10-deficient mice. Our data indicate that Treg cell–derived IL-10 is needed to insulate CD8+ T cells from inflammatory signals, and reveal that the resolution phase of infection is a critical period that influences the quality and function of developing memory CD8+ T cells. PMID:26147684

T cell subsets in cord blood are influenced by maternal allergy and associated with atopic dermatitis.

PubMed

Fu, Yujing; Lou, Hongfei; Wang, Chengshuo; Lou, Wei; Wang, Yang; Zheng, Tao; Zhang, Luo

2013-03-01

This study aimed to investigate the influence of maternal allergy on cord blood regulatory and effector T cells and to evaluate their role as a predictor of atopic dermatitis (AD) during the first 2 yr of life. Seventy mother-infant pairs were recruited in this prospective birth cohort study (21 allergic and 49 non-allergic mothers). Cord blood samples were collected and assayed for the percentage of regulatory T cells (Treg), interferon-γ (IFN-γ), and interleukin-4 (IL-4) producing T cells (Th1 and Th2, respectively) using flow cytometry. Experiments were undertaken to assess the function of cord blood CD4(+) CD25(+) CD127(-) Treg cells by cell proliferation and cytokine responses. Their offspring at the age of 2 yr old were evaluated by dermatologists to determine whether they had AD. During the first 2 yr of life, 15.7% of the children developed a physician-diagnosed AD. A significantly increased percentage of Th2 cell was observed in cord blood of newborns with maternal allergy. Treg/Th2 ratio significantly decreased among the offspring of allergic mothers. Treg cell-associated suppression of Th2 response was attenuated in Der p1-stimulated CD4(+) CD25(-) T cells from the offspring of allergic mothers. Children with reduced Th1/Th2 (p = 0.001, OR = 0.37) and Treg/Th2 (p = 0.001, OR = 0.47) ratio in cord blood had a higher risk of developing AD. Maternal allergic status is associated with increased percentage of IL-4(+) CD4(+) T cells and a reduced Treg/Th2 ratio in cord blood at their children's birth, which may predispose to an increased risk for developing AD. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Targeting IL-2: an unexpected effect in treating immunological diseases.

PubMed

Ye, Congxiu; Brand, David; Zheng, Song G

2018-01-01

Regulatory T cells (Treg) play a crucial role in maintaining immune homeostasis since Treg dysfunction in both animals and humans is associated with multi-organ autoimmune and inflammatory disease. While IL-2 is generally considered to promote T-cell proliferation and enhance effector T-cell function, recent studies have demonstrated that treatments that utilize low-dose IL-2 unexpectedly induce immune tolerance and promote Treg development resulting in the suppression of unwanted immune responses and eventually leading to treatment of some autoimmune disorders. In the present review, we discuss the biology of IL-2 and its signaling to help define the key role played by IL-2 in the development and function of Treg cells. We also summarize proof-of-concept clinical trials which have shown that low-dose IL-2 can control autoimmune diseases safely and effectively by specifically expanding and activating Treg. However, future studies will be needed to validate a better and safer dosing strategy for low-dose IL-2 treatments utilizing well-controlled clinical trials. More studies will also be needed to validate the appropriate dose of IL-2/anti-cytokine or IL-2/anti-IL-2 complex in the experimental animal models before moving to the clinic.

Corruption of dendritic cell antigen presentation during acute GVHD leads to regulatory T-cell failure and chronic GVHD

PubMed Central

Leveque-El mouttie, Lucie; Koyama, Motoko; Le Texier, Laetitia; Markey, Kate A.; Cheong, Melody; Kuns, Rachel D.; Lineburg, Katie E.; Teal, Bianca E.; Alexander, Kylie A.; Clouston, Andrew D.; Blazar, Bruce R.; Hill, Geoffrey R.

2016-01-01

Chronic graft-versus-host disease (cGVHD) is a major cause of late mortality following allogeneic bone marrow transplantation (BMT) and is characterized by tissue fibrosis manifesting as scleroderma and bronchiolitis obliterans. The development of acute GVHD (aGVHD) is a powerful clinical predictor of subsequent cGVHD, suggesting that aGVHD may invoke the immunologic pathways responsible for cGVHD. In preclinical models in which sclerodermatous cGVHD develops after a preceding period of mild aGVHD, we show that antigen presentation within major histocompatibility complex (MHC) class II of donor dendritic cells (DCs) is markedly impaired early after BMT. This is associated with a failure of regulatory T-cell (Treg) homeostasis and cGVHD. Donor DC-restricted deletion of MHC class II phenocopied this Treg deficiency and cGVHD. Moreover, specific depletion of donor Tregs after BMT also induced cGVHD, whereas adoptive transfer of Tregs ameliorated it. These data demonstrate that the defect in Treg homeostasis seen in cGVHD is a causative lesion and is downstream of defective antigen presentation within MHC class II that is induced by aGVHD. PMID:27338097

Corruption of dendritic cell antigen presentation during acute GVHD leads to regulatory T-cell failure and chronic GVHD.

PubMed

Leveque-El Mouttie, Lucie; Koyama, Motoko; Le Texier, Laetitia; Markey, Kate A; Cheong, Melody; Kuns, Rachel D; Lineburg, Katie E; Teal, Bianca E; Alexander, Kylie A; Clouston, Andrew D; Blazar, Bruce R; Hill, Geoffrey R; MacDonald, Kelli P A

2016-08-11

Chronic graft-versus-host disease (cGVHD) is a major cause of late mortality following allogeneic bone marrow transplantation (BMT) and is characterized by tissue fibrosis manifesting as scleroderma and bronchiolitis obliterans. The development of acute GVHD (aGVHD) is a powerful clinical predictor of subsequent cGVHD, suggesting that aGVHD may invoke the immunologic pathways responsible for cGVHD. In preclinical models in which sclerodermatous cGVHD develops after a preceding period of mild aGVHD, we show that antigen presentation within major histocompatibility complex (MHC) class II of donor dendritic cells (DCs) is markedly impaired early after BMT. This is associated with a failure of regulatory T-cell (Treg) homeostasis and cGVHD. Donor DC-restricted deletion of MHC class II phenocopied this Treg deficiency and cGVHD. Moreover, specific depletion of donor Tregs after BMT also induced cGVHD, whereas adoptive transfer of Tregs ameliorated it. These data demonstrate that the defect in Treg homeostasis seen in cGVHD is a causative lesion and is downstream of defective antigen presentation within MHC class II that is induced by aGVHD. © 2016 by The American Society of Hematology.

IL-17+ regulatory T cells in the microenvironments of chronic inflammation and cancer.

PubMed

Kryczek, Ilona; Wu, Ke; Zhao, Ende; Wei, Shuang; Vatan, Linhua; Szeliga, Wojciech; Huang, Emina; Greenson, Joel; Chang, Alfred; Roliński, Jacek; Radwan, Piotr; Fang, Jingyuan; Wang, Guobin; Zou, Weiping

2011-04-01

Foxp3(+)CD4(+) regulatory T (Treg) cells inhibit immune responses and temper inflammation. IL-17(+)CD4(+) T (Th17) cells mediate inflammation of autoimmune diseases. A small population of IL-17(+)Foxp3(+)CD4(+) T cells has been observed in peripheral blood in healthy human beings. However, the biology of IL-17(+)Foxp3(+)CD4(+) T cells remains poorly understood in humans. We investigated their phenotype, cytokine profile, generation, and pathological relevance in patients with ulcerative colitis. We observed that high levels of IL-17(+)Foxp3(+)CD4(+) T cells were selectively accumulated in the colitic microenvironment and associated colon carcinoma. The phenotype and cytokine profile of IL-17(+)Foxp3(+)CD4(+) T cells was overlapping with Th17 and Treg cells. Myeloid APCs, IL-2, and TGF-β are essential for their induction from memory CCR6(+) T cells or Treg cells. IL-17(+)Foxp3(+)CD4(+) T cells functionally suppressed T cell activation and stimulated inflammatory cytokine production in the colitic tissues. Our data indicate that IL-17(+)Foxp3(+) cells may be "inflammatory" Treg cells in the pathological microenvironments. These cells may contribute to the pathogenesis of ulcerative colitis through inducing inflammatory cytokines and inhibiting local T cell immunity, and in turn may mechanistically link human chronic inflammation to tumor development. Our data therefore challenge commonly held beliefs of the anti-inflammatory role of Treg cells and suggest a more complex Treg cell biology, at least in the context of human chronic inflammation and associated carcinoma.

Increase in activated Treg in TIL in lung cancer and in vitro depletion of Treg by ADCC using an antihuman CCR4 mAb (KM2760).

PubMed

Kurose, Koji; Ohue, Yoshihiro; Sato, Eiichi; Yamauchi, Akira; Eikawa, Shingo; Isobe, Midori; Nishio, Yumi; Uenaka, Akiko; Oka, Mikio; Nakayama, Eiichi

2015-01-01

Tregs infiltrate tumors and inhibit immune responses against them. We investigated subpopulations of Foxp3 CD4 T cells previously defined by Miyara et al. (Immunity 30, 899-911, 2009) in peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TILs) in lung cancer. We also showed that Tregs in healthy donors that express CCR4 could be efficiently eliminated in vitro by cotreatment with antihuman (h) CCR4 mAb (KM2760) and NK cells. In lung cancer, the number of activated/effector Tregs and non-Tregs, but not resting/naive Tregs, was increased in TILs compared with the number of those cells in PBMCs. The non-Treg population contained Th2 and Th17. CCR4 expression on activated/effector Tregs and non-Tregs in TILs was down-regulated compared with that on those cells in PBMCs. Chemokinetic migration of CD25 CD4 T cells containing the Treg population sorted from the PBMCs of healthy donors to CCL22/MDC was abrogated by pretreatment with anti-hCCR4 mAb (KM2760). The inhibitory activity of CD25 CD127 CD4 Tregs on the proliferative response of CD4 and CD8 T cells stimulated with anti-CD3/CD28 coated beads was abrogated by adding an anti-hCCR4 mAb (KM2760) and CD56 NK cells to the culture. The findings suggested the CCR4 on activated/effector Tregs and non-Tregs was functionally involved in the chemokinetic migration and accumulation of those cells to the tumor site. In vitro findings of efficient elimination of Tregs may give the basis for implementation of a clinical trial to investigate Treg depletion by administration of an anti-hCCR4 mAb to solid cancer patients.

CRISPR and personalized Treg therapy: new insights into the treatment of rheumatoid arthritis.

PubMed

Safari, Fatemeh; Farajnia, Safar; Arya, Maryam; Zarredar, Habib; Nasrolahi, Ava

2018-06-01

Rheumatoid arthritis (RA), as one of the most disabling autoimmune diseases, is a common health problem that progressively reduces the life quality of patients. Although various biologics have been introduced for RA, attempts to establish an efficient long-term therapies failed due to the heterogeneity of this disease. In the last decade, immunomodulatory approaches such as T cell adoptive therapy have been developed for controlling autoimmunity. Regulatory T cells (Tregs), the major self-tolerance mediator, are crucial for down-regulation of aberrant immune stimulations. Hence, recruiting ex vivo Tregs emerged as a promising therapy for a variety of autoimmune diseases. The major bottleneck of the Treg adoptive therapy is maintaining the in vivo stability and plasticity of these fascinating cells. Recent progress in genome editing technology clustered regularly interspaced short palindromic repeats (CRISPR) in combination with CRISPR-associated (Cas) 9 system provided a new solution for this bottleneck. The present paper discusses RA pathogenesis and the potential application of new developments in CRISPR-mediated Treg genome editing in personalized therapy of RA.

Regulatory T cells control HIV replication in activated T cells through a cAMP-dependent mechanism

PubMed Central

Moreno-Fernandez, Maria E.; Rueda, Cesar Mauricio; Rusie, Laura K.

2011-01-01

We hypothesized that regulatory T cells (Tregs) could play a beneficial role during HIV infection by controlling HIV replication in conventional T cells (Tcons). Purified Tregs and Tcons from healthy donors were activated separately. Tcons were infected with the X4 or R5 HIV strains and cultured with or without autologous Tregs. Coculture of Tcons and Tregs resulted in a dose-dependent inhibition of Tcon infection, which was significant when a 1:1 Treg:Tcon ratio was used. Treg suppression of HIV infection was largely mediated by contact-dependent mechanisms. Blockage of cytotoxic T-lymphocyte–associated antigen-4 did not significantly reduce Treg function. In contrast, Tregs acted through cAMP-dependent mechanisms, because the decrease of cAMP levels in Tregs, the blockade of gap junction formation between Tregs and Tcons, the blockage of CD39 activity, and the blockage of protein kinase A in Tcons all abolished Treg-mediated suppression of HIV replication. Our data suggest a complex role for Tregs during HIV infection. Although Tregs inhibit specific immune responses, their inhibition of HIV replication in Tcons may play a beneficial role, particularly during early HIV infection, when the effector immune cells are not yet activated. Such a protective role of Tregs could have a profound impact on infection outcome. PMID:21436067

Regulatory T cells may participate in Helicobacter pylori persistence in gastric MALT lymphoma: lessons from an animal model.

PubMed

Laur, Amandine Marine; Floch, Pauline; Chambonnier, Lucie; Benejat, Lucie; Korolik, Victoria; Giese, Alban; Dubus, Pierre; Mégraud, Francis; Bandeira, Antonio; Lehours, Philippe

2016-01-19

It has been postulated that the emergence of autoimmune gastritis in neonatal thymectomised (d3Tx) BALB/c mice may be a consequence of post-surgery deficit in Tregs. In this study, previously obtained samples from d3Tx mice were used in order to determine whether thymectomy creates a deficit in this T cell subset thereby allowing the emergence of autoimmune phenomena as a prerequisite for GML. The splenic Treg reserve and the local recruitment of these cells in the gastric mucosa were investigated using complementary molecular and immunohistochemistry approaches. Higher Foxp3/CD3 ratios were found in the spleen of non-infected d3Tx mice compared to non-thymectomised (NTx) controls. These results indicate a relative enrichment of Tregs following thymectomy in adult mice. The absence of Treg depletion in d3Tx mice is in line with the absence of auto-immune gastritis in non-infected d3Tx mice. Higher levels of T cell and Treg infiltration were also found in the stomach of GML-developing d3Tx mice versus NTx mice. Surprisingly, inflammatory scores inversely correlated with the bacterial inoculum. The presence of a small Treg containing compartment among gastric biopsies of GML developing d3Tx mice may play a role in perseverance of a minimal bacterial numbers thereby maintaining an antigen-dependent stimulation and proliferation.

Adoptive regulatory T cell therapy: challenges in clinical transplantation.

PubMed

Safinia, Niloufar; Sagoo, Pervinder; Lechler, Robert; Lombardi, Giovanna

2010-08-01

The identification and characterisation of regulatory T cells (Tregs) has recently opened up exciting opportunities for Treg cell therapy in transplantation. In this review, we outline the basic biology of Tregs and discuss recent advances and challenges for the identification, isolation and expansion of these cells for cell therapy. Tregs of thymic origin have been shown to be key regulators of immune responses in mice and humans, preventing autoimmunity, graft-versus-host disease and organ graft rejection in the transplantation setting. To date, a variety of different methods to isolate and expand Tregs ex vivo have been advocated. Although promising, relatively few clinical trials of human Treg cell infusion have been initiated. Many key questions about Treg cell therapy still remain and here we provide an in-depth analysis and highlight the challenges and opportunities for immune intervention with Treg-based therapeutics in clinical transplantation.

How Numbers, Nature, and Immune Status of Foxp3+ Regulatory T-Cells Shape the Early Immunological Events in Tumor Development

PubMed Central

Darrasse-Jèze, Guillaume; Podsypanina, Katrina

2013-01-01

The influence of CD4+CD25+Foxp3+ regulatory T-cells (Tregs) on cancer progression has been demonstrated in a large number of preclinical models and confirmed in several types of malignancies. Neoplastic processes trigger an increase of Treg numbers in draining lymph nodes, spleen, blood, and tumors, leading to the suppression of anti-tumor responses. Treg-depletion before or early in tumor development may lead to complete tumor eradication and extends survival of mice and humans. However this strategy is ineffective in established tumors, highlighting the critical role of the early Treg-tumor encounters. In this review, after discussing old and new concepts of immunological tumor tolerance, we focus on the nature (thymus-derived vs. peripherally derived) and status (naïve or activated/memory) of the regulatory T-cells at tumor emergence. The recent discoveries in this field suggest that the activation status of Tregs and effector T-cells (Teffs) at the first encounter with the tumor are essential to shape the fate and speed of the immune response across a variety of tumor models. The relative timing of activation/recruitment of anti-tumor cells vs. tolerogenic cells at tumor emergence appears to be crucial in the identification of tumor cells as friend or foe, which has broad implications for the design of cancer immunotherapies. PMID:24133490

Inhibition of phosphoantigen-mediated gammadelta T-cell proliferation by CD4+ CD25+ FoxP3+ regulatory T cells.

PubMed

Kunzmann, Volker; Kimmel, Brigitte; Herrmann, Thomas; Einsele, Hermann; Wilhelm, Martin

2009-02-01

Tumour growth promotes the expansion of CD4(+) CD25(+) FoxP3(+) regulatory T cells (Tregs) which suppress various arms of immune responses and might therefore contribute to tumour immunosurveillance. In this study, we found an inverse correlation between circulating Treg frequencies and phosphoantigen-induced gammadelta T-cell proliferation in cancer patients, which prompted us to address the role of Tregs in controlling the gammadelta T-cell arm of innate immune responses. In vitro, human Treg-peripheral blood mononuclear cell (PBMC) co-cultures strongly inhibited phosphoantigen-induced proliferation of gammadelta T cells and depletion of Tregs restored the impaired phosphoantigen-induced gammadelta T-cell proliferation of cancer patients. Tregs did not suppress other effector functions of gammadelta T cells such as cytokine production or cytotoxicity. Our experiments indicate that Tregs do not mediate their suppressive activity via a cell-cell contact-dependent mechanism, but rather secrete a soluble non-proteinaceous factor, which is independent of known soluble factors interacting with amino acid depletion (e.g. arginase-diminished arginine and indolamine 2,3-dioxygenase-diminished tryptophan) or nitric oxide (NO) production. However, the proliferative activity of alphabeta T cells was not affected by this cell-cell contact-independent suppressive activity induced by Tregs. In conclusion, these findings indicate a potential new mechanism by which Tregs can specifically suppress gammadelta T cells and highlight the strategy of combining Treg inhibition with subsequent gammadelta T-cell activation to enhance gammadelta T cell-mediated immunotherapy.

CD4+CD25+ regulatory T cells suppress mast cell degranulation and allergic responses through OX40-OX40L interaction.

PubMed

Gri, Giorgia; Piconese, Silvia; Frossi, Barbara; Manfroi, Vanessa; Merluzzi, Sonia; Tripodo, Claudio; Viola, Antonella; Odom, Sandra; Rivera, Juan; Colombo, Mario P; Pucillo, Carlo E

2008-11-14

T regulatory (Treg) cells play a role in the suppression of immune responses, thus serving to induce tolerance and control autoimmunity. Here, we explored whether Treg cells influence the immediate hypersensitivity response of mast cells (MCs). Treg cells directly inhibited the FcvarepsilonRI-dependent MC degranulation through cell-cell contact involving OX40-OX40L interactions between Treg cells and MCs, respectively. When activated in the presence of Treg cells, MCs showed increased cyclic adenosine monophosphate (cAMP) concentrations and reduced Ca(2+) influx, independently of phospholipase C (PLC)-gamma2 or Ca(2+) release from intracellular stores. Antagonism of cAMP in MCs reversed the inhibitory effects of Treg cells, restoring normal Ca(2+) responses and degranulation. Importantly, the in vivo depletion or inactivation of Treg cells caused enhancement of the anaphylactic response. The demonstrated crosstalk between Treg cells and MCs defines a previously unrecognized mechanism controlling MC degranulation. Loss of this interaction may contribute to the severity of allergic responses.

Expansion of CD25-Negative Forkhead Box P3-Positive T Cells during HIV and Mycobacterium tuberculosis Infection.

PubMed

Angerami, Matías T; Suarez, Guadalupe V; Vecchione, María B; Laufer, Natalia; Ameri, Diego; Ben, Graciela; Perez, Hector; Sued, Omar; Salomón, Horacio; Quiroga, María F

2017-01-01

Tuberculosis (TB) and HIV alter the immune system, and coinfected (HIV-TB) individuals usually present deregulations of T-lymphocytic immune response. We previously observed an increased frequency of "unconventional" CD4 + CD25 - FoxP3 + Treg (uTreg) population during HIV-TB disease. Therefore, we aimed to explore the phenotype and function of uTreg and conventional CD4 + CD25 + FoxP3 + Treg subsets (cTreg) in this context. We evaluated the expression of CD39, programmed cell death protein 1 (PD1), glucocorticoid-induced tumor necrosis factor receptor (GITR), and the effector/memory distribution by flow cytometry in cTreg and uTreg. Also, IL-10, TGF-β, IFN-γ production, and the suppressor capacity of uTregs were analyzed in cocultures with effector lymphocytes and compared with the effect of regulatory T cells (Tregs). We found diminished expression of CD39 and higher levels of PD1 on uTreg compared to cTreg in both HIV-TB and healthy donors (HD). In addition, uTreg and cTreg showed differences in maturation status in both HIV-TB and HD groups, due to the expansion of effector memory uTregs. Interestingly, both HIV-TB and HD showed a pronounced production of IFN-γ in uTreg population, though no significant differences were observed for IL-10 and TGF-β production between uTreg and cTreg. Moreover, IFN-γ + cells were restricted to the CD39 - uTreg population. Finally, when the suppressor capacity was evaluated, both uTreg and cTreg inhibited polyclonal T cell-proliferation and IFN-γ production in a similar extent. These findings suggest that uTregs, which are expanded during HIV-TB coinfection, exert regulatory functions in a similar way to cTregs despite an altered surface expression of Treg characteristic markers and differences in cytokine production.

Expansion of CD25-Negative Forkhead Box P3-Positive T Cells during HIV and Mycobacterium tuberculosis Infection

PubMed Central

Angerami, Matías T.; Suarez, Guadalupe V.; Vecchione, María B.; Laufer, Natalia; Ameri, Diego; Ben, Graciela; Perez, Hector; Sued, Omar; Salomón, Horacio; Quiroga, María F.

2017-01-01

Tuberculosis (TB) and HIV alter the immune system, and coinfected (HIV-TB) individuals usually present deregulations of T-lymphocytic immune response. We previously observed an increased frequency of “unconventional” CD4+CD25−FoxP3+ Treg (uTreg) population during HIV-TB disease. Therefore, we aimed to explore the phenotype and function of uTreg and conventional CD4+CD25+FoxP3+ Treg subsets (cTreg) in this context. We evaluated the expression of CD39, programmed cell death protein 1 (PD1), glucocorticoid-induced tumor necrosis factor receptor (GITR), and the effector/memory distribution by flow cytometry in cTreg and uTreg. Also, IL-10, TGF-β, IFN-γ production, and the suppressor capacity of uTregs were analyzed in cocultures with effector lymphocytes and compared with the effect of regulatory T cells (Tregs). We found diminished expression of CD39 and higher levels of PD1 on uTreg compared to cTreg in both HIV-TB and healthy donors (HD). In addition, uTreg and cTreg showed differences in maturation status in both HIV-TB and HD groups, due to the expansion of effector memory uTregs. Interestingly, both HIV-TB and HD showed a pronounced production of IFN-γ in uTreg population, though no significant differences were observed for IL-10 and TGF-β production between uTreg and cTreg. Moreover, IFN-γ+ cells were restricted to the CD39− uTreg population. Finally, when the suppressor capacity was evaluated, both uTreg and cTreg inhibited polyclonal T cell-proliferation and IFN-γ production in a similar extent. These findings suggest that uTregs, which are expanded during HIV-TB coinfection, exert regulatory functions in a similar way to cTregs despite an altered surface expression of Treg characteristic markers and differences in cytokine production. PMID:28536578

Targeting CXCR4 reverts the suppressive activity of T-regulatory cells in renal cancer.

PubMed

Santagata, Sara; Napolitano, Maria; D'Alterio, Crescenzo; Desicato, Sonia; Maro, Salvatore Di; Marinelli, Luciana; Fragale, Alessandra; Buoncervello, Maria; Persico, Francesco; Gabriele, Lucia; Novellino, Ettore; Longo, Nicola; Pignata, Sandro; Perdonà, Sisto; Scala, Stefania

2017-09-29

With the intent to identify biomarkers in renal cell carcinoma (RCC) the functional status of T-regulatory cells (Tregs) was investigated in primary RCC. Tregs were isolated from tumoral-(TT), peritumoral tissue-(PT) and peripheral blood-(PB) of 42 primary RCC patients and function evaluated through effector T cells (Teff) proliferation, cytokines release and demethylation of Treg Specific Region (TSDR). The highest value of Tregs was detected in TT with the uppermost amount of effector-Tregs-(CD4 + CD25 hi FOXP3 hi CD45RA - ). PB-RCC Tregs efficiently suppress Teff proliferation compared to healthy donor (HD)-Tregs and, at the intrapatient evaluation, TT-derived Tregs were the most suppressive. Higher demethylation TSDR was detected in TT- and PB-RCC Tregs vs HD-Tregs ( P <0,001). CXCR4 is highly expressed on Tregs, thus we wished to modulate Tregs function through CXCR4 inhibition. CXCR4 antagonism, elicited by a new peptidic antagonist, Peptide-R29, efficiently reversed Tregs suppression of Teff proliferation. Thus Tregs functional evaluation precisely reflects Tregs status and may be a reliable biomarker of tumoral immune response. In addition, treatment with CXCR4 antagonist, impairing Tregs function, could improve the anticancer immune response, in combination with conventional therapy and/or immunotherapy such as checkpoints inhibitors.

Targeting CXCR4 reverts the suppressive activity of T-regulatory cells in renal cancer

PubMed Central

Santagata, Sara; Napolitano, Maria; D'Alterio, Crescenzo; Desicato, Sonia; Maro, Salvatore Di; Marinelli, Luciana; Fragale, Alessandra; Buoncervello, Maria; Persico, Francesco; Gabriele, Lucia; Novellino, Ettore; Longo, Nicola; Pignata, Sandro; Perdonà, Sisto; Scala, Stefania

2017-01-01

With the intent to identify biomarkers in renal cell carcinoma (RCC) the functional status of T-regulatory cells (Tregs) was investigated in primary RCC. Tregs were isolated from tumoral-(TT), peritumoral tissue-(PT) and peripheral blood-(PB) of 42 primary RCC patients and function evaluated through effector T cells (Teff) proliferation, cytokines release and demethylation of Treg Specific Region (TSDR). The highest value of Tregs was detected in TT with the uppermost amount of effector-Tregs-(CD4+CD25hiFOXP3hiCD45RA-). PB-RCC Tregs efficiently suppress Teff proliferation compared to healthy donor (HD)-Tregs and, at the intrapatient evaluation, TT-derived Tregs were the most suppressive. Higher demethylation TSDR was detected in TT- and PB-RCC Tregs vs HD-Tregs (P <0,001). CXCR4 is highly expressed on Tregs, thus we wished to modulate Tregs function through CXCR4 inhibition. CXCR4 antagonism, elicited by a new peptidic antagonist, Peptide-R29, efficiently reversed Tregs suppression of Teff proliferation. Thus Tregs functional evaluation precisely reflects Tregs status and may be a reliable biomarker of tumoral immune response. In addition, treatment with CXCR4 antagonist, impairing Tregs function, could improve the anticancer immune response, in combination with conventional therapy and/or immunotherapy such as checkpoints inhibitors. PMID:29100374

The Alternative NF-κB Pathway in Regulatory T Cell Homeostasis and Suppressive Function.

PubMed

Grinberg-Bleyer, Yenkel; Caron, Rachel; Seeley, John J; De Silva, Nilushi S; Schindler, Christian W; Hayden, Matthew S; Klein, Ulf; Ghosh, Sankar

2018-04-01

CD4 + Foxp3 + regulatory T cells (Tregs) are essential regulators of immune responses. Perturbation of Treg homeostasis or function can lead to uncontrolled inflammation and autoimmunity. Therefore, understanding the molecular mechanisms involved in Treg biology remains an active area of investigation. It has been shown previously that the NF-κB family of transcription factors, in particular, the canonical pathway subunits, c-Rel and p65, are crucial for the development, maintenance, and function of Tregs. However, the role of the alternative NF-κB pathway components, p100 and RelB, in Treg biology remains unclear. In this article, we show that conditional deletion of the p100 gene, nfkb2 , in Tregs, resulted in massive inflammation because of impaired suppressive function of nfkb2 -deficient Tregs. Surprisingly, mice lacking RelB in Tregs did not exhibit the same phenotype. Instead, deletion of both relb and nfkb2 rescued the inflammatory phenotype, demonstrating an essential role for p100 as an inhibitor of RelB in Tregs. Our data therefore illustrate a new role for the alternative NF-κB signaling pathway in Tregs that has implications for the understanding of molecular pathways driving tolerance and immunity. Copyright © 2018 by The American Association of Immunologists, Inc.

iNOS expression in CD4+ T cells limits Treg induction by repressing TGFβ1: combined iNOS inhibition and Treg depletion unmask endogenous antitumor immunity.

PubMed

Jayaraman, Padmini; Alfarano, Matthew G; Svider, Peter F; Parikh, Falguni; Lu, Geming; Kidwai, Sarah; Xiong, Huabao; Sikora, Andrew G

2014-12-15

Expression of inducible nitric oxide synthase (iNOS) in different cellular compartments may have divergent effects on immune function. We used a syngeneic tumor model to functionally characterize the role of iNOS in regulation of CD4(+)FOXP3(+) regulatory T cells (Treg), and optimize the beneficial effects of iNOS inhibition on antitumor immunity. Wild-type (WT) or iNOS knockout mice bearing established MT-RET-1 melanoma were treated with the small-molecule iNOS inhibitor L-NIL and/or cyclophosphamide alone or in combination. The effect of iNOS inhibition or knockout on induction of Treg from mouse and human CD4(+) T cells in ex vivo culture was determined in parallel in the presence or absence of TGFβ1-depleting antibodies, and TGFβ1 levels were assessed by ELISA. Whereas intratumoral myeloid-derived suppressor cells (MDSC) were suppressed by iNOS inhibition or knockout, systemic and intratumoral FOXP3(+) Treg levels increased in tumor-bearing mice. iNOS inhibition or knockout similarly enhanced induction of Treg from activated cultured mouse splenocytes or purified human or mouse CD4(+) T cells in a TGFβ1-dependent manner. Although either iNOS inhibition or Treg depletion with low-dose cyclophosphamide alone had little effect on growth of established MT-RET1 melanoma, combination treatment potently inhibited MDSC and Treg, boosted tumor-infiltrating CD8(+) T-cell levels, and arrested tumor growth in an immune-dependent fashion. iNOS expression in CD4(+) T cells suppresses Treg induction by inhibiting TGFβ1 production. Our data suggest that iNOS expression has divergent effects on induction of myeloid and lymphoid-derived regulatory populations, and strongly support development of combinatorial treatment approaches that target these populations simultaneously. ©2014 American Association for Cancer Research.

Slc3a2 Mediates Branched-Chain Amino-Acid-Dependent Maintenance of Regulatory T Cells.

PubMed

Ikeda, Kayo; Kinoshita, Makoto; Kayama, Hisako; Nagamori, Shushi; Kongpracha, Pornparn; Umemoto, Eiji; Okumura, Ryu; Kurakawa, Takashi; Murakami, Mari; Mikami, Norihisa; Shintani, Yasunori; Ueno, Satoko; Andou, Ayatoshi; Ito, Morihiro; Tsumura, Hideki; Yasutomo, Koji; Ozono, Keiichi; Takashima, Seiji; Sakaguchi, Shimon; Kanai, Yoshikatsu; Takeda, Kiyoshi

2017-11-14

Foxp3 + regulatory T (Treg) cells, which suppress immune responses, are highly proliferative in vivo. However, it remains unclear how the active replication of Treg cells is maintained in vivo. Here, we show that branched-chain amino acids (BCAAs), including isoleucine, are required for maintenance of the proliferative state of Treg cells via the amino acid transporter Slc3a2-dependent metabolic reprogramming. Mice fed BCAA-reduced diets showed decreased numbers of Foxp3 + Treg cells with defective in vivo proliferative capacity. Mice lacking Slc3a2 specifically in Foxp3 + Treg cells showed impaired in vivo replication and decreased numbers of Treg cells. Slc3a2-deficient Treg cells showed impaired isoleucine-induced activation of the mTORC1 pathway and an altered metabolic state. Slc3a2 mutant mice did not show an isoleucine-induced increase of Treg cells in vivo and exhibited multi-organ inflammation. Taken together, these findings demonstrate that BCAA controls Treg cell maintenance via Slc3a2-dependent metabolic regulation. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Concomitant Mycobacterium tuberculosis infection promotes lung tumor growth through enhancing Treg development.

PubMed

Zhou, Yan; Hu, Zhangguo; Cao, Shuhui; Yan, Bo; Qian, Jialin; Zhong, Hua

2017-08-01

Lung cancer is the most common malignancy in humans. An increased population of CD4+Foxp3+ regulatory T cells (Tregs) in the tumor-associated microenvironment plays an important role in cancer immune evasion. The exact role and the involved mechanisms of concomitant H37Rv infection in non-small cell lung cancer (NSCLC) development are still not clear. Here, we showed that H37Rv infection promoted NSCLC cell growth with a higher percentage of Tregs found in draining lymph nodes. We also determined in vitro that H37Rv infection induced macrophage maturation and PD-L1 expression, which promoted Treg proportion, with enhanced proliferation suppression function. Mechanism analysis revealed that AKT-mTORC1 signal was important for PD-L1 expression induced by H37Rv infection. Suppressing of AKT-mTORC1 signal by rapamycin or raptor deficiency showed decreased PD-L1 levels which further reduced Treg proportion in a co-culture system. Finally, tumor-bearing mice injected with H37Rv plus rapamycin enhance the immune response of lung cancer compared with injected with H37Rv alone. This study demonstrated that concomitant H37Rv infection promote NSCLC tumor immune eacape through enhancing Treg proportion.

Autoimmune Lymphoproliferative Syndrome-FAS Patients Have an Abnormal Regulatory T Cell (Treg) Phenotype but Display Normal Natural Treg-Suppressive Function on T Cell Proliferation.

PubMed

Mazerolles, Fabienne; Stolzenberg, Marie-Claude; Pelle, Olivier; Picard, Capucine; Neven, Benedicte; Fischer, Alain; Magerus-Chatinet, Aude; Rieux-Laucat, Frederic

2018-01-01

Autoimmune lymphoproliferative syndrome (ALPS) with FAS mutation (ALPS-FAS) is a nonmalignant, noninfectious, lymphoproliferative disease with autoimmunity. Given the central role of natural regulatory T cells (nTregs) in the control of lymphoproliferation and autoimmunity, we assessed nTreg-suppressive function in 16 patients with ALPS-FAS. The proportion of CD25 high CD127 low Tregs was lower in ALPS-FAS patients than in healthy controls. This subset was correlated with a reduced CD25 expression in CD3 + CD4 + T cells from ALPS patients and thus an abnormally low proportion of CD25 high FOXP3 + Helios + T cells. The ALPS patients also displayed a high proportion of naïve Treg (FOXP3 low CD45RA + ) and an unusual subpopulation (CD4 + CD127 low CD15s + CD45RA + ). Despite this abnormal phenotype, the CD25 high CD127 low Tregs' suppressive function was unaffected. Furthermore, conventional T cells from FAS -mutated patients showed normal levels of sensitivity to Treg suppression. An abnormal Treg phenotype is observed in circulating lymphocytes of ALPS patients. However, these Tregs displayed a normal suppressive function on T effector proliferation in vitro . This is suggesting that lymphoproliferation observed in ALPS patients does not result from Tregs functional defect or T effector cells insensitivity to Tregs suppression.

Challenges in cryopreservation of regulatory T cells (Tregs) for clinical therapeutic applications.

PubMed

Golab, Karolina; Leveson-Gower, Dennis; Wang, Xiao-Jun; Grzanka, Jakub; Marek-Trzonkowska, Natalia; Krzystyniak, Adam; Millis, J Michael; Trzonkowski, Piotr; Witkowski, Piotr

2013-07-01

Promising results of initial studies applying ex-vivo expanded regulatory T cell (Treg) as a clinical intervention have increased interest in this type of the cellular therapy and several new clinical trials involving Tregs are currently on the way. Methods of isolation and expansion of Tregs have been studied and optimized to the extent that such therapy is feasible, and allows obtaining sufficient numbers of Tregs in the laboratory following Good Manufacturing Practice (GMP) guidelines. Nevertheless, Treg therapy could even more rapidly evolve if Tregs could be efficiently cryopreserved and stored for future infusion or expansions rather than utilization of only freshly isolated and expanded cells as it is preferred now. Currently, our knowledge regarding the impact of cryopreservation on Treg recovery, viability, and functionality is still limited. Based on experience with cryopreserved peripheral blood mononuclear cells (PBMCs), cryopreservation may have a detrimental effect on Tregs, can decrease Treg viability, cause abnormal cytokine secretion, and compromise expression of surface markers essential for proper Treg function and processing. Therefore, optimal strategies and conditions for Treg cryopreservation in conjunction with cell culture, expansion, and processing for clinical application still need to be investigated and defined. Copyright © 2013 Elsevier B.V. All rights reserved.

Bim regulates the survival and suppressive capability of CD8+ FOXP3+ regulatory T cells during murine GVHD.

PubMed

Agle, Kimberle; Vincent, Benjamin G; Piper, Clint; Belle, Ludovic; Zhou, Vivian; Shlomchik, Warren; Serody, Jonathan S; Drobyski, William R

2018-05-16

CD8 + Foxp3 + T cells (Tregs) are a potent regulatory population whose functional and ontological similarities to CD4 + Fox3 + T cells have not been well delineated. Using an experimental model of graft versus host disease (GVHD), we observed that CD8 + Tregs were significantly less potent than CD4 + Tregs for the suppression of GVHD. To define the mechanistic basis for this observation, we examined the T cell repertoire and the transcriptional profile of in vivo-derived CD4 + and CD8 + Tregs that emerged early during this disease. Polyclonal and alloantigen-induced CD8 + Tregs had repertoire diversity that was similar to that of conventional CD8 + T cells, indicating that a restricted repertoire was not the proximate cause of decreased suppression. Transcriptional profiling revealed that CD8 + Tregs possessed a canonical Treg transcriptional signature that was similar to that observed in CD4 + Tregs, yet distinct from conventional CD8 + T cells. Pathway analysis, however, demonstrated that CD8 + Tregs had differential gene expression in pathways involved in cell death and survival. This was further confirmed by detailed mRNA sequence analysis and protein expression studies which demonstrated that CD8 + Tregs had increased expression of Bim and reduced expression of Mcl-1. Transplantation with CD8 + Foxp3 + Bim -/- Tregs resulted in prolonged Treg survival and reduced GVHD lethality compared to wild type CD8 + Tregs, providing functional confirmation that increased expression of Bim was responsible for reduced in vivo efficacy. Thus, Bim regulates the survival and suppressive capability of CD8 + Tregs which may have implications for their use in regulatory T cell therapy. Copyright © 2018 American Society of Hematology.

Effector Regulatory T Cell Differentiation and Immune Homeostasis Depend on the Transcription Factor Myb.

PubMed

Dias, Sheila; D'Amico, Angela; Cretney, Erika; Liao, Yang; Tellier, Julie; Bruggeman, Christine; Almeida, Francisca F; Leahy, Jamie; Belz, Gabrielle T; Smyth, Gordon K; Shi, Wei; Nutt, Stephen L

2017-01-17

FoxP3-expressing regulatory T (Treg) cells are essential for maintaining immune homeostasis. Activated Treg cells undergo further differentiation into an effector state that highly expresses genes critical for Treg cell function, although how this process is coordinated on a transcriptional level is poorly understood. Here, we demonstrate that mice lacking the transcription factor Myb in Treg cells succumbed to a multi-organ inflammatory disease. Myb was specifically expressed in, and required for the differentiation of, thymus-derived effector Treg cells. The combination of transcriptome and genomic footprint analyses revealed that Myb directly regulated a large proportion of the gene expression specific to effector Treg cells, identifying Myb as a critical component of the gene regulatory network controlling effector Treg cell differentiation and function. Copyright © 2017 Elsevier Inc. All rights reserved.

Analyses of a Mutant Foxp3 Allele Reveal BATF as a Critical Transcription Factor in the Differentiation and Accumulation of Tissue Regulatory T Cells.

PubMed

Hayatsu, Norihito; Miyao, Takahisa; Tachibana, Masashi; Murakami, Ryuichi; Kimura, Akihiko; Kato, Takako; Kawakami, Eiryo; Endo, Takaho A; Setoguchi, Ruka; Watarai, Hiroshi; Nishikawa, Takeshi; Yasuda, Takuwa; Yoshida, Hisahiro; Hori, Shohei

2017-08-15

Foxp3 controls the development and function of regulatory T (Treg) cells, but it remains elusive how Foxp3 functions in vivo. Here, we established mouse models harboring three unique missense Foxp3 mutations that were identified in patients with the autoimmune disease IPEX. The I363V and R397W mutations were loss-of-function mutations, causing multi-organ inflammation by globally compromising Treg cell physiology. By contrast, the A384T mutation induced a distinctive tissue-restricted inflammation by specifically impairing the ability of Treg cells to compete with pathogenic T cells in certain non-lymphoid tissues. Mechanistically, repressed BATF expression contributed to these A384T effects. At the molecular level, the A384T mutation altered Foxp3 interactions with its specific target genes including Batf by broadening its DNA-binding specificity. Our findings identify BATF as a critical regulator of tissue Treg cells and suggest that sequence-specific perturbations of Foxp3-DNA interactions can influence specific facets of Treg cell physiology and the immunopathologies they regulate. Copyright © 2017 Elsevier Inc. All rights reserved.

Novel effector phenotype of Tim-3+ regulatory T cells leads to enhanced suppressive function in head and neck cancer patients.

PubMed

Liu, Zhuqing; McMichael, Elizabeth L; Shayan, Gulidanna; Li, Jing; Chen, Kevin; Srivastava, Raghvendra M; Kane, Lawrence P; Lu, Binfeng; Ferris, Robert L

2018-04-30

Regulatory T (Treg) cells are important suppressive cells among tumor infiltrating lymphocytes (TIL). Treg express the well-known immune checkpoint receptor PD-1, which is reported to mark "exhausted" Treg with lower suppressive function. T cell immunoglobulin mucin (Tim)-3, a negative regulator of Th1 immunity, is expressed by a sizeable fraction of TIL Tregs, but the functional status of Tim-3+ Tregs remains unclear. CD4+CTLA-4+CD25high Treg were sorted from freshly excised head and neck squamous cell carcinoma (HNSCC) TIL based on Tim-3 expression. Functional and phenotypic features of these Tim-3+ and Tim-3- TIL Tregs were tested by in vitro suppression assays and multi-color flow cytometry. Gene expression profiling and NanoString analysis of Tim-3+ TIL Treg were performed. A murine HNSCC tumor model was used to test the effect of anti-PD-1 immunotherapy on Tim-3+ Treg.  Results: Despite high PD-1 expression, Tim-3+ TIL Treg displayed a greater capacity to inhibit naïve T cell proliferation than Tim-3- Treg. Tim-3+ Treg from human HNSCC TIL also displayed an effector-like phenotype, with more robust expression of CTLA-4, PD-1, CD39 and IFN-γ receptor. Exogenous IFN-γ treatment could partially reverse the suppressive function of Tim-3+ TIL Treg. Anti-PD-1 immunotherapy downregulated Tim-3 expression on Tregs isolated from murine HNSCC tumors, and this treatment reversed the suppressive function of HNSCC TIL Tregs. Tim-3+ Treg are functionally and phenotypically distinct in HNSCC TIL, and are highly effective at inhibiting T cell proliferation despite high PD-1 expression.  IFN-γ induced by anti-PD-1 immunotherapy may be beneficial by reversing Tim-3+ Treg suppression. Copyright ©2018, American Association for Cancer Research.

Regulatory T cells in Allergic Diseases

PubMed Central

Rivas, Magali Noval; Chatila, Talal A.

2016-01-01

The pathogenesis of allergic diseases entails an ineffective tolerogenic immune response towards allergens. Regulatory T cells (TReg) cells play a key role in sustaining immune tolerance to allergens, yet mechanisms by which TReg cells fail to maintain tolerance in allergic diseases are not well understood. We review current concepts and established mechanisms regarding how TReg cells regulate different components of allergen-triggered immune responses to promote and maintain tolerance. We will also discuss more recent advances that emphasize the “dual” functionality of TReg cells in allergic diseases: how TReg cells are essential in promoting tolerance to allergens but also how a pro-allergic inflammatory environment can skew TReg cells towards a pathogenic phenotype that aggravates and perpetuates disease. These advances highlight opportunities for novel therapeutic strategies that aim to re-establish tolerance in chronic allergic diseases by promoting TReg cell and stability function. PMID:27596705

Foxp3+ regulatory T cells, immune stimulation and host defence against infection

PubMed Central

Rowe, Jared H; Ertelt, James M; Way, Sing Sing

2012-01-01

The immune system is intricately regulated allowing potent effectors to expand and become rapidly mobilized after infection, while simultaneously silencing potentially detrimental responses that averts immune-mediated damage to host tissues. This relies in large part on the delicate interplay between immune suppressive regulatory CD4+ T (Treg) cells and immune effectors that without active suppression by Treg cells cause systemic and organ-specific autoimmunity. Although these beneficial roles have been classically described as counterbalanced by impaired host defence against infection, newfound protective roles for Treg cells against specific viral pathogens (e.g. herpes simplex virus 2, lymphocytic choriomeningitis virus, West Nile virus) have been uncovered using transgenic mice that allow in vivo Treg-cell ablation based on Foxp3 expression. In turn, Foxp3+ Treg cells also provide protection against some parasitic (Plasmodium sp., Toxoplasma gondii) and fungal (Candida albicans) pathogens. By contrast, for bacterial and mycobacterial infections (e.g. Listeria monocytogenes, Salmonella enterica, Mycobacterium tuberculosis), experimental manipulation of Foxp3+ cells continues to indicate detrimental roles for Treg cells in host defence. This variance is probably related to functional plasticity in Treg cell suppression that shifts discordantly following infection with different types of pathogens. Furthermore, the efficiency whereby Treg cells silence immune activation coupled with the plasticity in Foxp3+ cell activity suggest that overriding Treg-mediated suppression represents a prerequisite ‘signal zero’ that together with other stimulation signals [T-cell receptor (signal 1), co-stimulation (signal 2), inflammatory cytokines (signal 3)] are essential for T-cell activation in vivo. Herein, the importance of Foxp3+ Treg cells in host defence against infection, and the significance of infection-induced shifts in Treg-cell suppression are summarized. PMID:22211994

Nuclear matrix protein SMAR1 control regulatory T-cell fate during inflammatory bowel disease (IBD)

PubMed Central

Mirlekar, B; Ghorai, S; Khetmalas, M; Bopanna, R; Chattopadhyay, S

2015-01-01

Regulatory T (Treg) cells are essential for self-tolerance and immune homeostasis. Transcription factor Foxp3, a positive regulator of Treg cell differentiation, has been studied to some extent. Signal transducer and activator of transcription factor 3 (STAT3) is known to negatively regulate Foxp3. It is not clear how STAT3 is regulated during Treg differentiation. We show that SMAR1, a known transcription factor and tumor suppressor, is directly involved in maintaining Treg cell fate decision. T-cell-specific conditional knockdown of SMAR1 exhibits increased susceptibility towards inflammatory disorders, such as colitis. The suppressive function of Treg cells is compromised in the absence of SMAR1 leading to increased T helper type 17 (Th17) differentiation and inflammation. Compared with wild-type, the SMAR1−/− Treg cells showed increased susceptibility of inflammatory bowel disease in Rag1−/− mice, indicating the role of SMAR1 in compromising Treg cell differentiation resulting in severe colitis. We show that SMAR1 negatively regulate STAT3 expression favoring Foxp3 expression and Treg cell differentiation. SMAR1 binds to the MAR element of STAT3 promoter, present adjacent to interleukin-6 response elements. Thus Foxp3, a major driver of Treg cell differentiation, is regulated by SMAR1 via STAT3 and a fine-tune balance between Treg and Th17 phenotype is maintained. PMID:25993445

Safety assessment of immunomodulatory biologics: the promise and challenges of regulatory T-cell modulation.

PubMed

Ponce, Rafael A

2011-01-01

Regulatory T-cell (T(reg)) modulation is developing as an important therapeutic opportunity for the treatment of a number of important diseases, including cancer, autoimmunity, infection, and organ transplant rejection. However, as demonstrated with IL-2 and TGN-1412, our understanding of the complex immunological interactions that occur with T(reg) modulation in both non-clinical models and in patients remains limited and appears highly contextual. This lack of understanding will challenge our ability to identify the patient population who might derive the highest benefit from T(reg) modulation and creates special challenges as we transition these therapeutics from non-clinical models into humans. Thus, in vivo testing in the most representative animal model systems, with careful progress in the clinic, will remain critical in developing therapeutics targeting T(reg) and understanding their clinical utility. Moreover, toxicology models can inform some of the potential liabilities associated with T(reg) modulation, but not all, suggesting a continued need to explore and validate predictive models.

A Special Population of Regulatory T Cells Potentiates Muscle Repair

PubMed Central

Burzyn, Dalia; Kuswanto, Wilson; Kolodin, Dmitriy; Shadrach, Jennifer L.; Cerletti, Massimiliano; Jang, Young; Sefik, Esen; Tan, Tze Guan; Wagers, Amy J.; Benoist, Christophe; Mathis, Diane

2014-01-01

SUMMARY Long recognized to be potent suppressors of immune responses, Foxp3+CD4+ regulatory T (Treg) cells are being rediscovered as regulators of nonimmunological processes. We describe a phenotypically and functionally distinct population of Treg cells that rapidly accumulated in the acutely injured skeletal muscle of mice, just as invading myeloidlineage cells switched from a proinflammatory to a proregenerative state. A Treg population of similar phenotype accumulated in muscles of genetically dystrophic mice. Punctual depletion of Treg cells during the repair process prolonged the proinflammatory infiltrate and impaired muscle repair, while treatments that increased or decreased Treg activities diminished or enhanced (respectively) muscle damage in a dystrophy model. Muscle Treg cells expressed the growth factor Amphiregulin, which acted directly on muscle satellite cells in vitro and improved muscle repair in vivo. Thus, Treg cells and their products may provide new therapeutic opportunities for wound repair and muscular dystrophies. PMID:24315098

Regulatory T Cells and Myeloid-Derived Suppressor Cells in the Tumor Microenvironment Undergo Fas-Dependent Cell Death during IL-2/αCD40 Therapy

PubMed Central

Weiss, Jonathan M.; Subleski, Jeff J.; Back, Tim; Chen, Xin; Watkins, Stephanie K.; Yagita, Hideo; Sayers, Thomas J.; Murphy, William J.

2014-01-01

Fas ligand expression in certain tumors has been proposed to contribute to immunosuppression and poor prognosis. However, immunotherapeutic approaches may elicit the Fas-mediated elimination of immunosuppressive regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) within tumors that represent major obstacles for cancer immunotherapy. Previously, we showed that IL-2 and agonistic CD40 Ab (αCD40) elicited synergistic antitumor responses coincident with the efficient removal of Tregs and MDSCs. We demonstrate in this study in two murine tumor models that Treg and MDSC loss within the tumor microenvironment after IL-2/αCD40 occurs through a Fas-dependent cell death pathway. Among tumor-infiltrating leukocytes, CD8+ T cells, neutrophils, and immature myeloid cells expressed Fas ligand after treatment. Fas was expressed by tumor-associated Tregs and immature myeloid cells, including MDSCs. Tregs and MDSCs in the tumor microenvironment expressed active caspases after IL-2/αCD40 therapy and, in contrast with effector T cells, Tregs significantly downregulated Bcl-2 expression. In contrast, Tregs and MDSCs proliferated and expanded in the spleen after treatment. Adoptive transfer of Fas-deficient Tregs or MDSCs into wild-type, Treg-, or MDSC-depleted hosts resulted in the persistence of Tregs or MDSCs and the loss of antitumor efficacy in response to IL-2/αCD40. These results demonstrate the importance of Fas-mediated Treg/MDSC removal for successful antitumor immunotherapy. Our results suggest that immunotherapeutic strategies that include exploiting Treg and MDSC susceptibility to Fas-mediated apoptosis hold promise for treatment of cancer. PMID:24808361

A requirement of dendritic cell-derived interleukin-27 for the tumor infiltration of regulatory T cells.

PubMed

Xia, Siyuan; Wei, Jun; Wang, Jingya; Sun, Huayan; Zheng, Wenting; Li, Yangguang; Sun, Yanbo; Zhao, Huiyuan; Zhang, Song; Wen, Ti; Zhou, Xinglong; Gao, Jian-Xin; Wang, Puyue; Wu, Zhenzhou; Zhao, Liqing; Yin, Zhinan

2014-05-01

Tregs (Foxp3 + CD4 + ) are enriched in tumors to foster a tolerant microenvironment that inhibits antitumor immune response. IL-27 is reported to regulate the development and function of Tregs in vitro and in vivo; however, the effects of endogenous IL-27 on Tregs in the tumor microenvironment remain elusive. We demonstrated that in the absence of DC-derived IL-27, Tregs were decreased significantly in transplanted B16 melanoma, transplanted EL-4 lymphoma, and MCA-induced fibrosarcoma by using IL-27p28 conditional KO mice. Further studies revealed that IL-27 promoted the expression of CCL22, which is established to mediate the recruitment of peripheral Tregs into tumors. Tumor-associated DCs were identified as the major source of CCL22 in tumor sites, and IL-27 could induce CCL22 expression in an IL-27R-dependent manner. Intratumoral reconstitution of rmCCL22 or rmIL-27, but not rmIL-27p28, significantly restored the tumor infiltration of Tregs in IL-27p28 KO mice. Correlated with a decreased number of Tregs, tumor-infiltrating CD4 T cells were found to produce much more IFN-γ in IL-27p28 KO mice, which highlighted the physiological importance of Tregs in suppressing an antitumor immune response. Overall, our results identified a novel mechanism of action of IL-27 on Tregs in the context of cancers. © 2014 Society for Leukocyte Biology.

Dermal regulatory T cells display distinct migratory behavior that is modulated during adaptive and innate inflammation.

PubMed

Chow, Zachary; Mueller, Scott N; Deane, James A; Hickey, Michael J

2013-09-15

Regulatory T cells (Tregs) are important in controlling skin inflammation, an effect dependent on their ability to home to this organ. However, little is known regarding their behavior in the skin. In this study, we used multiphoton imaging in Foxp3-GFP mice to examine the behavior of endogenous Tregs in resting and inflamed skin. Although Tregs were readily detectable in the uninflamed dermis, most were nonmotile. Induction of contact sensitivity increased the proportion of motile Tregs, and also induced Treg recruitment. This response was significantly blunted in mice challenged with an irrelevant hapten, or by inhibition of effector cell recruitment, indicating a role for T cell-dependent inflammation in induction of Treg migration. Moreover, induction of Treg migration was inhibited by local injection of a CCR4 antagonist, indicating a role for CCR4 in this response. Exposure of naive mice to hapten also induced an increase in the proportion of migratory Tregs, demonstrating that innate signals can also induce Treg migration. Simultaneous examination of the migration of CD4⁺ effector cells and Tregs in the same region of uninflamed skin demonstrated that effector cells behaved differently, being uniformly highly migratory. These findings indicate that Treg behavior in skin differs from that of CD4⁺ effector cells, in that only a low proportion of Tregs is migratory under resting conditions. However, in response to both adaptive and innate inflammation, the proportion of migratory Tregs increases, raising the possibility that this response is important in multiple forms of skin inflammation.

A microRNA profile of human CD8(+) regulatory T cells and characterization of the effects of microRNAs on Treg cell-associated genes.

PubMed

Jebbawi, Fadi; Fayyad-Kazan, Hussein; Merimi, Makram; Lewalle, Philippe; Verougstraete, Jean-Christophe; Leo, Oberdan; Romero, Pedro; Burny, Arsene; Badran, Bassam; Martiat, Philippe; Rouas, Redouane

2014-08-06

Recently, regulatory T (Treg) cells have gained interest in the fields of immunopathology, transplantation and oncoimmunology. Here, we investigated the microRNA expression profile of human natural CD8(+)CD25(+) Treg cells and the impact of microRNAs on molecules associated with immune regulation. We purified human natural CD8(+) Treg cells and assessed the expression of FOXP3 and CTLA-4 by flow cytometry. We have also tested the ex vivo suppressive capacity of these cells in mixed leukocyte reactions. Using TaqMan low-density arrays and microRNA qPCR for validation, we could identify a microRNA 'signature' for CD8(+)CD25(+)FOXP3(+)CTLA-4(+) natural Treg cells. We used the 'TargetScan' and 'miRBase' bioinformatics programs to identify potential target sites for these microRNAs in the 3'-UTR of important Treg cell-associated genes. The human CD8(+)CD25(+) natural Treg cell microRNA signature includes 10 differentially expressed microRNAs. We demonstrated an impact of this signature on Treg cell biology by showing specific regulation of FOXP3, CTLA-4 and GARP gene expression by microRNA using site-directed mutagenesis and a dual-luciferase reporter assay. Furthermore, we used microRNA transduction experiments to demonstrate that these microRNAs impacted their target genes in human primary Treg cells ex vivo. We are examining the biological relevance of this 'signature' by studying its impact on other important Treg cell-associated genes. These efforts could result in a better understanding of the regulation of Treg cell function and might reveal new targets for immunotherapy in immune disorders and cancer.

mTOR Complex 1 Signaling Regulates the Generation and Function of Central and Effector Foxp3+ Regulatory T Cells.

PubMed

Sun, Im-Hong; Oh, Min-Hee; Zhao, Liang; Patel, Chirag H; Arwood, Matthew L; Xu, Wei; Tam, Ada J; Blosser, Richard L; Wen, Jiayu; Powell, Jonathan D

2018-06-08

The mechanistic/mammalian target of rapamycin (mTOR) has emerged as a critical integrator of signals from the immune microenvironment capable of regulating T cell activation, differentiation, and function. The precise role of mTOR in the control of regulatory T cell (Treg) differentiation and function is complex. Pharmacologic inhibition and genetic deletion of mTOR promotes the generation of Tregs even under conditions that would normally promote generation of effector T cells. Alternatively, mTOR activity has been observed to be increased in Tregs, and the genetic deletion of the mTOR complex 1 (mTORC1)-scaffold protein Raptor inhibits Treg function. In this study, by employing both pharmacologic inhibitors and genetically altered T cells, we seek to clarify the role of mTOR in Tregs. Our studies demonstrate that inhibition of mTOR during T cell activation promotes the generation of long-lived central Tregs with a memory-like phenotype in mice. Metabolically, these central memory Tregs possess enhanced spare respiratory capacity, similar to CD8 + memory cells. Alternatively, the generation of effector Tregs (eTregs) requires mTOR function. Indeed, genetic deletion of Rptor leads to the decreased expression of ICOS and PD-1 on the eTregs. Overall, our studies define a subset of mTORC1 hi eTregs and mTORC1 lo central Tregs. Copyright © 2018 by The American Association of Immunologists, Inc.

Pregnancy-associated diseases are characterized by the composition of the systemic regulatory T cell (Treg) pool with distinct subsets of Tregs.

PubMed

Steinborn, A; Schmitt, E; Kisielewicz, A; Rechenberg, S; Seissler, N; Mahnke, K; Schaier, M; Zeier, M; Sohn, C

2012-01-01

Dysregulations concerning the composition and function of regulatory T cells (T(regs)) are assumed to be involved in the pathophysiology of complicated pregnancies. We used six-colour flow cytometric analysis to demonstrate that the total CD4(+) CD127(low+/-) CD25(+) forkhead box protein 3 (FoxP3)(+) T(reg) cell pool contains four distinct T(reg) subsets: DR(high+) CD45RA(-), DR(low+) CD45RA(-), DR(-) CD45RA(-) T(regs) and naive DR(-) CD45RA(+) T(regs). During the normal course of pregnancy, the most prominent changes in the composition of the total T(reg) cell pool were observed between the 10th and 20th weeks of gestation, with a clear decrease in the percentage of DR(high+) CD45RA(-) and DR(low+) CD45RA(-) T(regs) and a clear increase in the percentage of naive DR(-) CD45RA(+) T(regs). After that time, the composition of the total T(reg) cell pool did not change significantly. Its suppressive activity remained stable during normally progressing pregnancy, but decreased significantly at term. Compared to healthy pregnancies the composition of the total T(reg) cell pool changed in the way that its percentage of naive DR(-) CD45RA(+) T(regs) was reduced significantly in the presence of pre-eclampsia and in the presence of preterm labour necessitating preterm delivery (PL). Interestingly, its percentage of DR(high+) CD45RA(-) and DR(low+) CD45RA(-) T(regs) was increased significantly in pregnancies affected by pre-eclampsia, while PL was accompanied by a significantly increased percentage of DR(-) CD45RA(-) and DR(low+) CD45RA(-) T(regs). The suppressive activity of the total T(reg) cell pool was diminished in both patient collectives. Hence, our findings propose that pre-eclampsia and PL are characterized by homeostatic changes in the composition of the total T(reg) pool with distinct T(reg) subsets that were accompanied by a significant decrease of its suppressive activity. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.

Impairment of T-regulatory cells in cord blood of atopic mothers.

PubMed

Schaub, Bianca; Liu, Jing; Höppler, Sabine; Haug, Severine; Sattler, Christine; Lluis, Anna; Illi, Sabina; von Mutius, Erika

2008-06-01

Maternal atopy is a strong predictor for the development of childhood allergic diseases. The underlying mechanisms are ill defined, yet regulatory T (Treg) and T(H)17 cells may play a key role potentially shaping the early immune system toward a proallergic or antiallergic immune regulation. We examined T(H)1/T(H)2, Treg, and T(H)17 cell responses to innate (lipid A/peptidoglycan) and mitogen/adaptive (phytohemagglutinin/Dermatophagoides pteronyssinus 1) immune stimulation in cord blood from offspring of atopic/nonatopic mothers. Cord blood mononuclear cells from 161 healthy neonates (59% nonatopic, 41% atopic mothers) were investigated regarding Treg and T(H)17 cells (mRNA/surface markers), suppressive function, and proliferation/cytokine secretion. Cord blood from offspring of atopic mothers showed fewer innate-induced Treg cells (CD4(+)CD25(+)high), lower mRNA expression of associated markers (glucocorticoid-induced tumor necrosis factor receptor-related protein/lymphocyte activation gene 3; P < .05), and a trend toward lower Forkhead box transcription factor 3 (Foxp3) expression. Treg cell function was impaired in mitogen-induced suppression of T effector cells in cord blood of offspring from atopic mothers (P = .03). Furthermore, IL-10 and IFN-gamma secretion were decreased in innate-stimulated cord blood of offspring from atopic mothers (P = .04/.05). Innate-induced IL-17 was independent of maternal atopy and highly correlated with IL-13 secretion. In offspring of atopic mothers, Treg cell numbers, expression, and function were impaired at birth. T(H)17 cells were correlated with T(H)2 cells, independently of maternal atopy.

CD11c-expressing cells affect Treg behavior in the meninges during CNS infection1

PubMed Central

O’Brien, Carleigh A.; Overall, Christopher; Konradt, Christoph; O’Hara Hall, Aisling C.; Hayes, Nikolas W.; Wagage, Sagie; John, Beena; Christian, David A.; Hunter, Christopher A.; Harris, Tajie H.

2017-01-01

Treg cells play an important role in the CNS during multiple infections as well as autoimmune inflammation, but the behavior of this cell type in the CNS has not been explored. In mice, infection with Toxoplasma gondii leads to a Th1-polarized parasite-specific effector T cell response in the brain. Similarly, the Treg cells in the CNS during T. gondii infection are Th1-polarized, exemplified by T-bet, CXCR3, and IFN-γ expression. Unlike effector CD4+ T cells, an MHC Class II tetramer reagent specific for T. gondii did not recognize Treg cells isolated from the CNS. Likewise, TCR sequencing revealed minimal overlap in TCR sequence between effector and regulatory T cells in the CNS. Whereas effector T cells are found in the brain parenchyma where parasites are present, Treg cells were restricted to the meninges and perivascular spaces. The use of intravital imaging revealed that activated CD4+ T cells within the meninges were highly migratory, while Treg cells moved more slowly and were found in close association with CD11c+ cells. To test whether the behavior of Tregs in the meninges is influenced by interactions with CD11c+ cells, mice were treated with anti-LFA-1 antibodies to reduce the number of CD11c+ cells in this space. The anti-LFA-1 treatment led to fewer contacts between Tregs and the remaining CD11c+ cells and increased the speed of Treg cell migration. These data suggest that Treg cells are anatomically restricted within the CNS and the interaction with CD11c+ populations regulates their local behavior during T. gondii infection. PMID:28389591

Effect of chorioamnionitis on regulatory T cells in moderate/late preterm neonates☆

PubMed Central

Rueda, Cesar M.; Wells, Casey B.; Gisslen, Tate; Jobe, Alan H.; Kallapur, Suhas G.; Chougnet, Claire A.

2014-01-01

Regulatory T-cells (Treg) have a protective role for the control of immune activation and tissue damage. The effects of chorioamnionitis (chorio) on Treg in moderate/late preterm newborns are not known. We hypothesized that infants exposed to chorio would have decreased Treg frequency and/or function. We isolated mononuclear cells from adult peripheral blood and cord blood from term and moderate/late preterm infants who were classified for severity of chorio exposure. Mononuclear cells were analyzed by flow cytometry for Treg frequency and phenotype. Treg suppression of activation of conventional T-cells (Tcon) was also quantified. Treg frequencies were similar in all groups of neonates, but lower than that found in adults. Newborn Treg had a naïve phenotype, with decreased levels of CD45RO, HLA-DR, CD39 and TIGIT compared to adult Treg and chorio did not affect the phenotype. Treg from preterm newborns exposed to severe chorio had higher expression of Ki67 compared to the other groups. Treg from preterm newborns were less suppressive than Treg from adults or term, and the level of suppression was reduced with severe chorio. Relative to term, Treg frequency and phenotype were not affected by prematurity and chorio but their functionality was decreased. Lower Treg activity may contribute to inflammation in newborns that is often associated with chorioamnionitis. PMID:25451985

Dendritic Cells Induce a Subpopulation of IL-12Rβ2-Expressing Treg that Specifically Consumes IL-12 to Control Th1 Responses

PubMed Central

Sela, Uri; Park, Chae Gyu; Park, Andrew; Olds, Peter; Wang, Shu; Fischetti, Vincent A.

2016-01-01

Cytokines secreted from dendritic cells (DCs) play an important role in the regulation of T helper (Th) cell differentiation and activation into effector cells. Therefore, controlling cytokine secretion from DCs may potentially regulate Th differentiation/activation. DCs also induce de-novo generation of regulatory T cells (Treg) that modulate the immune response. In the current study we used the mixed leukocyte reaction (MLR) to investigate the effect of allospecific Treg on IL-12, TNFα and IL-6 secretion by DCs. Treg cells were found to markedly down-regulate IL-12 secretion from DCs following stimulation with TLR7/8 agonist. This down-regulation of IL-12 was neither due to a direct suppression of its production by the DCs nor a result of marked DC death. We found that IL-12 was rather actively consumed by Treg cells. IL-12 consumption was mediated by a subpopulation of IL-12Rβ2-expressing Treg cells and was dependent on MHC class-II expressed on dendritic cells. Furthermore, IL-12 consumption by Tregs increased their suppressive effect on T cell proliferation and Th1 activation. These results provide a new pathway of Th1 response regulation where IL-12 secreted by DCs is consumed by a sub-population of IL-12Rβ2-expressing Treg cells. Consumption of IL-12 by Tregs not only reduces the availability of IL-12 to Th effector cells but also enhances the Treg immunosuppressive effect. This DC-induced IL-12Rβ2-expressing Treg subpopulation may have a therapeutic advantage in suppressing Th1 mediated autoimmunity. PMID:26745371

Deltex1 antagonizes HIF-1α and sustains the stability of regulatory T cells in vivo

PubMed Central

Hsiao, Huey-Wen; Hsu, Tzu-Sheng; Liu, Wen-Hsien; Hsieh, Wan-Chen; Chou, Ting-Fang; Wu, Yu-Jung; Jiang, Si-Tse; Lai, Ming-Zong

2015-01-01

Application of regulatory T cells (Tregs) in transplantation, autoimmunity and allergy has been extensively explored, but how Foxp3 and Treg stability is regulated in vivo is incompletely understood. Here, we identify a requirement for Deltex1 (DTX1), a contributor to T-cell anergy and Foxp3 protein level maintenance in vivo. Dtx1−/− Tregs are as effective as WT Tregs in the inhibition of CD4+CD25− T-cell activation in vitro. However, the suppressive ability of Dtx1−/− Tregs is greatly impaired in vivo. We find that Foxp3 expression is diminished when Dtx1−/− Tregs are co-transferred with effector T cells in vivo. DTX1 promotes the degradation of HIF-1α. Knockout of HIF-1α restores the Foxp3 stability and rescues the defective suppressive activity in Dtx1−/− Treg cells in vivo. Our results suggest that DTX1 exerts another level of control on Treg stability in vivo by sustaining the expression of Foxp3 protein in Tregs. PMID:25695215

Donor CD4+ Foxp3+ regulatory T cells are necessary for posttransplantation cyclophosphamide-mediated protection against GVHD in mice

PubMed Central

Ganguly, Sudipto; Ross, Duncan B.; Panoskaltsis-Mortari, Angela; Kanakry, Christopher G.; Blazar, Bruce R.; Levy, Robert B.

2014-01-01

Posttransplantation cyclophosphamide (PTCy) is an effective prophylaxis against graft-versus-host disease (GVHD). However, it is unknown whether PTCy works singularly by eliminating alloreactive T cells via DNA alkylation or also by restoring the conventional (Tcon)/regulatory (Treg) T-cell balance. We studied the role of Tregs in PTCy-mediated GVHD prophylaxis in murine models of allogeneic blood or marrow transplantation (alloBMT). In 2 distinct MHC-matched alloBMT models, infusing Treg-depleted allografts abrogated the GVHD-prophylactic activity of PTCy. Using allografts in which Foxp3+ Tregs could be selectively depleted in vivo, either pre- or post-PTCy ablation of donor thymus–derived Tregs (tTregs) abolished PTCy protection against GVHD. PTCy treatment was associated with relative preservation of donor Tregs. Experiments using combinations of Foxp3– Tcons and Foxp3+ Tregs sorted from different Foxp3 reporter mice indicated that donor Treg persistence after PTCy treatment was predominantly caused by survival of functional tTregs that retained Treg-specific demethylation and also induction of peripherally derived Tregs. Finally, adoptive transfer of tTregs retrieved from PTCy-treated chimeras rescued PTCy-treated, Treg-depleted recipients from lethal GVHD. Our findings indicate that PTCy-mediated protection against GVHD is not singularly dependent on depletion of donor alloreactive T cells but also requires rapidly recovering donor Tregs to initiate and maintain alloimmune regulation. PMID:25139358

Cloning of feline FOXP3 and detection of expression in CD4+CD25+ regulatory T cells

PubMed Central

Lankford, Susan; Petty, Christopher; LaVoy, Alora; Reckling, Stacie; Tompkins, Wayne; Dean, Gregg A.

2008-01-01

Regulatory T cells (Treg) are increased and directly infected by feline immunodeficiency virus (FIV) and likely play a role in other feline autoimmune, neoplastic, and infectious diseases. Phenotypically, Treg are best characterized by surface expression of CD4 and CD25 and intranuclear expression of the forkhead transcription factor Foxp3. Our objective was to clone and sequence feline FOXP3 for the purpose of developing assays to enhance studies of feline Treg. We determined the feline FOXP3 is 1293 nucleotides in length and codes for a protein that shares high homology to other species. A splice variant devoid of exon 2 was also identified. A real-time PCR assay was developed and used to show Foxp3 mRNA expression occurs primarily in CD4+CD25+ T cells. Two cross-reacting antibodies were identified by immunocytochemical staining of HEK293 cells transfected with feline FOXP3. The antibody labeling confirmed the nuclear localization of the protein. A flow cytometric assay was also validated and used to correlate the phenotypic and functional characteristics of feline Treg induced by treatment of lymph node lymphocytes with flagellin or LPS in combination with mitogen or IL2. Together, these studies provide useful tools to further investigate Foxp3 and Tregs in cats. PMID:18180044

Immunotherapy with myeloid cells for tolerance induction

PubMed Central

Rodriguez-García, Mercedes; Boros, Peter; Bromberg, Jonathan S.; Ochando, Jordi C.

2013-01-01

Purpose of review Understanding the interplay between myeloid dendritic cells and T cells under tolerogenic conditions, and whether their interactions induce the development of antigen-specific regulatory T cells (Tregs) is critical to uncover the mechanisms involved in the induction of indefinite allograft survival. Recent findings Myeloid dendritic cell–T-cell interactions are seminal events that determine the outcome of the immune response, and multiple in-vitro protocols suggest the generation of tolerogenic myeloid dendritic cells that modulate T-cell responses, and determine the outcome of the immune response to an allograft following adoptive transfer. We believe that identifying specific conditions that lead to the generation of tolerogenic myeloid dendritic cells and Tregs are critical for the manipulation the immune response towards the development of transplantation tolerance. Summary We summarize recent findings regarding specific culture conditions that generate tolerogenic myeloid dendritic cells that induce T-cell hyporesponsiveness and Treg development, and represents a novel immunotherapeutic approach to promote the induction of indefinite graft survival prolongation. The interpretations presented here illustrate that different mechanisms govern the generation tolerogenic myeloid dendritic cells, and we discuss the concomitant therapeutic implications. PMID:20616727

Regulatory T-cell stability and plasticity in mucosal and systemic immune systems.

PubMed

Murai, M; Krause, P; Cheroutre, H; Kronenberg, M

2010-09-01

Regulatory T cells (Treg) express the forkhead box p3 (Foxp3) transcription factor and suppress pathological immune responses against self and foreign antigens, including commensal microorganisms. Foxp3 has been proposed as a master key regulator for Treg, required for their differentiation, maintenance, and suppressive functions. Two types of Treg have been defined. Natural Treg (nTreg) are usually considered to be a separate sublineage arising during thymus differentiation. Induced Treg (iTreg) originate upon T cell receptor (TCR) stimulation in the presence of tumor growth factor beta. Although under homeostatic conditions most Treg in the periphery are nTreg, special immune challenges in the intestine promote more frequently the generation of iTreg. Furthermore, recent observations have challenged the notion that Treg are a stable sublineage, and they suggest that, particularly under lymphopenic and/or inflammatory conditions, Treg may lose Foxp3 and/or acquire diverse effector functions, especially in the intestine, which may contribute to uncontrolled inflammation.

Level of Granzyme B-positive T-regulatory cells is a strong predictor biomarker of acute Graft-versus-host disease after day +30 after allo-HSCT.

PubMed

Drokov, Mikhail Y; Davydova, Julia O; Kuzmina, Larisa A; Galtseva, Irina V; Kapranov, Nikolay M; Vasilyeva, Vera A; Dubnyak, Darya S; Koroleva, Olga M; Mikhalcova, Ekaterina D; Popova, Natalia N; Parovichnikova, Elena N; Savchenko, Valery G

2017-03-01

Acute Graft-versus-host-disease (aGVHD), the major complication and one of the main causes of poor outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Nowadays there are no widely accepted cell, plasma or another biomarker that can be used for aGVHD prediction. We hypothesized that a level of Granzyme B-positive T regulatory (GZMB-positive Treg) cells on day+30 after allo-HSCT could be the measure of immune response suppression and could predict aGVHD development after day +30. We applied a widespread and easy-to-perform method of multicolor flow cytometry to measure level of GZMB-positive Treg cells. Levels of GZMB-positive Tregs on day +30 after allo-HSCT were significantly higher in those patients who never developed aGVHD in comparison with the other group of patient with aGVHD after day +30 (p=0.0229). We conclude that the level of GZMB-positive Treg cells is a strong predictor of acute Graft-versus-host disease after day +30 after allo-HSCT. Copyright © 2017 Elsevier Ltd. All rights reserved.

Regulatory T-cells in autoimmune diseases: challenges, controversies and--yet--unanswered questions.

PubMed

Grant, Charlotte R; Liberal, Rodrigo; Mieli-Vergani, Giorgina; Vergani, Diego; Longhi, Maria Serena

2015-02-01

Regulatory T cells (Tregs) are central to the maintenance of self-tolerance and tissue homeostasis. Markers commonly used to define human Tregs in the research setting include high expression of CD25, FOXP3 positivity and low expression/negativity for CD127. Many other markers have been proposed, but none unequivocally identifies bona fide Tregs. Tregs are equipped with an array of mechanisms of suppression, including the modulation of antigen presenting cell maturation and function, the killing of target cells, the disruption of metabolic pathways and the production of anti-inflammatory cytokines. Treg impairment has been reported in a number of human autoimmune conditions and includes Treg numerical and functional defects and conversion into effector cells in response to inflammation. In addition to intrinsic Treg impairment, resistance of effector T cells to Treg control has been described. Discrepancies in the literature are common, reflecting differences in the choice of study participants and the technical challenges associated with investigating this cell population. Studies differ in terms of the methodology used to define and isolate putative regulatory cells and to assess their suppressive function. In this review we outline studies describing Treg frequency and suppressive function in systemic and organ specific autoimmune diseases, with a specific focus on the challenges faced when investigating Tregs in these conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Evidence for a role of regulatory T cells in mediating the atheroprotective effect of apolipoprotein B peptide vaccine.

PubMed

Wigren, M; Kolbus, D; Dunér, P; Ljungcrantz, I; Söderberg, I; Björkbacka, H; Fredrikson, G N; Nilsson, J

2011-05-01

Autoimmune responses against oxidized low-density lipoprotein are considered to play an important pro-inflammatory role in atherosclerosis and to promote disease progression. T-regulatory cells (Tregs) are immunosuppressive cells that have an important part in maintaining self-tolerance and protection against autoimmunity. We investigated whether aBp210, a prototype atherosclerosis vaccine based on a peptide sequence derived from apolipoprotein B, inhibits atherosclerosis through the activation of Tregs. Six-week-old Apoe(-/-) mice were immunized with aBp210 and received booster immunizations 3 and 5 weeks later, as well as 1 week before being killed at 25 weeks of age. At 12 weeks, immunized mice had increased expression of the Treg marker CD25 on circulating CD4 cells, and concanavalin A (Con A)-induced interferon-γ, interleukin (IL)-4, and IL-10 release from splenocytes was markedly depressed. At 25 weeks, there was a fivefold expansion of splenic CD4+ CD25+ Foxp3 Tregs, a 65% decrease in Con A-induced splenic T-cell proliferation and a 37% reduction in the development of atherosclerosis in immunized mice. Administration of blocking antibodies against CD25 neutralized aBp210-induced Treg activation as well as the reduction of atherosclerosis. The present findings demonstrate that immunization of Apoe(-/-) mice with the apolipoprotein B peptide vaccine aBp210 is associated with activation of Tregs. Administration of antibodies against CD25 results in depletion of Tregs and blocking of the atheroprotective effect of the vaccine. Modulation in atherosclerosis-related autoimmunity by antigen-specific activation of Tregs represents a novel approach for treatment of atherosclerosis. © 2010 The Association for the Publication of the Journal of Internal Medicine.

Review: Transcriptional Regulation of CD4+ T Cell Differentiation in Experimentally Induced Arthritis and Rheumatoid Arthritis.

PubMed

Kondo, Yuya; Yokosawa, Masahiro; Kaneko, Shunta; Furuyama, Kotona; Segawa, Seiji; Tsuboi, Hiroto; Matsumoto, Isao; Sumida, Takayuki

2018-05-01

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation of the joint synovium and infiltration by activated inflammatory cells. CD4+ T cells form a large proportion of the inflammatory cells invading the synovial tissue, and are involved in the RA pathologic process. In general, CD4+ T cells differentiate into various T helper cell subsets and acquire the functional properties to respond to specific pathogens, and also mediate some autoimmune disorders such as RA. Because the differentiation of T helper cell subsets is determined by the expression of specific transcription factors in response to the cytokine environment, these transcription factors are considered to have a role in the pathology of RA. Treg cells control an excess of T cell-mediated immune response, and the transcription factor FoxP3 is critical for the differentiation and function of Treg cells. Treg cell dysfunction can result in the development of systemic autoimmunity. In this review, we summarize how the expression of transcription factors modulates T helper cell immune responses and the development of autoimmune diseases, especially in RA. Understanding the role of transcription factors in the pathogenesis of autoimmunity may lead to novel therapeutic strategies to control the differentiation and function of both T helper cells and Treg cells. © 2017 The Authors. Arthritis & Rheumatology published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.

The effect of inhibitory signals on the priming of drug-hapten-specific T-cells that express distinct Vβ receptors

PubMed Central

Gibson, Andrew; Faulkner, Lee; Lichtenfels, Maike; Ogese, Monday; Al-Attar, Zaid; Alfirevic, Ana; Esser, Philipp R.; Martin, Stefan F.; Pirmohamed, Munir; Park, B. Kevin; Naisbitt, Dean J.

2017-01-01

Drug hypersensitivity involves the activation of T-cells in an HLA allele-restricted manner. Since the majority of individuals who carry HLA risk alleles do not develop hypersensitivity, other parameters must control development of the drug-specific T-cell response. Thus, we have utilized a T-cell priming assay and nitroso sulfamethoxazole (SMX-NO) as a model antigen to investigate (1) the activation of specific T-cell receptor (TCR)Vβ subtypes, (2) the impact of PD-1, CTLA4 and TIM-3 co-inhibitory signalling on activation of naïve and memory T-cells and (3) the ability of Tregs to prevent responses. An expansion of the TCR repertoire was observed for nine different Vβ subtypes, while spectratyping revealed that SMX-NO-specific T-cell responses are controlled by public TCRs present in all individuals alongside private TCR repertoires specific to each individual. We proceeded to evaluate the extent to which the activation of these TCR Vβ-restricted antigen-specific T-cell responses is governed by regulatory signals. Blockade of PDL-1/CTLA4 signalling dampened activation of SMX-NO-specific naïve and memory T-cells, while blockade of TIM-3 produced no effect. PD-1, CTLA4, and TIM-3 displayed discrete expression profiles during drug-induced T-cell activation and expression of each receptor was enhanced on dividing T-cells. As these receptors are also expressed on Tregs, Treg-mediated suppression of SMX-NO-induced T-cell activation was investigated. Tregs significantly dampened the priming of T-cells. In conclusion, our findings demonstrate that distinct TCR Vβ subtypes, dysregulation of co-inhibitory signalling pathways and dysfunctional Tregs may influence predisposition to hypersensitivity. PMID:28687658

Non-suppressive regulatory T cell subset expansion in pulmonary arterial hypertension.

PubMed

Sada, Yoshiharu; Dohi, Yoshihiro; Uga, Sayuri; Higashi, Akifumi; Kinoshita, Hiroki; Kihara, Yasuki

2016-08-01

Regulatory T cells (Tregs) have been reported to play a pivotal role in the vascular remodeling of pulmonary arterial hypertension (PAH). Recent studies have revealed that Tregs are heterogeneous and can be characterized by three phenotypically and functionally different subsets. In this study, we investigated the roles of Treg subsets in the pathogenesis of PAH in eight patients with PAH and 14 healthy controls. Tregs and their subsets in peripheral blood samples were analyzed by flow cytometry. Treg subsets were defined as CD4(+)CD45RA(+)FoxP3(low) resting Tregs (rTregs), CD4(+)CD45RA(-)FoxP3(high) activated Tregs (aTregs), and CD4(+)CD45RA(-)FoxP3(low) non-suppressive Tregs (non-Tregs). The proportion of Tregs among CD4(+) T cells was significantly higher in PAH patients than in controls (6.54 ± 1.10 vs. 3.81 ± 0.28 %, p < 0.05). Of the three subsets, the proportion of non-Tregs was significantly elevated in PAH patients compared with controls (4.06 ± 0.40 vs. 2.79 ± 0.14 %, p < 0.01), whereas those of rTregs and aTregs were not different between the two groups. Moreover, the expression levels of cytotoxic T lymphocyte antigen 4, a functional cell surface molecule, in aTregs (p < 0.05) and non-Tregs (p < 0.05) were significantly higher in PAH patients compared with controls. These results suggested the non-Treg subset was expanded and functionally activated in peripheral lymphocytes obtained from IPAH patients. We hypothesize that immunoreactions involving the specific activation of the non-Treg subset might play a role in the vascular remodeling of PAH.

An inherently bi-functional subset of Foxp3+ T helper cells is controlled by the transcription factor Eos

PubMed Central

Sharma, Madhav D.; Huang, Lei; Choi, Jeong-Hyeon; Lee, Eun-Joon; Wilson, James M.; Lemos, Henrique; Pan, Fan; Blazar, Bruce R.; Pardoll, Drew M.; Mellor, Andrew L; Shi, Huidong; Munn, David H.

2013-01-01

SUMMARY At sites of inflammation, certain regulatory T cells (Treg cells) can undergo rapid reprogramming into helper-like cells, without loss of the transcription factor Foxp3. We show that reprogramming is controlled by down-regulation of the transcription factor Eos (Ikzf4), an obligate co-repressor for Foxp3. Reprogramming was restricted to a specific subset of “Eoslabile” Treg cells which were present in the thymus and identifiable by characteristic surface markers and DNA methylation. Mice made deficient in this subset became impaired in their ability to provide help for presentation of new antigens to naive T cells. Down-regulation of Eos required the pro-inflammatory cytokine IL-6, and mice lacking IL-6 had impaired development and function of the Eos-labile subset. Conversely, the immunoregulatory enzyme IDO blocked loss of Eos, and prevented the Eos-labile Treg cells from reprogramming. Thus, the Foxp3+ lineage contains a committed subset of Treg cells capable of rapid conversion into biologically important helper cells. PMID:23684987

A major role for Bim in regulatory T cell homeostasis.

PubMed

Chougnet, Claire A; Tripathi, Pulak; Lages, Celine S; Raynor, Jana; Sholl, Allyson; Fink, Pamela; Plas, David R; Hildeman, David A

2011-01-01

We have previously shown that regulatory T cells (Treg) accumulate dramatically in aged animals and negatively impact the ability to control persistent infection. However, the mechanisms underlying the age-dependent accrual of Treg remain unclear. In this study, we show that Treg accumulation with age is progressive and likely not the result of increased thymic output, increased peripheral proliferation, or from enhanced peripheral conversion. Instead, we found that Treg from aged mice are more resistant to apoptosis than Treg from young mice. Although Treg from aged mice had increased expression of functional IL-7Rα, we found that IL-7R signaling was not required for maintenance of Treg in vivo. Notably, aged Treg exhibit decreased expression of the proapoptotic molecule Bim compared with Treg from young mice. Furthermore, in the absence of Bim, Treg accumulate rapidly, accounting for >25% of the CD4(+) T cell compartment by 6 mo of age. Additionally, accumulation of Treg in Bim-deficient mice occurred after the cells left the transitional recent thymic emigrant compartment. Mechanistically, we show that IL-2 drives preferential proliferation and accumulation of Bim(lo) Treg. Collectively, our data suggest that chronic stimulation by IL-2 leads to preferential expansion of Treg having low expression of Bim, which favors their survival and accumulation in aged hosts.

A major role for Bim in regulatory T cell homeostasis1

PubMed Central

Chougnet, Claire A.; Tripathi, Pulak; Lages, Celine S.; Raynor, Jana; Sholl, Allyson; Fink, Pamela; Plas, David R.; Hildeman, David A.

2011-01-01

We have previously shown that regulatory T cells (Treg) accumulate dramatically in aged animals and negatively impact the ability to control persistent infection. However, the mechanism(s) underlying the age-dependent accrual of Treg remain unclear. Here, we show that Treg accumulation with age is progressive and likely not the result of increased thymic output, increased peripheral proliferation, nor from enhanced peripheral conversion. Instead, we found that Treg from aged mice are more resistant to apoptosis than Treg from young mice. Although Treg from aged mice had increased expression of functional IL-7Rα, we found that IL-7R-signaling was not required for maintenance of Treg in vivo. Notably, aged Treg exhibit decreased expression of the pro-apoptotic molecule Bim compared to Treg from young mice. Further, in the absence of Bim, Treg accumulate rapidly, accounting for more than 25% of the CD4+ T cell compartment by 6 months of age. In addition, accumulation of Treg in Bim-deficient mice occurred after the cells left the transitional recent thymic emigrant compartment. Mechanistically, we show that IL-2 drives preferential proliferation and accumulation of Bimlo Treg. Combined, our data suggest that chronic stimulation by IL-2 leads to preferential expansion of Treg having low expression of Bim, which favors their survival and accumulation in aged hosts. PMID:21098226

FOXP3+ regulatory T cells in normal prostate tissue, postatrophic hyperplasia, prostatic intraepithelial neoplasia, and tumor histological lesions in men with and without prostate cancer

PubMed Central

Andren, Ove; Ohlson, Anna‐Lena; Carlsson, Jessica; Andersson, Swen‐Olof; Giunchi, Francesca; Rider, Jennifer R.; Fiorentino, Michelangelo

2017-01-01

Background The tumor promoting or counteracting effects of the immune response to cancer development are thought to be mediated to some extent by the infiltration of regulatory T cells (Tregs). In the present study we evaluated the prevalence of Treg populations in stromal and epithelial compartments of normal, post atrophic hyperplasia (PAH), prostatic intraepithelial neoplasia (PIN), and tumor lesions in men with and without prostate cancer. Methods Study subjects were 102 men consecutively diagnosed with localized prostate cancer undergoing radical prostatectomy and 38 men diagnosed with bladder cancer undergoing cystoprostatectomy without prostate cancer at the pathological examination. Whole mount sections from all patients were evaluated for the epithelial and stromal expression of CD4+ Tregs and CD8+ Tregs in normal, PAH, PIN, and tumor lesions. A Friedmańs test was used to investigate differences in the mean number of Tregs across histological lesions. Logistic regression was used to estimate crude and adjusted odds ratios (OR) for prostate cancer for each histological area. Results In men with prostate cancer, similarly high numbers of stromal CD4+ Tregs were identified in PAH and tumor, but CD4+ Tregs were less common in PIN. Greater numbers of epithelial CD4+ Tregs in normal prostatic tissue were positively associated with both Gleason score and pT‐stage. We observed a fourfold increased risk of prostate cancer in men with epithelial CD4+ Tregs in the normal prostatic tissue counterpart. Conclusions Our results may suggest a possible pathway through which PAH develops directly into prostate cancer in the presence of CD4+ Tregs and indicate that transformation of the anti‐tumor immune response may be initiated even before the primary tumor is established. PMID:29105795

In patients with chronic aplastic anemia, bone marrow-derived MSCs regulate the Treg/Th17 balance by influencing the Notch/RBP-J/FOXP3/RORγt pathway.

PubMed

Li, Hongbo; Wang, Lin; Pang, Yan; Jiang, Zujun; Liu, Zenghui; Xiao, Haowen; Chen, Haijia; Ge, Xiaohu; Lan, Hai; Xiao, Yang

2017-02-14

The standard treatment for aplastic anemia (AA) in young patients is a matched sibling hematopoietic stem cell transplant. Transfusion of a chronic AA patient with allogeneic bone marrow-derived mesenchymal stromal cells (BMMSCs) is currently being developed as a cell-based therapy, and the safety and efficacy of such transfusions are being continuously improved. Nevertheless, the mechanisms by which BMMSCs exert their therapeutic effects remain to be elucidated. In this study, mesenchymal stromal cells (MSCs) obtained from bone marrow donors were concentrated and intravenously injected into 15 chronic AA patients who had been refractory to prior immunosuppressive therapy. We showed that BMMSCs modulate the levels of Th1, Th2, Th17 and Treg cells, as well as their related cytokines in chronic AA patients. Furthermore, the percentages of Th1 and Th17 cells among the H-MSCs decreased significantly, while the percentage Treg cells increased. The Notch/RBP-J/FOXP3/RORγt pathway was involved in modulating the Treg/Th17 balance after MSCs were transfused in vitro. Additionally, the role played by transfused MSCs in regulating the Treg/Th17 balance via the Notch/RBP-J/FOXP3/RORγt pathway was further confirmed in an AA mouse model. In summary, in humans with chronic AA, BMMSCs regulate the Treg/Th17 balance by affecting the Notch/RBP-J/FOXP3/RORγt pathway.

Increased regulatory T cells in acute lymphoblastic leukaemia patients.

PubMed

Idris, Siti-Zuleha; Hassan, Norfarazieda; Lee, Le-Jie; Md Noor, Sabariah; Osman, Raudhawati; Abdul-Jalil, Marsitah; Nordin, Abdul-Jalil; Abdullah, Maha

2016-05-01

Regulation in adaptive immune response balances a fine line that prevents instigation of self-damage or fall into unresponsiveness permitting abnormal cell growth. Mechanisms that keep this balance in check include regulatory T cells (Tregs). Tregs consist of a small but heterogeneous population, which may be identified by the phenotype, CD3+CD4+CD25+CD127-. The role of Tregs in pathogenesis of cancers is thus far supported by evidence of increased Tregs in various cancers and may contribute to poorer prognosis. Tregs may also be important in acute leukaemias. A review of the literature on Tregs in acute leukaemias was conducted and Tregs were determined in B-cell acute lymphoblastic leukaemias (ALLs). Studies on Tregs in B-cell ALL are few and controversial. We observed a significantly increased percentage of Tregs (mean±SD, 9.72 ± 3.79% vs. 7.05 ± 1.74%; P = 0.047) in the bone marrow/peripheral blood of ALL (n = 17) compared to peripheral blood of normal controls (n = 35). A positive trend between Tregs and age (R = 0.474, P = 0.055, n = 17) implicates this factor of poor prognosis in B-cell ALL. Tregs in cancer are particularly significant in immunotherapy. The manipulation of the immune system to treat cancer has for a long time ignored regulatory mechanisms inducible or in place. In lymphoma studies, tumour-specific mechanisms that are unlike conventional methods in the induction of Tregs have been hypothesized. In addition, tumour-infiltrating Tregs may present different profiles from peripheral blood pictures. Tregs will continue to be dissected to reveal its mysteries and their impact on clinical significance.

Absence of Foxp3+ Regulatory T Cells during Allergen Provocation Does Not Exacerbate Murine Allergic Airway Inflammation

PubMed Central

Baru, Abdul Mannan; Ganesh, Venkateswaran; Krishnaswamy, Jayendra Kumar; Hesse, Christina; Untucht, Christopher; Glage, Silke; Behrens, Georg; Mayer, Christian Thomas; Puttur, Franz; Sparwasser, Tim

2012-01-01

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. PMID:23071726

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

PubMed Central

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

Regulatory T Cells Promote β-Catenin–Mediated Epithelium-to-Mesenchyme Transition During Radiation-Induced Pulmonary Fibrosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiong, Shanshan; Pan, Xiujie; Xu, Long

Purpose: Radiation-induced pulmonary fibrosis results from thoracic radiation therapy and severely limits radiation therapy approaches. CD4{sup +}CD25{sup +}FoxP3{sup +} regulatory T cells (Tregs) as well as epithelium-to-mesenchyme transition (EMT) cells are involved in pulmonary fibrosis induced by multiple factors. However, the mechanisms of Tregs and EMT cells in irradiation-induced pulmonary fibrosis remain unclear. In the present study, we investigated the influence of Tregs on EMT in radiation-induced pulmonary fibrosis. Methods and Materials: Mice thoraxes were irradiated (20 Gy), and Tregs were depleted by intraperitoneal injection of a monoclonal anti-CD25 antibody 2 hours after irradiation and every 7 days thereafter. Mice were treated onmore » days 3, 7, and 14 and 1, 3, and 6 months post irradiation. The effectiveness of Treg depletion was assayed via flow cytometry. EMT and β-catenin in lung tissues were detected by immunohistochemistry. Tregs isolated from murine spleens were cultured with mouse lung epithelial (MLE) 12 cells, and short interfering RNA (siRNA) knockdown of β-catenin in MLE 12 cells was used to explore the effects of Tregs on EMT and β-catenin via flow cytometry and Western blotting. Results: Anti-CD25 antibody treatment depleted Tregs efficiently, attenuated the process of radiation-induced pulmonary fibrosis, hindered EMT, and reduced β-catenin accumulation in lung epithelial cells in vivo. The coculture of Tregs with irradiated MLE 12 cells showed that Tregs could promote EMT in MLE 12 cells and that the effect of Tregs on EMT was partially abrogated by β-catenin knockdown in vitro. Conclusions: Tregs can promote EMT in accelerating radiation-induced pulmonary fibrosis. This process is partially mediated through β-catenin. Our study suggests a new mechanism for EMT, promoted by Tregs, that accelerates radiation-induced pulmonary fibrosis.« less

A cluster of coregulated genes determines TGF-β–induced regulatory T-cell (Treg) dysfunction in NOD mice

PubMed Central

D'Alise, Anna Morena; Ergun, Ayla; Hill, Jonathan A.; Mathis, Diane; Benoist, Christophe

2011-01-01

Foxp3+ regulatory T cells (Tregs) originate in the thymus, but the Treg phenotype can also be induced in peripheral lymphoid organs or in vitro by stimulation of conventional CD4+ T cells with IL-2 and TGF-β. There have been divergent reports on the suppressive capacity of these TGF-Treg cells. We find that TGF-Tregs derived from diabetes-prone NOD mice, although expressing normal Foxp3 levels, are uniquely defective in suppressive activity, whereas TGF-Tregs from control strains (B6g7) or ex vivo Tregs from NOD mice all function normally. Most Treg-typical transcripts were shared by NOD or B6g7 TGF-Tregs, except for a small group of differentially expressed genes, including genes relevant for suppressive activity (Lrrc32, Ctla4, and Cd73). Many of these transcripts form a coregulated cluster in a broader analysis of T-cell differentiation. The defect does not map to idd3 or idd5 regions. Whereas Treg cells from NOD mice are normal in spleen and lymph nodes, the NOD defect is observed in locations that have been tied to pathogenesis of diabetes (small intestine lamina propria and pancreatic lymph node). Thus, a genetic defect uniquely affects a specific Treg subpopulation in NOD mice, in a manner consistent with a role in determining diabetes susceptibility. PMID:21543717

A cluster of coregulated genes determines TGF-beta-induced regulatory T-cell (Treg) dysfunction in NOD mice.

PubMed

D'Alise, Anna Morena; Ergun, Ayla; Hill, Jonathan A; Mathis, Diane; Benoist, Christophe

2011-05-24

Foxp3(+) regulatory T cells (Tregs) originate in the thymus, but the Treg phenotype can also be induced in peripheral lymphoid organs or in vitro by stimulation of conventional CD4(+) T cells with IL-2 and TGF-β. There have been divergent reports on the suppressive capacity of these TGF-Treg cells. We find that TGF-Tregs derived from diabetes-prone NOD mice, although expressing normal Foxp3 levels, are uniquely defective in suppressive activity, whereas TGF-Tregs from control strains (B6g7) or ex vivo Tregs from NOD mice all function normally. Most Treg-typical transcripts were shared by NOD or B6g7 TGF-Tregs, except for a small group of differentially expressed genes, including genes relevant for suppressive activity (Lrrc32, Ctla4, and Cd73). Many of these transcripts form a coregulated cluster in a broader analysis of T-cell differentiation. The defect does not map to idd3 or idd5 regions. Whereas Treg cells from NOD mice are normal in spleen and lymph nodes, the NOD defect is observed in locations that have been tied to pathogenesis of diabetes (small intestine lamina propria and pancreatic lymph node). Thus, a genetic defect uniquely affects a specific Treg subpopulation in NOD mice, in a manner consistent with a role in determining diabetes susceptibility.

The Tregs' world according to GARP.

PubMed

Battaglia, Manuela; Roncarolo, Maria Grazia

2009-12-01

Naturally occurring CD4+CD25(high) regulatory T cells (nTreg) are essential for maintaining tolerance. FOXP3 has been established as a molecular marker of nTreg; however, FOXP3 cannot be used as a reliable marker for bona fide human nTreg since effector T cells also up-regulate FOXP3 expression upon activation. Despite the important function of nTreg, the underlying molecular mechanisms of nTreg-mediated suppression are far from defined. Previous studies have demonstrated that the TGF-beta latency-associated peptide (LAP) is expressed on the surface of nTreg, and that immunosuppression can be mediated by membrane TGF-beta; however, it remains unknown how LAP is bound to nTreg and what is the functional significance of its selective expression on activated nTreg. The nTreg's world may now change according to GARP, an orphan toll-like receptor composed of leucine-rich repeats. In this issue of the European Journal of Immunology, a study provides further demonstration that GARP is selectively expressed only in activated human nTreg and nTreg cell clones but not in activated effector T cells, confirming GARP as a bona fide nTreg marker. In addition, GARP binds directly to LAP; yet, GARP over-expression is insufficient to induce modification of latent TGF-beta into active TGF-beta further clarifying its role in nTreg-mediated suppression.

Improved Anti-Treg Vaccination Targeting Foxp3 Efficiently Decreases Regulatory T Cells in Mice.

PubMed

Mousavi Niri, Neda; Memarnejadian, Arash; Pilehvar-Soltanahmadi, Younes; Agha Sadeghi, Mohammadreza; Mahdavi, Mehdi; Kheshtchin, Nasim; Arab, Samaneh; Namdar, Afshin; Jadidi, Farhad; Zarghami, Nosratollah; Hajati, Jamshid

2016-09-01

The critical role of regulatory T (Treg) cells in dampening immune responses against tumor cells is apparent. Therefore, several methods have been introduced for eliminating Treg. Among them, inducing immune responses against Treg cells expressing Foxp3 transcription factor is a hopeful approach to decrease the frequency of Tregs. In current study, we used the chimeric FoxP3-Fc(IgG) fusion construct/protein to effectively stimulate the immune responses against Treg cells. Previously constructed FoxP3-Fc(IgG) DNA vaccine and its protein counterpart were injected into C57BL/6 mice in a prime/boost regimen. After 2 weeks, the mice were killed to measure the frequency of Tregs in their spleens, as well as analyze their specific cytokine production, T-cell proliferation, and CD8 T-cell cytotoxicity against FoxP3 protein. FACS analysis of FoxP3 CD4 cells in splenocytes revealed the efficiency of FoxP3 DNA-prime protein-boost strategy to decrease the Treg cells and further showed considerable superiority of Fc(IgG) fusion strategy. This significant reduction in Treg frequency was also concomitant with higher FoxP3-specific CTL and Th1 responses in FoxP3-Fc vaccinated animals. Prime/boost vaccination against FoxP3 in addition to enhanced antigen presentation by means of Fc fusion strategy could be successfully considered for Treg depletion studies. Validity of this approach should be experimentally tested in preclinical tumor models.

In vitro generated Th17 cells support the expansion and phenotypic stability of CD4(+)Foxp3(+) regulatory T cells in vivo.

PubMed

Zhou, Qiong; Hu, Ya; Howard, O M Zack; Oppenheim, Joost J; Chen, Xin

2014-01-01

CD4(+) T cells stimulate immune responses through distinct patterns of cytokine produced by Th1, Th2 or Th17 cells, or inhibit immune responses through Foxp3-expressing regulatory T cells (Tregs). Paradoxically, effector T cells were recently shown to activate Tregs, however, it remains unclear which Th subset is responsible for this effect. In this study, we found that Th17 cells expressed the highest levels of TNF among in vitro generated Th subsets, and most potently promoted expansion and stabilized Foxp3 expression by Tregs when co-transferred into Rag1(-/-) mice. Both TNF and IL-2 produced by Th17 cells contributed to this effect. The stimulatory effect of Th17 cells on Tregs was largely abolished when co-transferred with TNFR2-deficient Tregs. Furthermore, Tregs deficient in TNFR2 also supported a much lower production of IL-17A and TNF expression by co-transferred Th17 cells. Thus, our data indicate that the TNF-TNFR2 pathway plays a crucial role in the reciprocal stimulatory effect of Th17 cells and Tregs. This bidirectional interaction should be taken into account when designing therapy targeting Th17 cells, Tregs, TNF and TNFR2. Copyright © 2013 Elsevier Ltd. All rights reserved.

Regulatory T cells are recruited in the infarcted mouse myocardium and may modulate fibroblast phenotype and function

PubMed Central

Saxena, Amit; Dobaczewski, Marcin; Rai, Vikrant; Haque, Zaffar; Chen, Wei; Li, Na

2014-01-01

Regulatory T cells (Tregs) play a pivotal role in suppressing immune responses regulating behavior and gene expression in effector T cells, macrophages, and dendritic cells. Tregs infiltrate the infarcted myocardium; however, their role the inflammatory and reparative response after myocardial infarction remains poorly understood. We used FoxP3EGFP reporter mice to study Treg trafficking in the infarcted heart and examined the effects of Treg depletion on postinfarction remodeling using an anti-CD25 antibody. Moreover, we investigated the in vitro effects of Tregs on cardiac fibroblast phenotype and function. Low numbers of Tregs infiltrated the infarcted myocardium after 24–72 h of reperfusion. Treg depletion had no significant effects on cardiac dysfunction and scar size after reperfused myocardial infarction but accelerated ventricular dilation and accentuated apical remodeling. Enhanced myocardial dilation in Treg-depleted animals was associated with increased expression of chemokine (C-C motif) ligand 2 and accentuated macrophage infiltration. In vitro, Tregs modulated the cardiac fibroblast phenotype, reducing expression of α-smooth muscle actin, decreasing expression of matrix metalloproteinase-3, and attenuating contraction of fibroblast-populated collagen pads. Our findings suggest that endogenous Tregs have modest effects on the inflammatory and reparative response after myocardial infarction. However, the anti-inflammatory and matrix-preserving properties of Tregs may suggest a role for Treg-based cell therapy in the attenuation of adverse postinfarction remodeling. PMID:25128167

Functional defect in regulatory T cells in myasthenia gravis

PubMed Central

Thiruppathi, Muthusamy; Rowin, Julie; Jiang, Qin Li; Sheng, Jian Rong; Prabhakar, Bellur S.; Meriggioli, Matthew N.

2012-01-01

Forkhead box P3 (FOXP3)+ is a transcription factor necessary for the function of regulatory T cells (Treg cells). Treg cells maintain immune homeostasis and self-tolerance, and play an important role in the prevention of autoimmune disease. Here, we discuss the role of Treg cells in the pathogenesis of myasthenia gravis (MG) and review evidence indicating that a significant defect in Treg cell in vitro suppressive function exists in MG patients, without an alteration in circulating frequency. This functional defect is associated with a reduced expression of key functional molecules such as FOXP3 on isolated Treg cells and appears to be more pronounced in immunosuppression-naive MG patients. In vitro administration of granulocyte-macrophage colony-stimulating factor (GM-CSF) enhanced the suppressive function of Treg cells and up-regulated FOXP3 expression. These findings indicate a clinically relevant Treg cell–intrinsic defect in immune regulation in MG that may reveal a novel therapeutic target. PMID:23252899

Effect of chorioamnionitis on regulatory T cells in moderate/late preterm neonates.

PubMed

Rueda, Cesar M; Wells, Casey B; Gisslen, Tate; Jobe, Alan H; Kallapur, Suhas G; Chougnet, Claire A

2015-01-01

Regulatory T-cells (Treg) have a protective role for the control of immune activation and tissue damage. The effects of chorioamnionitis (chorio) on Treg in moderate/late preterm newborns are not known. We hypothesized that infants exposed to chorio would have decreased Treg frequency and/or function. We isolated mononuclear cells from adult peripheral blood and cord blood from term and moderate/late preterm infants who were classified for severity of chorio exposure. Mononuclear cells were analyzed by flow cytometry for Treg frequency and phenotype. Treg suppression of activation of conventional T-cells (Tcon) was also quantified. Treg frequencies were similar in all groups of neonates, but lower than that found in adults. Newborn Treg had a naïve phenotype, with decreased levels of CD45RO, HLA-DR, CD39 and TIGIT compared to adult Treg and chorio did not affect the phenotype. Treg from preterm newborns exposed to severe chorio had higher expression of Ki67 compared to the other groups. Treg from preterm newborns were less suppressive than Treg from adults or term, and the level of suppression was reduced with severe chorio. Relative to term, Treg frequency and phenotype were not affected by prematurity and chorio but their functionality was decreased. Lower Treg activity may contribute to inflammation in newborns that is often associated with chorioamnionitis. Copyright © 2014 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Liver injury in acute hepatitis A is associated with decreased frequency of regulatory T cells caused by Fas-mediated apoptosis.

PubMed

Choi, Yoon Seok; Lee, Jeewon; Lee, Hyun Woong; Chang, Dong-Yeop; Sung, Pil Soo; Jung, Min Kyung; Park, Jun Yong; Kim, Ja Kyung; Lee, Jung Il; Park, Hana; Cheong, Jae Youn; Suh, Kyung-Suk; Kim, Hyung Joon; Lee, June Sung; Kim, Kyung-Ah; Shin, Eui-Cheol

2015-08-01

Foxp3(+)CD4(+)CD25(+) regulatory T cells (Tregs) control immune responses, but their role in acute viral hepatitis remains elusive. Herein, we investigated alteration in the peripheral blood Treg population during acute hepatitis A (AHA) and its implication in the immune-mediated liver injury. The study included 71 patients with AHA, and peripheral blood mononuclear cells (PBMCs) were isolated. The suppressive activity of Treg population was determined by assessing anti-CD3/CD28-stimulated proliferation of Treg-depleted and reconstituted PBMCs. Treg cell frequency, phenotype and apoptosis in PBMCs were analysed by flow cytometry. The frequency of circulating Tregs was reduced during AHA. Moreover, the suppressive activity of the total Treg pool in the peripheral blood was attenuated during AHA. Treg frequency and suppressive activity of the Treg population inversely correlated with the serum alanine aminotransferase level. Fas was overexpressed on Tregs during AHA, suggesting their susceptibility to Fas-induced apoptosis. Indeed, increased apoptotic death was observed in Tregs of patients with AHA compared with healthy controls. In addition, agonistic anti-Fas treatment further increased apoptotic death of Tregs from patients with AHA. The decreased Treg frequency and Fas overexpression on Tregs were not observed in other acute liver diseases such as acute hepatitis B, acute hepatitis C and toxic/drug-induced hepatitis. The size of the Treg pool was contracted during AHA, resulting from apoptosis of Tregs induced by a Fas-mediated mechanism. Decrease in Treg numbers led to reduced suppressive activity of the Treg pool and consequently resulted in severe liver injury during AHA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Thymic Stromal Lymphopoietin Attenuates the Development of Atherosclerosis in ApoE−/− Mice

PubMed Central

Yu, Kunwu; Zhu, Pengfei; Dong, Qian; Zhong, Yucheng; Zhu, Zhengfeng; Lin, Yingzhong; Huang, Ying; Meng, Kai; Ji, Qingwei; Yi, Guiwen; Zhang, Wei; Wu, Bangwei; Mao, Yi; Cheng, Peng; Zhao, Xiaoqi; Mao, Xiaobo; Zeng, Qiutang

2013-01-01

Background Thymic stromal lymphopoietin (TSLP) is a cytokine with multiple effects on the body. For one thing, TSLP induces Th2 immunoreaction and facilitates allergic reaction; for another, it promotes the differentiation of naturally occurring CD4+CD25+Foxp3+ regulatory T cells (nTregs) and maintains immune tolerance. However, the exact role of TSLP in atherosclerosis remains unknown. Methods and Results In vitro, we examined the phenotype of TSLP‐conditioned bone marrow dendritic cells (TSLP‐DCs) of apolipoprotein E–deficient (ApoE−/−) mice and their capacity to induce the differentiation of Tregs. Our results indicated that TSLP‐DCs obtained the characteristics of tolerogenic dendritic cells and increased a generation of CD4+ latency‐associated peptide (LAP)+ Tregs and nTregs when cocultured with naive T cells. In addition, the functional relevance of TSLP and TSLP‐DCs in the development of atherosclerosis was also determined. Interestingly, we found that TSLP was almost absent in cardiovascular tissue of ApoE−/− mice, and TSLP administration increased the levels of antioxidized low‐density lipoprotein IgM and IgG1, but decreased the levels of IgG2a in plasma. Furthermore, mice treated with TSLP and TSLP‐DCs developed significantly fewer (32.6% and 28.2%, respectively) atherosclerotic plaques in the aortic root compared with controls, along with increased numbers of CD4+LAP+ Tregs and nTregs in the spleen and decreased inflammation in the aorta, which could be abrogated by anti‐TGF‐β antibody. Conclusions Our results revealed a protective role for TSLP in atherosclerosis that is possibly mediated by reestablishing a tolerogenic immune response, which may represent a novel possibility for treatment or prevention of atherosclerosis. PMID:23985377

Characterization of blood dendritic and regulatory T cells in asymptomatic adults with sub-microscopic Plasmodium falciparum or Plasmodium vivax infection.

PubMed

Kho, Steven; Marfurt, Jutta; Handayuni, Irene; Pava, Zuleima; Noviyanti, Rintis; Kusuma, Andreas; Piera, Kim A; Burdam, Faustina H; Kenangalem, Enny; Lampah, Daniel A; Engwerda, Christian R; Poespoprodjo, Jeanne R; Price, Ric N; Anstey, Nicholas M; Minigo, Gabriela; Woodberry, Tonia

2016-06-21

Plasmodium falciparum and Plasmodium vivax infections compromise dendritic cell (DC) function and expand regulatory T (Treg) cells in both clinical disease (malaria) and experimental human sub-microscopic infection. Conversely, in asymptomatic microscopy-positive (patent) P. falciparum or P. vivax infection in endemic areas, blood DC increase or retain HLA-DR expression and Treg cells exhibit reduced activation, suggesting that DC and Treg cells contribute to the control of patent asymptomatic infection. The effect of sub-microscopic (sub-patent) asymptomatic Plasmodium infection on DC and Treg cells in malaria-endemic area residents remains unclear. In a cross-sectional household survey conducted in Papua, Indonesia, 162 asymptomatic adults were prospectively evaluated for DC and Treg cells using field-based flow cytometry. Of these, 161 individuals (99 %) were assessed retrospectively by polymerase chain reaction (PCR), 19 of whom had sub-microscopic infection with P. falciparum and 15 with sub-microscopic P. vivax infection. Flow cytometric data were re-analysed after re-grouping asymptomatic individuals according to PCR results into negative controls, sub-microscopic and microscopic parasitaemia to examine DC and Treg cell phenotype in sub-microscopic infection. Asymptomatic adults with sub-microscopic P. falciparum or P. vivax infection had DC HLA-DR expression and Treg cell activation comparable to PCR-negative controls. Sub-microscopic P. falciparum infection was associated with lower peripheral CD4(+) T cells and lymphocytes, however sub-microscopic Plasmodium infection had no apparent effect on DC sub-set number or Treg cell frequency. In contrast to the impairment of DC maturation/function and the activation of Treg cells seen with sub-microscopic parasitaemia in primary experimental human Plasmodium infection, no phenotypic evidence of dysregulation of DC and Treg cells was observed in asymptomatic sub-microscopic Plasmodium infection in Indonesian adults. This is consistent with DC and Treg cells retaining their functional capacity in sub-microscopic asymptomatic infection with P. falciparum or P. vivax in malaria-endemic areas.

CD11c-Expressing Cells Affect Regulatory T Cell Behavior in the Meninges during Central Nervous System Infection.

PubMed

O'Brien, Carleigh A; Overall, Christopher; Konradt, Christoph; O'Hara Hall, Aisling C; Hayes, Nikolas W; Wagage, Sagie; John, Beena; Christian, David A; Hunter, Christopher A; Harris, Tajie H

2017-05-15

Regulatory T cells (Tregs) play an important role in the CNS during multiple infections, as well as autoimmune inflammation, but the behavior of this cell type in the CNS has not been explored. In mice, infection with Toxoplasma gondii leads to a Th1-polarized parasite-specific effector T cell response in the brain. Similarly, Tregs in the CNS during T. gondii infection are Th1 polarized, as exemplified by their T-bet, CXCR3, and IFN-γ expression. Unlike effector CD4 + T cells, an MHC class II tetramer reagent specific for T. gondii did not recognize Tregs isolated from the CNS. Likewise, TCR sequencing revealed minimal overlap in TCR sequence between effector T cells and Tregs in the CNS. Whereas effector T cells are found in the brain parenchyma where parasites are present, Tregs were restricted to the meninges and perivascular spaces. The use of intravital imaging revealed that activated CD4 + T cells within the meninges were highly migratory, whereas Tregs moved more slowly and were found in close association with CD11c + cells. To test whether the behavior of Tregs in the meninges is influenced by interactions with CD11c + cells, mice were treated with anti-LFA-1 Abs to reduce the number of CD11c + cells in this space. The anti-LFA-1 treatment led to fewer contacts between Tregs and the remaining CD11c + cells and increased the speed of Treg migration. These data suggest that Tregs are anatomically restricted within the CNS, and their interaction with CD11c + populations regulates their local behavior during T. gondii infection. Copyright © 2017 by The American Association of Immunologists, Inc.

Allogeneic Mature Human Dendritic Cells Generate Superior Alloreactive Regulatory T Cells in the Presence of IL-15.

PubMed

Litjens, Nicolle H R; Boer, Karin; Zuijderwijk, Joke M; Klepper, Mariska; Peeters, Annemiek M A; Prens, Errol P; Verschoor, Wenda; Kraaijeveld, Rens; Ozgur, Zeliha; van den Hout-van Vroonhoven, Mirjam C; van IJcken, Wilfred F J; Baan, Carla C; Betjes, Michiel G H

2015-06-01

Expansion of Ag-specific naturally occurring regulatory T cells (nTregs) is required to obtain sufficient numbers of cells for cellular immunotherapy. In this study, different allogeneic stimuli were studied for their capacity to generate functional alloantigen-specific nTregs. A highly enriched nTreg fraction (CD4(+)CD25(bright)CD127(-) T cells) was alloantigen-specific expanded using HLA-mismatched immature, mature monocyte-derived dendritic cells (moDCs), or PBMCs. The allogeneic mature moDC-expanded nTregs were fully characterized by analysis of the demethylation status within the Treg-specific demethylation region of the FOXP3 gene and the expression of both protein and mRNA of FOXP3, HELIOS, CTLA4, and cytokines. In addition, the Ag-specific suppressive capacity of these expanded nTregs was tested. Allogeneic mature moDCs and skin-derived DCs were superior in inducing nTreg expansion compared with immature moDCs or PBMCs in an HLA-DR- and CD80/CD86-dependent way. Remarkably, the presence of exogenous IL-15 without IL-2 could facilitate optimal mature moDC-induced nTreg expansion. Allogeneic mature moDC-expanded nTregs were at low ratios (<1:320), potent suppressors of alloantigen-induced proliferation without significant suppression of completely HLA-mismatched, Ag-induced proliferation. Mature moDC-expanded nTregs were highly demethylated at the Treg-specific demethylation region within the FOXP3 gene and highly expressed of FOXP3, HELIOS, and CTLA4. A minority of the expanded nTregs produced IL-10, IL-2, IFN-γ, and TNF-α, but few IL-17-producing nTregs were found. Next-generation sequencing of mRNA of moDC-expanded nTregs revealed a strong induction of Treg-associated mRNAs. Human allogeneic mature moDCs are highly efficient stimulator cells, in the presence of exogenous IL-15, for expansion of stable alloantigen-specific nTregs with superior suppressive function. Copyright © 2015 by The American Association of Immunologists, Inc.

Control of regulatory T cell lineage commitment and maintenance.

PubMed

Josefowicz, Steven Z; Rudensky, Alexander

2009-05-01

Foxp3-expressing regulatory T (Treg) cells suppress pathology mediated by immune responses against self and foreign antigens and commensal microorganisms. Sustained expression of the transcription factor Foxp3, a key distinguishing feature of Treg cells, is required for their differentiation and suppressor function. In addition, Foxp3 expression prevents deviation of Treg cells into effector T cell lineages and confers dependence of Treg cell survival and expansion on growth factors, foremost interleukin-2, provided by activated effector T cells. In this review we discuss Treg cell differentiation and maintenance with a particular emphasis on molecular regulation of Foxp3 expression, arguably a key to mechanistic understanding of biology of regulatory T cells.

Partial CD25 Antagonism Enables Dominance of Antigen-Inducible CD25high FOXP3+ Regulatory T Cells As a Basis for a Regulatory T Cell-Based Adoptive Immunotherapy

PubMed Central

Wilkinson, Daniel S.; Ghosh, Debjani; Nickle, Rebecca A.; Moorman, Cody D.; Mannie, Mark D.

2017-01-01

FOXP3+ regulatory T cells (Tregs) represent a promising platform for effective adoptive immunotherapy of chronic inflammatory disease, including autoimmune diseases such as multiple sclerosis. Successful Treg immunotherapy however requires new technologies to enable long-term expansion of stable, antigen-specific FOXP3+ Tregs in cell culture. Antigen-specific activation of naïve T cells in the presence of TGF-β elicits the initial differentiation of the FOXP3+ lineage, but these Treg lines lack phenotypic stability and rapidly transition to a conventional T cell (Tcon) phenotype during in vitro propagation. Because Tregs and Tcons differentially express CD25, we hypothesized that anti-CD25 monoclonal antibodies (mAbs) would only partially block IL-2 signaling in CD25high FOXP3+ Tregs while completely blocking IL-2 responses of CD25low-intermediate Tcons to enable preferential outgrowth of Tregs during in vitro propagation. Indeed, murine TGF-β-induced MOG-specific Treg lines from 2D2 transgenic mice that were maintained in IL-2 with the anti-CD25 PC61 mAb rapidly acquired and indefinitely maintained a FOXP3high phenotype during long-term in vitro propagation (>90% FOXP3+ Tregs), whereas parallel cultures lacking PC61 rapidly lost FOXP3. These results pertained to TGF-β-inducible “iTregs” because Tregs from 2D2-FIG Rag1−/− mice, which lack thymic or natural Tregs, were stabilized by continuous culture in IL-2 and PC61. MOG-specific and polyclonal Tregs upregulated the Treg-associated markers Neuropilin-1 (NRP1) and Helios (IKZF2). Just as PC61 stabilized FOXP3+ Tregs during expansion in IL-2, TGF-β fully stabilized FOXP3+ Tregs during cellular activation in the presence of dendritic cells and antigen/mitogen. Adoptive transfer of blastogenic CD25high FOXP3+ Tregs from MOG35-55-specific 2D2 TCR transgenic mice suppressed experimental autoimmune encephalomyelitis in pretreatment and therapeutic protocols. In conclusion, low IL-2 concentrations coupled with high PC61 concentrations constrained IL-2 signaling to a low-intensity range that enabled dominant stable outgrowth of suppressive CD25high FOXP3+ Tregs. The ability to indefinitely expand stable Treg lines will provide insight into FOXP3+ Treg physiology and will be foundational for Treg-based immunotherapy. PMID:29312311

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

PubMed

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 contributor to disease pathogenesis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Partial regulatory T cell depletion prior to acute feline immunodeficiency virus infection does not alter disease pathogenesis.

PubMed

Mikkelsen, S Rochelle; Long, Julie M; Zhang, Lin; Galemore, Erin R; VandeWoude, Sue; Dean, Gregg A

2011-02-25

Feline immunodeficiency virus (FIV) infection in cats follows a disease course similar to HIV-1, including a short acute phase characterized by high viremia, and a prolonged asymptomatic phase characterized by low viremia and generalized immune dysfunction. CD4(+)CD25(hi)FoxP3(+) immunosuppressive regulatory T (Treg) cells have been implicated as a possible cause of immune dysfunction during FIV and HIV-1 infection, as they are capable of modulating virus-specific and inflammatory immune responses. Additionally, the immunosuppressive capacity of feline Treg cells has been shown to be increased during FIV infection. We have previously shown that transient in vivo Treg cell depletion during asymptomatic FIV infection reveals FIV-specific immune responses suppressed by Treg cells. In this study, we sought to determine the immunological influence of Treg cells during acute FIV infection. We asked whether Treg cell depletion prior to infection with the highly pathogenic molecular clone FIV-C36 in cats could alter FIV pathogenesis. We report here that partial Treg cell depletion prior to FIV infection does not significantly change provirus, viremia, or CD4(+) T cell levels in blood and lymphoid tissues during the acute phase of disease. The effects of anti-CD25 mAb treatment are truncated in cats acutely infected with FIV-C36 as compared to chronically infected cats or FIV-naïve cats, as Treg cell levels were heightened in all treatment groups included in the study within two weeks post-FIV infection. Our findings suggest that the influence of Treg cell suppression during FIV pathogenesis is most prominent after Treg cells are activated in the environment of established FIV infection.

Signal peptide cleavage is essential for surface expression of a regulatory T cell surface protein, leucine rich repeat containing 32 (LRRC32)

PubMed Central

2011-01-01

Background Elevated numbers of regulatory T cells (Tregs) have been implicated in certain cancers. Depletion of Tregs has been shown to increase anti-tumor immunity. Tregs also play a critical role in the suppression of autoimmune responses. The study of Tregs has been hampered by a lack of adequate surface markers. Leucine Rich Repeat Containing 32 (LRRC32), also known as Glycoprotein A Repetitions Predominant (GARP), has been postulated as a novel surface marker of activated Tregs. However, there is limited information regarding the processing of LRRC32 or the regulatory phenotype and functional activity of Tregs expressing LRRC32. Results Using naturally-occurring freshly isolated Tregs, we demonstrate that low levels of LRRC32 are present intracellularly prior to activation and that freshly isolated LRRC32+ Tregs are distinct from LRRC32- Tregs with respect to the expression of surface CD62L. Using LRRC32 transfectants of HEK cells, we demonstrate that the N-terminus of LRRC32 is cleaved prior to expression of the protein at the cell surface. Furthermore, we demonstrate using a construct containing a deleted putative signal peptide region that the presence of a signal peptide region is critical to cell surface expression of LRRC32. Finally, mixed lymphocyte assays demonstrate that LRRC32+ Tregs are more potent suppressors than LRRC32- Tregs. Conclusions A cleaved signal peptide site in LRRC32 is necessary for surface localization of native LRRC32 following activation of naturally-occurring freshly-isolated regulatory T cells. LRRC32 expression appears to alter the surface expression of activation markers of T cells such as CD62L. LRRC32 surface expression may be useful as a marker that selects for more potent Treg populations. In summary, understanding the processing and expression of LRRC32 may provide insight into the mechanism of action of Tregs and the refinement of immunotherapeutic strategies aimed at targeting these cells. PMID:21615933

Type 2 innate lymphoid cell suppression by regulatory T cells attenuates airway hyperreactivity and requires inducible T-cell costimulator-inducible T-cell costimulator ligand interaction.

PubMed

Rigas, Diamanda; Lewis, Gavin; Aron, Jennifer L; Wang, Bowen; Banie, Homayon; Sankaranarayanan, Ishwarya; Galle-Treger, Lauriane; Maazi, Hadi; Lo, Richard; Freeman, Gordon J; Sharpe, Arlene H; Soroosh, Pejman; Akbari, Omid

2017-05-01

Atopic diseases, including asthma, exacerbate type 2 immune responses and involve a number of immune cell types, including regulatory T (Treg) cells and the emerging type 2 innate lymphoid cells (ILC2s). Although ILC2s are potent producers of type 2 cytokines, the regulation of ILC2 activation and function is not well understood. In the present study, for the first time, we evaluate how Treg cells interact with pulmonary ILC2s and control their function. ILC2s and Treg cells were evaluated by using in vitro suppression assays, cell-contact assays, and gene expression panels. Also, human ILC2s and Treg cells were adoptively transferred into NOD SCID γC-deficient mice, which were given isotype or anti-inducible T-cell costimulator ligand (ICOSL) antibodies and then challenged with IL-33 and assessed for airway hyperreactivity. We show that induced Treg cells, but not natural Treg cells, effectively suppress the production of the ILC2-driven proinflammatory cytokines IL-5 and IL-13 both in vitro and in vivo. Mechanistically, our data reveal the necessity of inducible T-cell costimulator (ICOS)-ICOS ligand cell contact for Treg cell-mediated ILC2 suppression alongside the suppressive cytokines TGF-β and IL-10. Using a translational approach, we then demonstrate that human induced Treg cells suppress syngeneic human ILC2s through ICOSL to control airway inflammation in a humanized ILC2 mouse model. These findings suggest that peripheral expansion of induced Treg cells can serve as a promising therapeutic target against ILC2-dependent asthma. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Immuno-Navigator, a batch-corrected coexpression database, reveals cell type-specific gene networks in the immune system

PubMed Central

Vandenbon, Alexis; Dinh, Viet H.; Mikami, Norihisa; Kitagawa, Yohko; Teraguchi, Shunsuke; Ohkura, Naganari; Sakaguchi, Shimon

2016-01-01

High-throughput gene expression data are one of the primary resources for exploring complex intracellular dynamics in modern biology. The integration of large amounts of public data may allow us to examine general dynamical relationships between regulators and target genes. However, obstacles for such analyses are study-specific biases or batch effects in the original data. Here we present Immuno-Navigator, a batch-corrected gene expression and coexpression database for 24 cell types of the mouse immune system. We systematically removed batch effects from the underlying gene expression data and showed that this removal considerably improved the consistency between inferred correlations and prior knowledge. The data revealed widespread cell type-specific correlation of expression. Integrated analysis tools allow users to use this correlation of expression for the generation of hypotheses about biological networks and candidate regulators in specific cell types. We show several applications of Immuno-Navigator as examples. In one application we successfully predicted known regulators of importance in naturally occurring Treg cells from their expression correlation with a set of Treg-specific genes. For one high-scoring gene, integrin β8 (Itgb8), we confirmed an association between Itgb8 expression in forkhead box P3 (Foxp3)-positive T cells and Treg-specific epigenetic remodeling. Our results also suggest that the regulation of Treg-specific genes within Treg cells is relatively independent of Foxp3 expression, supporting recent results pointing to a Foxp3-independent component in the development of Treg cells. PMID:27078110

Zoledronic acid inhibits NFAT and IL-2 signaling pathways in regulatory T cells and diminishes their suppressive function in patients with metastatic cancer

PubMed Central

Murray, Shannon; Witt, Kristina; Seitz, Christina; Wallerius, Majken; Xie, Hanjing; Ullén, Anders; Harmenberg, Ulrika; Lidbrink, Elisabet; Rolny, Charlotte; Andersson, John

2017-01-01

ABSTRACT Regulatory T cells (Treg) suppress anti-tumor immune responses and their infiltration in the tumor microenvironment is associated with inferior prognosis in cancer patients. Thus, in order to enhance anti-tumor immune responses, selective depletion of Treg is highly desired. We found that treatment with zoledronic acid (ZA) resulted in a selective decrease in the frequency of Treg that was associated with a significant increase in proliferation of T cells and natural killer (NK) cells in peripheral blood of patients with metastatic cancer. In vitro, genome-wide transcriptomic analysis revealed alterations in calcium signaling pathways in Treg following treatment with ZA. Furthermore, co-localization of the nuclear factor of activated T cells (NFAT) and forkhead box P3 (FOXP3) was significantly reduced in Treg upon ZA-treatment. Consequently, reduced expression levels of CD25, STAT5 and TGFβ were observed. Functionally, ZA-treated Treg had reduced capacity to suppress T and NK cell proliferation and anti-tumor responses compared with untreated Treg in vitro. Treatment with ZA to selectively inhibit essential signaling pathways in Treg resulting in reduced capacity to suppress effector T and NK cell responses represents a novel approach to inhibit Treg activity in patients with cancer. PMID:28920001

Chimeric Antigen Receptor-Redirected Regulatory T Cells Suppress Experimental Allergic Airway Inflammation, a Model of Asthma.

PubMed

Skuljec, Jelena; Chmielewski, Markus; Happle, Christine; Habener, Anika; Busse, Mandy; Abken, Hinrich; Hansen, Gesine

2017-01-01

Cellular therapy with chimeric antigen receptor (CAR)-redirected cytotoxic T cells has shown impressive efficacy in the treatment of hematologic malignancies. We explored a regulatory T cell (Treg)-based therapy in the treatment of allergic airway inflammation, a model for asthma, which is characterized by an airway hyper-reactivity (AHR) and a chronic, T helper-2 (Th2) cell-dominated immune response to allergen. To restore the immune balance in the lung, we redirected Tregs by a CAR toward lung epithelia in mice upon experimentally induced allergic asthma, closely mimicking the clinical situation. Adoptively transferred CAR Tregs accumulated in the lung and in tracheobronchial lymph nodes, reduced AHR and diminished eosinophilic airway inflammation, indicated by lower cell numbers in the bronchoalveolar lavage fluid and decreased cell infiltrates in the lung. CAR Treg cells furthermore prevented excessive pulmonary mucus production as well as increase in allergen-specific IgE and Th2 cytokine levels in exposed animals. CAR Tregs were more efficient in controlling asthma than non-modified Tregs, indicating the pivotal role of specific Treg cell activation in the affected organ. Data demonstrate that lung targeting CAR Treg cells ameliorate key features of experimental airway inflammation, paving the way for cell therapy of severe allergic asthma.

Dendritic Cells Regulate Treg-Th17 Axis in Obstructive Phase of Bile Duct Injury in Murine Biliary Atresia

PubMed Central

Tang, Shao-tao; Wang, Xin-xing; Cao, Guo-qing; Li, Shuai; Lei, Hai-yan; Zhang, Xi

2015-01-01

Several cell types are considered to be effector cells in bile duct injury in rhesus rotavirus (RRV)-induced experimental biliary atresia (BA). Here, we identified an increased T helper 17 (Th17) cell population in a BA mode. By depleting the Th17 cells, the BA symptoms (onset of jaundice, acholic stools and retarded growth) were attenuated and the survival rate was improved. Furthermore, we found that in mice with BA, the percentage of CD4+CD25highFoxp3+ T regulatory (Treg) cells decreased along with the increased percentage of Th17 cells. However, the absolute numbers of Treg and Th17 cells were both increased in liver of RRV-injected mice compared to saline-injected mice. The proportion of Th17 cells at 7 days post-infection was decreased if Treg cells isolated from normal adult mice, but not Treg cells from the livers of mice with BA, were intraperitoneally transferred on day 5 of life. In vitro experiments also showed that Treg cells from mice with BA had a diminished suppressive effect on Th17 cell generation. To determine the mechanisms, we investigated the production of cytokines in the liver. The level of IL-6, which has been shown to be abundantly secreted by activated dendritic cells (DCs), was remarkably elevated. Importantly, in a Treg/Th17 cell suppression assay, IL-6 was demonstrated to paralyze the Treg cells’ suppressive effect on Th17 cells and eventually the unrestrained increase of Th17 cells contributed to bile duct injury. In conclusion, the DC-regulated Treg-Th17 axis, probably in conjunction with other effector T cells, aggravates progressive inflammatory injury at the time of ductal obstruction. PMID:26325187

Critical role of IFN-gamma in CFA-mediated protection of NOD mice from diabetes development.

PubMed

Mori, Yoshiko; Kodaka, Tetsuro; Kato, Takako; Kanagawa, Edith M; Kanagawa, Osami

2009-11-01

IFN-gamma signaling-deficient non-obese diabetic (NOD) mice develop diabetes with similar kinetics to those of wild-type NOD mice. However, the immunization of IFN-gamma signaling-deficient NOD mice with CFA failed to induce long-term protection, whereas wild-type NOD mice receiving CFA remained diabetes-free. CFA also failed to protect IFN-gamma receptor-deficient (IFN-gammaR(-/-)) NOD mice from the autoimmune rejection of transplanted islets, as it does in diabetic NOD mice, and from disease transfer by spleen cells from diabetic NOD mice. These data clearly show that the pro-inflammatory cytokine IFN-gamma is necessary for the CFA-mediated protection of NOD mice from diabetes. There is no difference in the T(h)1/T(h)17 balance between IFN-gammaR(-/-) NOD and wild-type NOD mice. There is also no difference in the total numbers and percentages of regulatory T (Treg) cells in the lymph node CD4(+) T-cell populations between IFN-gammaR(-/-) NOD and wild-type NOD mice. However, pathogenic T cells lacking IFN-gammaR are resistant to the suppressive effect of Treg cells, both in vivo and in vitro. Therefore, it is likely that CFA-mediated protection against diabetes development depends on a change in the balance between Treg cells and pathogenic T cells, and IFN-gamma signaling seems to control the susceptibility of pathogenic T cells to the inhibitory activity of Treg cells.

Increased IL-35 producing Tregs and CD19+IL-35+ cells are associated with disease progression in leprosy patients.

PubMed

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

2017-03-01

The clinical forms of leprosy consist of a spectrum that reflects the host's immune response to the M. leprae; it provides an ideal model to study the host pathogen interaction and immunological dysregulation in humans. IL-10 and TGF-β producing Tregs are high in leprosy patients and responsible for immune suppression and M. leprae specific T cells anergy. In leprosy, involvement of IL-35 producing Tregs and Bregs remain unstudied. To study the role of IL-35 producing Tregs and Bregs in the human leprosy. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA) for 48h. Intracellular cytokine IL-35 was evaluated in CD4 + CD25 + Tregs, CD19 + cells by FACS. Expression of PD-1 on CD4 + CD25 + Tregs, CD19 + cells and its ligand (PD-L1) on B cells, CD11c cells were evaluated by flow cytometry (FACS). Serum IL-35 level was estimated by ELISA. The frequency of IL-35 producing Tregs and Bregs cells were found to be high in leprosy patients (p<0.0001) as compared to healthy controls. These cells produced suppressive cytokine IL-35 which showed positive correlation with bacteriological index (BI) and TGF-β producing Tregs, indicating its suppressive nature. We found higher expression of PD-1 on Tregs, B cell and its ligand (PD-L1) on antigen presenting cells in leprosy patients. This study point out a shift in our understanding of the immunological features that mediate and regulate the immune suppression and the disease progression in leprosy patients with a new paradigm (IL-35 producing Tregs and Bregs) that is beyond TGF-β and IL-10 producing Treg cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

A miRNA181a/NFAT5 axis links impaired T cell tolerance induction with autoimmune type 1 diabetes

PubMed Central

Serr, Isabelle; Scherm, Martin G.; Zahm, Adam M.; Schug, Jonathan; Flynn, Victoria K.; Hippich, Markus; Kälin, Stefanie; Becker, Maike; Achenbach, Peter; Nikolaev, Alexei; Gerlach, Katharina; Liebsch, Nicole; Loretz, Brigitta; Lehr, Claus-Michael; Kirchner, Benedikt; Spornraft, Melanie; Haase, Bettina; Segars, James; Küper, Christoph; Palmisano, Ralf; Waisman, Ari; Willis, Richard A.; Kim, Wan-Uk; Weigmann, Benno; Kaestner, Klaus H.; Ziegler, Anette-Gabriele; Daniel, Carolin

2018-01-01

Molecular checkpoints that trigger the onset of islet autoimmunity or progression to human type 1 diabetes (T1D) are incompletely understood. Using T cells from children at an early stage of islet autoimmunity without clinical T1D, we find that a microRNA181a (miRNA181a)–mediated increase in signal strength of stimulation and costimulation links nuclear factor of activated T cells 5 (NFAT5) with impaired tolerance induction and autoimmune activation. We show that enhancing miRNA181a activity increases NFAT5 expression while inhibiting FOXP3+ regulatory T cell (Treg) induction in vitro. Accordingly, Treg induction is improved using T cells from NFAT5 knockout (NFAT5ko) animals, whereas altering miRNA181a activity does not affect Treg induction in NFAT5ko T cells. Moreover, high costimulatory signals result in phosphoinositide 3-kinase (PI3K)–mediated NFAT5, which interferes with FoxP3+ Treg induction. Blocking miRNA181a or NFAT5 increases Treg induction in murine and humanized models and reduces murine islet autoimmunity in vivo. These findings suggest targeting miRNA181a and/or NFAT5 signaling for the development of innovative personalized medicines to limit islet autoimmunity. PMID:29298866

Foxp3+ Regulatory T Cells Delay Expulsion of Intestinal Nematodes by Suppression of IL-9-Driven Mast Cell Activation in BALB/c but Not in C57BL/6 Mice

PubMed Central

Brenz, Yannick; Eschbach, Marie-Luise; Hartmann, Wiebke; Haben, Irma; Sparwasser, Tim; Huehn, Jochen; Kühl, Anja; Feyerabend, Thorsten B.; Rodewald, Hans-Reimer; Breloer, Minka

2014-01-01

Accumulating evidence suggests that IL-9-mediated immunity plays a fundamental role in control of intestinal nematode infection. Here we report a different impact of Foxp3+ regulatory T cells (Treg) in nematode-induced evasion of IL-9-mediated immunity in BALB/c and C57BL/6 mice. Infection with Strongyloides ratti induced Treg expansion with similar kinetics and phenotype in both strains. Strikingly, Treg depletion reduced parasite burden selectively in BALB/c but not in C57BL/6 mice. Treg function was apparent in both strains as Treg depletion increased nematode-specific humoral and cellular Th2 response in BALB/c and C57BL/6 mice to the same extent. Improved resistance in Treg-depleted BALB/c mice was accompanied by increased production of IL-9 and accelerated degranulation of mast cells. In contrast, IL-9 production was not significantly elevated and kinetics of mast cell degranulation were unaffected by Treg depletion in C57BL/6 mice. By in vivo neutralization, we demonstrate that increased IL-9 production during the first days of infection caused accelerated mast cell degranulation and rapid expulsion of S. ratti adults from the small intestine of Treg-depleted BALB/c mice. In genetically mast cell-deficient (Cpa3-Cre) BALB/c mice, Treg depletion still resulted in increased IL-9 production but resistance to S. ratti infection was lost, suggesting that IL-9-driven mast cell activation mediated accelerated expulsion of S. ratti in Treg-depleted BALB/c mice. This IL-9-driven mast cell degranulation is a central mechanism of S. ratti expulsion in both, BALB/c and C57BL/6 mice, because IL-9 injection reduced and IL-9 neutralization increased parasite burden in the presence of Treg in both strains. Therefore our results suggest that Foxp3+ Treg suppress sufficient IL-9 production for subsequent mast cell degranulation during S. ratti infection in a non-redundant manner in BALB/c mice, whereas additional regulatory pathways are functional in Treg-depleted C57BL/6 mice. PMID:24516385

Foxp3⁺ regulatory T cells delay expulsion of intestinal nematodes by suppression of IL-9-driven mast cell activation in BALB/c but not in C57BL/6 mice.

PubMed

Blankenhaus, Birte; Reitz, Martina; Brenz, Yannick; Eschbach, Marie-Luise; Hartmann, Wiebke; Haben, Irma; Sparwasser, Tim; Huehn, Jochen; Kühl, Anja; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Breloer, Minka

2014-02-01

Accumulating evidence suggests that IL-9-mediated immunity plays a fundamental role in control of intestinal nematode infection. Here we report a different impact of Foxp3⁺ regulatory T cells (Treg) in nematode-induced evasion of IL-9-mediated immunity in BALB/c and C57BL/6 mice. Infection with Strongyloides ratti induced Treg expansion with similar kinetics and phenotype in both strains. Strikingly, Treg depletion reduced parasite burden selectively in BALB/c but not in C57BL/6 mice. Treg function was apparent in both strains as Treg depletion increased nematode-specific humoral and cellular Th2 response in BALB/c and C57BL/6 mice to the same extent. Improved resistance in Treg-depleted BALB/c mice was accompanied by increased production of IL-9 and accelerated degranulation of mast cells. In contrast, IL-9 production was not significantly elevated and kinetics of mast cell degranulation were unaffected by Treg depletion in C57BL/6 mice. By in vivo neutralization, we demonstrate that increased IL-9 production during the first days of infection caused accelerated mast cell degranulation and rapid expulsion of S. ratti adults from the small intestine of Treg-depleted BALB/c mice. In genetically mast cell-deficient (Cpa3-Cre) BALB/c mice, Treg depletion still resulted in increased IL-9 production but resistance to S. ratti infection was lost, suggesting that IL-9-driven mast cell activation mediated accelerated expulsion of S. ratti in Treg-depleted BALB/c mice. This IL-9-driven mast cell degranulation is a central mechanism of S. ratti expulsion in both, BALB/c and C57BL/6 mice, because IL-9 injection reduced and IL-9 neutralization increased parasite burden in the presence of Treg in both strains. Therefore our results suggest that Foxp3⁺ Treg suppress sufficient IL-9 production for subsequent mast cell degranulation during S. ratti infection in a non-redundant manner in BALB/c mice, whereas additional regulatory pathways are functional in Treg-depleted C57BL/6 mice.

Exploring the induction of preproinsulin-specific Foxp3+ CD4+ Treg cells that inhibit CD8+ T cell-mediated autoimmune diabetes by DNA vaccination

PubMed Central

Stifter, Katja; Schuster, Cornelia; Schlosser, Michael; Boehm, Bernhard Otto; Schirmbeck, Reinhold

2016-01-01

DNA vaccination is a promising strategy to induce effector T cells but also regulatory Foxp3+ CD25+ CD4+ Treg cells and inhibit autoimmune disorders such as type 1 diabetes. Little is known about the antigen requirements that facilitate priming of Treg cells but not autoreactive effector CD8+ T cells. We have shown that the injection of preproinsulin (ppins)-expressing pCI/ppins vector into PD-1- or PD-L1-deficient mice induced Kb/A12-21-monospecific CD8+ T cells and autoimmune diabetes. A pCI/ppinsΔA12-21 vector (lacking the critical Kb/A12-21 epitope) did not induce autoimmune diabetes but elicited a systemic Foxp3+ CD25+ Treg cell immunity that suppressed diabetes induction by a subsequent injection of the diabetogenic pCI/ppins. TGF-β expression was significantly enhanced in the Foxp3+ CD25+ Treg cell population of vaccinated/ppins-primed mice. Ablation of Treg cells in vaccinated/ppins-primed mice by anti-CD25 antibody treatment abolished the protective effect of the vaccine and enabled diabetes induction by pCI/ppins. Adoptive transfer of Treg cells from vaccinated/ppins-primed mice into PD-L1−/− hosts efficiently suppressed diabetes induction by pCI/ppins. We narrowed down the Treg-stimulating domain to a 15-residue ppins76–90 peptide. Vaccine-induced Treg cells thus play a crucial role in the control of de novo primed autoreactive effector CD8+ T cells in this diabetes model. PMID:27406624

Mutual antagonism of TGF-beta and Interleukin-2 in cell survival and lineage commitment of induced regulatory T cells

PubMed Central

Tischner, D; Wiegers, G J; Fiegl, H; Drach, M; Villunger, A

2012-01-01

Transforming growth factor beta (TGF-β)- and Interleukin-2 (IL-2)-mediated signaling enables the generation and expansion of induced regulatory T (iTreg) cells that carry high hopes for the treatment of chronic inflammatory and autoimmune diseases. Knowledge about factors stabilizing their lineage commitment and lifespan, however, is limited. Here, we investigated the behavior of iTreg cells, derived from apoptosis-defective mouse mutants, during activated cell autonomous cell death, triggered by cytokine-deprivation, or activation-induced cell death (AICD) after restimulation of the T-cell receptor, and compared these responses with those of effector T cells. We observed that iTreg cells were much more sensitive to IL-2-deprivation but poorly susceptible to AICD. In fact, when apoptosis was compromised, T-cell receptor (TCR)-religation resulted in methylation-independent, ERK- and PI3K/mTOR-mediated loss of Foxp3 expression, impaired suppressive capacity and effector cytokine production. Although iTreg cells prevented colitis induction they rapidly lost Foxp3-GFP expression and gained ability to produce effector cytokines thereby imposing Th1 cell fate on resident effector cells. Surprisingly, iTreg cell conversion itself was limited by TGF-β-mediated Bim/Bcl2L11-dependent apoptosis. Hence, the very same cytokine that drives the generation of iTreg cells can trigger their demise. Our results provide novel insights in iTreg cell biology that will assist optimization of iTreg-based therapy. PMID:22322859

Regulatory CD4 T cells inhibit HIV-1 expression of other CD4 T cell subsets via interactions with cell surface regulatory proteins.

PubMed

Zhang, Mingce; Robinson, Tanya O; Duverger, Alexandra; Kutsch, Olaf; Heath, Sonya L; Cron, Randy Q

2018-03-01

During chronic HIV-1 infection, regulatory CD4 T cells (Tregs) frequently represent the largest subpopulation of CD4 T cell subsets, implying relative resistant to HIV-1. When HIV-1 infection of CD4 T cells was explored in vitro and ex vivo from patient samples, Tregs possessed lower levels of HIV-1 DNA and RNA in comparison with conventional effector and memory CD4 T cells. Moreover, Tregs suppressed HIV-1 expression in other CD4 T cells in an in vitro co-culture system. This suppression was mediated in part via multiple inhibitory surface proteins expressed on Tregs. Antibody blockade of CTLA-4, PD-1, and GARP on Tregs resulted in increased HIV-1 DNA integration and mRNA expression in neighboring CD4 T cells. Moreover, antibody blockade of Tregs inhibitory proteins resulted in increased HIV-1 LTR transcription in co-cultured CD4 T cells. Thus, Tregs inhibit HIV-1 infection of other CD4 T cell subsets via interactions with inhibitory cell surface proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

The role of regulatory T cells in the control of natural killer cells: relevance during tumor progression.

PubMed

Ghiringhelli, Francois; Ménard, Cédric; Martin, Francois; Zitvogel, Laurence

2006-12-01

Tumor immunosurveillance relies on cognate immune effectors [lymphocytes and interferon-gamma (IFN-gamma)] and innate immunity [natural killer (NK) cells, natural killer group 2, member D (NKG2D) ligands, perforin/granzyme, and tumor necrosis factor-related apoptosis-inducing ligand]. In parallel, tumor cells promote the expansion of CD4(+)CD25(+) regulatory T cells (Tregs) that counteract T-cell-based anti-tumor immunity. Moreover, accumulating evidence points to a critical role for Tregs in dampening NK cell immune responses. This review summarizes the findings showing that Tregs suppress NK cell effector functions in vitro and in vivo, i.e. homeostatic proliferation, cytotoxicity, and interleukin-12-mediated IFN-gamma production. The molecular mechanism involve selective expression of membrane-bound transforming growth factor-beta on Tregs, which downregulate NKG2D expression on NK cells in vitro and in vivo. The regulatory events dictating NK cell suppression by Tregs have been studied and are discussed. The pathological relevance of the Treg-NK cell interaction has been brought up in tumor models and in patients with cancer. Consequently, inhibition of Tregs through pharmacological interventions should be considered during NK-cell-based immunotherapy of cancer.

Self-Recognition Sensitizes Mouse and Human Regulatory T Cells to Low-Dose CD28 Superagonist Stimulation.

PubMed

Langenhorst, Daniela; Tabares, Paula; Gulde, Tobias; Becklund, Bryan R; Berr, Susanne; Surh, Charles D; Beyersdorf, Niklas; Hünig, Thomas

2017-01-01

In rodents, low doses of CD28-specific superagonistic monoclonal antibodies (CD28 superagonists, CD28SA) selectively activate regulatory T cells (Treg). This observation has recently been extended to humans, suggesting an option for the treatment of autoimmune and inflammatory diseases. However, a mechanistic explanation for this phenomenon is still lacking. Given that CD28SA amplify T cell receptor (TCR) signals, we tested the hypothesis that the weak tonic TCR signals received by conventional CD4 + T cells (Tconv) in the absence of cognate antigen require more CD28 signaling input for full activation than the stronger TCR signals received by self-reactive Treg. We report that in vitro , the response of mouse Treg and Tconv to CD28SA strongly depends on MHC class II expression by antigen-presenting cells. To separate the effect of tonic TCR signals from self-peptide recognition, we compared the response of wild-type Treg and Tconv to low and high CD28SA doses upon transfer into wild-type or H-2M knockout mice, which lack a self-peptide repertoire. We found that the superior response of Treg to low CD28SA doses was lost in the absence of self-peptide presentation. We also tested if potentially pathogenic autoreactive Tconv would benefit from self-recognition-induced sensitivity to CD28SA stimulation by transferring TCR transgenic OVA-specific Tconv into OVA-expressing mice and found that low-dose CD28SA application inhibited, rather than supported, their expansion, presumably due to the massive concomitant activation of Treg. Finally, we report that also in the in vitro response of human peripheral blood mononuclear cells to CD28SA, HLA II blockade interferes with the expansion of Treg by low-dose CD28SA stimulation. These results provide a rational basis for the further development of low-dose CD28SA therapy for the improvement of Treg activity.

Enhanced renewal of regulatory T cells in relation to CD4(+) conventional T lymphocytes in the peripheral compartment.

PubMed

Nogueira, Jeane de Souza; Canto, Fábio Barrozo do; Nunes, Caroline Fraga Cabral Gomes; Vianna, Pedro Henrique Oliveira; Paiva, Luciana de Souza; Nóbrega, Alberto; Bellio, Maria; Fucs, Rita

2016-02-01

CD4(+) Foxp3(+) regulatory T (Treg) cells are necessary for the maintenance of self-tolerance and T-cell homeostasis. This population is kept at stable frequencies in secondary lymphoid organs for the majority of the lifetime, despite permanent thymic emigration or in the face of thymic involution. Continuous competition is expected to occur between recently thymus-emigrated and resident Treg cells (either natural or post-thymically induced). In the present work, we analysed the renewal dynamics of Treg cells compared with CD4(+) Foxp3- conventional T cells (Tconv), using protocols of single or successive T-cell transfers into syngeneic euthymic or lymphopenic (nu/nu or RAG2(-/-)) mice, respectively. Our results show a higher turnover for Treg cells in the peripheral compartment, compared with Tconv cells, when B cell-sufficient euthymic or nude hosts are studied. This increased renewal within the Treg pool, shown by the greater replacement of resident Treg cells by donor counterparts, correlates with augmented rates of proliferation and is not modified following temporary environmental perturbations induced by inflammatory state or microbiota alterations. Notably, the preferential substitution of Treg lymphocytes was not observed in RAG2(-/-) hosts. We showed that limited B-cell replenishment in the RAG2(-/-) hosts decisively contributed to the altered peripheral T-cell homeostasis. Accordingly, weekly transfers of B cells to RAG2(-/-) hosts rescued the preferential substitution of Treg lymphocytes. Our study discloses a new aspect of T-cell homeostasis that depends on the presence of B lymphocytes to regulate the relative incorporation of recently arrived Treg and Tconv cells in the peripheral compartment. © 2015 John Wiley & Sons Ltd.

Most Do, but Some Do Not: CD4+CD25− T Cells, but Not CD4+CD25+ Treg Cells, Are Cytolytic When Redirected by a Chimeric Antigen Receptor (CAR)

PubMed Central

Hombach, Andreas A.; Abken, Hinrich

2017-01-01

Evidences are accumulating that CD4+ T cells can physiologically mediate antigen specific target cell lysis. By circumventing major histocompatibility complex (MHC)-restrictions through an engineered chimeric antigen receptor (CAR), CD4+ T cells lyse defined target cells as efficiently as do CD8+ T cells. However, the cytolytic capacity of redirected CD4+CD25− T cells, in comparison with CD4+CD25+ regulatory T (Treg) cells was so far not thoroughly defined. Treg cells require a strong CD28 signal together with CD3ζ for activation. We consequently used a CAR with combined CD28­CD3ζ signalling for redirecting CD4+CD25− T cells and CD4+CD25+ Treg cells from the same donor. CAR redirected activation of these T cell subsets and induced a distinct cytokine pattern with high IL-10 and a lack of IL-2 release by Treg cells. Despite strong antigen-specific activation, CAR Treg cells produced only weak target cell lysis, whereas CD4+CD25− CAR T cells were potent killers. Cytolysis did not correlate with the target cell sensitivity to Fas/FasL mediated killing; CD4+CD25− T cells upregulated perforin and granzyme B upon CAR activation, whereas Treg cells did less. The different cytolytic capacities of CAR redirected conventional CD4+ cells and Treg cells imply their use for different purposes in cell therapy. PMID:28850063

CD4+CD25+ Treg derived from hepatocellular carcinoma mice inhibits tumor immunity.

PubMed

Chen, Xin; Du, Yong; Huang, Zhiming

2012-01-01

CD4+CD25+ regulatory T cells (Tregs) play an essential role in the establishment and persistence of tumor immune suppression. Tregs can prevent anti-tumor-specific T cells from clearing the tumor, making Tregs a significant barrier for effective immunotherapy. An increase in the number of Tregs has been detected in the peripheral blood and tumor infiltrating lymphocytes of patients with hepatocellular carcinoma. Dendritic cells (DCs) are antigen-presenting cells that play a pivotal role in the initiation of immune responses. The evidence for their ability to act as natural adjuvant in the stimulation of specific anti-tumor cytotoxic T lymphocytes and in the induction of protective and therapeutic anti-tumor immunity is now overwhelming. The aim of our study was to investigate the variation of Tregs in hepatocellular carcinoma mice and how Tregs derived from the tumor mice affect DCs' function. We found that Tregs derived from the tumor mice down-regulated the expression of costimulatory molecules CD80/CD86 on DCs and inhibited the production of TNF-α and IL-12 from DCs. The suppressive function of Tregs was mediated by cell-to-cell contact, CTLA-4 expression and IL-10 secretion. In conclusion, these mechanisms acting in hepatocellular carcinoma may be necessary to better understand the immunosuppression of Tregs and helpful to the tumor immunotherapy. Copyright © 2012 Elsevier B.V. All rights reserved.

How regulatory T cells work

PubMed Central

Vignali, Dario A. A.; Collison, Lauren W.; Workman, Creg J.

2009-01-01

Regulatory T (Treg) cells are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases. However, they also limit beneficial responses by suppressing sterilizing immunity and limiting anti-tumour immunity. Given that Treg cells can have both beneficial and deleterious effects, there is considerable interest in determining their mechanisms of action. In this Review, we discuss the basic mechanisms used by Treg cells to mediate suppression, and discuss whether one or many of these mechanisms are likely to be crucial for Treg-cell function. In addition, we present the hypothesis that effector T cells may not be ‘innocent’ parties in this suppressive process and might in fact potentiate Treg-cell function. PMID:18566595

Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

PubMed

Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

2017-10-01

Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

Blocking immunosuppression by human Tregs in vivo with antibodies targeting integrin αVβ8.

PubMed

Stockis, Julie; Liénart, Stéphanie; Colau, Didier; Collignon, Amandine; Nishimura, Stephen L; Sheppard, Dean; Coulie, Pierre G; Lucas, Sophie

2017-11-21

Human regulatory T cells (Tregs) suppress other T cells by converting the latent, inactive form of TGF-β1 into active TGF-β1. In Tregs, TGF-β1 activation requires GARP, a transmembrane protein that binds and presents latent TGF-β1 on the surface of Tregs stimulated through their T cell receptor. However, GARP is not sufficient because transduction of GARP in non-Treg T cells does not induce active TGF-β1 production. RGD-binding integrins were shown to activate TGF-β1 in several non-T cell types. Here we show that αVβ8 dimers are present on stimulated human Tregs but not in other T cells, and that antibodies against αV or β8 subunits block TGF-β1 activation in vitro. We also show that αV and β8 interact with GARP/latent TGF-β1 complexes in human Tregs. Finally, a blocking antibody against β8 inhibited immunosuppression by human Tregs in a model of xenogeneic graft-vs.-host disease induced by the transfer of human T cells in immunodeficient mice. These results show that TGF-β1 activation on the surface of human Tregs implies an interaction between the integrin αVβ8 and GARP/latent TGF-β1 complexes. Immunosuppression by human Tregs can be inhibited by antibodies against GARP or against the integrin β8 subunit. Such antibodies may prove beneficial against cancer or chronic infections.

Two SHIPs passing in the middle of the immune system.

PubMed

Corey, Seth J; Mehta, Hrishikesh M; Stein, Paul L

2012-07-01

Immunity requires a complex, multiscale system of molecules, cells, and cytokines. In this issue of the European Journal of Immunology, Collazo et al. [Eur. J. Immunol. 2012. 42: 1785-1796] provide evidence that links the lipid phosphatase SHIP1 with the coordination of interactions between regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSCs). Using conditional knockouts of SHIP1 in either the myeloid or T-cell-lineage of mice, the authors show that the regulated development of Treg cells is controlled directly by cell-intrinsic SHIP1, and indirectly by extrinsic SHIP1 control of an unknown myeloid cell. Regulation of MDSCs is also determined by SHIP1 in an extrinsic manner, again via an as-yet-unknown myeloid cell. Furthermore, this extrinsic control of Treg cells and MDSCs is mediated in part by increased production of G-CSF, a growth factor critical for the production of neutrophils, in SHIP1-deficient mice. Thus, a physiologically important implication of this report is the collaboration between the innate and adaptive immune systems in fine tuning of Treg cells as discussed in this commentary. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Maternal Filarial Infection Influences the Development of Regulatory T Cells in Children from Infancy to Early Childhood.

PubMed

Bal, Madhusmita; Ranjit, Manoranjan; Achary, K Gopinath; Satapathy, Ashok K

2016-11-01

Children born from filarial infected mothers are comparatively more susceptible to filarial infection than the children born to uninfected mothers. But the mechanism of such increased susceptibility to infection in early childhood is not exactly known. Several studies have shown the association of active filarial infection with T cell hypo-responsiveness which is mediated by regulatory T cells (Tregs). Since the Tregs develop in the thymus from CD4+ CD25hi thymocytes at an early stage of the human fetus, it can be hypothesized that the maternal infection during pregnancy affects the development of Tregs in children at birth as well as early childhood. Hence the present study was designed to test the hypothesis by selecting a cohort of pregnant mothers and children born to them subsequently in a filarial endemic area of Odisha, India. A total number of 49 pregnant mothers and children born to them subsequently have been followed up (mean duration 4.4 years) in an area where the microfilariae (Mf) rate has come down to <1% after institution of 10 rounds of annual mass drug administration (MDA). The infection status of mother, cord and children were assessed through detection of microfilariae (Mf) and circulating filarial antigen (CFA). Expression of Tregs cells were measured by flow cytometry. The levels of IL-10 were evaluated by using commercially available ELISA kit. A significantly high level of IL-10 and Tregs have been observed in children born to infected mother compared to children of uninfected mother at the time of birth as well as during early childhood. Moreover a positive correlation between Tregs and IL-10 has been observed among the children born to infected mother. From these observations we predict that early priming of the fetal immune system by filarial antigens modulate the development of Tregs, which ultimately scale up the production of IL-10 in neonates and creates a milieu for high rate of acquisition of infection in children born to infected mothers. The mechanism of susceptibility and implication of the results in global elimination programme of filariasis has been discussed.

Maternal Filarial Infection Influences the Development of Regulatory T Cells in Children from Infancy to Early Childhood

PubMed Central

Bal, Madhusmita; Ranjit, Manoranjan; Achary, K. Gopinath; Satapathy, Ashok K.

2016-01-01

Background Children born from filarial infected mothers are comparatively more susceptible to filarial infection than the children born to uninfected mothers. But the mechanism of such increased susceptibility to infection in early childhood is not exactly known. Several studies have shown the association of active filarial infection with T cell hypo-responsiveness which is mediated by regulatory T cells (Tregs). Since the Tregs develop in the thymus from CD4+ CD25hi thymocytes at an early stage of the human fetus, it can be hypothesized that the maternal infection during pregnancy affects the development of Tregs in children at birth as well as early childhood. Hence the present study was designed to test the hypothesis by selecting a cohort of pregnant mothers and children born to them subsequently in a filarial endemic area of Odisha, India. Methodology and Principal finding A total number of 49 pregnant mothers and children born to them subsequently have been followed up (mean duration 4.4 years) in an area where the microfilariae (Mf) rate has come down to <1% after institution of 10 rounds of annual mass drug administration (MDA). The infection status of mother, cord and children were assessed through detection of microfilariae (Mf) and circulating filarial antigen (CFA). Expression of Tregs cells were measured by flow cytometry. The levels of IL-10 were evaluated by using commercially available ELISA kit. A significantly high level of IL-10 and Tregs have been observed in children born to infected mother compared to children of uninfected mother at the time of birth as well as during early childhood. Moreover a positive correlation between Tregs and IL-10 has been observed among the children born to infected mother. Significance From these observations we predict that early priming of the fetal immune system by filarial antigens modulate the development of Tregs, which ultimately scale up the production of IL-10 in neonates and creates a milieu for high rate of acquisition of infection in children born to infected mothers. The mechanism of susceptibility and implication of the results in global elimination programme of filariasis has been discussed. PMID:27861499

Reduced immunomodulation potential of bone marrow-derived mesenchymal stem cells induced CCR4+CCR6+ Th/Treg cell subset imbalance in ankylosing spondylitis

PubMed Central

2011-01-01

Introduction Ankylosing spondylitis (AS) is a chronic autoimmune disease, and the precise pathogenesis is largely unknown at present. Bone marrow-derived mesenchymal stem cells (BMSCs) with immunosuppressive and anti-inflammatory potential and Th17/Treg cells with a reciprocal relationship regulated by BMSCs have been reported to be involved in some autoimmune disorders. Here we studied the biological and immunological characteristics of BMSCs, the frequency and phenotype of CCR4+CCR6+ Th/Treg cells and their interaction in vitro in AS. Methods The biological and immunomodulation characteristics of BMSCs were examined by induced multiple-differentiation and two-way mixed peripheral blood mononuclear cell (PBMC) reactions or after stimulation with phytohemagglutinin, respectively. The interactions of BMSCs and PBMCs were detected with a direct-contact co-culturing system. CCR4+CCR6+ Th/Treg cells and surface markers of BMSCs were assayed using flow cytometry. Results The AS-BMSCs at active stage showed normal proliferation, cell viability, surface markers and multiple differentiation characteristics, but significantly reduced immunomodulation potential (decreased 68 ± 14%); the frequencies of Treg and Fox-P3+ cells in AS-PBMCs decreased, while CCR4+CCR6+ Th cells increased, compared with healthy donors. Moreover, the AS-BMSCs induced imbalance in the ratio of CCR4+CCR6+ Th/Treg cells by reducing Treg/PBMCs and increasing CCR4+CCR6+ Th/PBMCs, and also reduced Fox-P3+ cells when co-cultured with PBMCs. Correlation analysis showed that the immunomodulation potential of BMSCs has significant negative correlations with the ratio of CCR4+CCR6+ Th to Treg cells in peripheral blood. Conclusions The immunomodulation potential of BMSCs is reduced and the ratio of CCR4+CCR6+ Th/Treg cells is imbalanced in AS. The BMSCs with reduced immunomodulation potential may play a novel role in AS pathogenesis by inducing CCR4+CCR6+ Th/Treg cell imbalance. PMID:21338515

Food-allergic infants have impaired regulatory T-cell responses following in vivo allergen exposure.

PubMed

Dang, Thanh D; Allen, Katrina J; J Martino, David; Koplin, Jennifer J; Licciardi, Paul V; Tang, Mimi L K

2016-02-01

Regulatory T cells (Tregs) are critical for development of oral tolerance, and studies suggest that dysfunction of Tregs may lead to food allergy. However, to date, no study has investigated Treg responses following in vivo exposure to peanut or egg allergens in humans. To examine changes in peripheral blood CD4(+) CD25(+) Foxp3(+) Treg populations (total, activated and naive) in food-allergic, food-sensitized but tolerant, and healthy (non-sensitized non-allergic) patients over time following in vivo allergen exposure. A subset of infants from the HealthNuts study with egg or peanut allergy (n = 37), egg or peanut sensitization (n = 35), or who were non-sensitized non-allergic (n = 15) were studied. All subjects underwent oral food challenge (OFC) to egg or peanut. PBMCs were obtained within 1 h of OFC (in vivo allergen exposure), and Treg populations enumerated ex vivo on day 0, and after 2 and 6 days rest in vitro. Non-allergic infants showed stable total Treg frequencies over time; food-sensitized infants had a transient fall in Treg percentage with recovery to baseline by day 6 (6.87% day 0, 5.27% day 2, 6.5% day 6); and food-allergic infants showed persistent reduction in Treg (6.85% day 0, 5.4% day 2, 6.2% day 6) following in vivo allergen exposure. Furthermore, food-allergic infants had a significantly lower ratio of activated Treg:activated T cells (10.5 ± 0.77) at day 0 compared to food-sensitized (14.6 ± 1.24) and non-allergic subjects (16.2 ± 1.23). Our data suggest that the state of allergen sensitization is associated with depletion of Treg following allergen exposure. Impaired capacity to regenerate the Treg pool following allergen exposure may be an important factor that determines clinical allergy vs. sensitization without allergic reaction. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Reciprocal relationship of T regulatory cells and monocytic myeloid-derived suppressor cells in LP-BM5 murine retrovirus-induced immunodeficiency.

PubMed

O'Connor, Megan A; Vella, Jennifer L; Green, William R

2016-02-01

Immunomodulatory cellular subsets, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (Tregs), contribute to the immunosuppressive tumour microenvironment and are targets of immunotherapy, but their role in retroviral-associated immunosuppression is less well understood. Due to known crosstalk between Tregs and MDSCs in the tumour microenvironment, and also their hypothesized involvement during human immunodeficiency virus/simian immunodeficiency virus infection, studying the interplay between these immune cells during LP-BM5 retrovirus-induced murine AIDS is of interest. IL-10-producing FoxP3+ Tregs expanded after LP-BM5 infection. Following in vivo adoptive transfer of natural Treg (nTreg)-depleted CD4+T-cells, and subsequent LP-BM5 retroviral infection, enriched monocytic MDSCs (M-MDSCs) from these nTreg-depleted mice displayed altered phenotypic subsets. In addition, M-MDSCs from LP-BM5-infected nTreg-depleted mice exhibited increased suppression of T-cell, but not B-cell, responses, compared with M-MDSCs derived from non-depleted LP-BM5-infected controls. Additionally, LP-BM5-induced M-MDSCs modulated the production of IL-10 by FoxP3+ Tregs in vitro. These collective data highlight in vitro and for the first time, to the best of our knowledge, in vivo reciprocal modulation between retroviral-induced M-MDSCs and Tregs, and may provide insight into the immunotherapeutic targeting of such regulatory cells during retroviral infection.

Tumor inhibitory T cell immunity may be largely a transplantation artifact not necessarily dependent upon a lack of Tregs.

PubMed

Prehn, Richmond T; Prehn, Liisa M

2013-06-25

There exists a very large literature suggesting that T cells come in a variety of species and that without the action of Tregs tumors would seldom survive inhibition by T cell effectors. We believe that much of the evidence supporting the role of Tregs in cancer is compatible with a perhaps simpler hypothesis based upon the demonstration that that small quantities of effector T cells tend to stimulate tumors while larger quantities of seemingly the same cells are inhibitory (an hormesis-like effect). This possibility seems to destroy much of the need to postulate a role for T cell suppressors (Tregs) in cancer, but the exposure of effector T cells to antigen may convert them into Tregs (Tregs do exist). Furthermore, many other data suggest the possibility that immune inhibition of cancer could be a laboratory artifact seldom if ever seen in unmodified nature.

Tumor inhibitory T cell immunity may be largely a transplantation artifact not necessarily dependent upon a lack of Tregs

PubMed Central

2013-01-01

There exists a very large literature suggesting that T cells come in a variety of species and that without the action of Tregs tumors would seldom survive inhibition by T cell effectors. We believe that much of the evidence supporting the role of Tregs in cancer is compatible with a perhaps simpler hypothesis based upon the demonstration that that small quantities of effector T cells tend to stimulate tumors while larger quantities of seemingly the same cells are inhibitory (an hormesis-like effect). This possibility seems to destroy much of the need to postulate a role for T cell suppressors (Tregs) in cancer, but the exposure of effector T cells to antigen may convert them into Tregs (Tregs do exist). Furthermore, many other data suggest the possibility that immune inhibition of cancer could be a laboratory artifact seldom if ever seen in unmodified nature. PMID:23800315

Regulatory T cells in skin.

PubMed

Ali, Niwa; Rosenblum, Michael D

2017-11-01

Foxp3 + CD4 + regulatory T (Treg) cells are a subset of immune cells that function to regulate tissue inflammation. Skin is one of the largest organs and is home to a large proportion of the body's Treg cells. However, relative to other tissues (such as the spleen and gastrointestinal tract) the function of Treg cells in skin is less well defined. Here, we review our understanding of how Treg cells migrate to skin and the cellular and molecular pathways required for their maintenance in this tissue. In addition, we outline what is known about the specialized functions of Treg cells in skin. Namely, the orchestration of stem cell-mediated hair follicle regeneration, augmentation of wound healing, and promoting adaptive immune tolerance to skin commensal microbes. A comprehensive understanding of the biology of skin Treg cells may lead to novel therapeutic approaches that preferentially target these cells to treat cutaneous autoimmunity, skin cancers and disorders of skin regeneration. © 2017 John Wiley & Sons Ltd.

All-trans retinoic acid and rapamycin synergize with transforming growth factor-β1 to induce regulatory T cells but confer different migratory capacities.

PubMed

Jhunjhunwala, Siddharth; Chen, Leo C; Nichols, Erin E; Thomson, Angus W; Raimondi, Giorgio; Little, Steven R

2013-11-01

Tregs play important roles in maintaining immune homeostasis, and thus, therapies based on Treg are promising candidates for the treatment for a variety of immune-mediated disorders. These therapies, however, face the significant challenge of obtaining adequate numbers of Tregs from peripheral blood that maintains suppressive function following extensive expansion. Inducing Tregs from non-Tregs offers a viable alternative. Different methods to induce Tregs have been proposed and involve mainly treating cells with TGF-β-iTreg. However, use of TGF-β alone is not sufficient to induce stable Tregs. ATRA or rapa has been shown to synergize with TGF-β to induce stable Tregs. Whereas TGF-β plus RA-iTregs have been well-described in the literature, the phenotype, function, and migratory characteristics of TGF-β plus rapa-iTreg have yet to be elucidated. Herein, we describe the phenotype and function of mouse rapa-iTreg and reveal that these cells differ in their in vivo homing capacity when compared with mouse RA-iTreg and mouse TGF-β-iTreg. This difference in migratory activity significantly affects the therapeutic capacity of each subset in a mouse model of colitis. We also describe the characteristics of iTreg generated in the presence of TGF-β, RA, and rapa.

Dynamics and functions of CD4⁺CD25 (high) regulatory T lymphocytes in Chinese rhesus macaques during the early stage of infection with SIVmac239.

PubMed

Li, Shao-You; Xia, Hou-Jun; Dai, Zheng-Xi; Zhang, Gao-Hong; Fan, Bo; Li, Ming-Hua; Wang, Rui-Rui; Zheng, Yong-Tang

2012-05-01

CD4(+)CD25(high) regulatory T cells (Treg), which are a specialized subset of T cells, play an important role in the prevention of autoimmune diseases, maintenance of immune system homeostasis and tolerance to self-antigens. Chinese rhesus macaques (CRMs) are widely used in preclinical research on potential therapeutic drugs, vaccines and mechanisms of human diseases. However, the basic immunological characterization of Treg cells of CRMs has not been well established. To characterize Treg cells, peripheral blood of 43 adult CRMs was analyzed for CD4+ T lymphocytes by flow cytometry. It was found that Treg cells ranged from 1.52% to 11.1% of CD4+ T cells, and the average value was 5.7%. With our SIV-infected CRM model, through further studies, it was found that Treg cells in peripheral blood increased both in relative and absolute quantities. Moreover, Treg cells maintained their functions by suppressing Th1 cytokine secretion of their target cells. The results show that Treg cells might render cellular immunity against SIV viruses dysfunctional during the early stage after infection.

Pretransplant Recipient Circulating CD4+CD127lo/- Tumor Necrosis Factor Receptor 2+ Regulatory T Cells: A Surrogate of Regulatory T Cell-Suppressive Function and Predictor of Delayed and Slow Graft Function After Kidney Transplantation.

PubMed

Nguyen, Minh-Tri J P; Fryml, Elise; Sahakian, Sossy K; Liu, Shuqing; Cantarovich, Marcelo; Lipman, Mark; Tchervenkov, Jean I; Paraskevas, Steven

2016-02-01

Delayed graft function (DGF) and slow graft function (SGF) are ischemia-reperfusion-associated acute kidney injuries (AKI) that decrease long-term graft survival after kidney transplantation. Regulatory T (Treg) cells are protective in murine AKI, and their suppressive function predictive of AKI in kidney transplantation. The conventional Treg cell function coculture assay is however time-consuming and labor intensive. We sought a simpler alternative to measure Treg cell function and predict AKI. In this prospective observational cohort study, pretransplant recipient circulating CD4+CD25+CD127lo/- and CD4+CD127lo/- tumor necrosis factor receptor 2 (TNFR2)+ Treg cells were measured by flow cytometry in 76 deceased donor kidney transplant recipients (DGF, n = 18; SGF, n = 34; immediate graft function [IGF], n = 24). In a subset of 37 recipients, pretransplant circulating Treg cell-suppressive function was also quantified by measuring the suppression of autologous effector T-cell proliferation by Treg cell in coculture. The TNFR2+ expression on CD4+CD127lo/- T cells correlated with Treg cell-suppressive function (r = 0.63, P < 0.01). In receiver operating characteristic curves, percentage and absolute number of CD4+CD127lo/-TNFR2+ Treg cell predicted DGF from non-DGF (IGF + SGF) with area under the curves of 0.75 and 0.77, respectively, and also AKI (DGF + SGF) from IGF with area under the curves of 0.76 and 0.72, respectively (P < 0.01). Prediction of AKI (DGF + SGF) from IGF remained significant in multivariate logistic regression accounting for cold ischemic time, donor age, previous transplant, and pretransplant dialysis modality. Pretransplant recipient circulating CD4+CD127lo/-TNFR2+ Treg cell is potentially a simpler alternative to Treg cell function as a pretransplant recipient immune marker for AKI (DGF + SGF), independent from donor and organ procurement characteristics.

Vagotomy Affects the Development of Oral Tolerance and Increases Susceptibility to Develop Colitis Independently of α-7 Nicotinic Receptor

PubMed Central

Di Giovangiulio, Martina; Bosmans, Goele; Meroni, Elisa; Stakenborg, Nathalie; Florens, Morgane; Farro, Giovanna; Gomez-Pinilla, Pedro J; Matteoli, Gianluca; Boeckxstaens, Guy E

2016-01-01

Vagotomy (VGX) increases the susceptibility to develop colitis suggesting a crucial role for the cholinergic anti-inflammatory pathway in the regulation of the immune responses. Since oral tolerance and the generation of regulatory T cells (Tregs) are crucial to preserve mucosal immune homeostasis, we studied the effect of vagotomy and the involvement of α7 nicotinic receptors (α7nAChR) at the steady state and during colitis. Therefore, the development of both oral tolerance and colitis (induced by dextran sulfate sodium (DSS) or via T cell transfer) was studied in vagotomized mice and in α7nAChR-/- mice. VGX, but not α7nAChR deficiency, prevented oral tolerance establishment. This effect was associated with reduced Treg conversion in the lamina propria and mesenteric lymphnodes. To the same extent, vagotomized mice, but not α7nAChR-/- mice, developed a more severe DSS colitis compared with control mice treated with DSS, associated with a decreased number of colonic Tregs. However, neither VGX nor absence of α7nAChR in recipient mice affected colitis development in the T cell transfer model. In line, deficiency of α7nAChR exclusively in T cells did not influence the development of colitis induced by T cell transfer. Our results indicate a key role for the vagal intestinal innervation in the development of oral tolerance and colitis, most likely by modulating induction of Tregs independently of α7nAChR. PMID:27341335

Identity and Diversity of Human Peripheral Th and T Regulatory Cells Defined by Single-Cell Mass Cytometry.

PubMed

Kunicki, Matthew A; Amaya Hernandez, Laura C; Davis, Kara L; Bacchetta, Rosa; Roncarolo, Maria-Grazia

2018-01-01

Human CD3 + CD4 + Th cells, FOXP3 + T regulatory (Treg) cells, and T regulatory type 1 (Tr1) cells are essential for ensuring peripheral immune response and tolerance, but the diversity of Th, Treg, and Tr1 cell subsets has not been fully characterized. Independent functional characterization of human Th1, Th2, Th17, T follicular helper (Tfh), Treg, and Tr1 cells has helped to define unique surface molecules, transcription factors, and signaling profiles for each subset. However, the adequacy of these markers to recapitulate the whole CD3 + CD4 + T cell compartment remains questionable. In this study, we examined CD3 + CD4 + T cell populations by single-cell mass cytometry. We characterize the CD3 + CD4 + Th, Treg, and Tr1 cell populations simultaneously across 23 memory T cell-associated surface and intracellular molecules. High-dimensional analysis identified several new subsets, in addition to the already defined CD3 + CD4 + Th, Treg, and Tr1 cell populations, for a total of 11 Th cell, 4 Treg, and 1 Tr1 cell subsets. Some of these subsets share markers previously thought to be selective for Treg, Th1, Th2, Th17, and Tfh cells, including CD194 (CCR4) + FOXP3 + Treg and CD183 (CXCR3) + T-bet + Th17 cell subsets. Unsupervised clustering displayed a phenotypic organization of CD3 + CD4 + T cells that confirmed their diversity but showed interrelation between the different subsets, including similarity between Th1-Th2-Tfh cell populations and Th17 cells, as well as similarity of Th2 cells with Treg cells. In conclusion, the use of single-cell mass cytometry provides a systems-level characterization of CD3 + CD4 + T cells in healthy human blood, which represents an important baseline reference to investigate abnormalities of different subsets in immune-mediated pathologies. Copyright © 2017 by The American Association of Immunologists, Inc.

Impaired Th1 immunity in ovarian cancer patients is mediated by TNFR2+ Tregs within the tumor microenvironment.

PubMed

Govindaraj, Chindu; Scalzo-Inguanti, Karen; Madondo, Mutsa; Hallo, Julene; Flanagan, Katie; Quinn, Michael; Plebanski, Magdalena

2013-10-01

Ovarian cancer is a prevalent gynecological malignancy with potent immune-suppression capabilities; regulatory T cells (Tregs) are significant contributors to this immune-suppression. As ovarian cancer patients present with high levels of TNF and Tregs expressing TNFR2 are associated with maximal suppressive capacity, we investigated TNFR2+ Tregs within these patients. Indeed, TNFR2+ Tregs from tumor-associated ascites were the most potent suppressor T cell fraction. They were abundantly present within the ascites and more suppressive than peripheral blood TNFR2+ Tregs in patients. The increased suppressive capacity can be explained by a distinct cell surface expression profile, which includes high levels of CD39, CD73, TGF-β and GARP. Additionally, CD73 expression level on TNFR2+ Tregs was inversely correlated with IFN-γ production by effector T cells. This Treg fraction can be selectively recruited into the ascites from the peripheral blood of patients. Targeting TNFR2+ Tregs may offer new approaches to enhance the poor survival rates of ovarian cancer. © 2013.

Release of active TGF-β1 from the latent TGF-β1/GARP complex on T regulatory cells is mediated by integrin β8.

PubMed

Edwards, Justin P; Thornton, Angela M; Shevach, Ethan M

2014-09-15

Activated T regulatory cells (Tregs) express latent TGF-β1 on their cell surface bound to GARP. Although integrins have been implicated in mediating the release of active TGF-β1 from the complex of latent TGF-β1 and latent TGF-β1 binding protein, their role in processing latent TGF-β1 from the latent TGF-β1/GARP complex is unclear. Mouse CD4(+)Foxp3(+) Treg, but not CD4(+)Foxp3(-) T cells, expressed integrin β8 (Itgb8) as detected by quantitative RT-PCR. Itgb8 expression was a marker of thymically derived (t)Treg, because it could not be detected on Foxp3(+)Helios(-) Tregs or on Foxp3(+) T cells induced in vitro. Tregs from Itgb8 conditional knockouts exhibited normal suppressor function in vitro and in vivo in a model of colitis but failed to provide TGF-β1 to drive Th17 or induced Treg differentiation in vitro. In addition, Itgb8 knockout Tregs expressed higher levels of latent TGF-β1 on their cell surface consistent with defective processing. Thus, integrin αvβ8 is a marker of tTregs and functions in a cell intrinsic manner in mediating the processing of latent TGF-β1 from the latent TGF-β1/GARP complex on the surface of tTregs.

Pivotal Advance: Heme oxygenase 1 expression by human CD4+ T cells is not sufficient for their development of immunoregulatory capacity.

PubMed

Biburger, Markus; Theiner, Gabi; Schädle, Mirjam; Schuler, Gerold; Tiegs, Gisa

2010-02-01

HO-1 is the only inducible one of three isoenzymes that catalyzes the oxidative degradation of heme. HO-1 is inducible by various cellular stress factors and exerts cytoprotective and immunomodulatory effects. Recent publications demonstrated that HO-1 is constitutively expressed by CD4(+)CD25(+) T(regs) and induced in CD4(+)CD25(-) T cells upon FoxP3 transfection. Here, we investigated whether HO-1 was essential and sufficient for human T(regs) to exert immunosuppression in vitro. PGJ(2) induced pronounced expression of HO-1 in CD4(+)CD25(-) T cells without accompanying FoxP3 induction. Treatment of CD4(+)CD25(-) T cells with PGJ(2) decreased their proliferation, whereas the HO-1 inhibitor SnPP enhanced the proliferation of HO-1-expressing T(regs), suggesting that HO-1 may modulate the proliferative capacity of T lymphocytes. HO-1 modulation by SnPP treatment of T(regs) or PGJ(2) treatment of CD4(+)CD25(-) T cells neither suppressed nor induced immune-modulatory function in these cells, respectively, as measured by responder-cell proliferation and/or IL-2 production. In summary, these data suggest that HO-1 expression by T(regs) might contribute to their typical reluctance to proliferate but does not account independently for their suppressive functions.

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

PubMed Central

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

A rare subset of skin-tropic regulatory T cells expressing Il10/Gzmb inhibits the cutaneous immune response.

PubMed

Ikebuchi, Ryoyo; Teraguchi, Shunsuke; Vandenbon, Alexis; Honda, Tetsuya; Shand, Francis H W; Nakanishi, Yasutaka; Watanabe, Takeshi; Tomura, Michio

2016-10-19

Foxp3 + regulatory T cells (Tregs) migrating from the skin to the draining lymph node (dLN) have a strong immunosuppressive effect on the cutaneous immune response. However, the subpopulations responsible for their inhibitory function remain unclear. We investigated single-cell gene expression heterogeneity in Tregs from the dLN of inflamed skin in a contact hypersensitivity model. The immunosuppressive genes Ctla4 and Tgfb1 were expressed in the majority of Tregs. Although Il10-expressing Tregs were rare, unexpectedly, the majority of Il10-expressing Tregs co-expressed Gzmb and displayed Th1-skewing. Single-cell profiling revealed that CD43 + CCR5 + Tregs represented the main subset within the Il10/Gzmb-expressing cell population in the dLN. Moreover, CD43 + CCR5 + CXCR3 - Tregs expressed skin-tropic chemokine receptors, were preferentially retained in inflamed skin and downregulated the cutaneous immune response. The identification of a rare Treg subset co-expressing multiple immunosuppressive molecules and having tissue-remaining capacity offers a novel strategy for the control of skin inflammatory responses.

Differential effects of α4β7 and GPR15 on homing of effector and regulatory T cells from patients with UC to the inflamed gut in vivo

PubMed Central

Fischer, Anika; Zundler, Sebastian; Atreya, Raja; Rath, Timo; Voskens, Caroline; Hirschmann, Simon; López-Posadas, Rocío; Watson, Alastair; Becker, Christoph; Schuler, Gerold; Neufert, Clemens; Atreya, Imke; Neurath, Markus F

2016-01-01

Objective Gut homing of lymphocytes via adhesion molecules has recently emerged as new target for therapy in IBDs. We aimed to analyse the in vivo homing of effector (Teff) and regulatory (Treg) T cells to the inflamed gut via α4β7 and G protein receptor GPR15. Design We assessed the expression of homing receptors on T cells in peripheral blood and inflamed mucosa. We studied the migration pattern and homing of Teff and Treg cells to the inflamed gut using intravital confocal microscopy and FACS in a humanised mouse model in dextran sodium sulfate-treated NSG (NOD.Cg-Prkdcscid-Il2rgtm1Wjl/SzJ) mice. Results Expression of GPR15 and α4β7 was significantly increased on Treg rather than Teff cells in peripheral blood of patients with UC as compared with Crohn’s disease and controls. In vivo analysis in a humanised mouse model showed augmented gut homing of UC Treg cells as compared with controls. Moreover, suppression of UC (but not control) Teff and Treg cell homing was noted upon treatment with the α4β7 antibody vedolizumab. In contrast, siRNA blockade of GPR15 had only effects on homing of Teff cells but did not affect Treg homing in UC. Clinical vedolizumab treatment was associated with marked expansion of UC Treg cells in peripheral blood. Conclusions α4β7 rather than GPR15 is crucial for increased colonic homing of UC Treg cells in vivo, while both receptors control UC Teff cell homing. Vedolizumab treatment impairs homing of UC Treg cells leading to their accumulation in peripheral blood with subsequent suppression of systemic Teff cell expansion. PMID:26209553

CD4+VEGFR1(HIGH) T cell as a novel Treg subset regulates inflammatory bowel disease in lymphopenic mice.

PubMed

Shin, Jin-Young; Yoon, Il-Hee; Lim, Jong-Hyung; Shin, Jun-Seop; Nam, Hye-Young; Kim, Yong-Hee; Cho, Hyoung-Soo; Hong, So-Hee; Kim, Jung-Sik; Lee, Won-Woo; Park, Chung-Gyu

2015-09-01

Regulatory T cells (Tregs) are a specialized subpopulation of T cells that control the immune response and thereby maintain immune system homeostasis and tolerance to self-antigens. Many subsets of CD4(+) Tregs have been identified, including Foxp3(+), Tr1, Th3, and Foxp3neg iT(R)35 cells. In this study, we identified a new subset of CD4(+)VEGFR1(high) Tregs that have immunosuppressive capacity. CD4(+)VEGFR1high T cells, which constitute approximately 1.0% of CD4(+) T cells, are hyporesponsive to T-cell antigen receptor stimulation. Surface marker and FoxP3 expression analysis revealed that CD4(+)VEGFR1(high) T cells are distinct from known Tregs. CD4(+)VEGFR1(high) T cells suppressed the proliferation of CD4(+)CD25(-) T cell as efficiently as CD4(+)CD25(high) natural Tregs in a contact-independent manner. Furthermore, adoptive transfer of CD4(+)VEGFR1(+) T cells from wild type to RAG-2-deficient C57BL/6 mice inhibited effector T-cell-mediated inflammatory bowel disease. Thus, we report CD4(+) VEGFR1(high) T cells as a novel subset of Tregs that regulate the inflammatory response in the intestinal tract.

IL-33-mediated protection against experimental cerebral malaria is linked to induction of type 2 innate lymphoid cells, M2 macrophages and regulatory T cells.

PubMed

Besnard, Anne-Gaelle; Guabiraba, Rodrigo; Niedbala, Wanda; Palomo, Jennifer; Reverchon, Flora; Shaw, Tovah N; Couper, Kevin N; Ryffel, Bernhard; Liew, Foo Y

2015-02-01

Cerebral malaria (CM) is a complex parasitic disease caused by Plasmodium sp. Failure to establish an appropriate balance between pro- and anti-inflammatory immune responses is believed to contribute to the development of cerebral pathology. Using the blood-stage PbA (Plasmodium berghei ANKA) model of infection, we show here that administration of the pro-Th2 cytokine, IL-33, prevents the development of experimental cerebral malaria (ECM) in C57BL/6 mice and reduces the production of inflammatory mediators IFN-γ, IL-12 and TNF-α. IL-33 drives the expansion of type-2 innate lymphoid cells (ILC2) that produce Type-2 cytokines (IL-4, IL-5 and IL-13), leading to the polarization of the anti-inflammatory M2 macrophages, which in turn expand Foxp3 regulatory T cells (Tregs). PbA-infected mice adoptively transferred with ILC2 have elevated frequency of M2 and Tregs and are protected from ECM. Importantly, IL-33-treated mice deleted of Tregs (DEREG mice) are no longer able to resist ECM. Our data therefore provide evidence that IL-33 can prevent the development of ECM by orchestrating a protective immune response via ILC2, M2 macrophages and Tregs.

IL-33-Mediated Protection against Experimental Cerebral Malaria Is Linked to Induction of Type 2 Innate Lymphoid Cells, M2 Macrophages and Regulatory T Cells

PubMed Central

Besnard, Anne-Gaelle; Guabiraba, Rodrigo; Niedbala, Wanda; Palomo, Jennifer; Reverchon, Flora; Shaw, Tovah N.; Couper, Kevin N.; Ryffel, Bernhard; Liew, Foo Y.

2015-01-01

Cerebral malaria (CM) is a complex parasitic disease caused by Plasmodium sp. Failure to establish an appropriate balance between pro- and anti-inflammatory immune responses is believed to contribute to the development of cerebral pathology. Using the blood-stage PbA (Plasmodium berghei ANKA) model of infection, we show here that administration of the pro-Th2 cytokine, IL-33, prevents the development of experimental cerebral malaria (ECM) in C57BL/6 mice and reduces the production of inflammatory mediators IFN-γ, IL-12 and TNF-α. IL-33 drives the expansion of type-2 innate lymphoid cells (ILC2) that produce Type-2 cytokines (IL-4, IL-5 and IL-13), leading to the polarization of the anti-inflammatory M2 macrophages, which in turn expand Foxp3 regulatory T cells (Tregs). PbA-infected mice adoptively transferred with ILC2 have elevated frequency of M2 and Tregs and are protected from ECM. Importantly, IL-33-treated mice deleted of Tregs (DEREG mice) are no longer able to resist ECM. Our data therefore provide evidence that IL-33 can prevent the development of ECM by orchestrating a protective immune response via ILC2, M2 macrophages and Tregs. PMID:25659095

Altered status of CD4(+)CD25(+) regulatory T cells in patients with acute coronary syndromes.

PubMed

Mor, Adi; Luboshits, Galia; Planer, David; Keren, Gad; George, Jacob

2006-11-01

Considerable evidence supports the role of innate and adaptive immunity in the progression and destabilization of the atheromatous plaque. Naturally occurring CD4(+)CD25(+) regulatory T cells (Tregs) are a subpopulation of lymphocytes that are capable of suppressing the progression of experimental autoimmune disorders. We have hypothesized that peripheral numbers and function of Tregs would be deranged in patients with acute coronary syndromes (ACS). Peripheral numbers of Tregs were evaluated by FACS employing labelled antibodies to CD4 and CD25. Functional suppressive properties of Tregs were assayed by establishing a triple-cell culture in which purified Tregs were incubated with irradiated antigen-presenting cells and anti-CD3-activated responder T cells. Proliferation in the presence or absence of oxidized LDL (oxLDL) was evaluated by thymidine incorporation. mRNA and protein content of foxp3, a master transcriptional regulator of Tregs, were determined for all subjects. Patients with ACS exhibited significantly reduced numbers of peripheral Tregs as compared with patients with stable angina and normal coronary artery subjects. Moreover, oxLDL induced a more profound reduction in Treg numbers in patients with ACS. Tregs in ACS patients were significantly compromised as their ability to suppress responder CD4(+)CD25(-) T-cell proliferation was attenuated. mRNA and protein content of foxp3 were significantly reduced in purified Tregs obtained from patients with ACS. In patients with ACS, naturally occurring CD4(+)CD25(+) Treg numbers are reduced and their functional properties compromised. These findings may aid in understanding the mechanisms leading to culprit plaque associated T-cell activation in patients with ACS.

Umbilical cord blood regulatory T-cell expansion and functional effects of tumor necrosis factor receptor family members OX40 and 4-1BB expressed on artificial antigen-presenting cells

PubMed Central

Harker-Murray, Paul; Porter, Stephen B.; Merkel, Sarah C.; Londer, Aryel; Taylor, Dawn K.; Bina, Megan; Panoskaltsis-Mortari, Angela; Rubinstein, Pablo; Van Rooijen, Nico; Golovina, Tatiana N.; Suhoski, Megan M.; Miller, Jeffrey S.; Wagner, John E.; June, Carl H.; Riley, James L.

2008-01-01

Previously, we showed that human umbilical cord blood (UCB) regulatory T cells (Tregs) could be expanded approximately 100-fold using anti-CD3/28 monoclonal antibody (mAb)–coated beads to provide T-cell receptor and costimulatory signals. Because Treg numbers from a single UCB unit are limited, we explored the use of cell-based artificial antigen-presenting cells (aAPCs) preloaded with anti-CD3/28 mAbs to achieve higher levels of Treg expansion. Compared with beads, aAPCs had similar expansion properties while significantly increasing transforming growth factor β (TGF-β) secretion and the potency of Treg suppressor function. aAPCs modified to coexpress OX40L or 4-1BBL expanded UCB Tregs to a significantly greater extent than bead- or nonmodified aAPC cultures, reaching mean expansion levels exceeding 1250-fold. Despite the high expansion and in contrast to studies using other Treg sources, neither OX40 nor 4-1BB signaling of UCB Tregs reduced in vitro suppression. UCB Tregs expanded with 4-1BBL expressing aAPCs had decreased levels of proapoptotic bim. UCB Tregs expanded with nonmodified or modified aAPCs versus beads resulted in higher survival associated with increased Treg persistence in a xeno-geneic graft-versus-host disease lethality model. These data offer a novel approach for UCB Treg expansion using aAPCs, including those coexpressing OX40L or 4-1BBL. PMID:18645038

CD137+CD154− Expression As a Regulatory T Cell (Treg)-Specific Activation Signature for Identification and Sorting of Stable Human Tregs from In Vitro Expansion Cultures

PubMed Central

Nowak, Anna; Lock, Dominik; Bacher, Petra; Hohnstein, Thordis; Vogt, Katrin; Gottfreund, Judith; Giehr, Pascal; Polansky, Julia K.; Sawitzki, Birgit; Kaiser, Andrew; Walter, Jörn; Scheffold, Alexander

2018-01-01

Regulatory T cells (Tregs) are an attractive therapeutic tool for several different immune pathologies. Therapeutic Treg application often requires prolonged in vitro culture to generate sufficient Treg numbers or to optimize their functionality, e.g., via genetic engineering of their antigen receptors. However, purity of clinical Treg expansion cultures is highly variable, and currently, it is impossible to identify and separate stable Tregs from contaminating effector T cells, either ex vivo or after prior expansion. This represents a major obstacle for quality assurance of expanded Tregs and raises significant safety concerns. Here, we describe a Treg activation signature that allows identification and sorting of epigenetically imprinted Tregs even after prolonged in vitro culture. We show that short-term reactivation resulted in expression of CD137 but not CD154 on stable FoxP3+ Tregs that displayed a demethylated Treg-specific demethylated region, high suppressive potential, and lack of inflammatory cytokine expression. We also applied this Treg activation signature for rapid testing of chimeric antigen receptor functionality in human Tregs and identified major differences in the signaling requirements regarding CD137 versus CD28 costimulation. Taken together, CD137+CD154− expression emerges as a universal Treg activation signature ex vivo and upon in vitro expansion allowing the identification and isolation of epigenetically stable antigen-activated Tregs and providing a means for their rapid functional testing in vitro. PMID:29467769

CD137+CD154- Expression As a Regulatory T Cell (Treg)-Specific Activation Signature for Identification and Sorting of Stable Human Tregs from In Vitro Expansion Cultures.

PubMed

Nowak, Anna; Lock, Dominik; Bacher, Petra; Hohnstein, Thordis; Vogt, Katrin; Gottfreund, Judith; Giehr, Pascal; Polansky, Julia K; Sawitzki, Birgit; Kaiser, Andrew; Walter, Jörn; Scheffold, Alexander

2018-01-01

Regulatory T cells (Tregs) are an attractive therapeutic tool for several different immune pathologies. Therapeutic Treg application often requires prolonged in vitro culture to generate sufficient Treg numbers or to optimize their functionality, e.g., via genetic engineering of their antigen receptors. However, purity of clinical Treg expansion cultures is highly variable, and currently, it is impossible to identify and separate stable Tregs from contaminating effector T cells, either ex vivo or after prior expansion. This represents a major obstacle for quality assurance of expanded Tregs and raises significant safety concerns. Here, we describe a Treg activation signature that allows identification and sorting of epigenetically imprinted Tregs even after prolonged in vitro culture. We show that short-term reactivation resulted in expression of CD137 but not CD154 on stable FoxP3+ Tregs that displayed a demethylated Treg-specific demethylated region, high suppressive potential, and lack of inflammatory cytokine expression. We also applied this Treg activation signature for rapid testing of chimeric antigen receptor functionality in human Tregs and identified major differences in the signaling requirements regarding CD137 versus CD28 costimulation. Taken together, CD137+CD154- expression emerges as a universal Treg activation signature ex vivo and upon in vitro expansion allowing the identification and isolation of epigenetically stable antigen-activated Tregs and providing a means for their rapid functional testing in vitro .

Transient Treg depletion enhances therapeutic anti‐cancer vaccination

PubMed Central

Aston, Wayne J.; Chee, Jonathan; Khong, Andrea; Cleaver, Amanda L.; Solin, Jessica N.; Ma, Shaokang; Lesterhuis, W. Joost; Dick, Ian; Holt, Robert A.; Creaney, Jenette; Boon, Louis; Robinson, Bruce; Lake, Richard A.

2016-01-01

Abstract Introduction Regulatory T cells (Treg) play an important role in suppressing anti‐ immunity and their depletion has been linked to improved outcomes. To better understand the role of Treg in limiting the efficacy of anti‐cancer immunity, we used a Diphtheria toxin (DTX) transgenic mouse model to specifically target and deplete Treg. Methods Tumor bearing BALB/c FoxP3.dtr transgenic mice were subjected to different treatment protocols, with or without Treg depletion and tumor growth and survival monitored. Results DTX specifically depleted Treg in a transient, dose‐dependent manner. Treg depletion correlated with delayed tumor growth, increased effector T cell (Teff) activation, and enhanced survival in a range of solid tumors. Tumor regression was dependent on Teffs as depletion of both CD4 and CD8 T cells completely abrogated any survival benefit. Severe morbidity following Treg depletion was only observed, when consecutive doses of DTX were given during peak CD8 T cell activation, demonstrating that Treg can be depleted on multiple occasions, but only when CD8 T cell activation has returned to base line levels. Finally, we show that even minimal Treg depletion is sufficient to significantly improve the efficacy of tumor‐peptide vaccination. Conclusions BALB/c.FoxP3.dtr mice are an ideal model to investigate the full therapeutic potential of Treg depletion to boost anti‐tumor immunity. DTX‐mediated Treg depletion is transient, dose‐dependent, and leads to strong anti‐tumor immunity and complete tumor regression at high doses, while enhancing the efficacy of tumor‐specific vaccination at low doses. Together this data highlight the importance of Treg manipulation as a useful strategy for enhancing current and future cancer immunotherapies. PMID:28250921

Transient Treg depletion enhances therapeutic anti-cancer vaccination.

PubMed

Fisher, Scott A; Aston, Wayne J; Chee, Jonathan; Khong, Andrea; Cleaver, Amanda L; Solin, Jessica N; Ma, Shaokang; Lesterhuis, W Joost; Dick, Ian; Holt, Robert A; Creaney, Jenette; Boon, Louis; Robinson, Bruce; Lake, Richard A

2017-03-01

Regulatory T cells (Treg) play an important role in suppressing anti- immunity and their depletion has been linked to improved outcomes. To better understand the role of Treg in limiting the efficacy of anti-cancer immunity, we used a Diphtheria toxin (DTX) transgenic mouse model to specifically target and deplete Treg. Tumor bearing BALB/c FoxP3.dtr transgenic mice were subjected to different treatment protocols, with or without Treg depletion and tumor growth and survival monitored. DTX specifically depleted Treg in a transient, dose-dependent manner. Treg depletion correlated with delayed tumor growth, increased effector T cell (Teff) activation, and enhanced survival in a range of solid tumors. Tumor regression was dependent on Teffs as depletion of both CD4 and CD8 T cells completely abrogated any survival benefit. Severe morbidity following Treg depletion was only observed, when consecutive doses of DTX were given during peak CD8 T cell activation, demonstrating that Treg can be depleted on multiple occasions, but only when CD8 T cell activation has returned to base line levels. Finally, we show that even minimal Treg depletion is sufficient to significantly improve the efficacy of tumor-peptide vaccination. BALB/c.FoxP3.dtr mice are an ideal model to investigate the full therapeutic potential of Treg depletion to boost anti-tumor immunity. DTX-mediated Treg depletion is transient, dose-dependent, and leads to strong anti-tumor immunity and complete tumor regression at high doses, while enhancing the efficacy of tumor-specific vaccination at low doses. Together this data highlight the importance of Treg manipulation as a useful strategy for enhancing current and future cancer immunotherapies.

The Association of Peripheral Blood Regulatory T-Cell Concentrations With Epithelial Ovarian Cancer: A Brief Report.

PubMed

Cannioto, Rikki A; Sucheston-Campbell, Lara E; Hampras, Shalaka; Goode, Ellen L; Knutson, Keith; Ness, Roberta; Modugno, Francesmary; Wallace, Paul; Szender, J Brian; Mayor, Paul; Hong, Chi-Chen; Joseph, Janine M; Friel, Grace; Davis, Warren; Nesline, Mary; Eng, Kevin H; Edwards, Robert P; Kruszka, Bridget; Schmitt, Kristina; Odunsi, Kunle; Moysich, Kirsten B

2017-01-01

There is a mounting body of evidence demonstrating higher percentages of regulatory T (Treg) cells in the peripheral blood of patients with cancer in comparison to healthy controls, but there is a paucity of epidemiological literature characterizing circulating Treg cells among patients with epithelial ovarian cancer (EOC). To investigate the role of peripheral Treg cells in ovarian neoplasms, we conducted a case-control study to characterize circulating concentrations of Treg cells among patients with EOC, women with benign ovarian conditions, and healthy controls without a history of cancer. Participants were identified for inclusion due to their participation in the Data Bank and BioRepository program at Roswell Park Cancer Institute in Buffalo, NY. Patients included 71 women with a primary diagnosis of EOC and 195 women with a diagnosis of benign ovarian conditions. Controls included 101 age- and race-matched women without a history of cancer. Nonfasting, pretreatment peripheral blood levels of CD3+CD4+CD25+FOXP3+ Treg cells were measured using flow cytometric analyses and expressed as a percentage of total CD3+ cells and as a percentage of total CD3+CD4+ cells. Compared to healthy controls and women with benign ovarian conditions, patients with EOC had significantly higher frequency of Treg cells (P < 0.04). In multivariable logistic regression analyses using Treg frequency expressed as a percentage of CD+3 cells, we observed a significant positive association between Treg cell percentage and EOC risk, with each 1% increase associated with a 37% increased risk of EOC (odds ratio, 1.37; 95% confidence interval, 1.04-1.80). We observed a similar trend when Treg frequency was expressed as a percentage of CD3+CD+4 cells (odds ratio, 1.22; 95% confidence interval, 0.99-1.49). The current study provides support that peripheral Treg cell frequency is elevated in patients with EOC in comparison to women with benign ovarian conditions and healthy controls.

The association of peripheral blood regulatory T-cell concentrations with epithelial ovarian cancer: A brief report

PubMed Central

Hampras, Shalaka; Goode, Ellen L.; Knutson, Keith; Ness, Roberta; Modugno, Francesmary; Wallace, Paul; Szender, J. Brian; Mayor, Paul; Hong, Chi-Chen; Joseph, Janine M.; Friel, Grace; Davis, Warren; Nesline, Mary; Eng, Kevin H.; Edwards, Robert P.; Kruszka, Bridget; Schmitt, Kristina; Odunsi, Kunle; Moysich, Kirsten B.

2016-01-01

Objective There is a mounting body of evidence demonstrating higher percentages of regulatory T (Treg) cells in the peripheral blood of cancer patients in comparison to healthy controls, but there is a paucity of epidemiological literature characterizing circulating Treg cells among epithelial ovarian cancer (EOC) patients. To investigate the role of peripheral Treg cells in ovarian neoplasms, we conducted a case-control study to characterize circulating concentrations of Treg cells among EOC patients, women with benign ovarian conditions, and healthy controls without a history of cancer. Materials and Methods Participants were identified for inclusion due to their participation in the Data Bank and BioRepository program at Roswell Park Cancer Institute in Buffalo, NY. Patients included 71 women with a primary diagnosis of EOC and 195 women with a diagnosis of benign ovarian conditions. Controls included 101 age- and race-matched women without a history of cancer. Non-fasting, pre-treatment peripheral blood levels of CD3+CD4+CD25+FOXP3+ Treg cells were measured using flow cytometric analyses and expressed as a percentage of total CD3+ cells and as a percentage of total CD3+CD4+ cells. Results Compared to healthy controls and women with benign ovarian conditions, EOC patients had significantly higher frequency of Treg cells (p<0.04). In multivariable logistic regression analyses utilizing Treg frequency expressed as a percentage of CD+3 cells, we observed a significant positive association between Treg cell percentage and EOC risk, with each one percent increase associated with a 37% increased risk of EOC (OR=1.37, 95% CI: 1.04-1.80). We observed a similar trend when Treg frequency was expressed as a percentage of CD3+CD+4 cells (OR=1.22, 95% CI: 0.99-1.49). Conclusions The current study provides support that peripheral Treg cell frequency is elevated in EOC patients in comparison to women with benign ovarian conditions and healthy controls. PMID:27759594

TCR signaling by conventional CD4+ T cells is required for optimal maintenance of peripheral regulatory T cell numbers.

PubMed

Leichner, Theresa M; Satake, Atsushi; Kambayashi, Taku

2016-06-01

To maintain immune tolerance, regulatory T cell (Treg) numbers must be closely indexed to the number of conventional T cells (Tconvs) so that an adequate Treg:Tconv ratio can be maintained. Two factors important in this process are the cytokine interleukin-2 (IL-2) and T cell receptor (TCR) stimulation by major histocompatibility complex class II (MHC-II). Here, we report that in addition to TCR stimulation of Tregs themselves, the maintenance of Tregs also requires TCR signaling by Tconvs. We found that Tconvs produce IL-2 in response to self-peptide-MHC-II complexes and that Tconvs possessing more highly self-reactive TCRs express more IL-2 at baseline. Furthermore, selective disruption of TCR signaling in Tconvs led to a trend toward decreased expression of IL-2 and attenuated their ability to maintain Treg numbers. These data suggest that in order to maintain an adequate Treg:Tconv ratio, Tregs are continuously indexed to self-peptide-MHC-II-induced TCR signaling of Tconvs. These results have implications in attempts to modulate immune tolerance, as Treg numbers adjust to the self-reactivity, and ultimately IL-2 production by the T cells around them.

Adoptive Cell Therapy of Induced Regulatory T Cells Expanded by Tolerogenic Dendritic Cells on Murine Autoimmune Arthritis

PubMed Central

Liu, Lidong; Kong, Ning; Jiang, Xueyu; Sun, Juan; Xie, Rufeng

2017-01-01

Objective Tolerogenic dendritic cells (tDCs) can expand TGF-β-induced regulatory T cells (iTregs); however, the therapeutic utility of these expanded iTregs in autoimmune diseases remains unknown. We sought to determine the properties of iTregs expanded by mature tolerogenic dendritic cells (iTregmtDC) in vitro and explore their potential to ameliorate collagen-induced arthritis (CIA) in a mouse model. Methods After induction by TGF-β and expansion by mature tDCs (mtDCs), the phenotype and proliferation of iTregmtDC were assessed by flow cytometry. The ability of iTregs and iTregmtDC to inhibit CD4+ T cell proliferation and suppress Th17 cell differentiation was compared. Following adoptive transfer of iTregs and iTregmtDC to mice with CIA, the clinical and histopathologic scores, serum levels of IFN-γ, TNF-α, IL-17, IL-6, IL-10, TGF-β and anti-CII antibodies, and the distribution of the CD4+ Th subset were assessed. Results Compared with iTregs, iTregmtDC expressed higher levels of Foxp3 and suppressed CD4+ T cell proliferation and Th17 cell differentiation to a greater extent. In vivo, iTregmtDC reduced the severity and progression of CIA more significantly than iTregs, which was associated with a modulated inflammatory cytokine profile, reduced anti-CII IgG levels, and polarized Treg/Th17 balance. Conclusion This study highlights the potential therapeutic utility of iTregmtDC in autoimmune arthritis and should facilitate the future design of iTreg immunotherapeutic strategies. PMID:28702462

Impairment of Circulating CD4⁺CD25⁺GARP⁺ regulatory T cells in patients with acute coronary syndrome.

PubMed

Meng, Kai; Zhang, Wei; Zhong, Yucheng; Mao, Xiaobo; Lin, Yingzhong; Huang, Ying; Lang, Mingjian; Peng, Yudong; Zhu, Zhengfeng; Liu, Yuzhou; Zhao, Xiaoqi; Yu, Kunwu; Wu, Bangwei; Ji, Qingwei; Zeng, Qiutang

2014-01-01

Atherosclerosis (AS) is an inflammatory and immune disease. Regulatory T cells (Tregs) suppress the activation of T cells and have been shown to play a protective role during the pathogenesis of AS. However, specific markers for Tregs are lacking. Recently, glycoprotein A repetitions predominant (GARP) was discovered as a specific marker of activated Tregs, and we therefore utilized GARP as a specific surface marker for Tregs in the current study. To assess whether GARP(+) Tregs are downregulated in patients with acute coronary syndrome (ACS), we examined CD4(+)CD25(+)GARP(+) T cell frequencies as well as their associated cytokines and suppressive function. Additionally, we compared GARP expression to that of FOXP3, which may be more sensitive as a marker of activated Tregs in patients with ACS. Patients with ACS demonstrated a significant decrease in circulating CD4(+)CD25(+)GARP(+) Tregs. Moreover, the suppressive function of Tregs and levels of related cytokines were also impaired in ACS patients compared to those with stable angina (SA) or normal coronary artery (NCA). Additionally, after TCR stimulation, peripheral blood mononuclear cells (PBMCs) from patients with ACS exhibited a decrease in CD4(+)CD25(+)GARP(+) Tregs. These fnding indicate that circulating CD4(+)CD25(+)GARP(+) Tregs are impaired in patients withACS. Thus, targeting GARP may promote the protective function of Tregs in ACS. © 2014 S. Karger AG, Basel.

Expression of a Chimeric Antigen Receptor Specific for Donor HLA Class I Enhances the Potency of Human Regulatory T Cells in Preventing Human Skin Transplant Rejection.

PubMed

Boardman, D A; Philippeos, C; Fruhwirth, G O; Ibrahim, M A A; Hannen, R F; Cooper, D; Marelli-Berg, F M; Watt, F M; Lechler, R I; Maher, J; Smyth, L A; Lombardi, G

2017-04-01

Regulatory T cell (Treg) therapy using recipient-derived Tregs expanded ex vivo is currently being investigated clinically by us and others as a means of reducing allograft rejection following organ transplantation. Data from animal models has demonstrated that adoptive transfer of allospecific Tregs offers greater protection from graft rejection compared to polyclonal Tregs. Chimeric antigen receptors (CAR) are clinically translatable synthetic fusion proteins that can redirect the specificity of T cells toward designated antigens. We used CAR technology to redirect human polyclonal Tregs toward donor-MHC class I molecules, which are ubiquitously expressed in allografts. Two novel HLA-A2-specific CARs were engineered: one comprising a CD28-CD3ζ signaling domain (CAR) and one lacking an intracellular signaling domain (ΔCAR). CAR Tregs were specifically activated and significantly more suppressive than polyclonal or ΔCAR Tregs in the presence of HLA-A2, without eliciting cytotoxic activity. Furthermore, CAR and ΔCAR Tregs preferentially transmigrated across HLA-A2-expressing endothelial cell monolayers. In a human skin xenograft transplant model, adoptive transfer of CAR Tregs alleviated the alloimmune-mediated skin injury caused by transferring allogeneic peripheral blood mononuclear cells more effectively than polyclonal Tregs. Our results demonstrated that the use of CAR technology is a clinically applicable refinement of Treg therapy for organ transplantation. © 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

Signal peptide cleavage is essential for surface expression of a regulatory T cell surface protein, leucine rich repeat containing 32 (LRRC32).

PubMed

Chan, Derek V; Somani, Ally-Khan; Young, Andrew B; Massari, Jessica V; Ohtola, Jennifer; Sugiyama, Hideaki; Garaczi, Edina; Babineau, Denise; Cooper, Kevin D; McCormick, Thomas S

2011-05-26

Elevated numbers of regulatory T cells (T(regs)) have been implicated in certain cancers. Depletion of T(regs) has been shown to increase anti-tumor immunity. T(regs) also play a critical role in the suppression of autoimmune responses. The study of T(regs) has been hampered by a lack of adequate surface markers. Leucine Rich Repeat Containing 32 (LRRC32), also known as Glycoprotein A Repetitions Predominant (GARP), has been postulated as a novel surface marker of activated T(regs). However, there is limited information regarding the processing of LRRC32 or the regulatory phenotype and functional activity of T(regs) expressing LRRC32. Using naturally-occurring freshly isolated T(regs), we demonstrate that low levels of LRRC32 are present intracellularly prior to activation and that freshly isolated LRRC32+ T(regs) are distinct from LRRC32- T(regs) with respect to the expression of surface CD62L. Using LRRC32 transfectants of HEK cells, we demonstrate that the N-terminus of LRRC32 is cleaved prior to expression of the protein at the cell surface. Furthermore, we demonstrate using a construct containing a deleted putative signal peptide region that the presence of a signal peptide region is critical to cell surface expression of LRRC32. Finally, mixed lymphocyte assays demonstrate that LRRC32+ T(regs) are more potent suppressors than LRRC32- T(regs). A cleaved signal peptide site in LRRC32 is necessary for surface localization of native LRRC32 following activation of naturally-occurring freshly-isolated regulatory T cells. LRRC32 expression appears to alter the surface expression of activation markers of T cells such as CD62L. LRRC32 surface expression may be useful as a marker that selects for more potent T(reg) populations. In summary, understanding the processing and expression of LRRC32 may provide insight into the mechanism of action of T(regs) and the refinement of immunotherapeutic strategies aimed at targeting these cells.

Regulatory T cells: Friends or foe in human Mycobacterium leprae infection?

PubMed

Chaves, Ana T; Ribeiro-Junior, Atvaldo F; Lyon, Sandra; Medeiros, Nayara I; Cassirer-Costa, Fábio; Paula, Karina S; Alecrim, Edilamar S; Menezes, Cristiane A S; Correa-Oliveira, Rodrigo; Rocha, Manoel O C; Gomes, Juliana A S

Regulatory T cells (Tregs) are known to control immune responses by suppressing the antigen-presenting and effector T cells. Some mechanisms adopted by Tregs in combating Mycobacterium infections have been proposed. Nevertheless, in M. leprae infection, also known as leprosy or Hansen's disease, the role of Tregs has not been completely elucidated. Using multicolor flow cytometry, we evaluated the expression of different cell surface and intracellular molecules present in Tregs from peripheral blood samples of leprosy patients. Before initiating treatment, thirteen new cases of leprosy were grouped according to the Ridley-Jopling classification in to the paucibacilary (PB) or multibacilary (MB) group. Fifteen non-infected individuals (NI) were included as control subjects. Tregs were higher in the MB group than in the NI group. Tregs also co-expressed high amounts of PD1 and PDL-1, indicating that these cells could induce apoptosis of effector cells and simultaneously prevent their own apoptosis. Our data showed that compared to the NI group, Tregs from the PB group expressed higher levels of CD95L, which may be associated with other apoptotic pathways that may decrease Tregs in these patients. Correlation analysis reinforced that PD1 and CD95L are efficient apoptosis' pathway that decreased levels of Tregs in the NI and PB groups. We also observed significant differences in cytokine expression of Tregs from the PB and MB groups. Compared to the NI group, Tregs from the MB group showed higher IL-17 expression; however, compared to the PB group, the expression of IL-10 in Tregs from the MB group was lower, suggesting inefficient control of inflammation. Therefore, we concluded that different pathways were involved in Treg-induced suppression of leprosy. Moreover, Treg-mediated regulation of inflammation via IL-10 and IL-17 expression in leprosy patients was inefficient. Thus, we propose that during M. leprae infection, Tregs may impair the immune responses elicited against this bacillus, favor bacterial replication, and aid in persistence of a disseminated multibacillary disease. Copyright © 2017 Elsevier GmbH. All rights reserved.

Dendritic Cells Program Non-Immunogenic Prostate-Specific T Cell Responses Beginning at Early Stages of Prostate Tumorigenesis

PubMed Central

Mihalyo, Marianne A.; Hagymasi, Adam T.; Slaiby, Aaron M.; Nevius, Erin E.; Adler, Adam J.

2010-01-01

BACKGROUND Prostate cancer promotes the development of T cell tolerance towards prostatic antigens, potentially limiting the efficacy of prostate cancer vaccines targeting these antigens. Here, we sought to determine the stage of disease progression when T cell tolerance develops, as well as the role of steady state dendritic cells (DC) and CD4+CD25+ T regulatory cells (Tregs) in programming tolerance. METHODS The response of naïve HA-specific CD4+ T cells were analyzed following adoptive transfer into Pro-HA × TRAMP transgenic mice harboring variably-staged HA-expressing prostate tumors on two genetic backgrounds that display different patterns and kinetics of tumorigenesis. The role of DC and Tregs in programming HA-specific CD4 cell responses were assessed via depletion. RESULTS HA-specific CD4 cells underwent non-immunogenic responses at all stages of tumorigenesis in both genetic backgrounds. These responses were completely dependent on DC, but not appreciably influenced by Tregs. CONCLUSIONS These results suggest that tolerogenicity is an early and general property of prostate tumors. PMID:17221844

The IL-33-ST2-MyD88 axis promotes regulatory T cell proliferation in the murine liver.

PubMed

Xu, Lei; Li, Wei; Wang, Xiaofan; Zhang, Lina; Qi, Qianqian; Dong, Liyang; Wei, Chuan; Pu, Yanan; Li, Yalin; Zhu, Jifeng; Zhou, Sha; Liu, Feng; Chen, Xiaojun; Su, Chuan

2018-05-05

Hepatic Foxp3 + regulatory T (Treg) cells are crucial for maintaining local immune homeostasis in the liver. However, the environmental cues required for hepatic Treg cell homeostasis are unclear. In this study, we showed that the IL-33 receptor ST2 was preferentially expressed on Treg cells in the mouse liver, but it was more lowly expressed in the spleen, mesenteric lymph nodes, and blood. More importantly, we found that IL-33 promoted the proliferation of hepatic Treg cells through myeloid differentiation factor MyD88 signaling concomitant with increased CDK4 and cyclin D1 expression. These results suggested that IL-33 is a potential tissue-specific factor controlling Treg cell homeostasis via increased Treg proliferation in the liver. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Genetic and epigenetic variation in the lineage specification of regulatory T cells

PubMed Central

Arvey, Aaron; van der Veeken, Joris; Plitas, George; Rich, Stephen S; Concannon, Patrick; Rudensky, Alexander Y

2015-01-01

Regulatory T (Treg) cells, which suppress autoimmunity and other inflammatory states, are characterized by a distinct set of genetic elements controlling their gene expression. However, the extent of genetic and associated epigenetic variation in the Treg cell lineage and its possible relation to disease states in humans remain unknown. We explored evolutionary conservation of regulatory elements and natural human inter-individual epigenetic variation in Treg cells to identify the core transcriptional control program of lineage specification. Analysis of single nucleotide polymorphisms in core lineage-specific enhancers revealed disease associations, which were further corroborated by high-resolution genotyping to fine map causal polymorphisms in lineage-specific enhancers. Our findings suggest that a small set of regulatory elements specify the Treg lineage and that genetic variation in Treg cell-specific enhancers may alter Treg cell function contributing to polygenic disease. DOI: http://dx.doi.org/10.7554/eLife.07571.001 PMID:26510014

Role of naturally occurring CD4+ CD25+ regulatory T cells in experimental atherosclerosis.

PubMed

Mor, Adi; Planer, David; Luboshits, Galia; Afek, Arnon; Metzger, Shula; Chajek-Shaul, Tova; Keren, Gad; George, Jacob

2007-04-01

Naturally occurring CD4+ CD25+ regulatory T cells (Tregs) exert suppressive effects on effector CD4 cells and downregulate experimental autoimmune disorders. We investigated the importance and potential role of Tregs in murine atherogenesis. Tregs were investigated comparatively between aged and young apolipoprotein E-knockout (ApoE-KO) mice and age-matched C57BL/6 littermates. The effect of oxidized LDL (oxLDL) was tested on the functional suppressive properties of Tregs from ApoE-KO and C57BL/6 mice. Tregs, CD4+ CD25- cells, and saline were infused into ApoE-KO mice to study their effects on atherogenesis. Treg numbers were reduced in atherosclerotic compared with nonatherosclerotic ApoE-KO mice. The functional suppressive properties of Tregs from ApoE-KO mice were compromised in comparison with those from their C57BL/6 littermates. Thus, oxLDL attenuated the suppressive properties of Tregs from C57BL/6 mice and more so in ApoE-KO mice. Transfer of Tregs from age-matched ApoE-KO mice resulted in significant attenuation of atherosclerosis compared with that after delivery of CD4+ CD25+/- T cells or phosphate-buffered saline. CD4+ CD25+ Tregs may play a protective role in the progression of atherosclerosis and could be considered a therapeutic tool if results from human studies can solidify observations in murine models.

A dynamic dual role of IL-2 signaling in the two-step differentiation process of adaptive regulatory T cells.

PubMed

Guo, Zhiyong; Khattar, Mithun; Schroder, Paul M; Miyahara, Yoshihiro; Wang, Guohua; He, Xiaoshung; Chen, Wenhao; Stepkowski, Stanislaw M

2013-04-01

The molecular mechanism of the extrathymic generation of adaptive, or inducible, CD4(+)Foxp3(+) regulatory T cells (iTregs) remains incompletely defined. We show that exposure of splenic CD4(+)CD25(+)Foxp3(-) cells to IL-2, but not other common γ-chain cytokines, resulted in Stat5 phosphorylation and induced Foxp3 expression in ∼10% of the cells. Thus, IL-2/Stat5 signaling may be critical for Foxp3 induction in peripheral CD4(+)CD25(+)Foxp3(-) iTreg precursors. In this study, to further define the role of IL-2 in the formation of iTreg precursors as well as their subsequent Foxp3 expression, we designed a two-step iTreg differentiation model. During the initial "conditioning" step, CD4(+)CD25(-)Foxp3(-) naive T cells were activated by TCR stimulation. Inhibition of IL-2 signaling via Jak3-Stat5 was required during this step to generate CD4(+)CD25(+)Foxp3(-) cells containing iTreg precursors. During the subsequent Foxp3-induction step driven by cytokines, IL-2 was the most potent cytokine to induce Foxp3 expression in these iTreg precursors. This two-step method generated a large number of iTregs with relatively stable expression of Foxp3, which were able to prevent CD4(+)CD45RB(high) cell-mediated colitis in Rag1(-/-) mice. In consideration of this information, whereas initial inhibition of IL-2 signaling upon T cell priming generates iTreg precursors, subsequent activation of IL-2 signaling in these precursors induces the expression of Foxp3. These findings advance the understanding of iTreg differentiation and may facilitate the therapeutic use of iTregs in immune disorders.

S1PR1 is crucial for accumulation of regulatory T cells in tumors via STAT3.

PubMed

Priceman, Saul J; Shen, Shudan; Wang, Lin; Deng, Jiehui; Yue, Chanyu; Kujawski, Maciej; Yu, Hua

2014-03-27

S1PR1 signaling has been shown to restrain the number and function of regulatory T (Treg) cells in the periphery under physiological conditions and in colitis models, but its role in regulating tumor-associated T cells is unknown. Here, we show that S1PR1 signaling in T cells drives Treg accumulation in tumors, limits CD8(+) T cell recruitment and activation, and promotes tumor growth. T-cell-intrinsic S1PR1 affects Treg cells, but not CD8(+) T cells, as demonstrated by adoptive transfer models and transient pharmacological S1PR1 modulation. An increase in S1PR1 in CD4(+) T cells promotes STAT3 activation and JAK/STAT3-dependent Treg tumor migration, whereas STAT3 ablation in T cells diminishes tumor-associated Treg accumulation and tumor growth. Our study demonstrates a stark contrast between the consequences of S1PR1 signaling in Treg cells in the periphery versus tumors. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Critical stoichiometric ratio of CD4(+)  CD25(+)  FoxP3(+) regulatory T cells and CD4(+)  CD25(-) responder T cells influence immunosuppression in patients with B-cell acute lymphoblastic leukaemia.

PubMed

Bhattacharya, Kaushik; Chandra, Sarmila; Mandal, Chitra

2014-05-01

Regulatory T (Treg) cells act to suppress activation of the immune system and thereby maintain immunological homeostasis and tolerance to self-antigens. The frequency and suppressing activity of Treg cells in general are high in different malignancies. We wanted to identify the role and regulation of CD4(+)  CD25(+)  FoxP3(+) Treg cells in B-cell acute lymphoblastic leukaemia (B-ALL). We have included patients at diagnosis (n = 54), patients in clinical remission (n = 32) and normal healthy individuals (n = 35). These diagnosed patients demonstrated a lower number of CD4(+)  CD25(+) cells co-expressing a higher level of FoxP3, interleukin-10, transforming growth factor-β and CD152/CTLA-4 than the normal population. Treg cells from patients showed a higher suppressive capability on CD4(+)  CD25(-) responder T (Tresp) cells than normal. The frequency and immunosuppressive potential of CD4(+)  CD25(+)  FoxP3(+) Treg cells became high with the progression of malignancy in B-ALL. Relative distribution of Tresp and Treg cells was only ~5 : 1 in B-ALL but ~35 : 1 in normal healthy individuals, further confirming the elevated immunosuppression in patients. A co-culture study at these definite ex vivo ratios, indicated that Treg cells from B-ALL patients exhibited higher immunosuppression than Treg cells from normal healthy individuals. After chemotherapy using the MCP841 protocol, the frequency of CD4(+)  CD25(+) cells was gradually enhanced with the reduction of FoxP3, interleukin-10 positivity corresponded with disease presentation, indicating reduced immunosuppression. Taken together, our study indicated that the CD4(+)  CD25(+)  FoxP3(+) Treg cells played an important role in immunosuppression, resulting in a positive disease-correlation in these patients. To the best of our knowledge, this is the first detailed report on the frequency, regulation and functionality of Treg cells in B-ALL. © 2013 John Wiley & Sons Ltd.

Single and combined effect of retinoic acid and rapamycin modulate the generation, activity and homing potential of induced human regulatory T cells

PubMed Central

Candia, Enzo; Reyes, Paz; Covian, Camila; Rodriguez, Francisco; Wainstein, Nicolas; Morales, Jorge; Mosso, Claudio; Rosemblatt, Mario

2017-01-01

Adoptive transfer of CD4+CD25+FOXP3+ regulatory T cells (Treg cells) has been successfully utilized to treat graft versus host disease and represents a promising strategy for the treatment of autoimmune diseases and transplant rejection. The aim of this study was to evaluate the effects of all-trans retinoic acid (atRA) and rapamycin (RAPA) on the number, phenotype, homing markers expression, DNA methylation, and function of induced human Treg cells in short-term cultures. Naive T cells were polyclonally stimulated and cultured for five days in the presence of different combinations of IL-2, TGF-β1, atRA and RAPA. The resulting cells were characterized by the expression of FOXP3, activation, surface and homing markers. Methylation of the Conserved Non-coding Sequence 2 was also evaluated. Functional comparison of the different culture conditions was performed by suppression assays in vitro. Culturing naive human T cells with IL-2/TGFβ1 resulted in the generation of 54.2% of Treg cells (CD4+CD25+FOXP3+) whereas the addition of 100 nM atRA increased the yield of Treg cells to 66% (p = 0.0088). The addition of RAPA did not increase the number of Treg cells in any of these settings. Treg cells generated in the presence of atRA had an increased expression of the β7 integrin to nearly 100% of the generated Treg cells, while RAPA treated cells showed enhanced expression of CXCR4. The differential expression of homing molecules highlights the possibility of inducing Treg cells with differential organ-specific homing properties. Neither atRA nor RAPA had an effect on the highly methylated CNS2 sites, supporting reports that their contribution to the lineage stability of Treg cells is not mediated by methylation changes in this locus. Treg cells generated in the presence of RAPA show the most potent suppression effect on the proliferation of effector cells. PMID:28746369

S1PR1 is crucial for accumulation of regulatory T cells in tumors via STAT3

PubMed Central

Priceman, Saul J.; Shen, Shudan; Wang, Lin; Deng, Jiehui; Yue, Chanyu; Kujawski, Maciej; Yu, Hua

2014-01-01

Summary S1PR1 signaling has been shown to restrain the number and function of Tregs in the periphery under physiological conditions and in colitis models, but its role in regulating tumor-associated T cells is unknown. Here, we show that S1PR1 signaling in T cells drives Treg accumulation in tumors, limits CD8+ T cell recruitment and activation, and promotes tumor growth. S1PR1 intrinsic in T cells affects Tregs, but not CD8+ T cells, as demonstrated by adoptive transfer models and transient pharmacological S1PR1 modulation. We further investigated the molecular mechanism(s) underlying S1PR1-mediated Treg accumulation in tumors, showing that increasing S1PR1 in CD4+ T cells promotes STAT3 activation and JAK/STAT3-dependent Treg tumor migration. Furthermore functionally ablating STAT3 in T cells diminishes tumor-associated Treg accumulation and tumor growth. Our study demonstrates a stark contrast of the consequences by the same signaling receptor, namely S1PR1, in regulating Tregs in the periphery and in tumors. PMID:24630990

Increasing regulatory T cells with interleukin-2 and interleukin-2 antibody complexes attenuates lung inflammation and heart failure progression

PubMed Central

Wang, Huan; Hou, Lei; Kwak, Dongmin; Fassett, John; Xu, Xin; Chen, Angela; Chen, Wei; Blazar, Bruce R.; Xu, Yawei; Hall, Jennifer L.; Ge, Jun-bo; Bache, Robert J.; Chen, Yingjie

2016-01-01

Congestive heart failure (CHF) is associated with an increase of leukocyte infiltration, pro-inflammatory cytokines and fibrosis in the heart and lung. Regulatory T cells (Tregs, CD4+CD25+FoxP3+) suppress inflammatory responses in various clinical conditions. We postulated that expansion of Tregs attenuates CHF progression by reducing cardiac and lung inflammation. We investigated the effects of Interleukin-2 (IL-2) plus IL-2 monoclonal antibody clone JES6-1 complexes (IL2/JES6-1) on induction of Tregs, transverse aortic constriction (TAC)-induced cardiac and lung inflammation and CHF progression in mice. We demonstrated that end-stage CHF caused a massive increase of lung macrophages and T cells, as well as relatively mild LV leukocyte infiltration. Administration of IL2/JES6-1 caused a ~6-fold increase of Tregs within CD4+ T cells in the spleen, lung and heart of mice. IL2/JES6-1 treatment of mice with existing TAC-induced left ventricular (LV) failure markedly reduced lung and right ventricular (RV) weight, and improved LV ejection fraction and LV end-diastolic pressure. Mechanistically, IL2/JES6-1 treatment significantly increased Tregs, suppressed CD4+ T-cell accumulation, dramatically attenuated leukocyte infiltration including decreasing CD45+ cells, macrophages, CD8+ T cells and effector memory CD8+, and reduced pro-inflammatory cytokine expressions and fibrosis in the lung of mice. Furthermore, IL2/JES6-1 administered before TAC attenuated the development of LV hypertrophy and dysfunction in mice. Our data indicate that increasing Tregs through administration of IL2/JES6-1 effectively attenuates pulmonary inflammation, RV hypertrophy and further LV dysfunction in mice with existing LV failure, suggesting strategies to properly expand Tregs may be useful in reducing CHF progression. PMID:27160197

Treatment with agonistic DR3 antibody results in expansion of donor Tregs and reduced graft-versus-host disease

PubMed Central

Kim, Byung-Su; Nishikii, Hidekazu; Baker, Jeanette; Pierini, Antonio; Schneidawind, Dominik; Pan, Yuqiong; Beilhack, Andreas; Park, Chung-Gyu

2015-01-01

The paucity of regulatory T cells (Tregs) limits clinical translation to control aberrant immune reactions including graft-versus-host disease (GVHD). Recent studies showed that the agonistic antibody to DR3 (αDR3) expanded CD4+FoxP3+ Tregs in vivo. We investigated whether treating donor mice with a single dose of αDR3 could alleviate acute GVHD in a MHC-mismatched bone marrow transplantation model. αDR3 induced selective proliferation of functional Tregs. CD4+ T cells isolated from αDR3-treated mice contained higher numbers of Tregs and were less proliferative to allogeneic stimuli. In vivo GVHD studies confirmed that Tregs from αDR3-treated donors expanded robustly and higher frequencies of Tregs within donor CD4+ T cells were maintained, resulting in improved survival. Conventional T cells derived from αDR3-treated donors showed reduced activation and proliferation. Serum levels of proinflammatory cytokines (IFNγ, IL-1β, and TNFα) and infiltration of donor T cells into GVHD target tissues (gastrointestinal tract and liver) were decreased. T cells from αDR3-treated donors retained graft-vs-tumor (GVT) effects. In conclusion, a single dose of αDR3 alleviates acute GVHD while preserving GVT effects by selectively expanding and maintaining donor Tregs. This novel strategy will facilitate the clinical application of Treg-based therapies. PMID:26063163

Garp as a therapeutic target for modulation of T regulatory cell function.

PubMed

Shevach, Ethan M

2017-02-01

Foxp3 + T regulatory cells (Tregs) play critical roles in immune homeostasis primarily by suppressing many aspects of the immune response. Tregs uniquely express GARP on their cell surface and GARP functions as a delivery system for latent TGF-β. As Treg-derived TGF-β may mediate the suppressive functions of Tregs, GARP may represent a target to inhibit Treg suppression in cancer or augment suppression in autoimmunity. Areas covered: This article will focus on 1) the role of Treg-derived TGF-β in the suppressive activity of Treg, 2) the cellular and molecular regulation of expression of GARP on mouse and human Tregs, 3) the role of integrins in the activation of latent-TGF-β/GARP complex, 4) an overview of our present understanding of the function of the latent-TGF-β/GARP complex. Expert opinion: Two approaches are outlined for targeting the L-TGF-β1/GARP complex for therapeutic purposes. Tregs play a major role in suppressive effector T cell responses to tumors and TGF-β1 may be a major contributor to this process. One approach is to specifically block the production of active TGF-β1 from Tregs as an adjunct to tumor immunotherapy. The second approach in autoimmunity is to selectively enhance the production of TGF-β by Tregs at sites of chronic inflammation.

microRNA-342, microRNA-191 and microRNA-510 are differentially expressed in T regulatory cells of type 1 diabetic patients.

PubMed

Hezova, Renata; Slaby, Ondrej; Faltejskova, Petra; Mikulkova, Zuzana; Buresova, Ivana; Raja, K R Muthu; Hodek, Jan; Ovesna, Jaroslava; Michalek, Jaroslav

2010-01-01

Regulatory T cells (Tregs) are critical regulators of autoimmune diseases, including type 1 diabetes mellitus. It is hypothesised that Tregs' function can be influenced by changes in the expression of specific microRNAs (miRNAs). Thus, we performed miRNAs profiling in a population of Tregs separated from peripheral blood of five type 1 diabetic patients and six healthy donors. For more detailed molecular characterisation of Tregs, we additionally compared miRNAs expression profiles of Tregs and conventional T cells. Tregs were isolated according to CD3+, CD4+, CD25(hi)+ and CD127- by flow cytometry, and miRNA expression profiling was performed using TaqMan Array Human MicroRNA Panel-1 (384-well low density array). In Tregs of diabetic patients we found significantly increased expression of miRNA-510 (p=0.05) and decreased expression of both miRNA-342 (p<0.0001) and miRNA-191 (p=0.0079). When comparing Tregs and T cells, we revealed that Tregs had significant higher expression of miRNA-146a and lower expression of eight specific miRNAs (20b, 31, 99a, 100, 125b, 151, 335, and 365). To our knowledge, this is the first study demonstrating changes in miRNA expression profiles occurring in Tregs of T1D patients and a miRNAs signature of adult Tregs.

Phosphoproteomics Reveals Regulatory T Cell-Mediated DEF6 Dephosphorylation That Affects Cytokine Expression in Human Conventional T Cells

PubMed Central

Joshi, Rubin N.; Binai, Nadine A.; Marabita, Francesco; Sui, Zhenhua; Altman, Amnon; Heck, Albert J. R.; Tegnér, Jesper; Schmidt, Angelika

2017-01-01

Regulatory T cells (Tregs) control key events of immune tolerance, primarily by suppression of effector T cells. We previously revealed that Tregs rapidly suppress T cell receptor (TCR)-induced calcium store depletion in conventional CD4+CD25− T cells (Tcons) independently of IP3 levels, consequently inhibiting NFAT signaling and effector cytokine expression. Here, we study Treg suppression mechanisms through unbiased phosphoproteomics of primary human Tcons upon TCR stimulation and Treg-mediated suppression, respectively. Tregs induced a state of overall decreased phosphorylation as opposed to TCR stimulation. We discovered novel phosphosites (T595_S597) in the DEF6 (SLAT) protein that were phosphorylated upon TCR stimulation and conversely dephosphorylated upon coculture with Tregs. Mutation of these DEF6 phosphosites abrogated interaction of DEF6 with the IP3 receptor and affected NFAT activation and cytokine transcription in primary Tcons. This novel mechanism and phosphoproteomics data resource may aid in modifying sensitivity of Tcons to Treg-mediated suppression in autoimmune disease or cancer. PMID:28993769

CD4+CD25+ regulatory T cells suppress mast cell degranulation and allergic responses through OX40-OX40L interaction

PubMed Central

Gri, Giorgia; Piconese, Silvia; Frossi, Barbara; Manfroi, Vanessa; Merluzzi, Sonia; Tripodo, Claudio; Viola, Antonella; Odom, Sandra; Rivera, Juan; Colombo, Mario P.; Pucillo, Carlo E.

2008-01-01

Summary CD4+CD25+ T regulatory cells (Tregs) play a central role in the suppression of immune responses thus serving to induce tolerance and to control persistent immune responses that can lead to autoimmunity. Here we explore if Tregs also play a role in controlling the immediate hypersensitivity response of mast cells (MCs). Tregs directly inhibit the FcεRI-dependent degranulation of MCs through cell-cell contact involving OX40-OX40L interactions between Tregs and MCs, respectively. MCs show increased cAMP levels and reduced Ca2+ influx, independent of PLC-γ2 or Ca2+ release from intracellular stores. Antagonism of cAMP in MCs reverses the inhibitory effects of Tregs restoring normal Ca2+ responses and degranulation. Importantly, the in vivo depletion or inactivation of Tregs causes enhancement of the anaphylactic response. The demonstrated cross-talk between Tregs and MCs defines a previously unrecognized mechanism controlling MCs degranulation. Loss of this interaction may contribute to the severity of allergic responses. PMID:18993084

Extrathymic generation of regulatory T cells in placental mammals mitigates maternal-fetal conflict.

PubMed

Samstein, Robert M; Josefowicz, Steven Z; Arvey, Aaron; Treuting, Piper M; Rudensky, Alexander Y

2012-07-06

Regulatory T (Treg) cells, whose differentiation and function are controlled by X chromosome-encoded transcription factor Foxp3, are generated in the thymus (tTreg) and extrathymically (peripheral, pTreg), and their deficiency results in fatal autoimmunity. Here, we demonstrate that a Foxp3 enhancer, conserved noncoding sequence 1 (CNS1), essential for pTreg but dispensable for tTreg cell generation, is present only in placental mammals. CNS1 is largely composed of mammalian-wide interspersed repeats (MIR) that have undergone retrotransposition during early mammalian radiation. During pregnancy, pTreg cells specific to a model paternal alloantigen were generated in a CNS1-dependent manner and accumulated in the placenta. Furthermore, when mated with allogeneic, but not syngeneic, males, CNS1-deficient females showed increased fetal resorption accompanied by increased immune cell infiltration and defective remodeling of spiral arteries. Our results suggest that, during evolution, a CNS1-dependent mechanism of extrathymic differentiation of Treg cells emerged in placental animals to enforce maternal-fetal tolerance. Copyright © 2012 Elsevier Inc. All rights reserved.

In vivo kinetics and nonradioactive imaging of rapidly proliferating cells in graft-versus-host disease

PubMed Central

Buxbaum, Nataliya P.; Farthing, Donald E.; Maglakelidze, Natella; Lizak, Martin; Merkle, Hellmut; Carpenter, Andrea C.; Oliver, Brittany U.; Kapoor, Veena; Castro, Ehydel; Swan, Gregory A.; dos Santos, Liliane M.; Bouladoux, Nicolas J.; Bare, Catherine V.; Flomerfelt, Francis A.; Eckhaus, Michael A.; Telford, William G.; Belkaid, Yasmine; Bosselut, Remy J.; Gress, Ronald E.

2017-01-01

Hematopoietic stem cell transplantation (HSCT) offers a cure for cancers that are refractory to chemotherapy and radiation. Most HSCT recipients develop chronic graft-versus-host disease (cGVHD), a systemic alloimmune attack on host organs. Diagnosis is based on clinical signs and symptoms, as biopsies are risky. T cells are central to the biology of cGVHD. We found that a low Treg/CD4+ T effector memory (Tem) ratio in circulation, lymphoid, and target organs identified early and established mouse cGVHD. Using deuterated water labeling to measure multicompartment in vivo kinetics of these subsets, we show robust Tem and Treg proliferation in lymphoid and target organs, while Tregs undergo apoptosis in target organs. Since deuterium enrichment into DNA serves as a proxy for cell proliferation, we developed a whole-body clinically relevant deuterium MRI approach to nonradioactively detect cGVHD and potentially allow imaging of other diseases characterized by rapidly proliferating cells. PMID:28614804

A novel IL-10-independent regulatory role for B cells in suppressing autoimmunity by maintenance of regulatory T cells via GITR ligand.

PubMed

Ray, Avijit; Basu, Sreemanti; Williams, Calvin B; Salzman, Nita H; Dittel, Bonnie N

2012-04-01

B cells are important for the regulation of autoimmune responses. In experimental autoimmune encephalomyelitis (EAE), B cells are required for spontaneous recovery in acute models. Production of IL-10 by regulatory B cells has been shown to modulate the severity EAE and other autoimmune diseases. Previously, we suggested that B cells regulated the number of CD4(+)Foxp3(+) T regulatory cells (Treg) in the CNS during EAE. Because Treg suppress autoimmune responses, we asked whether B cells control autoimmunity by maintenance of Treg numbers. B cell deficiency achieved either genetically (μMT) or by depletion with anti-CD20 resulted in a significant reduction in the number of peripheral but not thymic Treg. Adoptive transfer of WT B cells into μMT mice restored both Treg numbers and recovery from EAE. When we investigated the mechanism whereby B cells induce the proliferation of Treg and EAE recovery, we found that glucocorticoid-induced TNF ligand, but not IL-10, expression by B cells was required. Of clinical significance is the finding that anti-CD20 depletion of B cells accelerated spontaneous EAE and colitis. Our results demonstrate that B cells play a major role in immune tolerance required for the prevention of autoimmunity by maintenance of Treg via their expression of glucocorticoid-induced TNFR ligand.

Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID.

PubMed

Sauer, Aisha V; Brigida, Immacolata; Carriglio, Nicola; Hernandez, Raisa Jofra; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna; Aiuti, Alessandro

2012-02-09

Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)-mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA-treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA(-/-) Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA-treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA-treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID.

Conferring indirect allospecificity on CD4+CD25+ Tregs by TCR gene transfer favors transplantation tolerance in mice

PubMed Central

Tsang, Julia Yuen-Shan; Tanriver, Yakup; Jiang, Shuiping; Xue, Shao-An; Ratnasothy, Kulachelvy; Chen, Daxin; Stauss, Hans J.; Bucy, R. Pat; Lombardi, Giovanna; Lechler, Robert

2008-01-01

T cell responses to MHC-mismatched transplants can be mediated via direct recognition of allogeneic MHC molecules on the cells of the transplant or via recognition of allogeneic peptides presented on the surface of recipient APCs in recipient MHC molecules — a process known as indirect recognition. As CD4+CD25+ Tregs play an important role in regulating alloresponses, we investigated whether mouse Tregs specific for allogeneic MHC molecules could be generated in vitro and could promote transplantation tolerance in immunocompetent recipient mice. Tregs able to directly recognize allogeneic MHC class II molecules (dTregs) were obtained by stimulating CD4+CD25+ cells from C57BL/6 mice (H-2b) with allogeneic DCs from BALB/c mice (H-2d). To generate Tregs that indirectly recognized allogeneic MHC class II molecules, dTregs were retrovirally transduced with TCR genes conferring specificity for H-2Kd presented by H-2Ab MHC class II molecules. The dual direct and indirect allospecificity of the TCR-transduced Tregs was confirmed in vitro. In mice, TCR-transduced Tregs, but not dTregs, induced long-term survival of partially MHC-mismatched heart grafts when combined with short-term adjunctive immunosuppression. Further, although dTregs were only slightly less effective than TCR-transduced Tregs at inducing long-term survival of fully MHC-mismatched heart grafts, histologic analysis of long-surviving hearts demonstrated marked superiority of the TCR-transduced Tregs. Thus, Tregs specific for allogeneic MHC class II molecules are effective in promoting transplantation tolerance in mice, which suggests that such cells have clinical potential. PMID:18846251

IL233, A Novel IL-2 and IL-33 Hybrid Cytokine, Ameliorates Renal Injury.

PubMed

Stremska, Marta E; Jose, Sheethal; Sabapathy, Vikram; Huang, Liping; Bajwa, Amandeep; Kinsey, Gilbert R; Sharma, Poonam R; Mohammad, Saleh; Rosin, Diane L; Okusa, Mark D; Sharma, Rahul

2017-09-01

CD4 + Foxp3 + regulatory T cells (Tregs) protect the kidney during AKI. We previously found that IL-2, which is critical for Treg homeostasis, upregulates the IL-33 receptor (ST2) on CD4 + T cells, thus we hypothesized that IL-2 and IL-33 cooperate to enhance Treg function. We found that a major subset of Tregs in mice express ST2, and coinjection of IL-2 and IL-33 increased the number of Tregs in lymphoid organs and protected mice from ischemia-reperfusion injury (IRI) more efficiently than either cytokine alone. Accordingly, we generated a novel hybrid cytokine (IL233) bearing the activities of IL-2 and IL-33 for efficient targeting to Tregs. IL233 treatment increased the number of Tregs in blood and spleen and prevented IRI more efficiently than a mixture of IL-2 and IL-33. Injection of IL233 also increased the numbers of Tregs in renal compartments. Moreover, IL233-treated mice had fewer splenic Tregs and more Tregs in kidneys after IRI. In vitro , splenic Tregs from IL233-treated mice suppressed CD4 + T cell proliferation better than Tregs from saline-treated controls. IL233 treatment also improved the ability of isolated Tregs to inhibit IRI in adoptive transfer experiments and protected mice from cisplatin- and doxorubicin-induced nephrotoxic injury. Finally, treatment with IL233 increased the proportion of ST2-bearing innate lymphoid cells (ILC2) in blood and kidneys, and adoptive transfer of ILC2 also protected mice from IRI. Thus, the novel IL233 hybrid cytokine, which utilizes the cooperation of IL-2 and IL-33 to enhance Treg- and ILC2-mediated protection from AKI, bears strong therapeutic potential. Copyright © 2017 by the American Society of Nephrology.

IFNγ Signaling Endows DCs with the Capacity to Control Type I Inflammation during Parasitic Infection through Promoting T-bet+ Regulatory T Cells

PubMed Central

Lee, Hyang-Mi; Fleige, Anne; Forman, Ruth; Cho, Sunglim; Khan, Aly Azeem; Lin, Ling-Li; Nguyen, Duc T.; O'Hara-Hall, Aisling; Yin, Zhinan; Hunter, Christopher A.; Muller, Werner; Lu, Li-Fan

2015-01-01

IFNγ signaling drives dendritic cells (DCs) to promote type I T cell (Th1) immunity. Here, we show that activation of DCs by IFNγ is equally crucial for the differentiation of a population of T-bet+ regulatory T (Treg) cells specialized to inhibit Th1 immune responses. Conditional deletion of IFNγ receptor in DCs but not in Treg cells resulted in a severe defect in this specific Treg cell subset, leading to exacerbated immune pathology during parasitic infections. Mechanistically, IFNγ-unresponsive DCs failed to produce sufficient amount of IL-27, a cytokine required for optimal T-bet induction in Treg cells. Thus, IFNγ signalling endows DCs with the ability to efficiently control a specific type of T cell immunity through promoting a corresponding Treg cell population. PMID:25658840

Co-expression of LAG3 and TIM3 identifies a potent Treg population that suppresses macrophage functions in colorectal cancer patients.

PubMed

Ma, Qiang; Liu, Junning; Wu, Guoliang; Teng, Mujian; Wang, Shaoxuan; Cui, Meng; Li, Yuantao

2018-06-15

Regulatory T (Treg) cells are critical suppressors of inflammation and are thought to exert mainly deleterious effects in cancers. In colorectal cancer (CRC), Foxp3 +  Treg accumulation in the tumor was associated with poor prognosis. Hence, we examined the circulating Treg cells in CRC patients. Compared to controls, CRC patients presented mild upregulations in CD4 + CD25 +/hi T cells and in the more canonical CD4 + CD25 +/hi Foxp3 + Treg cells in peripheral blood mononuclear cells. Both of these Treg populations could be roughly divided into LAG3 - TIM3 - and LAG3 + TIM3 + subsets. In CRC patients, the LAG3 + TIM3 + subset represented approximately half of CD4 + CD25 +/hi T cells and greater than 60% of CD4 + CD25 +/hi Foxp3 + Treg cells, which was significantly more frequent than in healthy controls. Compared to the LAG3 - TIM3 - CD4 + CD25 +/hi T cells, the LAG3 + TIM3 + CD4 + CD25 +/hi T cells presented considerably higher transforming growth factor (TGF)-β and slightly higher interleukin (IL)-10 secretion, together with higher CTLA-4 and Foxp3 expression levels. Notably, macrophages following incubation with LAG3 - TIM3 - CD4 + CD25 +/hi T cells and LAG3 + TIM3 + CD4 + CD25 +/hi T cells displayed different characteristics. Macrophages incubated with LAG3 + TIM3 + CD4 + CD25 +/hi T cells presented lower expression of MHC class II, CD80, CD86, and tumor necrosis factor alpha (TNFα) but higher expression of IL-10, than macrophages incubated with LAG3 - TIM3 - CD4 + CD25 +/hi T cells. Together, our investigations demonstrated that CRC patients presented an enrichment of circulating Treg cells, in which the LAG3 + TIM3 + subset exhibited more potent expression of inhibitory molecules, and furthermore, the LAG3 + TIM3 + Treg cells could suppress the proinflammatory activation of macrophages more potently than the LAG3 - TIM3 - Treg cells. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Release of active TGF-β1 from the Latent TGF-β1/GARP complex on T regulatory cells is mediated by Integrin β81

PubMed Central

Edwards, Justin P.; Thornton, Angela M.; Shevach, Ethan M.

2014-01-01

Activated T regulatory cells (Treg) express latent TGF-β1 on their cell surface bound to GARP. Although integrins have been implicated in mediating the release of active TGF-β1 from the complex of latent TGF-β1 and latent TGF-β1 binding protein, their role in processing latent TGF-β1 from the latent TGF-β1/GARP complex is unclear. Mouse CD4+Foxp3+ Treg, but not CD4+Foxp3− T cells, expressed integrin β8 (Itgb8) as detected by qRT-PCR. Itgb8 expression was a marker of thymically-derived (t)Treg, as it could not be detected on Foxp3+Helios− Tregs or on Foxp3+ T cells induced in vitro. Tregs from Itgb8 conditional knockouts exhibited normal suppressor function in vitro and in vivo in a model of colitis, but failed to provide TGF-β1 to drive Th17 or iTreg differentiation in vitro. In addition, Itgb8 knockout Tregs expressed higher levels of latent TGF-β1 on their cell surface consistent with defective processing. Thus, integrin αvβ8 is a marker of tTregs and functions in a cell intrinsic manner in mediating the processing of latent TGF-β1 from the latent TGF-β1/GARP complex on the surface of tTregs. PMID:25127859

CTLA-4+ Regulatory T Cells Increased in Cetuximab Treated Head and Neck Cancer Patients Suppress NK Cell Cytotoxicity and Correlate with Poor Prognosis

PubMed Central

Jie, Hyun-Bae; Schuler, Patrick J.; Lee, Steve C.; Srivastava, Raghvendra M.; Argiris, Athanassios; Ferrone, Soldano; Whiteside, Theresa L.; Ferris, Robert L.

2015-01-01

The EGFR-targeted antibody cetuximab is effective against head and neck cancer (HNC), but in only 15 – 20% of patients, and the variability and extent of cetuximab-mediated cellular immunity is not fully understood. We hypothesized that regulatory T cells (Treg) may exert a functional and clinical impact on antitumor immunity in cetuximab-treated individuals. The frequency, immunosuppressive phenotype and activation status of Treg and NK cells were analyzed in the circulation and tumor microenvironment of cetuximab-treated HNC patients enrolled in a novel neoadjuvant, single-agent cetuximab clinical trial. Notably, cetuximab treatment increased the frequency of CD4+FOXP3+ intratumoral Treg expressing CTLA-4, CD39 and TGF-β. These Treg suppressed cetuximab-mediated ADCC and their presence correlated with poor clinical outcome in two prospective clinical trial cohorts. Cetuximab expanded CTLA-4+FOXP3+ Treg in vitro, in part by inducing DC maturation, in combination with TGF-β and TCR triggering. Importantly, cetuximab-activated NK cells selectively eliminated intratumoral Treg but preserved effector T cells. In ex vivo assays, ipilimumab targeted CTLA-4+ Treg and restored cytolytic functions of NK cells mediating ADCC. Taken together, our results argue that differences in Treg-mediated suppression contribute to the clinical response to cetuximab treatment, suggesting its improvement by adding ipilimumab or other strategies of Treg ablation to promote anti-tumor immunity. PMID:25832655

Leptin directly promotes T-cell glycolytic metabolism to drive effector T-cell differentiation in a mouse model of autoimmunity.

PubMed

Gerriets, Valerie A; Danzaki, Keiko; Kishton, Rigel J; Eisner, William; Nichols, Amanda G; Saucillo, Donte C; Shinohara, Mari L; MacIver, Nancie J

2016-08-01

Upon activation, T cells require energy for growth, proliferation, and function. Effector T (Teff) cells, such as Th1 and Th17 cells, utilize high levels of glycolytic metabolism to fuel proliferation and function. In contrast, Treg cells require oxidative metabolism to fuel suppressive function. It remains unknown how Teff/Treg-cell metabolism is altered when nutrients are limited and leptin levels are low. We therefore examined the role of malnutrition and associated hypoleptinemia on Teff versus Treg cells. We found that both malnutrition-associated hypoleptinemia and T cell-specific leptin receptor knockout suppressed Teff-cell number, function, and glucose metabolism, but did not alter Treg-cell metabolism or suppressive function. Using the autoimmune mouse model EAE, we confirmed that fasting-induced hypoleptinemia altered Teff-cell, but not Treg-cell, glucose metabolism, and function in vivo, leading to decreased disease severity. To explore potential mechanisms, we examined HIF-1α, a key regulator of Th17 differentiation and Teff-cell glucose metabolism, and found HIF-1α expression was decreased in T cell-specific leptin receptor knockout Th17 cells, and in Teff cells from fasted EAE mice, but was unchanged in Treg cells. Altogether, these data demonstrate a selective, cell-intrinsic requirement for leptin to upregulate glucose metabolism and maintain function in Teff, but not Treg cells. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Norisoboldine, a natural AhR agonist, promotes Treg differentiation and attenuates colitis via targeting glycolysis and subsequent NAD+/SIRT1/SUV39H1/H3K9me3 signaling pathway.

PubMed

Lv, Qi; Wang, Kai; Qiao, Simiao; Yang, Ling; Xin, Yirong; Dai, Yue; Wei, Zhifeng

2018-02-15

Norisoboldine (NOR), a natural aryl hydrocarbon receptor (AhR) agonist, has been demonstrated to attenuate ulcerative colitis (UC) and induce the generation of Treg cells. Under UC condition, hypoxia widely exists in colonic mucosa, and secondary changes of microRNAs (miRs) expressions and glycolysis contribute to Treg differentiation. At present, we worked for exploring the deep mechanisms for NOR-promoted Treg differentiation in hypoxia and its subsequent anti-UC action from the angle of AhR/miR or AhR/glycolysis axis. Results showed that NOR promoted Treg differentiation in hypoxia and the effect was stronger relative to normoxia. It activated AhR in CD4 + T cells under hypoxic microenvironment; CH223191 (a specific AhR antagonist) and siAhR-3 abolished NOR-promoted Treg differentiation. Furthermore, the progress of glycolysis, levels of Glut1 and HK2, and expression of miR-31 rather than miR-219 and miR-490 in CD4 + T cells were downregulated by NOR treatment under hypoxic microenvironment. However, HK2 plasmid but not miR-31 mimic significantly interfered NOR-enhanced Treg polarization. In addition, NOR reduced NAD + and SIRT1 levels, facilitated the ubiquitin-proteasomal degradation of SUV39H1 protein, and inhibited the enrichment of H3K9me3 at -1, 201 to -1,500 region of Foxp3 promoter in CD4 + T cells under hypoxic microenvironment, which was weakened by HK2 plasmid, CH223191, and siAhR-3. Finally, the correlation between NOR-mediated activation of AhR, repression of glycolysis, regulation of NAD + /SIRT1/SUV39H1/H3K9me3 signals, induction of Treg cells, and remission of colitis was confirmed in mice with DSS-induced colitis by using CH223191 and HK2 plasmid. In conclusion, NOR promoted Treg differentiation and then alleviated the development of colitis by regulating AhR/glycolysis axis and subsequent NAD + /SIRT1/SUV39H1/H3K9me3 signaling pathway.

Regulatory T cells accumulate and proliferate in the ischemic hemisphere for up to 30 days after MCAO

PubMed Central

Stubbe, Tobias; Ebner, Friederike; Richter, Daniel; Randolf Engel, Odilo; Klehmet, Juliane; Royl, Georg; Meisel, Andreas; Nitsch, Robert; Meisel, Christian; Brandt, Christine

2013-01-01

Local and peripheral immune responses are activated after ischemic stroke. In our present study, we investigated the temporal distribution, location, induction, and function of regulatory T cells (Tregs) and the possible involvement of microglia, macrophages, and dendritic cells after middle cerebral artery occlusion (MCAO). C57BL/6J and Foxp3EGFP transgenic mice were subjected to 30 minutes MCAO. On days 7, 14, and 30 after MCAO, Tregs and antigen presenting cells were analyzed using fluorescence activated cell sorting multicolor staining and immunohistochemistry. A strong accumulation of Tregs was observed on days 14 and 30 in the ischemic hemisphere accompanied by the elevated presence and activation of microglia. Dendritic cells and macrophages were found on each analyzed day. About 60% of Foxp3+ Tregs in ischemic hemispheres were positive for the proliferation marker Ki-67 on days 7 and 14 after MCAO. The transfer of naive CD4+ cells depleted of Foxp3+ Tregs into RAG1−/− mice 1 day before MCAO did not lead to a de novo generation of Tregs 14 days after surgery. After depletion of CD25+ Tregs, no changes regarding neurologic outcome were detected. The sustained presence of Tregs in the brain after MCAO indicates a long-lasting immunological alteration and involvement of brain cells in immunoregulatory mechanisms. PMID:22968321

Regulatory T cells accumulate and proliferate in the ischemic hemisphere for up to 30 days after MCAO.

PubMed

Stubbe, Tobias; Ebner, Friederike; Richter, Daniel; Engel, Odilo; Randolf Engel, Odilo; Klehmet, Juliane; Royl, Georg; Meisel, Andreas; Nitsch, Robert; Meisel, Christian; Brandt, Christine

2013-01-01

Local and peripheral immune responses are activated after ischemic stroke. In our present study, we investigated the temporal distribution, location, induction, and function of regulatory T cells (Tregs) and the possible involvement of microglia, macrophages, and dendritic cells after middle cerebral artery occlusion (MCAO). C57BL/6J and Foxp3(EGFP) transgenic mice were subjected to 30 minutes MCAO. On days 7, 14, and 30 after MCAO, Tregs and antigen presenting cells were analyzed using fluorescence activated cell sorting multicolor staining and immunohistochemistry. A strong accumulation of Tregs was observed on days 14 and 30 in the ischemic hemisphere accompanied by the elevated presence and activation of microglia. Dendritic cells and macrophages were found on each analyzed day. About 60% of Foxp3(+) Tregs in ischemic hemispheres were positive for the proliferation marker Ki-67 on days 7 and 14 after MCAO. The transfer of naive CD4(+) cells depleted of Foxp3(+) Tregs into RAG1(-/-) mice 1 day before MCAO did not lead to a de novo generation of Tregs 14 days after surgery. After depletion of CD25(+) Tregs, no changes regarding neurologic outcome were detected. The sustained presence of Tregs in the brain after MCAO indicates a long-lasting immunological alteration and involvement of brain cells in immunoregulatory mechanisms.

Prostaglandin E2 and SOCS1 have a role in intestinal immune tolerance

PubMed Central

Chinen, Takatoshi; Komai, Kyoko; Muto, Go; Morita, Rimpei; Inoue, Naoko; Yoshida, Hideyuki; Sekiya, Takashi; Yoshida, Ryoko; Nakamura, Kazuhiko; Takayanagi, Ryoichi; Yoshimura, Akihiko

2011-01-01

Interleukin 10 (IL-10) and regulatory T cells (Tregs) maintain tolerance to intestinal microorganisms. However, Il10−/−Rag2−/− mice, which lack IL-10 and Tregs, remain healthy, suggesting the existence of other mechanisms of tolerance. Here, we identify suppressor of cytokine signalling 1 (SOCS1) as an essential mediator of immune tolerance in the intestine. Socs1−/−Rag2−/− mice develop severe colitis, which can be prevented by the reduction of microbiota and the transfer of IL-10-sufficient Tregs. Additionally, we find an essential role for prostaglandin E2 (PGE2) in the maintenance of tolerance within the intestine in the absence of Tregs. Socs1−/− dendritic cells are resistant to PGE2-mediated immunosuppression because of dysregulated cytokine signalling. Thus, we propose that SOCS1 and PGE2, potentially interacting together, act as an alternative intestinal tolerance mechanism distinct from IL-10 and Tregs. PMID:21304519

Systemic Inflammatory Response Elicited by Superantigen Destabilizes T Regulatory Cells Rendering them Ineffective during Toxic Shock Syndrome 1

PubMed Central

Tilahun, Ashenafi Y.; Chowdhary, Vaidehi R.; David, Chella S.; Rajagopalan, Govindarajan

2014-01-01

Life-threatening infections caused by Staphylococcus aureus, particularly the community-acquired methicillin-resistant strains of S. aureus (CA-MRSA), continue to pose serious problems. Greater virulence and increased pathogenicity of certain S. aureus strains are attributed to higher prevalence of exotoxins. Of these exotoxins, the superantigens (SAg) are likely most pathogenic because of their ability to rapidly and robustly activate the T cells even in extremely small quantities. Therefore, countering SAg-mediated T cell activation using T regulatory cells (Tregs) might be beneficial in diseases such as toxic shock syndrome (TSS). As the normal numbers of endogenous Tregs in a typical host are insufficient, we hypothesized that increasing the Treg numbers by administration of IL2-anti-IL2 antibody complexes (IL2C) or by adoptive transfer of ex vivo expanded Tregs might be more effective in countering SAg-mediated immune activation. HLA-DR3 transgenic mice that closely recapitulate human TSS, were treated with IL2C to increase endogenous Tregs or received ex vivo expanded Tregs. Subsequently, they were challenged with SAg to induce TSS. Analyses of various parameters reflective of TSS (serum cytokine/chemokine levels, multiple organ pathology and SAg-induced peripheral T cell expansion) indicated that increasing the Tregs failed to mitigate TSS. On the contrary, serum IFN-γ levels were increased in IL2C treated mice. Exploration into the reasons behind the lack of protective effect of Tregs revealed IL-17 and IFN-γ-dependent loss of Tregs during TSS. In addition, significant upregulation of GITR on conventional T cells during TSS could render them resistant to Treg mediated suppression, contributing to failure of Treg-mediated immune regulation. PMID:25092888

Regulatory T cells in multiple sclerosis and myasthenia gravis.

PubMed

Danikowski, K M; Jayaraman, S; Prabhakar, B S

2017-06-09

Multiple sclerosis (MS) is a chronic debilitating disease of the central nervous system primarily mediated by T lymphocytes with specificity to neuronal antigens in genetically susceptible individuals. On the other hand, myasthenia gravis (MG) primarily involves destruction of the neuromuscular junction by antibodies specific to the acetylcholine receptor. Both autoimmune diseases are thought to result from loss of self-tolerance, which allows for the development and function of autoreactive lymphocytes. Although the mechanisms underlying compromised self-tolerance in these and other autoimmune diseases have not been fully elucidated, one possibility is numerical, functional, and/or migratory deficits in T regulatory cells (Tregs). Tregs are thought to play a critical role in the maintenance of peripheral immune tolerance. It is believed that Tregs function by suppressing the effector CD4+ T cell subsets that mediate autoimmune responses. Dysregulation of suppressive and migratory markers on Tregs have been linked to the pathogenesis of both MS and MG. For example, genetic abnormalities have been found in Treg suppressive markers CTLA-4 and CD25, while others have shown a decreased expression of FoxP3 and IL-10. Furthermore, elevated levels of pro-inflammatory cytokines such as IL-6, IL-17, and IFN-γ secreted by T effectors have been noted in MS and MG patients. This review provides several strategies of treatment which have been shown to be effective or are proposed as potential therapies to restore the function of various Treg subsets including Tr1, iTr35, nTregs, and iTregs. Strategies focusing on enhancing the Treg function find importance in cytokines TGF-β, IDO, interleukins 10, 27, and 35, and ligands Jagged-1 and OX40L. Likewise, strategies which affect Treg migration involve chemokines CCL17 and CXCL11. In pre-clinical animal models of experimental autoimmune encephalomyelitis (EAE) and experimental autoimmune myasthenia gravis (EAMG), several strategies have been shown to ameliorate the disease and thus appear promising for treating patients with MS or MG.

Regulatory T Cell Responses to High-Dose Methylprednisolone in Active Systemic Lupus Erythematosus.

PubMed

Mathian, Alexis; Jouenne, Romain; Chader, Driss; Cohen-Aubart, Fleur; Haroche, Julien; Fadlallah, Jehane; Claër, Laetitia; Musset, Lucile; Gorochov, Guy; Amoura, Zahir; Miyara, Makoto

2015-01-01

A slight increase in the proportion of circulating regulatory T (Treg) cells has been reported in systemic lupus erythematosus (SLE) patients taking oral prednisone. The effects of intravenous (IV) high dose methylprednisolone (MP) on Tregs have not yet been described, especially in active SLE. We prospectively analyzed the proportion of circulating CD4+ Treg cell subsets defined as follows: (1) naïve Treg (nTreg) FoxP3lowCD45RA+ cells; (2) effector Treg (eTreg) FoxP3highCD45RA- cells; and (3) non-suppressive FoxP3lowCD45RA- cells (non-regulatory Foxp3low T cells). Peripheral blood mononuclear cells of patients with active SLE were analyzed before the first infusion of IV high dose MP (day 0) and the following days (day 1, day 2, ±day 3 and ±day 8). The activity of SLE was assessed by the SLEDAI score. Seventeen patients were included. Following MP infusions, the median (range) percentage of eTregs significantly increased from 1.62% (0.53-8.43) at day 0 to 2.80% (0.83-14.60) at day 1 (p = 0.003 versus day 0), 4.64% (0.50-12.40) at day 2 (p = 0.06 versus day 1) and 7.50% (1.02-20.70) at day 3 (p = 0.008 versus day 2), and declined to baseline values at day 8. Expanding eTreg cells were actively proliferating, as they expressed Ki-67. The frequency of non-regulatory FoxP3low T cells decreased from 6.39% (3.20-17.70) at day 0 to 4.74% (1.03-9.72) at day 2 (p = 0.005); nTreg frequency did not change. All patients clinically improved immediately after MP pulses. The absence of flare after one year of follow up was associated with a higher frequency of eTregs at day 2. IV high dose MP induces a rapid, dramatic and transient increase in circulating regulatory T cells. This increase may participate in the preventive effect of MP on subsequent flares in SLE.

Regulatory T Cell Responses to High-Dose Methylprednisolone in Active Systemic Lupus Erythematosus

PubMed Central

Chader, Driss; Cohen-Aubart, Fleur; Haroche, Julien; Fadlallah, Jehane; Claër, Laetitia; Musset, Lucile; Gorochov, Guy; Amoura, Zahir; Miyara, Makoto

2015-01-01

Background/Purpose A slight increase in the proportion of circulating regulatory T (Treg) cells has been reported in systemic lupus erythematosus (SLE) patients taking oral prednisone. The effects of intravenous (IV) high dose methylprednisolone (MP) on Tregs have not yet been described, especially in active SLE. Methods We prospectively analyzed the proportion of circulating CD4+ Treg cell subsets defined as follows: (1) naïve Treg (nTreg) FoxP3lowCD45RA+ cells; (2) effector Treg (eTreg) FoxP3highCD45RA− cells; and (3) non-suppressive FoxP3lowCD45RA− cells (non-regulatory Foxp3low T cells). Peripheral blood mononuclear cells of patients with active SLE were analyzed before the first infusion of IV high dose MP (day 0) and the following days (day 1, day 2, ±day 3 and ±day 8). The activity of SLE was assessed by the SLEDAI score. Results Seventeen patients were included. Following MP infusions, the median (range) percentage of eTregs significantly increased from 1.62% (0.53–8.43) at day 0 to 2.80% (0.83–14.60) at day 1 (p = 0.003 versus day 0), 4.64% (0.50–12.40) at day 2 (p = 0.06 versus day 1) and 7.50% (1.02–20.70) at day 3 (p = 0.008 versus day 2), and declined to baseline values at day 8. Expanding eTreg cells were actively proliferating, as they expressed Ki-67. The frequency of non-regulatory FoxP3low T cells decreased from 6.39% (3.20–17.70) at day 0 to 4.74% (1.03–9.72) at day 2 (p = 0.005); nTreg frequency did not change. All patients clinically improved immediately after MP pulses. The absence of flare after one year of follow up was associated with a higher frequency of eTregs at day 2. Conclusion IV high dose MP induces a rapid, dramatic and transient increase in circulating regulatory T cells. This increase may participate in the preventive effect of MP on subsequent flares in SLE. PMID:26629828

Umbilical cord-derived mesenchymal stem cells reversed the suppressive deficiency of T regulatory cells from peripheral blood of patients with multiple sclerosis in a co-culture – a preliminary study

PubMed Central

Yang, Hongna; Sun, Jinhua; Wang, Feng; Li, Yan; Bi, Jianzhong; Qu, Tingyu

2016-01-01

The immunoregulatory function of T regulatory cells (Tregs) is impaired in multiple sclerosis (MS). Recent studies have shown that umbilical cord-derived mesenchymal stem cells (UC-MSCs) exert regulatory effect on the functions of immune cells. Thus, we investigated whether UC-MSCs could improve the impaired function of Tregs from MS patients. Co-cultures of UC-MSCs with PBMCs of MS patients were performed for 3 days. Flow cytometry was used to determine the frequency of Tregs. A cell proliferation assay was used to evaluate the suppressive capacity of Tregs. ELISA was conducted for cytokine analysis in the co-cultures. Our results showed that UC-MSCs significantly increased the frequency of CD4+CD25+CD127low/− Tregs in resting CD4+ T cells (p<0.01) from MS, accompanied by the significantly augmented production of cytokine prostaglandin E2, transforming growth factor (−β1, and interleukin-10, along with a reduced interferon-γ production in these co-cultures (p<0.05 - 0.01). More importantly, UC-MSC-primed Tregs of MS patients significantly inhibited the proliferation of PHA-stimulated autologous and allogeneic CD4+CD25− T effector cells (Teffs) from MS patients and healthy individuals compared to non-UC-MSC-primed (naïve) Tregs from the same MS patients (p<0.01). Furthermore, no remarkable differences in suppressing the proliferation of PHA-stimulated CD4+CD25− Teffs was observed in UC-MSC-primed Tregs from MS patients and naïve Tregs from healthy subjects. The impaired suppressive function of Tregs from MS can be completely reversed in a co-culture by UC-MSC modulation. This report is the first to demonstrate that functional defects of Tregs in MS can be repaired in vitro using a simple UC-MSC priming approach. PMID:27705922

Regulatory T-Cells in Chronic Lymphocytic Leukemia and Autoimmune Diseases

PubMed Central

D’Arena, Giovanni; Rossi, Giovanni; Vannata, Barbara; Deaglio, Silvia; Mansueto, Giovanna; D’Auria, Fiorella; Statuto, Teodora; Simeon, Vittorio; De Martino, Laura; Marandino, Aurelio; Del Poeta8, Giovanni; De Feo, Vincenzo; Musto, Pellegrino

2012-01-01

Regulatory T-cells (Tregs) constitute a small subset of cells that are actively involved in maintaining self-tolerance, in immune homeostasis and in antitumor immunity. They are thought to play a significant role in the progression of cancer and are generally increased in patient with chronic lymphocytic leukemia (CLL). Their number correlates with more aggressive disease status and is predictive of the time to treatment, as well. Moreover, it is now clear that dysregulation in Tregs cell frequency and/or function may result in a plethora of autoimmune diseases, including multiple sclerosis, type 1 diabetes mellitus, myasthenia gravis, systemic lupus erythematosus, autoimmune lymphoproliferative disorders, rheumatoid arthritis, and psoriasis. Efforts are made aiming to develop approaches to deplete Tregs or inhibit their function in cancer and autoimmune disorders, as well. PMID:22973497

Hydrogen Treatment Protects Mice Against Chronic Pancreatitis by Restoring Regulatory T Cells Loss.

PubMed

Chen, Luguang; Ma, Chao; Bian, Yun; Li, Jing; Wang, Tiegong; Su, Li; Lu, Jianping

2017-01-01

Chronic pancreatitis is an inflammatory disease of the pancreas characterized by progressive tissue destruction and fibrogenesis. The development of chronic pancreatitis is associated with immune cell dysregulation. Currently, the specific and effective treatment of chronic pancreatitis remains absent. By using an L-arginine induced chronic pancreatitis mouse model, we tested the therapeutic potential of hydrogen, a strong hydroxyl radicals scavenger, in the chronic pancreatitis model. Tissue inflammation, damage and fibrosis were analyzed on HE, TUNEL, MPO, and sirius staining. Pancreas levels of MDA content, SOD activity, TNF-α , IL-10 cytokine expression and serum amylase and lipase activity were determined by ELISA and absorbance assay. Apoptosis, T cells subtype proportion and intracellular level of reactive oxygen species (ROS) were analyzed by flow cytometry. Tregs adoptive transfer and CD25 neutralization were used to validate the role of Tregs in chronic pancreatitis. We found that hydrogen treatment significantly improved multiple symptoms of chronic pancreatitis. The number of Tregs was reduced in chronic pancreatitis mice, while hydrogen treatment restored the Treg loss by L-arginine administrations. Depletion of Tregs abolished the protective effect of hydrogen treatment in chronic pancreatitis. In vitro study showed that hydrogen blocked ROS generation in Tregs and promoted Tregs survival. Hydrogen treatment showed reliable benefits in controlling the severity of chronic pancreatitis. Our study supported that hydrogen could be used as a novel treatment in chronic pancreatitis patient in the future. © 2017 The Author(s). Published by S. Karger AG, Basel.

Regulatory T Cells in Skin Facilitate Epithelial Stem Cell Differentiation.

PubMed

Ali, Niwa; Zirak, Bahar; Rodriguez, Robert Sanchez; Pauli, Mariela L; Truong, Hong-An; Lai, Kevin; Ahn, Richard; Corbin, Kaitlin; Lowe, Margaret M; Scharschmidt, Tiffany C; Taravati, Keyon; Tan, Madeleine R; Ricardo-Gonzalez, Roberto R; Nosbaum, Audrey; Bertolini, Marta; Liao, Wilson; Nestle, Frank O; Paus, Ralf; Cotsarelis, George; Abbas, Abul K; Rosenblum, Michael D

2017-06-01

The maintenance of tissue homeostasis is critically dependent on the function of tissue-resident immune cells and the differentiation capacity of tissue-resident stem cells (SCs). How immune cells influence the function of SCs is largely unknown. Regulatory T cells (Tregs) in skin preferentially localize to hair follicles (HFs), which house a major subset of skin SCs (HFSCs). Here, we mechanistically dissect the role of Tregs in HF and HFSC biology. Lineage-specific cell depletion revealed that Tregs promote HF regeneration by augmenting HFSC proliferation and differentiation. Transcriptional and phenotypic profiling of T regs and HFSCs revealed that skin-resident Tregs preferentially express high levels of the Notch ligand family member, Jagged 1 (Jag1). Expression of Jag1 on Tregs facilitated HFSC function and efficient HF regeneration. Taken together, our work demonstrates that Tregs in skin play a major role in HF biology by promoting the function of HFSCs. Copyright © 2017 Elsevier Inc. All rights reserved.

Immune dysregulation in patients with PTEN hamartoma tumor syndrome: Analysis of FOXP3 regulatory T cells.

PubMed

Chen, Hannah H; Händel, Norman; Ngeow, Joanne; Muller, James; Hühn, Michael; Yang, Huei-Ting; Heindl, Mario; Berbers, Roos-Marijn; Hegazy, Ahmed N; Kionke, Janina; Yehia, Lamis; Sack, Ulrich; Bläser, Frank; Rensing-Ehl, Anne; Reifenberger, Julia; Keith, Julia; Travis, Simon; Merkenschlager, Andreas; Kiess, Wieland; Wittekind, Christian; Walker, Lisa; Ehl, Stephan; Aretz, Stefan; Dustin, Michael L; Eng, Charis; Powrie, Fiona; Uhlig, Holm H

2017-02-01

Patients with heterozygous germline mutations in phosphatase and tensin homolog deleted on chromosome 10 (PTEN) experience autoimmunity and lymphoid hyperplasia. Because regulation of the phosphoinositide 3-kinase (PI3K) pathway is critical for maintaining regulatory T (Treg) cell functions, we investigate Treg cells in patients with heterozygous germline PTEN mutations (PTEN hamartoma tumor syndrome [PHTS]). Patients with PHTS were assessed for immunologic conditions, lymphocyte subsets, forkhead box P3 (FOXP3) + Treg cell levels, and phenotype. To determine the functional importance of phosphatases that control the PI3K pathway, we assessed Treg cell induction in vitro, mitochondrial depolarization, and recruitment of PTEN to the immunologic synapse. Autoimmunity and peripheral lymphoid hyperplasia were found in 43% of 79 patients with PHTS. Immune dysregulation in patients with PHTS included lymphopenia, CD4 + T-cell reduction, and changes in T- and B-cell subsets. Although total CD4 + FOXP3 + Treg cell numbers are reduced, frequencies are maintained in the blood and intestine. Despite pathogenic PTEN mutations, the FOXP3 + T cells are phenotypically normal. We show that the phosphatase PH domain leucine-rich repeat protein phosphatase (PHLPP) downstream of PTEN is highly expressed in normal human Treg cells and provides complementary phosphatase activity. PHLPP is indispensable for the differentiation of induced Treg cells in vitro and Treg cell mitochondrial fitness. PTEN and PHLPP form a phosphatase network that is polarized at the immunologic synapse. Heterozygous loss of function of PTEN in human subjects has a significant effect on T- and B-cell immunity. Assembly of the PTEN-PHLPP phosphatase network allows coordinated phosphatase activities at the site of T-cell receptor activation, which is important for limiting PI3K hyperactivation in Treg cells despite PTEN haploinsufficiency. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

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

PubMed

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.

Increased regulatory T-cell numbers are associated with farm milk exposure and lower atopic sensitization and asthma in childhood.

PubMed

Lluis, Anna; Depner, Martin; Gaugler, Beatrice; Saas, Philippe; Casaca, Vera Isabel; Raedler, Diana; Michel, Sven; Tost, Jorg; Liu, Jing; Genuneit, Jon; Pfefferle, Petra; Roponen, Marjut; Weber, Juliane; Braun-Fahrländer, Charlotte; Riedler, Josef; Lauener, Roger; Vuitton, Dominique Angèle; Dalphin, Jean-Charles; Pekkanen, Juha; von Mutius, Erika; Schaub, Bianca

2014-02-01

European cross-sectional studies have suggested that prenatal and postnatal farm exposure decreases the risk of allergic diseases in childhood. Underlying immunologic mechanisms are still not understood but might be modulated by immune-regulatory cells early in life, such as regulatory T (Treg) cells. We sought to assess whether Treg cells from 4.5-year-old children from the Protection against Allergy: Study in Rural Environments birth cohort study are critical in the atopy and asthma-protective effect of farm exposure and which specific exposures might be relevant. From 1133 children, 298 children were included in this study (149 farm and 149 reference children). Detailed questionnaires until 4 years of age assessed farming exposures over time. Treg cells were characterized as upper 20% CD4(+)CD25(+) forkhead box protein 3 (FOXP3)(+) (intracellular) in PBMCs before and after stimulation (with phorbol 12-myristate 13-acetate/ionomycin or LPS), and FOXP3 demethylation was assessed. Atopic sensitization was defined by specific IgE measurements; asthma was defined by a doctor's diagnosis. Treg cells were significantly increased in farm-exposed children after phorbol 12-myristate 13-acetate/ionomycin and LPS stimulation. Exposure to farm milk was defined as a relevant independent farm-related exposure supported by higher FOXP3 demethylation. Treg cell (upper 20% CD4(+)CD25(+), FOXP3(+) T cells) numbers were significantly negatively associated with doctor-diagnosed asthma (LPS stimulated: adjusted odds ratio, 0.26; 95% CI, 0.08-0.88) and perennial IgE (unstimulated: adjusted odds ratio, 0.21; 95% CI, 0.08-0.59). Protection against asthma by farm milk exposure was partially mediated by Treg cells. Farm milk exposure was associated with increased Treg cell numbers on stimulation in 4.5-year-old children and might induce a regulatory phenotype early in life, potentially contributing to a protective effect for the development of childhood allergic diseases. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

End-stage renal disease, dialysis, kidney transplantation and their impact on CD4+ -T-cell differentiation.

PubMed

Schaier, Matthias; Leick, Angele; Uhlmann, Lorenz; Kälble, Florian; Morath, Christian; Eckstein, Volker; Ho, Anthony; Mueller-Tidow, Carsten; Meuer, Stefan; Mahnke, Karsten; Sommerer, Claudia; Zeier, Martin; Steinborn, Andrea

2018-05-02

Premature aging of both CD4 + -regulatory- (Tregs) and CD4 + -responder-T-cells (Tresps) in end-stage renal disease (ESRD) patients is expected to affect the success of later kidney transplantation. Both T-cell populations are released from the thymus as inducible co-stimulatory (ICOS + -) and ICOS - -recent thymic emigrant (RTE)-Tregs/Tresps, which differ primarily in their proliferative capacities. In this study, we analysed the effect of ESRD and subsequent renal replacement therapies on the differentiation of ICOS + - and ICOS - -RTE-Tregs/Tresps into ICOS + - or ICOS - -CD31 - -Memory-Tregs/Tresps and examined whether diverging pathways affected the suppressive activity of ICOS + - and ICOS - -Tregs in co-culture with autologous Tresps. Compared to healthy controls, we found an increased differentiation of ICOS + -RTE-Tregs/Tresps and ICOS - -RTE-Tregs via CD31 + -memory-Tregs/Tresps into CD31 - -memory-Tregs/Tresps in ESRD and dialysis patients. In contrast, ICOS - -RTE-Tresps showed an increased differentiation via ICOS - -mature naïve (MN)-Tresps into CD31 - -memory-Tresps. Thereby, the ratio of ICOS + -Tregs/ICOS + -Tresps was not changed, while that of ICOS - -Tregs/ICOS - -Tresps was significantly increased. This differentiation preserved the suppressive activity of both Treg populations in ESRD and partly in dialysis patients. After transplantation, the increased differentiation of ICOS + - and ICOS - -RTE-Tresps proceeded, while that of ICOS + -RTE-Tregs ceased and that of ICOS - -RTE-Tregs switched to an increased differentiation via ICOS - -MN-Tregs. Consequently, the ratios of ICOS + -Tregs/ICOS + -Tresps and of ICOS - -Tregs/ICOS - -Tresps decreased significantly, reducing the suppressive activity of Tregs markedly. Our data reveal that an increased tolerance-inducing differentiation of ICOS + - and ICOS - -Tregs preserves the functional activity of Tregs in ESRD patients, but this cannot be maintained during long-term renal replacement therapy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Cutting Edge: c-Maf Is Required for Regulatory T Cells To Adopt RORγt+ and Follicular Phenotypes.

PubMed

Wheaton, Joshua D; Yeh, Chen-Hao; Ciofani, Maria

2017-12-15

Regulatory T cells (Tregs) adopt specialized phenotypes defined by coexpression of lineage-defining transcription factors, such as RORγt, Bcl-6, or PPARγ, alongside Foxp3. These Treg subsets have unique tissue distributions and diverse roles in maintaining organismal homeostasis. However, despite extensive functional characterization, the factors driving Treg specialization are largely unknown. In this article, we show that c-Maf is a critical transcription factor regulating this process in mice, essential for generation of both RORγt + Tregs and T follicular regulatory cells, but not for adipose-resident Tregs. c-Maf appears to function primarily in Treg specialization, because IL-10 production, expression of other effector molecules, and general immune homeostasis are not c-Maf dependent. As in other T cells, c-Maf is induced in Tregs by IL-6 and TGF-β, suggesting that a combination of inflammatory and tolerogenic signals promote c-Maf expression. Therefore, c-Maf is a novel regulator of Treg specialization, which may integrate disparate signals to facilitate environmental adaptation. Copyright © 2017 by The American Association of Immunologists, Inc.

Percentage and function of CD4+CD25+ regulatory T cells in patients with hyperthyroidism

PubMed Central

Jiang, Ting-Jun; Cao, Xue-Liang; Luan, Sha; Cui, Wan-Hui; Qiu, Si-Huang; Wang, Yi-Chao; Zhao, Chang-Jiu; Fu, Peng

2018-01-01

The current study observed the percentage of peripheral blood (PB) CD4+CD25+ regulatory T cells (Tregs) and the influence of CD4+CD25+ Tregs on the proliferation of naïve CD4 T cells in patients with hyperthyroidism. Furthermore, preliminary discussions are presented on the action mechanism of CD4+CD25+ Tregs on hyperthyroidism attacks. The present study identified that compared with the percentage of PB CD4+CD25+ Tregs in healthy control subjects, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism (P>0.05). For patients with hyperthyroidism, CD4+CD25+ Tregs exhibited significantly reduced inhibition of the proliferation of naïve CD4 T cells and decreased secretion capacity on the cytokines of CD4 T cells, compared with those of healthy control subjects (P<0.05). In addition, it was demonstrated that thyroid function of patients with hyperthyroidism was significantly improved (P<0.05) subsequent to receiving medication. Compared with the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism before treatment, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in hyperthyroidism patients following treatment (P>0.05). In the patients with hyperthyroidism, following treatment, CD4+CD25+ Tregs exhibited significantly increased inhibition of the proliferation of naïve CD4 T cells and increased secretion capacity of CD4 T cell cytokines, compared with those of the patients with hyperthyroidism prior to treatment (P<0.05). PB CD4+CD25+ Tregs function was decreased in patients with hyperthyroidism, and its non-proportional decrease may be closely associated with the occurrence and progression of hyperthyroidism. PMID:29207121

Leptin Directly Promotes T Cell Glycolytic Metabolism to Drive Effector T cell Differentiation in Autoimmunity

PubMed Central

Gerriets, Valerie A.; Danzaki, Keiko; Kishton, Rigel J.; Eisner, William; Nichols, Amanda G.; Saucillo, Donte C.; Shinohara, Mari L.; MacIver, Nancie J.

2016-01-01

Upon activation, T cells require energy for growth, proliferation and function. Effector T cells (Teff), such as Th1 and Th17, utilize high levels of glucose uptake and glycolysis to fuel proliferation and function. In contrast, Treg instead require oxidative metabolism to fuel suppressive function. It remains unknown how Teff/Treg metabolism is altered in settings of malnutrition, when nutrients are limited and circulating leptin levels are low. We therefore examined the role of malnutrition and associated hypoleptinemia on Teff versus Treg. We found that both malnutrition-associated hypoleptinemia and T cell-specific leptin receptor knockout suppressed Teff number, function, and glucose metabolism, but did not alter Treg metabolism or suppressive function. Using the autoimmune model EAE, we confirmed that fasting-induced hypoleptinemia altered Teff, but not Treg, glucose metabolism and function in vivo, leading to decreased disease severity. To explore potential mechanisms, we examined HIF-1α, a key regulator of Th17 differentiation and Teff glucose metabolism, and found HIF-1α expression was decreased in T cell-specific leptin receptor knockout Th17 cells, and in Teff cells from fasted EAE mice, but was unchanged in Treg. Altogether, these data demonstrate a selective, cell-intrinsic requirement for leptin to upregulate glucose metabolism and maintain function in Teff, but not Treg. PMID:27222115

Regulatory T cells with reduced repressor capacities are extensively amplified in pulmonary sarcoid lesions and sustain granuloma formation.

PubMed

Rappl, Gunter; Pabst, Stefan; Riemann, Dagmar; Schmidt, Annette; Wickenhauser, Claudia; Schütte, Wolfgang; Hombach, Andreas A; Seliger, Barbara; Grohé, Christian; Abken, Hinrich

2011-07-01

Sarcoidosis can evolve into a chronic disease with persistent granulomas accompanied by progressive fibrosis. While an unlimited inflammatory response suggests an impaired immune control in sarcoid lesions, it stands in contrast to the massive infiltration with CD4(+)CD25(high)FoxP3(+) regulatory T cells. We here revealed that those Treg cells in affected lung lesions were mainly derived from activated natural Treg cells with GARP (LRRC32)-positive phenotype but exhibited reduced repressor capacities despite high IL-10 and TGF-beta 1 levels. The repressive capacity of blood Treg cells, in contrast, was not impaired compared to age-matched healthy donors. Treg derived cells in granuloma lesions have undergone extensive rounds of amplifications indicated by shortened telomeres compared to blood Treg cells of the same patient. Lesional Treg derived cells moreover secreted pro-inflammatory cytokines including IL-4 which sustains granuloma formation through fibroblast amplification and the activation of mast cells, the latter indicated by the expression of membrane-bound oncostatin M. Copyright © 2011 Elsevier Inc. All rights reserved.

Mammalian Sterile 20-like Kinase 1 (Mst1) Enhances the Stability of Forkhead Box P3 (Foxp3) and the Function of Regulatory T Cells by Modulating Foxp3 Acetylation.

PubMed

Li, Jiang; Du, Xingrong; Shi, Hao; Deng, Kejing; Chi, Hongbo; Tao, Wufan

2015-12-25

Regulatory T cells (Tregs) play crucial roles in maintaining immune tolerance. The transcription factor Foxp3 is a critical regulator of Treg development and function, and its expression is regulated at both transcriptional and post-translational levels. Acetylation by lysine acetyl transferases/lysine deacetylases is one of the main post-translational modifications of Foxp3, which regulate Foxp3's stability and transcriptional activity. However, the mechanism(s) by which the activities of these lysine acetyl transferases/lysine deacetylases are regulated to preserve proper Foxp3 acetylation during Treg development and maintenance of Treg function remains to be determined. Here we report that Mst1 can enhance Foxp3 stability, its transcriptional activity, and Treg function by modulating the Foxp3 protein at the post-translational level. We discovered that Mst1 could increase the acetylation of Foxp3 by inhibiting Sirt1 activity, which requires the Mst1 kinase activity. We also found that Mst1 could attenuate Sirt1-mediated deacetylation of Foxp3 through directly interacting with Foxp3 to prevent or interfere the interaction between Sirt1 and Foxp3. Therefore, Mst1 can regulate Foxp3 stability in kinase-dependent and kinase-independent manners. Finally, we showed that treatment of Mst1(-/-) Tregs with Ex-527, a Sirt1-specific inhibitor, partially restored the suppressive function of Mst1(-/-) Tregs. Our studies reveal a novel mechanism by which Mst1 enhances Foxp3 expression and Treg function at the post-translational level. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

The possible role of CD4⁺CD25(high)Foxp3⁺/CD4⁺IL-17A⁺ cell imbalance in the autoimmunity of patients with Hashimoto thyroiditis.

PubMed

Xue, Haibo; Yu, Xiurong; Ma, Lei; Song, Shoujun; Li, Yuanbin; Zhang, Li; Yang, Tingting; Liu, Huan

2015-12-01

Hashimoto thyroiditis (HT) is a prototypic organ-specific autoimmune thyroid disease, for which the exact etiology remains unclear. The aim of this study was to investigate dynamic changes in regulatory T cell (Treg) and T helper 17 cell (Th17) populations in patients with HT at different stages of thyroid dysfunction, as well as to analyze the possible correlation between the Treg/Th17 cell axis and autoimmune status in HT. We assessed thyroid function and autoantibody serology both in HT patients and in healthy controls (HCs) and divided HT patients into three subgroups according to thyroid function. We then determined the percentages of Treg and Th17 cells in peripheral blood mononuclear cells and analyzed mRNA expression of the Treg and Th17 cell-defining transcription factors Foxp3 and RORγt. In addition, serum levels of TGF-β and IL-17A were assessed. We found that the percentage of Treg cells, Foxp3 mRNA levels, and the ratio of Treg/Th17 cells were all significantly lower in HT patients, while Th17 cell percentages and RORγt mRNA levels were significantly higher. Interestingly, we also observed significant differences in these measurements between HT patient subgroups. Serum IL-17A levels were markedly increased in HT patients, while serum concentrations of TGF-β were lower, compared to HCs. The ratio of Treg/Th17 cells was negatively correlated with the levels of serum thyroperoxidase antibody, thyroglobulin antibody, and thyrotropin (TSH) in HT patients. Taken together, our data suggest that the balance between Treg and Th17 cells shifts in favor of Th17 cells during clinical progression of HT, which is negatively correlated with levels of thyroid-specific autoantibodies and TSH, implying that Treg/Th17 cell imbalance may contribute to thyroid damage in HT.

Tolerogenic Dendritic Cells Generated with Tofacitinib Ameliorate Experimental Autoimmune Encephalomyelitis through Modulation of Th17/Treg Balance

PubMed Central

Luo, Shasha; Zou, Qiang

2016-01-01

It is well known that dendritic cells (DCs) play a pivotal role in triggering self-specific responses. Conversely, tolerogenic DCs (tolDCs), a specialized subset, induce tolerance and negatively regulate autoreactive responses. Tofacitinib, a Janus kinase inhibitor developed by Pfizer for treatment of rheumatoid arthritis, is probable to be a promising candidate for inducing tolDCs. The aims of this study were to evaluate the effectiveness of tolDCs induced by tofacitinib in a myelin oligodendrocyte glycoprotein- (MOG-) specific experimental autoimmune encephalomyelitis (EAE) model and to investigate their effects on Th17/Treg balance in the animal model of multiple sclerosis (MS). Our results revealed that tofacitinib-treated DCs maintained a steady semimature phenotype with a low level of proinflammatory cytokines and costimulatory molecules. DCs treated by tofacitinib also induced antigen-specific T cells hyporesponsiveness in a concentration-dependent manner. Upon intravenous injection into EAE mice, MOG pulsed tolDCs significantly dampened disease activity, and adoptive cell therapy (ACT) disturbed Th17/Treg balance with a remarkable decrease of Th1/Th17 cells and an increase in regulatory T cells (Tregs). Overall, DCs modified by tofacitinib exhibited a typical tolerogenic phenotype, and the antigen-specific tolDCs may represent a new avenue of research for the development of future clinical treatments for MS. PMID:28070525

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

PubMed

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.

Early Pregnancy Factor Enhances the Generation and Function of CD4+CD25+ Regulatory T Cells.

PubMed

Chen, Quangang; Zhu, Xiaorong; Chen, Renjin; Liu, Jing; Liu, Peng; Hu, Ankang; Wu, Lianlian; Hua, Hui; Yuan, Honghua

2016-11-01

The mechanisms of fetal semi-allograft acceptance by the mother's immune system have been the target of many immunological studies. Early pregnancy factor (EPF) is a molecule present in the serum of pregnant mammals soon after conception that has been reported to have immunomodulatory effects. In the present study, we aimed to determine whether immune cells such as CD4 + CD25 + regulatory T cells (Tregs) are involved in the suppressive mechanism of EPF. Accordingly, CD4 + CD25 - T cells were isolated from spleens of female C57BL/6 mice and stimulated with anti-CD3 antibody, anti-CD28 antibody and IL-2 in the presence or absence of EPF. Flow cytometry was used to analyze the differentiation of CD4 + CD25 - T cells to CD4 + CD25 + Tregs. We thus found a remarkable rise in the Treg ratio in the EPF-treated cells. Higher mRNA and protein levels of fork head box P3 (Foxp3), a marker of the Treg lineage, were also observed in cells treated with EPF. Furthermore, the effect of EPF on Treg immunosuppressive capacity was evaluated. EPF treatment induced the expression of interleukin-10 and transforming growth factor β1 in Tregs. The suppressive capacity of Tregs was further measured by their capability to inhibit T cell receptor-mediated proliferation of CD4 + CD25 - T cells. We thus found that EPF exposure can enhance the immunosuppressive functions of Tregs. Overall, our data suggest that EPF induces the differentiation of Tregs and increases their immunosuppressive activities, which might be an important mechanism to inhibit immune responses during pregnancy.

Evaluation of T-lymphocyte subpopulations in actinic keratosis, in situ and invasive squamous cell carcinoma of the skin.

PubMed

Stravodimou, Aristea; Tzelepi, Vassiliki; Papadaki, Helen; Mouzaki, Athanasia; Georgiou, Sophia; Melachrinou, Maria; Kourea, Eleni P

2018-05-01

Tumor infiltrating lymphocytes (TILs) represent important regulators of carcinogenesis. Cutaneous invasive squamous cell carcinoma (inSCC) develops through precursor lesions, namely in situ squamous cell carcinoma (isSCC) and actinic keratosis (AK), representing a natural model of carcinogenesis. The study evaluates TIL subpopulations in inSCC and its precursors by comparing 2 semiquantitative scoring systems, and assesses the presence of regulatory T-cells (Tregs) in these lesions. Paraffin sections from 33 cases of AK, 19 isSCCs and 34 inSCCs with adjacent precursor lesions or normal skin (NS) were immunostained for CD3, CD4, CD8 and Foxp3. TIL subgroups were evaluated by the semiquantitative Klintrup-Mäkinen (K-M) score, and by a more detailed modification of this system. Treg counts were assessed by image analysis quantification. An increase of all TIL subpolulations from precursor lesions toward inSCC was shown by both scoring systems. Treg counts progressively increased from NS to AK and isSCC, but decreased in inSCC. Tregs were more numerous in pT2 and around indolent inSCCs compared to T1 and aggressive subtypes. T-cells and cytotoxic T-cells progressively increase in cutaneous squamous cell carcinogenesis, while Treg counts diminish in inSCC. The K-M score is an appropriate, easily applicable TIL scoring system in cutaneous inSCC. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

An essential role for IL-2 receptor in regulatory T cell function

PubMed Central

Levine, Andrew G; Fan, Xiying; Klein, Ulf; Zheng, Ye; Gasteiger, Georg; Feng, Yongqiang; Fontenot, Jason D.; Rudensky, Alexander Y.

2016-01-01

Regulatory T (Treg) cells, expressing abundant amounts of the IL-2 receptor (IL-2R), are reliant on IL-2 produced by activated T cells. This feature implied a key role for a simple network based on IL-2 consumption by Treg cells in their suppressor function. However, congenital deficiency in IL-2R results in reduced expression of the Treg cell lineage specification factor Foxp3, confounding experimental efforts to understand the role of IL-2R expression and signaling in Treg suppressor function. Using genetic gain and loss of function approaches, we demonstrate that IL-2 capture is dispensable for control of CD4+ T cells, but is important for limiting CD8+ T cell activation, and that IL-2R dependent STAT5 transcription factor activation plays an essential role in Treg cell suppressor function separable from T cell receptor signaling. PMID:27595233

Regulatory T cell effects in antitumor laser immunotherapy: a mathematical model and analysis

NASA Astrophysics Data System (ADS)

Dawkins, Bryan A.; Laverty, Sean M.

2016-03-01

Regulatory T cells (Tregs) have tremendous influence on treatment outcomes in patients receiving immunotherapy for cancerous tumors. We present a mathematical model incorporating the primary cellular and molecular components of antitumor laser immunotherapy. We explicitly model developmental classes of dendritic cells (DCs), cytotoxic T cells (CTLs), primary and metastatic tumor cells, and tumor antigen. Regulatory T cells have been shown to kill antigen presenting cells, to influence dendritic cell maturation and migration, to kill activated killer CTLs in the tumor microenvironment, and to influence CTL proliferation. Since Tregs affect explicitly modeled cells, but we do not explicitly model dynamics of Treg themselves, we use model parameters to analyze effects of Treg immunosuppressive activity. We will outline a systematic method for assigning clinical outcomes to model simulations and use this condition to associate simulated patient treatment outcome with Treg activity.

CD4+CD62L+ Central Memory T Cells Can Be Converted to Foxp3+ T Cells

PubMed Central

Zhang, Xiaolong; Chang Li, Xian; Xiao, Xiang; Sun, Rui; Tian, Zhigang; Wei, Haiming

2013-01-01

The peripheral Foxp3+ Treg pool consists of naturally arising Treg (nTreg) and adaptive Treg cells (iTreg). It is well known that naive CD4+ T cells can be readily converted to Foxp3+ iTreg in vitro, and memory CD4+ T cells are resistant to conversion. In this study, we investigated the induction of Foxp3+ T cells from various CD4+ T-cell subsets in human peripheral blood. Though naive CD4+ T cells were readily converted to Foxp3+ T cells with TGF-β and IL-2 treatment in vitro, such Foxp3+ T cells did not express the memory marker CD45RO as do Foxp3+ T cells induced in the peripheral blood of Hepatitis B Virus (HBV) patients. Interestingly, a subset of human memory CD4+ T cells, defined as CD62L+ central memory T cells, could be induced by TGF-β to differentiate into Foxp3+ T cells. It is well known that Foxp3+ T cells derived from human CD4+CD25- T cells in vitro are lack suppressive functions. Our data about the suppressive functions of CD4+CD62L+ central memory T cell-derived Foxp3+ T cells support this conception, and an epigenetic analysis of these cells showed a similar methylation pattern in the FOXP3 Treg-specific demethylated region as the naive CD4+ T cell-derived Foxp3+ T cells. But further research showed that mouse CD4+ central memory T cells also could be induced to differentiate into Foxp3+ T cells, such Foxp3+ T cells could suppress the proliferation of effector T cells. Thus, our study identified CD4+CD62L+ central memory T cells as a novel potential source of iTreg. PMID:24155942

Vitamin D Status Is Positively Correlated with Regulatory T Cell Function in Patients with Multiple Sclerosis

PubMed Central

Smolders, Joost; Thewissen, Mariëlle; Peelen, Evelyn; Menheere, Paul; Cohen Tervaert, Jan Willem; Damoiseaux, Jan; Hupperts, Raymond

2009-01-01

Background In several autoimmune diseases, including multiple sclerosis (MS), a compromised regulatory T cell (Treg) function is believed to be critically involved in the disease process. In vitro, the biologically active metabolite of vitamin D has been shown to promote Treg development. A poor vitamin D status has been linked with MS incidence and MS disease activity. In the present study, we assess a potential in vivo correlation between vitamin D status and Treg function in relapsing remitting MS (RRMS) patients. Methodology/Principal Findings Serum levels of 25-hydroxyvitamin D (25(OH)D) were measured in 29 RRMS patients. The number of circulating Tregs was assessed by flow-cytometry, and their functionality was tested in vitro in a CFSE-based proliferation suppression assay. Additionally, the intracellular cytokine profile of T helper cells was determined directly ex-vivo by flow-cytometry. Serum levels of 25(OH)D correlated positively with the ability of Tregs to suppress T cell proliferation (R = 0.590, P = 0.002). No correlation between 25(OH)D levels and the number of Tregs was found. The IFN-γ/IL-4 ratio (Th1/Th2-balance) was more directed towards IL-4 in patients with favourable 25(OH)D levels (R = −0.435, P = 0.023). Conclusions/Significance These results show an association of high 25(OH)D levels with an improved Treg function, and with skewing of the Th1/Th2 balance towards Th2. These findings suggest that vitamin D is an important promoter of T cell regulation in vivo in MS patients. It is tempting to speculate that our results may not only hold for MS, but also for other autoimmune diseases. Future intervention studies will show whether modulation of vitamin D status results in modulation of the T cell response and subsequent amelioration of disease activity. PMID:19675671

Differential effects of α4β7 and GPR15 on homing of effector and regulatory T cells from patients with UC to the inflamed gut in vivo.

PubMed

Fischer, Anika; Zundler, Sebastian; Atreya, Raja; Rath, Timo; Voskens, Caroline; Hirschmann, Simon; López-Posadas, Rocío; Watson, Alastair; Becker, Christoph; Schuler, Gerold; Neufert, Clemens; Atreya, Imke; Neurath, Markus F

2016-10-01

Gut homing of lymphocytes via adhesion molecules has recently emerged as new target for therapy in IBDs. We aimed to analyse the in vivo homing of effector (Teff) and regulatory (Treg) T cells to the inflamed gut via α4β7 and G protein receptor GPR15. We assessed the expression of homing receptors on T cells in peripheral blood and inflamed mucosa. We studied the migration pattern and homing of Teff and Treg cells to the inflamed gut using intravital confocal microscopy and FACS in a humanised mouse model in dextran sodium sulfate-treated NSG (NOD.Cg-Prkdcscid-Il2rgtm1Wjl/SzJ) mice. Expression of GPR15 and α4β7 was significantly increased on Treg rather than Teff cells in peripheral blood of patients with UC as compared with Crohn's disease and controls. In vivo analysis in a humanised mouse model showed augmented gut homing of UC Treg cells as compared with controls. Moreover, suppression of UC (but not control) Teff and Treg cell homing was noted upon treatment with the α4β7 antibody vedolizumab. In contrast, siRNA blockade of GPR15 had only effects on homing of Teff cells but did not affect Treg homing in UC. Clinical vedolizumab treatment was associated with marked expansion of UC Treg cells in peripheral blood. α4β7 rather than GPR15 is crucial for increased colonic homing of UC Treg cells in vivo, while both receptors control UC Teff cell homing. Vedolizumab treatment impairs homing of UC Treg cells leading to their accumulation in peripheral blood with subsequent suppression of systemic Teff cell expansion. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Correlation of PD-1/PD-L1 Signaling Pathway with Treg/Th17 Imbalance from Asthmatic Children.

PubMed

Xi, Xia; Liu, Jing-Mei; Guo, Jun-Ying

2018-06-06

The balance between T helper 17 (Th17) and regulatory T cells (Treg) is a new paradigm in asthma pathogenesis, but no therapeutic targets could modulate the Th17/Treg balance specifically for asthma. Since previous studies have shown the programmed cell death-1(PD-1)/PD-ligand 1 (PD-L1) pathway is critical to immune homeostasis in this disease, we hypothesized that the PD-1/PD-L1 pathway might be involved in the regulation of Treg/Th17 imbalance in asthmatic children. The percentage of Treg and Th17 cells and the expression of PD-1 and PD-L1 were detected by flow cytometry in children with asthma and healthy controls. CD4+ T cells were stimulated with Th17 and Treg differentiating factors, and treated with anti-PD-1. Then cells were harvested and measured for Th17 and Treg percentages and Foxp3 and RORγt levels using RT-PCR. We observed an inverse correlation between the percentages of Treg and Th17 cells, and the expression of PD-1 and PD-L1 in the two subsets also changed in the mild persistent and moderate to severe persistent groups compared with healthy controls. In vitro, administration of anti-PD-1 could decrease Th17 percentages and RORγt mRNA, and increase Treg percentages and Foxp3 mRNA in CD4+ T cells of children with asthma in the mild persistent and moderate to persistent groups. Additionally, the role played by anti-PD-1 in regulating Treg/Th17 balance was further confirmed in an asthmatic mouse model. Alteration of the PD-1/PD-L1 pathway can modulate Treg/Th17 balance in asthmatic children. Treatment with anti-PD-1 posed protective effects on asthma models, providing a novel theoretical target for asthma. © 2018 S. Karger AG, Basel.

Viral RNA-Unprimed Rig-I Restrains Stat3 Activation in the Modulation of Regulatory T Cell/Th17 Cell Balance.

PubMed

Yang, Hui; Guo, He-Zhou; Li, Xian-Yang; Lin, Jian; Zhang, Wu; Zhao, Jun-Mei; Zhang, Hong-Xin; Chen, Sai-Juan; Chen, Zhu; Zhu, Jiang

2017-07-01

Innate immunity activation by viral RNA-primed retinoid acid inducible gene-I (Rig-I) in CD4 + T cells antagonizes TGFβ signaling to suppress the differentiation of regulatory T cells (Tregs). However, how viral RNA-unliganded Rig-I (apo-Rig-I) modulates Treg generation remains unclear. In this article, we show that, in the absence of viral infection, Treg differentiation of Rig-I -/- CD4 + T cells was compromised, in the presence of increased generation of Th17 cells and overactivation of Stat3, a critical regulator tilting the Treg/Th17 cell balance. Mechanistically, apo-Rig-I physically associates with Stat3, thereby inhibiting Jak1's association with Stat3 while facilitating Shp2's association to inhibit p-Stat3 levels. Interestingly, inhibition of Stat3 ameliorates the Treg/Th17 imbalance and the colitis observed in Rig-I -/- mice. Collectively, these results uncover an independent functional contribution of the apo-Rig-I/Stat3 interaction in the maintenance of Treg/Th17 cell balance. Copyright © 2017 by The American Association of Immunologists, Inc.

Expression of GARP selectively identifies activated human FOXP3+ regulatory T cells.

PubMed

Wang, Rui; Kozhaya, Lina; Mercer, Frances; Khaitan, Alka; Fujii, Hodaka; Unutmaz, Derya

2009-08-11

The molecules that define human regulatory T cells (Tregs) phenotypically and functionally remain to be fully characterized. We recently showed that activated human Tregs express mRNA for a transmembrane protein called glycoprotein A repetitions predominant (GARP, or LRRC32). Here, using a GARP-specific mAb, we demonstrate that expression of GARP on activated Tregs correlates with their suppressive capacity. However, GARP was not induced on T cells activated in the presence of TGFbeta, which expressed high levels of FOXP3 and lacked suppressive function. Ectopic expression of FOXP3 in conventional T cells was also insufficient for induction of GARP expression in most donors. Functionally, silencing GARP in Tregs only moderately attenuated their suppressive activity. CD25+ T cells sorted for high GARP expression displayed more potent suppressive activity compared with CD25+GARP- cells. Remarkably, CD25+GARP- T cells expanded in culture contained 3-5 fold higher IL-17-secreting cells compared with either CD25+GARP+ or CD25-GARP- cells, suggesting that high GARP expression can potentially discriminate Tregs from those that have switched to Th17 lineage. We also determined whether GARP expression correlates with FOXP3-expressing T cells in human immunodeficiency virus (HIV) -infected subjects. A subset of HIV+ individuals with high percentages of FOXP3+ T cells did not show proportionate increase in GARP+ T cells. This finding suggests that higher FOXP3 levels observed in these HIV+ individuals is possibly due to immune activation rather than to an increase in Tregs. Our findings highlight the significance of GARP both in dissecting duality of Treg/Th17 cell differentiation and as a marker to identify bona fide Tregs during diseases with chronic immune activation.

Expression of GARP selectively identifies activated human FOXP3+ regulatory T cells

PubMed Central

Wang, Rui; Kozhaya, Lina; Mercer, Frances; Khaitan, Alka; Fujii, Hodaka; Unutmaz, Derya

2009-01-01

The molecules that define human regulatory T cells (Tregs) phenotypically and functionally remain to be fully characterized. We recently showed that activated human Tregs express mRNA for a transmembrane protein called glycoprotein A repetitions predominant (GARP, or LRRC32). Here, using a GARP-specific mAb, we demonstrate that expression of GARP on activated Tregs correlates with their suppressive capacity. However, GARP was not induced on T cells activated in the presence of TGFβ, which expressed high levels of FOXP3 and lacked suppressive function. Ectopic expression of FOXP3 in conventional T cells was also insufficient for induction of GARP expression in most donors. Functionally, silencing GARP in Tregs only moderately attenuated their suppressive activity. CD25+ T cells sorted for high GARP expression displayed more potent suppressive activity compared with CD25+GARP− cells. Remarkably, CD25+GARP− T cells expanded in culture contained 3–5 fold higher IL-17-secreting cells compared with either CD25+GARP+ or CD25−GARP− cells, suggesting that high GARP expression can potentially discriminate Tregs from those that have switched to Th17 lineage. We also determined whether GARP expression correlates with FOXP3-expressing T cells in human immunodeficiency virus (HIV) −infected subjects. A subset of HIV+ individuals with high percentages of FOXP3+ T cells did not show proportionate increase in GARP+ T cells. This finding suggests that higher FOXP3 levels observed in these HIV+ individuals is possibly due to immune activation rather than to an increase in Tregs. Our findings highlight the significance of GARP both in dissecting duality of Treg/Th17 cell differentiation and as a marker to identify bona fide Tregs during diseases with chronic immune activation. PMID:19666573

Overcoming food allergy through acquired tolerance conferred by transfer of Tregs in a murine model.

PubMed

Yamashita, H; Takahashi, K; Tanaka, H; Nagai, H; Inagaki, N

2012-02-01

The number of food allergy patients is increasing. Some children outgrow their food allergies through tolerance, whereas others remain susceptible throughout their lives. We aimed to contribute to food allergy therapeutics by understanding induction of oral tolerance in a murine food allergy model. We modified an existing murine food allergy model by using ovalbumin (OVA) to induce oral tolerance, either by pretreating mice with OVA or by transferring mesenteric lymph node (MLN) cells or T cells derived from mice treated with OVA. Pretreatment with OVA prevented food allergy, with complete suppression of OVA-specific immunoglobulin (Ig)E and IgA antibody production and interleukin (IL)-4, IL-10, and IL-9 mRNA expression. The proportion of regulatory T cells (Tregs) in MLN cells and expression of transforming growth factor-β mRNA increased. In the transfer model, anaphylaxis secondary to OVA intake was suppressed by transfer of whole MLN cells and Tregs from OVA-treated mice. However, OVA-specific IgE and IgA expressions were partially attenuated by transfer of antigen-specific and nonspecific Tregs, but not by whole MLN cells from OVA-treated mice. In the Treg transfer model, IL-4 and IL-10 mRNA expression decreased, but IL-9 mRNA expression increased. We concluded that oral tolerance for food antigens is induced in two ways: (i) by initial exposure to antigen, or inherent tolerance, and (ii) by transfer of Tregs, or acquired tolerance. Because food allergies occur when inherent tolerance is absent, understanding of acquired tolerance is important for the development of therapies for food allergy. © 2011 John Wiley & Sons A/S.

In Vitro Generation of IL-35-expressing Human Wharton's Jelly-derived Mesenchymal Stem Cells Using Lentiviral Vector.

PubMed

Amari, Afshin; Ebtekar, Massoumeh; Moazzeni, Seyed Mohammad; Soleimani, Masoud; Mohammadi Amirabad, Leila; Tahoori, Mohammad Taher; Massumi, Mohammad

2015-08-01

Human Wharton's Jelly-derived Mesenchymal Stem Cells (hWJ-MSCs) are easily available cells without transplant rejection problems or ethical concerns compared to bone-marrow-derived MSCs for prospective clinical applications. These cells display immunosuppressive properties and may be able to play an important role in autoimmune disorders. Regulatory T-cells (Treg) are important to prevent autoimmune disease development. Interleukin 35 (IL-35) induces the proliferation of Treg cell populations and reduces the activity of T helper 17 (Th17) and T helper 1 (Th1) cells, which play a central role in initiation of inflammation and autoimmune disease. Recent studies identified IL-35 as a new inhibitory cytokine required for the suppressive function of Treg cells. We created IL-35-producing hWJ-MSCs as a good vehicle for reduction of inflammation and autoimmune diseases. We isolated hWJ-MSCs based on explant culture. HWJ-MSCs were transduced at MOI=50 (Multiplicity of Infection) with lentiviral particles harboring murine Interleukin 35 (mIL-35). Expression of IL-35 in hWJ-MSCs was quantified by an IL-35 ELISA kit. IL-35 bioactivity was analyzed by inhibiting the proliferation of mouse splenocytes using CFSE cell proliferation kit. Frequency of CD4+CD25+CD127 low/neg Foxp3+ Treg cells was measured by flow cytometry. There was an up to 85% GFP positive transduction rate, and the cells successfully released a high level of mIL-35 protein (750 ng/ml). IL-35 managed to inhibit CD4+ T cell proliferation with PHA, and improved the frequency of Treg cells. Our data suggest that transduced hWJ-MSCs overexpressing IL-35 may provide a useful approach for basic research on gene therapy for autoimmune disorders.

Exacerbation of spontaneous autoimmune nephritis following regulatory T cell depletion in B cell lymphoma 2‐interacting mediator knock‐out mice

PubMed Central

Wang, Y. M.; Zhang, G. Y.; Wang, Y.; Hu, M.; Zhou, J. J.; Sawyer, A.; Cao, Q.; Wang, Y.; Zheng, G.; Lee, V. W. S.; Harris, D. C. H.

2017-01-01

Summary Regulatory T cells (Tregs) have been recognized as central mediators for maintaining peripheral tolerance and limiting autoimmune diseases. The loss of Tregs or their function has been associated with exacerbation of autoimmune disease. However, the temporary loss of Tregs in the chronic spontaneous disease model has not been investigated. In this study, we evaluated the role of Tregs in a novel chronic spontaneous glomerulonephritis model of B cell lymphoma 2‐interacting mediator (Bim) knock‐out mice by transient depleting Tregs. Bim is a pro‐apoptotic member of the B cell lymphoma 2 (Bcl‐2) family. Bim knock‐out (Bim–/–) mice fail to delete autoreactive T cells in thymus, leading to chronic spontaneous autoimmune kidney disease. We found that Treg depletion in Bim–/– mice exacerbated the kidney injury with increased proteinuria, impaired kidney function, weight loss and greater histological injury compared with wild‐type mice. There was a significant increase in interstitial infiltrate of inflammatory cells, antibody deposition and tubular damage. Furthermore, the serum levels of cytokines interleukin (IL)−2, IL‐4, IL‐6, IL‐10, IL‐17α, interferon (IFN)‐γ and tumour necrosis factor (TNF)‐α were increased significantly after Treg depletion in Bim–/– mice. This study demonstrates that transient depletion of Tregs leads to enhanced self‐reactive T effector cell function followed by exacerbation of kidney disease in the chronic spontaneous kidney disease model of Bim‐deficient mice. PMID:28152566

Notch1 Signaling Regulates the Th17/Treg Immune Imbalance in Patients with Psoriasis Vulgaris.

PubMed

Ma, Lei; Xue, HaiBo; Gao, Tianqin; Gao, MeiLan; Zhang, YuJie

2018-01-01

To evaluate the regulating effect of Notch1 signaling on Th17/Treg immune imbalance in psoriasis vulgaris (PV). Notch1, Hes-1, ROR γ t, Foxp3, IL-17, and IL-10 mRNA expression, as well as Th17 and Treg cell percentages in peripheral CD4 + T cells, were detected by real-time quantitative RT-PCR and flow cytometry, and serum concentrations of IL-17 and IL-10 were detected by ELISA in 36 PV patients and 32 healthy controls. Additionally, CD4 + T cells from 12 PV patients were treated with γ -secretase inhibitor DAPT, and the above indexes were measured. PV patients presented distinct Th17/Treg immune imbalance and highly expressed Notch1 and Hes-1 mRNA levels, which were positively correlated with psoriasis area and severity index (PASI) and the ratios of Th17/Treg and ROR γ t/Foxp3. DAPT treatment resulted in the obvious downregulation of Th17 cell percentage in cocultured CD4 + T cells, ROR γ t and IL-17 mRNA levels, and IL-17 concentration in cell-free supernatant from cocultured CD4 + T cells of PV patients in a dose-dependent manner, while there was no significant influence on Treg cell percentage, Foxp3, and IL-10 expression, therefore leading to the recovery of Th17/Treg immune imbalance. Notch1 signaling may contribute to the pathogenesis of PV by regulating Th17/Treg immune imbalance.

Complex Immune Evasion Strategies in Classical Hodgkin Lymphoma.

PubMed

Wein, Frederik; Weniger, Marc A; Höing, Benedikt; Arnolds, Judith; Hüttmann, Andreas; Hansmann, Martin-Leo; Hartmann, Sylvia; Küppers, Ralf

2017-12-01

The cellular microenvironment in classical Hodgkin lymphoma (cHL) is dominated by a mixed infiltrate of inflammatory cells with typically only about 1% Hodgkin and Reed/Sternberg (HRS) tumor cells. T cells are usually the largest population of cells in the cHL microenvironment, encompassing T helper (Th) cells, regulatory T cells (Tregs), and cytotoxic T cells. Th cells and Tregs presumably provide essential survival signals for HRS cells. Tregs are also involved in rescuing HRS cells from antitumor immune responses. An understanding of the immune evasion strategies of HRS cells is not only relevant for a characterization of the pathophysiology of cHL but is also clinically relevant, given the current treatment approaches targeting checkpoint inhibitors. Here, we characterized the cHL-specific CD4 + T-cell infiltrate regarding its role in immune evasion. Global gene expression analysis of CD4 + Th cells and Tregs isolated from cHL lymph nodes and reactive tonsils revealed that Treg signatures were enriched in CD4 + Th cells of cHL. Hence, HRS cells may induce Treg differentiation in Th cells, a conclusion supported by in vitro studies with Th cells and cHL cell lines. We also found evidence for immune-suppressive purinergic signaling and a role of the inhibitory receptor-ligand pairs B- and T-cell lymphocyte attenuator-herpesvirus entry mediator and CD200R-CD200 in promoting immune evasion. Taken together, this study highlights the relevance of Treg induction and reveals new immune checkpoint-driven immune evasion strategies in cHL. Cancer Immunol Res; 5(12); 1122-32. ©2017 AACR . ©2017 American Association for Cancer Research.

Promises and paradoxes of regulatory T cells in inflammatory bowel disease.

PubMed

Lord, James D

2015-10-28

Since their discovery two decades ago, CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) have become the subject of intense investigation by immunologists. Unlike other T cells, which promote an immune response, Tregs actively inhibit inflammation when activated by their cognate antigen, thus raising hope that these cells could be engineered into a highly targeted, antigen-specific, immunosuppressant therapy. Although Tregs represent less than 10% of circulating CD4(+)T cells, they have been shown to play an essential role in preventing or limiting inflammation in a variety of animal models and human diseases. In particular, spontaneous intestinal inflammation has been shown to occur in the absence of Tregs, suggesting that there may be a Treg defect central to the pathogenesis of human inflammatory bowel disease (IBD). However, over the past decade, multiple groups have reported no qualitative or quantitative deficits in Tregs from the intestines and blood of IBD patients to explain why these cells fail to regulate inflammation in Crohn's disease and ulcerative colitis. In this review, we will discuss the history of Tregs, what is known about them in IBD, and what progress and obstacles have been seen with efforts to employ them for therapeutic benefit.

Regulatory T Lymphocytes in Periodontitis: A Translational View

PubMed Central

2018-01-01

Periodontitis is a chronic immuno-inflammatory disease in which the disruption of the balance between host and microbiota interactions is key to the onset and progression of the disease. The immune homeostasis associated with periodontal health requires a regulated immuno-inflammatory response, during which the presence of regulatory T cells (Tregs) is essential to ensure a controlled response that minimizes collateral tissue damage. Since Tregs modulate both innate and adaptive immunity, pathological conditions that may resolve by the acquisition of immuno-tolerance, such as periodontitis, may benefit by the use of Treg immunotherapy. In recent years, many strategies have been proposed to take advantage of the immuno-suppressive capabilities of Tregs as immunotherapy, including the ex vivo and in vivo manipulation of the Treg compartment. Ongoing research in both basic and translational studies let us gain a better understanding of the diversity of Treg subsets, their phenotypic plasticity, and suppressive functions, which can be used as a substrate for new immunotherapies. Certainly, as our knowledge of Treg biology increases, we will be capable to develop new therapies designed to enhance the stability and function of Tregs during periodontitis.

Treatment with Cordyceps sinensis enriches Treg population in peripheral lymph nodes and delays type I diabetes development in NOD mice.

PubMed

Wang, Mei-Fen; Zhu, Qing-Hua; He, Yu-Gong

2013-09-01

Cordyceps sinensis is a widely used Chinese traditional herb with a long history. In China C. sinensis is usually applied in the treatment of respiratory diseases, however, the efficacy of C. sinensis still lacks experimental evidence. Type I diabetes is a multi-factor related autoimmune disease caused by cellular-mediated destruction of insulin-producing pancreatic beta cells in the islets in human. We tested C. sinensis for its ability to work as an immune modulator in NOD mice, an animal model which mimicks the progression of type I diabetes in humans and found that treatment with C. sinensis extract could slow down disease development in NOD mice. Further research also suggested that treatment with C. sinensis extract increased the frequency of Treg cells and IFN-gama producing Th1 cells in peripheral lymph nodes. However, C. sinensis has no effect on the natural Treg cell differentiation in thymus.

CD4+CD25+ regulatory T cells suppress allograft rejection mediated by memory CD8+ T cells via a CD30-dependent mechanism.

PubMed

Dai, Zhenhua; Li, Qi; Wang, Yinong; Gao, Ge; Diggs, Lonnette S; Tellides, George; Lakkis, Fadi G

2004-01-01

CD4(+)CD25(+) regulatory T (Treg) cells suppress naive T cell responses, prevent autoimmunity, and delay allograft rejection. It is not known, however, whether Treg cells suppress allograft rejection mediated by memory T cells, as the latter mount faster and stronger immune responses than their naive counterparts. Here we show that antigen-induced, but not naive, Treg cells suppress allograft rejection mediated by memory CD8(+) T cells. Suppression was allospecific, as Treg cells induced by third-party antigens did not delay allograft rejection. In vivo and in vitro analyses revealed that the apoptosis of allospecific memory CD8(+) T cells is significantly increased in the presence of antigen-induced Treg cells, while their proliferation remains unaffected. Importantly, neither suppression of allograft rejection nor enhanced apoptosis of memory CD8(+) T cells was observed when Treg cells lacked CD30 or when CD30 ligand-CD30 interaction was blocked with anti-CD30 ligand Ab. This study therefore provides direct evidence that pathogenic memory T cells are amenable to suppression in an antigen-specific manner and identifies CD30 as a molecule that is critical for the regulation of memory T cell responses.

CD4+CD25+ regulatory T cells suppress allograft rejection mediated by memory CD8+ T cells via a CD30-dependent mechanism

PubMed Central

Dai, Zhenhua; Li, Qi; Wang, Yinong; Gao, Ge; Diggs, Lonnette S.; Tellides, George; Lakkis, Fadi G.

2004-01-01

CD4+CD25+ regulatory T (Treg) cells suppress naive T cell responses, prevent autoimmunity, and delay allograft rejection. It is not known, however, whether Treg cells suppress allograft rejection mediated by memory T cells, as the latter mount faster and stronger immune responses than their naive counterparts. Here we show that antigen-induced, but not naive, Treg cells suppress allograft rejection mediated by memory CD8+ T cells. Suppression was allospecific, as Treg cells induced by third-party antigens did not delay allograft rejection. In vivo and in vitro analyses revealed that the apoptosis of allospecific memory CD8+ T cells is significantly increased in the presence of antigen-induced Treg cells, while their proliferation remains unaffected. Importantly, neither suppression of allograft rejection nor enhanced apoptosis of memory CD8+ T cells was observed when Treg cells lacked CD30 or when CD30 ligand–CD30 interaction was blocked with anti–CD30 ligand Ab. This study therefore provides direct evidence that pathogenic memory T cells are amenable to suppression in an antigen-specific manner and identifies CD30 as a molecule that is critical for the regulation of memory T cell responses. PMID:14722622

Adoptive cell therapy for lymphoma with CD4 T cells depleted of CD137-expressing regulatory T cells.

PubMed

Goldstein, Matthew J; Kohrt, Holbrook E; Houot, Roch; Varghese, Bindu; Lin, Jack T; Swanson, Erica; Levy, Ronald

2012-03-01

Adoptive immunotherapy with antitumor T cells is a promising novel approach for the treatment of cancer. However, T-cell therapy may be limited by the cotransfer of regulatory T cells (T(reg)). Here, we explored this hypothesis by using 2 cell surface markers, CD44 and CD137, to isolate antitumor CD4 T cells while excluding T(regs). In a murine model of B-cell lymphoma, only CD137(neg)CD44(hi) CD4 T cells infiltrated tumor sites and provided protection. Conversely, the population of CD137(pos)CD44hi CD4 T cells consisted primarily of activated T(regs). Notably, this CD137(pos) T(reg) population persisted following adoptive transfer and maintained expression of FoxP3 as well as CD137. Moreover, in vitro these CD137(pos) cells suppressed the proliferation of effector cells in a contact-dependent manner, and in vivo adding the CD137(pos)CD44(hi) CD4 cells to CD137(neg)CD44(hi) CD4 cells suppressed the antitumor immune response. Thus, CD137 expression on CD4 T cells defined a population of activated T(regs) that greatly limited antitumor immune responses. Consistent with observations in the murine model, human lymphoma biopsies also contained a population of CD137(pos) CD4 T cells that were predominantly CD25(pos)FoxP3(pos) T(regs). In conclusion, our findings identify 2 surface markers that can be used to facilitate the enrichment of antitumor CD4 T cells while depleting an inhibitory T(reg) population.

Metabolites produced by commensal bacteria promote peripheral regulatory T-cell generation.

PubMed

Arpaia, Nicholas; Campbell, Clarissa; Fan, Xiying; Dikiy, Stanislav; van der Veeken, Joris; deRoos, Paul; Liu, Hui; Cross, Justin R; Pfeffer, Klaus; Coffer, Paul J; Rudensky, Alexander Y

2013-12-19

Intestinal microbes provide multicellular hosts with nutrients and confer resistance to infection. The delicate balance between pro- and anti-inflammatory mechanisms, essential for gut immune homeostasis, is affected by the composition of the commensal microbial community. Regulatory T cells (Treg cells) expressing transcription factor Foxp3 have a key role in limiting inflammatory responses in the intestine. Although specific members of the commensal microbial community have been found to potentiate the generation of anti-inflammatory Treg or pro-inflammatory T helper 17 (TH17) cells, the molecular cues driving this process remain elusive. Considering the vital metabolic function afforded by commensal microorganisms, we reasoned that their metabolic by-products are sensed by cells of the immune system and affect the balance between pro- and anti-inflammatory cells. We tested this hypothesis by exploring the effect of microbial metabolites on the generation of anti-inflammatory Treg cells. We found that in mice a short-chain fatty acid (SCFA), butyrate, produced by commensal microorganisms during starch fermentation, facilitated extrathymic generation of Treg cells. A boost in Treg-cell numbers after provision of butyrate was due to potentiation of extrathymic differentiation of Treg cells, as the observed phenomenon was dependent on intronic enhancer CNS1 (conserved non-coding sequence 1), essential for extrathymic but dispensable for thymic Treg-cell differentiation. In addition to butyrate, de novo Treg-cell generation in the periphery was potentiated by propionate, another SCFA of microbial origin capable of histone deacetylase (HDAC) inhibition, but not acetate, which lacks this HDAC-inhibitory activity. Our results suggest that bacterial metabolites mediate communication between the commensal microbiota and the immune system, affecting the balance between pro- and anti-inflammatory mechanisms.

Foxp3+ regulatory T cells impede the priming of protective CD8+ T cells

PubMed Central

Ertelt, James M.; Rowe, Jared H.; Mysz, Margaret A.; Singh, Charanjeet; Roychowdhury, Monika; Aguilera, Marijo N.; Way, Sing Sing

2011-01-01

T cell activation is controlled by incompletely defined opposing stimulation and suppression signals that together sustain the balance between optimal host defense against infection and peripheral tolerance. Herein, we explored the impacts of Foxp3+ regulatory T cell (Treg) suppression in priming antigen-specific T cell activation under non-infection and infection conditions. We find the transient ablation of Foxp3+ Tregs unleashes the robust expansion and activation of peptide stimulated CD8+ T cells that provide protection against Listeria monocytogenes (Lm) infection in an antigen-specific fashion. By contrast, Treg-ablation had non-significant impacts on the CD8+ T cell response primed by infection with recombinant Lm. Similarly, non-recombinant Lm administered with peptide stimulated the expansion and activation of CD8+ T cells that paralleled the response primed by Treg-ablation. Interestingly, these adjuvant properties of Lm did not require CD8+ T cell stimulation by IL-12 produced in response to infection, but instead were associated with sharp reductions in Foxp3+ Treg suppressive potency. Therefore, Foxp3+ Tregs impose critical barriers that when overcome naturally during infection or artificially with ablation allows the priming of protective antigen-specific CD8+ T cells. PMID:21810602

Cutting edge: Th17 and regulatory T cell dynamics and the regulation by IL-2 in the tumor microenvironment.

PubMed

Kryczek, Ilona; Wei, Shuang; Zou, Linhua; Altuwaijri, Saleh; Szeliga, Wojciech; Kolls, Jay; Chang, Alfred; Zou, Weiping

2007-06-01

Th17 cells play an active role in inflammation and autoimmune diseases. However, the nature and regulation of Th17 in the context of tumor immunity remain unknown. In this study, we show that parallel to regulatory T (Treg) cells, IL-17(+) CD4(+) and CD8(+) T cells are kinetically induced in multiple tumor microenvironments in mice and humans. Treg cells play a crucial role in tumor immune pathogenesis and temper immune therapeutic efficacy. IL-2 is crucial for the production and function of Treg cells. We now show that IL-2 reduces IL-17(+) T cell differentiation in the tumor microenvironment accompanied with an enhanced Treg cell compartment in vitro and in vivo. Altogether, our work demonstrates a dynamic differentiation of IL-17(+) T cells in the tumor microenvironment, reveals a novel role for IL-2 in controlling the balance between IL-17(+) and Treg cells, and provides new insight of IL-17(+) T cells in tumor immune pathology and therapy.

Disruption of CCR5-dependent homing of regulatory T cells inhibits tumor growth in a murine model of pancreatic cancer

PubMed Central

Tan, Marcus C. B.; Goedegebuure, Peter S.; Belt, Brian A.; Flaherty, Brian; Sankpal, Narendra; Gillanders, William E.; Eberlein, Timothy J.; Hsieh, Chyi-Song; Linehan, David C.

2013-01-01

Tumors evade immune destruction by actively inducing immune tolerance through the recruitment of CD4+CD25+Foxp3+ regulatory T cells (Treg). We have previously described increased prevalence of these cells in pancreatic adenocarcinoma, but it remains unclear what mechanisms are involved in recruiting Treg into the tumor microenvironment. Here, we postulated that chemokines might direct Treg homing to tumor. We show, in both human pancreatic adenocarcinoma and a murine pancreatic tumor model (Pan02), that tumor cells produce increased levels of ligands for the CCR5 chemokine receptor, and, reciprocally, that CD4+ Foxp3+ Treg, compared with CD4+ Foxp3− effector T cells, preferentially express CCR5. When CCR5/CCL5 signaling is disrupted, either by reducing CCL5 production by tumor cells or by systemic administration of a CCR5 inhibitor (TAK-779), Treg migration to tumors is reduced and tumors are smaller than in control mice. Thus, this study demonstrates the importance of Treg in immune evasion by tumors, how blockade of Treg migration may inhibit tumor growth, and, specifically in pancreatic adenocarcinoma, the role of CCR5 in the homing of tumor-associated Treg. Selective targeting of CCR5/CCL5 signaling may represent a novel immunomodulatory strategy for the treatment of cancer. PMID:19155524

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

PubMed

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.

Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID

PubMed Central

Sauer, Aisha V.; Brigida, Immacolata; Carriglio, Nicola; Jofra Hernandez, Raisa; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L.; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna

2012-01-01

Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)–mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA–treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA−/− Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA–treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA–treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID. Trials were registered at www.clinicaltrials.gov as NCT00598481/NCT00599781. PMID:22184407

Immunosuppressive Environment in Basal Cell Carcinoma: The Role of Regulatory T Cells.

PubMed

Omland, Silje H; Nielsen, Patricia S; Gjerdrum, Lise M R; Gniadecki, Robert

2016-11-02

Interaction between tumour survival tactics and anti-tumour immune response is a major determinant for cancer growth. Regulatory T cells (T-regs) contribute to tumour immune escape, but their role in basal cell carcinoma (BCC) is not understood. The fraction of T-regs among T cells was analysed by immunohistochemistry followed by automated image analysis in facial BCC, peritumoural skin and normal, buttock skin. Quantitative real-time PCR (qRT-PCR) was performed for FOXP3 and cytokines involved in T-reg attraction and T-cell activation. T-regs comprised 45% of CD4-cells surrounding BCC. FOXP3 was highly expressed in BCC, but absent in buttock skin. Unexpectedly, expression of FOXP3 was increased in peritumoural skin, with the FOXP3/CD3 fractions exceeding those of BCC (p?=?0.0065). Transforming growth factor (TGF)-? and T-reg chemokine expression was increased in BCC and peritumoural skin, but not in buttock skin, with expression levels correlating with FOXP3. T-regs are abundantly present both in BCC and in peritumoural skin, mediating an immunosuppressed microenvironment permissive for skin cancer.

Alteration of Th17 and Treg cell subpopulations co-exist in patients affected with systemic sclerosis.

PubMed

Fenoglio, Daniela; Battaglia, Florinda; Parodi, Alessia; Stringara, Silvia; Negrini, Simone; Panico, Nicoletta; Rizzi, Marta; Kalli, Francesca; Conteduca, Giuseppina; Ghio, Massimo; De Palma, Raffaele; Indiveri, Francesco; Filaci, Gilberto

2011-06-01

Aim of the study has been to understand the relationship between TH17 and Treg cell subsets in patients affected with systemic sclerosis (SSc). Phenotypes and functions of Th17 and Treg cell subsets were analyzed in a series of 36 SSc patients. Th17 cell concentration in the peripheral blood was found to be increased in SSc patients with respect to healthy controls independently from type or stage of disease. After PBMC stimulation with a polyclonal stimulus or Candida albicans antigens the frequency of Th17 T cell clones was significantly higher in SSc patients with respect to controls suggesting the skewing of immune response in SSc patients toward Th17 cell generation/expansion. Concerning the Treg compartment, both CD4+CD25+ and CD8+CD28- Treg subsets showed quantitative and qualitative alteration in the peripheral blood of SSc patients. Collectively, these data highlight the existence of an imbalanced ratio between Th17 and Treg cell subsets in SSc patients. Copyright © 2011 Elsevier Inc. All rights reserved.

CD(+)(4)CD(+)(25) Treg cells in thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus patients.

PubMed

Huang, Hongdong; Sun, Weiming; Liang, Yumei; Long, Xi-Dai; Peng, Youming; Liu, Zhihua; Wen, Xiaojun; Jia, Meng

2014-09-01

CD(+)(4)CD(+)(25) Treg cells are of critical importance for maintenance of tolerance. The purpose of the this study was to observe the number of CD(+)(4)CD(+)(25) Treg cells in the patients with thrombotic thrombocytopenic purpura (TTP) associated with systemic lupus erythematosus (SLE), and to study pathogenesis of TTP with SLE. Seven patients with TTP associated with SLE and seven healthy volunteers were studied. The CD(+)(4)CD(+)(25) Treg cells were examined by flow cytometry. Clinical and laboratory data, such as urinary protein, serum creatinine, endothelial markers and immunologic serologics, were obtained from each patient and healthy volunteer. Glomerular injury was assessed by histopathology. Serum IL-2, IL-4, IL-6 and anti-endothelial cell antibody were analyzed by ELISA and anti-ADAMTS13 antibody were detected by Western blotting. CD(+)(4)CD(+)(25) Treg cells significantly decreased in TTP with SLE patients compared with controls (p < 0.05). CD(+)(4)CD(+)(25) Treg cells are negatively correlated with blood urea nitrogen, serum uric acid, supernatant IL-4, and proteinuria, and positively with estimated glomerular filtration rate (eGFR) in TTP with SLE patients. [Formula: see text] Treg cells gradually decreased as the severity of renal histology increased. Serum IL-2, IL-6, supernatant IL-4, anti-endothelial cell antibody, and anti-ADAMTS13 antibody significantly increased in TTP with SLE patients compared to those of the control groups (all p < 0.05). In contrast, serum levels of C3 were significantly decreased in TTP with SLE patients compared to those of the control groups (p < 0.05). CD(+)(4)CD(+)(25) Treg cells are not only lower in TTP with SLE patients, but also are correlated with disease severity in TTP with SLE patients.CD(+)(4)CD(+)(25)Treg cells may play an important role in the pathogenesis of TTP with SLE.

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

PubMed Central

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

2015-01-01

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. PMID:26343373

Effects of iodine-131 radiotherapy on Th17/Tc17 and Treg/Th17 cells of patients with differentiated thyroid carcinoma.

PubMed

Zhang, Lixia; Chen, Jinyan; Xu, Caiyun; Qi, Lili; Ren, Yan

2018-03-01

T helper 17 (Th17), T cytotoxic 17 (Tc17) and regulatory T (Treg) cells serve important roles in a number of inflammatory and autoimmune diseases. The aim of the present study was to examine the distribution of Th17, Tc17 and Treg cells in patients with differentiated thyroid cancer (DTC) prior to as well as 7, 30 and 90 days following radioactive iodine-131 ( 131 I) therapy, and to elucidate the probable effects of 131 I therapy on Th17/Tc17 and Treg/Th17 cells in patients with DTC. A total of 40 patients with DTC (26 female; 14 male) between the ages of 24 and 72 years, as well as 13 age- and sex-matched healthy subjects were included in this study. The number of Th17, Tc17 and Treg cells in the peripheral blood of patients with DTC and of healthy Controls were assessed by flow cytometry. Th17 and Tc17 cells were counted as percentages of the number of CD3 + T cells; Treg cells were counted as a percentage of the number of CD4 + T cells. In addition, the serum levels of interleukin (IL)-17, IL-23, IL-10 and transforming growth factor (TGF)-β1 were examined by ELISA. The frequencies of Th17, Tc17 and Treg cells, as well as the serum levels of IL-17, IL-23, IL-10 and TGF-β1 were significantly elevated in patients with DTC compared with healthy Controls, whereas 131 I therapy significantly decreased them. In addition, elevated Th17/Tc17 ratio and reduced Treg/Th17 ratio were observed in patients with DTC at day 0, however, these ratios returned to normal levels following 131 I therapy for 90 days as compared with healthy Controls. Notably, Th17/Tc17 and Treg/Th17 ratios varied following 131 I therapy for 7 and 30 days. In addition, a strong positive correlation between Th17 and Tc17 cells was observed in the healthy Controls and patients with DTC that received 131 I treatment for 90 days, whereas a weak positive correlation between Th17 and Treg cell levels was identified in the healthy Controls and no obvious correlation between Th17 and Treg cells was observed in all patients with DTC pre- and post- 131 I therapy during the entire treatment period. These data suggested a significant involvement of Th17, Tc17 and Treg cells in the pathology of DTC. Restoring the balance of these cells may contribute to the recovery of patients with DTC following 131 I therapy.

NADPH oxidase deficiency underlies dysfunction of aged CD8+ Tregs

PubMed Central

Wen, Zhenke; Shimojima, Yasuhiro; Shirai, Tsuyoshi; Li, Yinyin; Ju, Jihang; Yang, Zhen; Tian, Lu; Goronzy, Jörg J.

2016-01-01

Immune aging results in progressive loss of both protective immunity and T cell–mediated suppression, thereby conferring susceptibility to a combination of immunodeficiency and chronic inflammatory disease. Here, we determined that older individuals fail to generate immunosuppressive CD8+CCR7+ Tregs, a defect that is even more pronounced in the age-related vasculitic syndrome giant cell arteritis. In young, healthy individuals, CD8+CCR7+ Tregs are localized in T cell zones of secondary lymphoid organs, suppress activation and expansion of CD4 T cells by inhibiting the phosphorylation of membrane-proximal signaling molecules, and effectively inhibit proliferative expansion of CD4 T cells in vitro and in vivo. We identified deficiency of NADPH oxidase 2 (NOX2) as the molecular underpinning of CD8 Treg failure in the older individuals and in patients with giant cell arteritis. CD8 Tregs suppress by releasing exosomes that carry preassembled NOX2 membrane clusters and are taken up by CD4 T cells. Overexpression of NOX2 in aged CD8 Tregs promptly restored suppressive function. Together, our data support NOX2 as a critical component of the suppressive machinery of CD8 Tregs and suggest that repairing NOX2 deficiency in these cells may protect older individuals from tissue-destructive inflammatory disease, such as large-vessel vasculitis. PMID:27088800

Bifidobacterium breve attenuates murine dextran sodium sulfate-induced colitis and increases regulatory T cell responses.

PubMed

Zheng, Bin; van Bergenhenegouwen, Jeroen; Overbeek, Saskia; van de Kant, Hendrik J G; Garssen, Johan; Folkerts, Gert; Vos, Paul; Morgan, Mary E; Kraneveld, Aletta D

2014-01-01

While some probiotics have shown beneficial effects on preventing or treating colitis development, others have shown no effects. In this study, we have assessed the immunomodulating effects of two probiotic strains, Lactobacillus rhamnosus (L. rhamnosus) and Bifidobacterium breve (B. breve) on T cell polarization in vitro, using human peripheral blood mononuclear cells (PBMC), and in vivo, using murine dextran sodium sulfate (DSS) colitis model. With respect to the latter, the mRNA expression of T cell subset-associated transcription factors and cytokines in the colon was measured and the T helper type (Th) 17 and regulatory T cell (Treg) subsets were determined in the Peyer's patches. Both L. rhamnosus and B. breve incubations in vitro reduced Th17 and increased Th2 cell subsets in human PBMCs. In addition, B. breve incubation was also able to reduce Th1 and increase Treg cell subsets in contrast to L. rhamnosus. In vivo intervention with B. breve, but not L. rhamnosus, significantly attenuated the severity of DSS-induced colitis. In DSS-treated C57BL/6 mice, intervention with B. breve increased the expression of mRNA encoding for Th2- and Treg-associated cytokines in the distal colon. In addition, intervention with B. breve led to increases of Treg and decreases of Th17 cell subsets in Peyer's patches of DSS-treated mice. B. breve modulates T cell polarization towards Th2 and Treg cell-associated responses in vitro and in vivo. In vivo B. breve intervention ameliorates DSS-induced colitis symptoms and this protective effect may mediated by its effects on the T-cell composition.

Bifidobacterium breve Attenuates Murine Dextran Sodium Sulfate-Induced Colitis and Increases Regulatory T Cell Responses

PubMed Central

Zheng, Bin; van Bergenhenegouwen, Jeroen; Overbeek, Saskia; van de Kant, Hendrik J. G.; Garssen, Johan; Folkerts, Gert; Vos, Paul; Morgan, Mary E.; Kraneveld, Aletta D.

2014-01-01

While some probiotics have shown beneficial effects on preventing or treating colitis development, others have shown no effects. In this study, we have assessed the immunomodulating effects of two probiotic strains, Lactobacillus rhamnosus (L. rhamnosus) and Bifidobacterium breve (B. breve) on T cell polarization in vitro, using human peripheral blood mononuclear cells (PBMC), and in vivo, using murine dextran sodium sulfate (DSS) colitis model. With respect to the latter, the mRNA expression of T cell subset-associated transcription factors and cytokines in the colon was measured and the T helper type (Th) 17 and regulatory T cell (Treg) subsets were determined in the Peyer's patches. Both L. rhamnosus and B. breve incubations in vitro reduced Th17 and increased Th2 cell subsets in human PBMCs. In addition, B. breve incubation was also able to reduce Th1 and increase Treg cell subsets in contrast to L. rhamnosus. In vivo intervention with B. breve, but not L. rhamnosus, significantly attenuated the severity of DSS-induced colitis. In DSS-treated C57BL/6 mice, intervention with B. breve increased the expression of mRNA encoding for Th2- and Treg-associated cytokines in the distal colon. In addition, intervention with B. breve led to increases of Treg and decreases of Th17 cell subsets in Peyer's patches of DSS-treated mice. B. breve modulates T cell polarization towards Th2 and Treg cell-associated responses in vitro and in vivo. In vivo B. breve intervention ameliorates DSS-induced colitis symptoms and this protective effect may mediated by its effects on the T-cell composition. PMID:24787575

Frequency of regulatory T cells determines the outcome of the T-cell-engaging antibody blinatumomab in patients with B-precursor ALL.

PubMed

Duell, J; Dittrich, M; Bedke, T; Mueller, T; Eisele, F; Rosenwald, A; Rasche, L; Hartmann, E; Dandekar, T; Einsele, H; Topp, M S

2017-10-01

Blinatumomab can induce a complete haematological remission in patients in 46.6% with relapsed/refractory B-precursor acute lymphoblastic leukemia (r/r ALL) resulting in a survival benefit when compared with chemotherapy. Only bone marrow blast counts before therapy have shown a weak prediction of response. Here we investigated the role of regulatory T cells (Tregs), measured by CD4/CD25/FOXP3 expression, in predicting the outcome of immunotherapy with the CD19-directed bispecific T-cell engager construct blinatumomab. Blinatumomab responders (n=22) had an average of 4.82% Tregs (confidence interval (CI): 1.79-8.34%) in the peripheral blood, whereas non-responders (n=20) demonstrated 10.25% Tregs (CI: 3.36-65.9%). All other tested markers showed either no prediction value or an inferior prediction level including blast BM counts and the classical enzyme marker lactate dehydrogenase. With a cutoff of 8.525%, Treg enumeration can identify 100% of all blinatumomab responders and exclude 70% of the non-responders. The effect is facilitated by blinatumomab-activated Tregs, leading to interleukin-10 production, resulting in suppression of T-cell proliferation and reduced CD8-mediated lysis of ALL cells. Proliferation of patients' T cells can be restored by upfront removal of Tregs. Thus, enumeration of Treg identifies r/r ALL patients with a high response rate to blinatumomab. Therapeutic removal of Tregs may convert blinatumomab non-responders to responders.

Curcumin up regulates T helper 1 cells in patients with colon cancer.

PubMed

Xu, Bin; Yu, Lin; Zhao, Li-Zhong

2017-01-01

The therapy for the advanced colon cancer (Cca) is unsatisfactory currently. To regulate the immune effector cell function has shown a positive effect on the treatment of advanced cancers. This study tests a hypothesis that administration with curcumin converts the Cca patient-derived regulatory T cells (Treg) to T helper (Th) 1 cells. In this study, a group of patients with advanced Cca was recruited into this study. The patients were treated with curcumin. The peripheral Tregs and Th1 cells were assessed by flow cytometry. The results showed that, after the curcumin therapy, the forkhead box protein (Foxp) 3 positive Treg frequency was markedly reduced, the frequency of Th1 cells was significantly increased in Cca patients. Treating with curcumin repressed the Foxp3 gene transcription in Tregs; the Tregs were then converted into Th1 cells. The results also revealed that Foxp3 bound T-bet to prevent IFN-γ expression in CD4 + T cells, which was abolished by treating with curcumin. In conclusion, the administration of curcumin can convert Tregs to Th1 cells via repressing Foxp3 expression and enhancing IFN-γ production.

Instability of Helios-deficient Tregs is associated with conversion to a T-effector phenotype and enhanced antitumor immunity.

PubMed

Nakagawa, Hidetoshi; Sido, Jessica M; Reyes, Edwin E; Kiers, Valerie; Cantor, Harvey; Kim, Hye-Jung

2016-05-31

Expression of the transcription factor Helios by Tregs ensures stable expression of a suppressive and anergic phenotype in the face of intense inflammatory responses, whereas Helios-deficient Tregs display diminished lineage stability, reduced FoxP3 expression, and production of proinflammatory cytokines. Here we report that selective Helios deficiency within CD4 Tregs leads to enhanced antitumor immunity through induction of an unstable phenotype and conversion of intratumoral Tregs into T effector cells within the tumor microenvironment. Induction of an unstable Treg phenotype is associated with enhanced production of proinflammatory cytokines by tumor-infiltrating but not systemic Tregs and significantly delayed tumor growth. Ab-dependent engagement of Treg surface receptors that result in Helios down-regulation also promotes conversion of intratumoral but not systemic Tregs into T effector cells and leads to enhanced antitumor immunity. These findings suggest that selective instability and conversion of intratumoral CD4 Tregs through genetic or Ab-based targeting of Helios may represent an effective approach to immunotherapy.

Clinical grade isolation of regulatory T cells from G-CSF mobilized peripheral blood improves with initial depletion of monocytes

PubMed Central

Patel, Pritesh; Mahmud, Dolores; Park, Youngmin; Yoshinaga, Kazumi; Mahmud, Nadim; Rondelli, Damiano

2015-01-01

Clinical isolation of circulating CD4+CD25+ regulatory T cells (Tregs) from peripheral blood mononuclear cells is usually performed by CD4+ cell negative selection followed by CD25+ cell positive selection. Although G-CSF mobilized peripheral blood (G-PBSC) contains a high number of Tregs, a high number of monocytes in G-PBSC limits Treg isolation. Using a small scale device (MidiMACS, Miltenyi) we initially demonstrated that an initial depletion of monocytes would be necessary to obtaina separation of CD4+CD25+FoxP3+CD127- cells from G-PBSC (G-Tregs) with a consistent purity >70% and inhibitory activity of T cell alloreactivity in-vitro. We then validated the same approach in a clinical scale setting by separating G-Tregs with clinically available antibodies to perform a CD8+CD19+CD14+ cell depletion followed by CD25+ cell selection (2-step process) or by adding an initial CD14+ cell depletion (3-step process) using a CliniMACS column. The 3-step approach resulted in a better purity (81±12% vs. 35±33%) and yield (66% vs. 39%). Clinically isolated G-Tregs were also FoxP3+CD127dim and functionally suppressive in-vitro. Our findings suggest that a better and more consistent purity of Tregs can be achieved from G-PBSC by an initial single depletion of monocytes prior to selection of CD4+CD25+ cells. PMID:27069755

Impairment of regulatory capacity of CD4+CD25+ regulatory T cells mediated by dendritic cell polarization and hyperthyroidism in Graves' disease.

PubMed

Mao, Chaoming; Wang, Shu; Xiao, Yichuan; Xu, Jingwei; Jiang, Qian; Jin, Min; Jiang, Xiaohua; Guo, Hua; Ning, Guang; Zhang, Yanyun

2011-04-15

Graves' disease (GD) is one of the most common autoimmune diseases. The immune dysfunction in GD involves the generation of thyroid-stimulating hormone receptor (TSHR) autoantibodies that presumably arise consequent to interactions among dendritic cells (DCs), T cells, and regulatory T (Treg) cells. However, the immunological mechanisms of interactions between them that lead to the induction and regulation of this autoimmune disease are poorly defined. In this study, we investigated whether DCs are the main cause of the defective activity of Treg cells in GD patients. We found a significant decrease in the percentage of circulating CD4(+)CD25(+)FOXP3(+) Treg cells in untreated GD patients (uGD), which was negatively correlated with the concentration of TSHR autoantibodies. uGD-derived DCs were polarized to increase the number of plasmacytoid DCs (pDCs) and conferred the ability to abrogate the suppressive function of Treg cells through inducing apoptosis of CD4(+)CD25(+) Treg cells in an IFN-α-dependent manner, and elevated thyroid hormones further exacerbated the effect. The nucleotide UDP, which inhibits IFN-α secretion of pDCs through P2Y6 receptor signaling, restored the suppressive function of CD4(+)CD25(+) Treg cells. Collectively, uGD-derived DCs through pDC polarization and elevated thyroid hormones act in concert to impair the regulatory capacity of Treg cells, facilitating the production of TSHR autoantibodies in the pathogenesis of GD.

Administration of CD4+CD25highCD127- regulatory T cells preserves β-cell function in type 1 diabetes in children.

PubMed

Marek-Trzonkowska, Natalia; Mysliwiec, Malgorzata; Dobyszuk, Anita; Grabowska, Marcelina; Techmanska, Ilona; Juscinska, Jolanta; Wujtewicz, Magdalena A; Witkowski, Piotr; Mlynarski, Wojciech; Balcerska, Anna; Mysliwska, Jolanta; Trzonkowski, Piotr

2012-09-01

Type 1 diabetes is a condition in which pancreatic islets are destroyed by self-reactive T cells. The process is facilitated by deficits in the number and suppressive activity of regulatory T cells (Tregs). Here, we show for the first time that the infusion of autologous Tregs prolongs remission in recently diagnosed type 1 diabetes in children. We have administered Tregs in 10 type 1 diabetic children (aged 8-16 years) within 2 months since diagnosis. In total, 4 patients received 10 × 10(6) Tregs/kg body wt, and the remaining 6 patients received 20 × 10(6) Tregs/kg body wt. The preparation consisted of sorted autologous CD3(+)CD4(+)CD25(high)CD127(-) Tregs expanded under good manufacturing practice conditions. No toxicity of the therapy was noted. A significant increase in the percentage of Tregs in the peripheral blood has been observed since the day of infusion. These patients were followed along with matched type 1 diabetic patients not treated with Tregs. Half a year after type 1 diabetes onset (4-5 months after Tregs infusion), 8 patients treated with Tregs still required <0.5 UI/kg body wt of insulin daily, with 2 patients out of insulin completely, whereas the remission was over in the nontreated group. In addition, plasma C-peptide levels were significantly higher in the treated group as compared with those not treated. This study shows that the administration of Tregs is safe and tolerable in children with recent-onset type 1 diabetes.

Effects of natalizumab treatment on Foxp3+ T regulatory cells.

PubMed

Stenner, Max-Philipp; Waschbisch, Anne; Buck, Dorothea; Doerck, Sebastian; Einsele, Hermann; Toyka, Klaus V; Wiendl, Heinz

2008-10-06

Natalizumab, a monoclonal humanized antibody targeting the alpha-4 chain of very late activation antigen 4 (VLA-4) exerts impressive therapeutic effects in patients with relapsing-remitting multiple sclerosis. Our objective was to study impacts of Natalizumab therapy on Foxp3+ T regulatory cells (Tregs) in multiple sclerosis (MS) patients. A combined approach of in vitro and ex vivo experiments using T cells isolated from the peripheral blood of healthy donors and Natalizumab treated MS patients was chosen. We determined binding of Natalizumab and its effects on the frequency, transmigratory behaviour and suppressive function of Tregs. Binding of Natalizumab and expression of CD49d (alpha-4 chain of VLA-4) differed between non-regulatory and regulatory cells. Albeit Foxp3+ Tregs had lower levels of CD49d, Natalizumab blocked the transmigration of Foxp3+ Tregs similar to non-regulatory T cells. The frequency of peripheral blood Tregs was unaffected by Natalizumab treatment. Natalizumab does not alter the suppressive capacity of CD4+CD25(high)CD127(low)Foxp3+ Tregs under in vitro conditions. Furthermore, the impaired function of Tregs in MS patients is not restored by Natalizumab treatment. We provide a first detailed analysis of Natalizumab effects on the regulatory T cell population. Our prospective study shows that Foxp3+ Tregs express lower levels of VLA-4 and bind less Natalizumab. We further the understanding of the mechanisms of action of Natalizumab by demonstrating that unlike other immunomodulatory drugs the beneficial therapeutic effects of the monoclonal antibody are largely independent of alterations in Treg frequency or function.

Effects of Natalizumab Treatment on Foxp3+ T Regulatory Cells

PubMed Central

Buck, Dorothea; Doerck, Sebastian; Einsele, Hermann; Toyka, Klaus V.; Wiendl, Heinz

2008-01-01

Background Natalizumab, a monoclonal humanized antibody targeting the alpha-4 chain of very late activation antigen 4 (VLA-4) exerts impressive therapeutic effects in patients with relapsing-remitting multiple sclerosis. Our objective was to study impacts of Natalizumab therapy on Foxp3+ T regulatory cells (Tregs) in multiple sclerosis (MS) patients. Methodology A combined approach of in vitro and ex vivo experiments using T cells isolated from the peripheral blood of healthy donors and Natalizumab treated MS patients was chosen. We determined binding of Natalizumab and its effects on the frequency, transmigratory behaviour and suppressive function of Tregs. Principal Findings Binding of Natalizumab and expression of CD49d (alpha-4 chain of VLA-4) differed between non-regulatory and regulatory cells. Albeit Foxp3+ Tregs had lower levels of CD49d, Natalizumab blocked the transmigration of Foxp3+ Tregs similar to non-regulatory T cells. The frequency of peripheral blood Tregs was unaffected by Natalizumab treatment. Natalizumab does not alter the suppressive capacity of CD4+CD25highCD127lowFoxp3+ Tregs under in vitro conditions. Furthermore, the impaired function of Tregs in MS patients is not restored by Natalizumab treatment. Conclusions We provide a first detailed analysis of Natalizumab effects on the regulatory T cell population. Our prospective study shows that Foxp3+ Tregs express lower levels of VLA-4 and bind less Natalizumab. We further the understanding of the mechanisms of action of Natalizumab by demonstrating that unlike other immunomodulatory drugs the beneficial therapeutic effects of the monoclonal antibody are largely independent of alterations in Treg frequency or function. PMID:18836525

Protein-bound polysaccharide-K reduces the proportion of regulatory T cells in vitro and in vivo.

PubMed

Aoki, Rieko; Iijima, Hiroko; Kato, Mariko; Uchida, Motoyuki; Wada, Tsutomu; Murata, Masatsune; Ogawa, Kenji; Naritaka, Yoshihiko; Yoshimatsu, Kazuhiko

2014-01-01

Regulatory T cells (Tregs) play an important role in maintaining immunological tolerance. However, this mechanism is one of the major obstacles to overcome when attempting to improve antitumor immunity. Protein-bound polysaccharide‑K (PSK) has been used clinically as an antitumor drug, and one of its antitumor mechanisms involves improvement of the tumor-induced immunosuppressive state. Therefore, we investigated whether PSK affects Tregs in vitro and in vivo. In the in vitro study, CD4⁺CD25⁻ cells were separated from normal mouse spleen and cultured with or without PSK in the presence of TGF-β. Although TGF-β induced CD4⁺CD25⁺Foxp3⁺ Tregs, PSK reduced the proportion of TGF-β-induced Tregs. In the in vivo study, BALB/c mice were injected subcutaneously with methylcholanthrene-induced fibrosarcoma (Meth A) cells on day 0, and were administered PSK (50 mg/kg) intraperitoneally from day 1, three times per week. After 4 weeks, the tumor volume, the proportion of Tregs and the CD8+/Treg ratio in the spleen, plasma TGF-β concentration, and IFN-γ production by spleen cells were measured. PSK significantly reduced tumor growth, the proportion of Tregs in the spleen and the plasma TGF-β concentration, and significantly increased the CD8+/Treg ratio in the spleen and IFN-γ production by spleen cells. The reduction of the TGF-β concentration in blood by PSK appears to decrease the proportion of Tregs in lymphoid organs and to augment antitumor immunity.

Therapeutic regulatory T-cell adoptive transfer ameliorates established murine chronic GVHD in a CXCR5-dependent manner

PubMed Central

McDonald-Hyman, Cameron; Flynn, Ryan; Panoskaltsis-Mortari, Angela; Peterson, Nicholas; MacDonald, Kelli P. A.; Hill, Geoffrey R.; Luznik, Leo; Serody, Jonathan S.; Murphy, William J.; Maillard, Ivan; Munn, David H.; Turka, Laurence A.; Koreth, John; Cutler, Corey S.; Soiffer, Robert J.; Antin, Joseph H.; Ritz, Jerome

2016-01-01

Chronic graft-versus-host disease (cGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation. In cGVHD, alloreactive T cells and germinal center (GC) B cells often participate in GC reactions to produce pathogenic antibodies. Although regulatory T cells (Tregs) can inhibit GC reactions, Treg numbers are reduced in cGVHD, contributing to cGVHD pathogenesis. Here, we explored 2 means to increase Tregs in cGVHD: interleukin-2/monoclonal antibody (IL-2/mAb) complexes and donor Treg infusions. IL-2/mAb complexes given over 1 month were efficacious in expanding Tregs and treating established cGVHD in a multi-organ-system disease mouse model characterized by GC reactions, antibody deposition, and lung dysfunction. In an acute GVHD (aGVHD) model, IL-2/mAb complexes given for only 4 days resulted in rapid mortality, indicating IL-2/mAb complexes can drive conventional T-cell (Tcon)-mediated injury. In contrast, Treg infusions, which uniformly suppress aGVHD, increased Treg frequency and were effective in preventing the onset of, and treating, established cGVHD. Efficacy was dependent upon CXCR5-sufficient Tregs homing to, and inhibiting, GC reactions. These studies indicate that the infusion of Tregs, especially ones enriched for GC homing, may be desirable for cGVHD therapy. Although IL-2/mAb complexes can be efficacious in cGVHD, a cautious approach needs to be taken in settings in which aGVHD elements, and associated Tcon, are present. PMID:27385791

Transforming growth factor beta induced FoxP3+ regulatory T cells suppress Th1 mediated experimental colitis.

PubMed

Fantini, M C; Becker, C; Tubbe, I; Nikolaev, A; Lehr, H A; Galle, P; Neurath, M F

2006-05-01

The imbalance between effector and regulatory T cells plays a central role in the pathogenesis of inflammatory bowel diseases. In addition to the thymus, CD4+CD25+ regulatory T cells can be induced in the periphery from a population of CD25- T cells by treatment with transforming growth factor beta (TGF-beta). Here, we analysed the in vivo function of TGF-beta induced regulatory T (Ti-Treg) cells in experimental colitis. Ti-Treg cells were generated in cell culture in the presence or absence of TGF-beta and tested for their regulatory potential in experimental colitis using the CD4+CD62L+ T cell transfer model. Ti-Treg cells significantly suppressed Th1 mediated colitis on CD4+CD62L+ T cell transfer in vivo, as shown by high resolution endoscopy, histology, immunohistochemistry, and cytokine analysis. Further analysis of in vivo and in vitro expanded Ti-Treg cells showed that exogenous interleukin 2 (IL-2) was crucial for survival and expansion of these cells. Our data suggest that regulatory Ti-Treg cells expand by TGF-beta and exogenous IL-2 derived from effector T cells at the site of inflammation. In addition to Tr1 and thymic CD4+CD25+ T cells, peripheral Ti-Treg cells emerge as a class of regulatory T cells with therapeutic potential in T cell mediated chronic intestinal inflammation.

Early, but not late, treatment with human umbilical cord blood-derived mesenchymal stem cells attenuates cisplatin nephrotoxicity through immunomodulation.

PubMed

Park, Ji Hyeon; Jang, Hye Ryoun; Kim, Do Hee; Kwon, Ghee Young; Lee, Jung Eun; Huh, Wooseong; Choi, Soo Jin; Oh, Wonil; Oh, Ha Young; Kim, Yoon-Goo

2017-10-01

Preemptive treatment with mesenchymal stem cells (MSCs) can attenuate cisplatin-induced acute kidney injury (AKI). However, it is uncertain whether MSC treatment after the development of renal dysfunction prevents AKI progression or if MSC immunomodulatory properties contribute to MSC therapy. In this study, human umbilical cord blood (hUCB)-derived MSCs were used to compare the effects and mechanisms of early and late MSC therapy in a murine model. After cisplatin injection into C57BL/6 mice, hUCB-MSCs were administered on day 1 (early treatment) or day 3 (late treatment). With early treatment, cisplatin nephrotoxicity was attenuated as evidenced by decreased blood urea nitrogen (BUN) and reduced apoptosis and tubular injury scores on day 3 Early treatment resulted in downregulation of intrarenal monocyte chemotactic protein-1 and IL-6 expression and upregulation of IL-10 and VEGF expression. Flow cytometric analysis showed similar populations of infiltrated immune cells in both groups; however, regulatory T-cell (Treg) infiltration was 2.5-fold higher in the early treatment group. The role of Tregs was confirmed by the blunted effect of early treatment on renal injury after Treg depletion. In contrast, late treatment (at a time when BUN levels were 2-fold higher than baseline levels) showed no renoprotective effects on day 6 Neither the populations of intrarenal infiltrating immune cells (including Tregs) nor cytokine expression levels were affected by late treatment. Our results suggest that early MSC treatment attenuates renal injury by Treg induction and immunomodulation, whereas a late treatment (i.e., after the development of renal dysfunction) does not prevent AKI progression or alter the intrarenal inflammatory micromilieu. Copyright © 2017 the American Physiological Society.

In Vivo Expansion of Activated Foxp3+ Regulatory T Cells and Establishment of a Type 2 Immune Response upon IL-33 Treatment Protect against Experimental Arthritis.

PubMed

Biton, Jérôme; Khaleghparast Athari, Sara; Thiolat, Allan; Santinon, François; Lemeiter, Delphine; Hervé, Roxane; Delavallée, Laure; Levescot, Anais; Roga, Stéphane; Decker, Patrice; Girard, Jean-Philippe; Herbelin, André; Boissier, Marie-Christophe; Bessis, Natacha

2016-09-01

IL-33 is strongly involved in several inflammatory and autoimmune disorders with both pro- and anti-inflammatory properties. However, its contribution to chronic autoimmune inflammation, such as rheumatoid arthritis, is ill defined and probably requires tight regulation. In this study, we aimed at deciphering the complex role of IL-33 in a model of rheumatoid arthritis, namely, collagen-induced arthritis (CIA). We report that repeated injections of IL-33 during induction (early) and during development (late) of CIA strongly suppressed clinical and histological signs of arthritis. In contrast, a late IL-33 injection had no effect. The cellular mechanism involved in protection was related to an enhanced type 2 immune response, including the expansion of eosinophils, Th2 cells, and type 2 innate lymphoid cells, associated with an increase in type 2 cytokine levels in the serum of IL-33-treated mice. Moreover, our work strongly highlights the interplay between IL-33 and regulatory T cells (Tregs), demonstrated by the dramatic in vivo increase in Treg frequencies after IL-33 treatment of CIA. More importantly, Tregs from IL-33-treated mice displayed enhanced capacities to suppress IFN-γ production by effector T cells, suggesting that IL-33 not only favors Treg proliferation but also enhances their immunosuppressive properties. In concordance with these observations, we found that IL-33 induced the emergence of a CD39(high) Treg population in a ST2L-dependent manner. Our findings reveal a powerful anti-inflammatory mechanism by which IL-33 administration inhibits arthritis development. Copyright © 2016 by The American Association of Immunologists, Inc.

Regulatory T cells protect mice against coxsackievirus-induced myocarditis through the transforming growth factor beta-coxsackie-adenovirus receptor pathway.

PubMed

Shi, Yu; Fukuoka, Masahiro; Li, Guohua; Liu, Youan; Chen, Manyin; Konviser, Michael; Chen, Xin; Opavsky, Mary Anne; Liu, Peter P

2010-06-22

Coxsackievirus B3 infection is an excellent model of human myocarditis and dilated cardiomyopathy. Cardiac injury is caused either by a direct cytopathic effect of the virus or through immune-mediated mechanisms. Regulatory T cells (Tregs) play an important role in the negative modulation of host immune responses and set the threshold of autoimmune activation. This study was designed to test the protective effects of Tregs and to determine the underlying mechanisms. Carboxyfluorescein diacetate succinimidyl ester-labeled Tregs or naïve CD4(+) T cells were injected intravenously once every 2 weeks 3 times into mice. The mice were then challenged with intraperitoneal coxsackievirus B3 immediately after the last cell transfer. Transfer of Tregs showed higher survival rates than transfer of CD4(+) T cells (P=0.0136) but not compared with the PBS injection group (P=0.0589). Interestingly, Tregs also significantly decreased virus titers and inflammatory scores in the heart. Transforming growth factor-beta and phosphorylated AKT were upregulated in Tregs-transferred mice and coxsackie-adenovirus receptor expression was decreased in the heart compared with control groups. Transforming growth factor-beta decreased coxsackie-adenovirus receptor expression and inhibited coxsackievirus B3 infection in HL-1 cells and neonatal cardiac myocytes. Splenocytes collected from Treg-, CD4(+) T-cell-, and PBS-treated mice proliferated equally when stimulated with heat-inactivated virus, whereas in the Treg group, the proliferation rate was reduced significantly when stimulated with noninfected heart tissue homogenate. Adoptive transfer of Tregs protected mice from coxsackievirus B3-induced myocarditis through the transforming growth factor beta-coxsackie-adenovirus receptor pathway and thus suppresses the immune response to cardiac tissue, maintaining the antiviral immune response.

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

PubMed

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.

Relationship of Th17/Treg Cells and Radiation Pneumonia in Locally Advanced Esophageal Carcinoma.

PubMed

Wang, Yan; Xu, Gang; Wang, Jie; Li, Xin-Hua; Sun, Ping; Zhang, Wei; Li, Jun-Xia; Wu, Chao-Yang

2017-08-01

Radiation pneumonia is a main side-effect that has limited the clinical usage of radiotherapy in locally advanced esophageal carcinoma. T helper cells 17 (Th 17) and T regulatory cells (Tregs) play an important role in inflammatory diseases. The balance between Treg and Th17 cells is a key factor in the progression of many inflammatory and autoimmune diseases. Whether Tregs and Th17 cells are predictive factors of radiation pneumonia has not yet been reported. In this study, we investigated the relationships of Treg/Th17 cells and radiation pneumonia in patients with locally advanced esophageal cancer who received radiotherapy. One hundred and forty-eight patients with locally advanced esophageal cancer who received radical and palliative radiotherapy were enrolled. The levels of Th17 and Treg cells in the blood of patients were detected using flow cytometry at the time point of pre-radiotherapy, 1st, 2nd, 3rd, 4th, 5th and 6th week from the start of radiation and 4 weeks after completion of radiotherapy. Radiation pneumonia was evaluated according to Radiation Therapy Oncology Group's acute radiation pneumonia standards, with the endpoint being grade 2 or above radiation pneumonia. There were 24 cases of radiation pneumonia in 148 cases of locally advanced esophageal cancer patients who underwent radiotherapy. Th17 cells increased and, in contrast, Treg cells decreased in the radiation pneumonia group. The change in the ratio of Th17/Treg was more pronounced and the difference was statistically significant from the 5th week after irradiation compared to patients with no radiation pneumonia (p<0.05). There was no significant difference in dosimetric parameters, including V5, V20, V30 and mean lung dose (MLD) and clinical factors, such as gender, age, smoking history, history of surgery and chemotherapy. The ratio of Th17/Treg cells may be an effective predictive factor of radiation pneumonia. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Atopic dermatitis induces the expansion of thymus-derived regulatory T cells exhibiting a Th2-like phenotype in mice.

PubMed

Moosbrugger-Martinz, Verena; Tripp, Christoph H; Clausen, Björn E; Schmuth, Matthias; Dubrac, Sandrine

2016-05-01

Atopic dermatitis (AD) is a widespread inflammatory skin disease with an early onset, characterized by pruritus, eczematous lesions and skin dryness. This chronic relapsing disease is believed to be primarily a result of a defective epidermal barrier function associated with genetic susceptibility, immune hyper-responsiveness of the skin and environmental factors. Although the important role of abnormal immune reactivity in the pathogenesis of AD is widely accepted, the role of regulatory T cells (Tregs) remains elusive. We found that the Treg population is expanded in a mouse model of AD, i.e. mice topically treated with vitamin D3 (VitD). Moreover, mice with AD-like symptoms exhibit increased inducible T-cell costimulator (ICOS)-, cytotoxic T-lymphocyte antigen-4 (CTLA-4)- and Glycoprotein-A repetitions predominant receptor (GARP)-expressing Tregs in skin-draining lymph nodes. Importantly, the differentiation of Tregs into thymus-derived Tregs is favoured in our mouse model of AD. Emigrated skin-derived dendritic cells are required for Treg induction and Langerhans cells are responsible for the biased expansion of thymus-derived Tregs . Intriguingly, thymus-derived Tregs isolated from mice with AD-like symptoms exhibit a Th2 cytokine profile. Thus, AD might favour the expansion of pathogenic Tregs able to produce Th2 cytokines and to promote the disease instead of alleviating symptoms. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Radiation Enhances Regulatory T Cell Representation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kachikwu, Evelyn L.; Iwamoto, Keisuke S.; Liao, Yu-Pei

2011-11-15

Purpose: Immunotherapy could be a useful adjunct to standard cytotoxic therapies such as radiation in patients with micrometastatic disease, although successful integration of immunotherapy into treatment protocols will require further understanding of how standard therapies affect the generation of antitumor immune responses. This study was undertaken to evaluate the impact of radiation therapy (RT) on immunosuppressive T regulatory (Treg) cells. Methods and Materials: Treg cells were identified as a CD4{sup +}CD25{sup hi}Foxp3{sup +} lymphocyte subset, and their fate was followed in a murine TRAMP C1 model of prostate cancer in mice with and without RT. Results: CD4{sup +}CD25{sup hi}Foxp3{sup +}more » Treg cells increased in immune organs after local leg or whole-body radiation. A large part, but not all, of this increase after leg-only irradiation could be ascribed to radiation scatter and Treg cells being intrinsically more radiation resistant than other lymphocyte subpopulations, resulting in their selection. Their functional activity on a per-cell basis was not affected by radiation exposure. Similar findings were made with mice receiving local RT to murine prostate tumors growing in the leg. The importance of the Treg cell population in the response to RT was shown by systemic elimination of Treg cells, which greatly enhanced radiation-induced tumor regression. Conclusions: We conclude that Treg cells are more resistant to radiation than other lymphocytes, resulting in their preferential increase. Treg cells may form an important homeostatic mechanism for tissues injured by radiation, and in a tumor context, they may assist in immune evasion during therapy. Targeting this population may allow enhancement of radiotherapeutic benefit through immune modulation.« less

Association between discordant immunological response to highly active anti-retroviral therapy, regulatory T cell percentage, immune cell activation and very low-level viraemia in HIV-infected patients

PubMed Central

Saison, J; Ferry, T; Demaret, J; Maucort Boulch, D; Venet, F; Perpoint, T; Ader, F; Icard, V; Chidiac, C; Monneret, G

2014-01-01

The mechanisms sustaining the absence of complete immune recovery in HIV-infected patients upon long-term effective highly active anti-retroviral therapy (HAART) remain elusive. Immune activation, regulatory T cells (Tregs) or very low-level viraemia (VLLV) have been alternatively suspected, but rarely investigated simultaneously. We performed a cross-sectional study in HIV-infected aviraemic subjects (mean duration of HAART: 12 years) to concomitantly assess parameters associated independently with inadequate immunological response. Patients were classified as complete immunological responders (cIR, n = 48) and inadequate immunological responders (iIR, n = 39), depending on the CD4+ T cell count (> or < 500/mm3). Clinical and virological data (including very low-level viraemia) were collected. In parallel, immunophenotyping of CD4+ lymphocytes, including Treg subsets, and CD8+ T cells was performed. Percentages of activated CD4+ T cells, Tregs, effector Tregs and terminal effector Tregs were found to be significantly elevated in iIR. Neither the percentage of activated CD8+ T cells nor VLLV were found to be associated with iIR. In the multivariate analysis, nadir of CD4+ T cell count and percentage of Tregs were the only two parameters associated independently with iIR [odds ratio (OR) = 2·339, P = 0·001, and OR = 0·803, P = 0·041]. We present here the largest study investigating simultaneously the immune response to long-term HAART, activation of CD4+ and CD8+ T cells, Treg percentages and very low-level viraemia. Causative interactions between Tregs and CD4+ T cells should now be explored prospectively in a large patients cohort. PMID:24460818

Staphylococcal enterotoxin A-activated regulatory T cells promote allergen-specific TH2 response to intratracheal allergen inoculation.

PubMed

Zeng, Wei-Ping; McFarland, Margaret M; Zhou, Baohua; Holtfreter, Silva; Flesher, Susan; Cheung, Ambrose; Mallick, Avishek

2017-02-01

T H 2 responses are implicated in asthma pathobiology. Epidemiologic studies have found a positive association between asthma and exposure to staphylococcal enterotoxins. We used a mouse model of asthma to determine whether staphylococcal enterotoxins promote T H 2 differentiation of allergen-specific CD4 conventional T (Tcon) cells and asthma by activating allergen-nonspecific regulatory T (Treg) cells to create a T H 2-polarizing cytokine milieu. Ovalbumin (OVA)-specific, staphylococcal enterotoxin A (SEA)-nonreactive naive CD4 Tcon cells were cocultured with SEA-reactive allergen-nonspecific Treg or CD4 Tcon cells in the presence of OVA and SEA. The OVA-specific CD4 T cells were then analyzed for IL-13 and IFN-γ expression. SEA-activated Treg cells were analyzed for the expression of the T H 2-polarizing cytokine IL-4 and the T-cell activation markers CD69 and CD62L. For asthma induction, mice were intratracheally sensitized with OVA or cat dander extract (CDE) alone or together with SEA and then challenged with OVA or CDE. Mice were also subject to transient Treg cell depletion before sensitization with OVA plus SEA. Asthma features and T H 2 differentiation in these mice were analyzed. SEA-activated Treg cells induced IL-13 but suppressed IFN-γ expression in OVA-specific CD4 Tcon cells. SEA-activated Treg cells expressed IL-4, upregulated CD69, and downregulated CD62L. Sensitization with OVA plus SEA but not OVA alone induced asthma, and SEA exacerbated asthma induced by CDE. Depletion of Treg cells abolished these effects of SEA and IL-13 expression in OVA-specific T cells. SEA promoted T H 2 responses of allergen-specific T cells and asthma pathogenesis by activating Treg cells. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Sequential monitoring and stability of ex vivo-expanded autologous and non-autologous regulatory T cells following infusion in non-human primates

PubMed Central

Zhang, H.; Guo, H.; Lu, L.; Zahorchak, A. F.; Wiseman, R. W.; Raimondi, G.; Cooper, D. K. C.; Ezzelarab, M. B.; Thomson, A. W.

2016-01-01

Ex vivo-expanded cynomolgus monkey CD4+CD25+CD127− regulatory T cells (Treg) maintained Foxp3 demethylation status at the Treg-Specific Demethylation Region (TSDR), and potently suppressed T cell proliferation through 3 rounds of expansion. When CFSE- or VPD450-labeled autologous (auto) and non-autologous (non-auto) expanded Treg were infused into monkeys, the number of labeled auto-Treg in peripheral blood declined rapidly during the first week, but persisted at low levels in both normal and anti-thymocyte globulin plus rapamycin-treated (immunosuppressed; IS) animals for at least 3 weeks. By contrast, MHC-mismatched non-auto-Treg could not be detected in normal monkey blood or in blood of two out of the three IS monkeys by day 6 post-infusion. They were also more difficult to detect than auto-Treg in peripheral lymphoid tissue. Both auto- and non-auto-Treg maintained Ki67 expression early after infusion. Sequential monitoring revealed that adoptively-transferred auto-Treg maintained similarly high levels of Foxp3 and CD25 and low CD127 compared with endogenous Treg, although Foxp3 staining diminished over time in these non-transplanted recipients. Thus, infused ex vivo-expanded auto-Treg persist longer than MHC-mismatched non-auto-Treg in blood of non-human primates and can be detected in secondary lymphoid tissue. Host lymphodepletion and rapamycin administration did not consistently prolong the persistence of non-auto-Treg in these sites. PMID:25783759

Emerging Functions of Regulatory T Cells in Tissue Homeostasis

PubMed Central

Sharma, Amit; Rudra, Dipayan

2018-01-01

CD4+Foxp3+ regulatory T-cells (Tregs) are a unique subset of helper T-cells, which regulate immune response and establish peripheral tolerance. Tregs not only maintain the tone and tenor of an immune response by dominant tolerance but, in recent years, have also been identified as key players in resolving tissue inflammation and as mediators of tissue healing. Apart from being diverse in their origin (thymic and peripheral) and location (lymphoid and tissue resident), Tregs are also phenotypically heterogeneous as per the orientation of ongoing immune response. In this review, we discuss the recent advances in the field of Treg biology in general, and non-lymphoid and tissue-resident Tregs in particular. We elaborate upon well-known visceral adipose tissue, colon, skin, and tumor-infiltrating Tregs and newly identified tissue Treg populations as in lungs, skeletal muscle, placenta, and other tissues. Our attempt is to differentiate Tregs based on distinctive properties of their location, origin, ligand specificity, chemotaxis, and specific suppressive mechanisms. Despite ever expanding roles in maintaining systemic homeostasis, Tregs are employed by large varieties of tumors to dampen antitumor immunity. Thus, a comprehensive understanding of Treg biology in the context of inflammation can be instrumental in effectively managing tissue transplantation, autoimmunity, and antitumor immune responses. PMID:29887862

Knockdown of HMGB1 in tumor cells attenuates their ability to induce regulatory T cells and uncovers naturally acquired CD8 T cell-dependent antitumor immunity.

PubMed

Liu, Zuqiang; Falo, Louis D; You, Zhaoyang

2011-07-01

Although high mobility group box 1 (HMGB1) in tumor cells is involved in many aspects of tumor progression, its role in tumor immune suppression remains elusive. Host cell-derived IL-10 suppressed a naturally acquired CD8 T cell-dependent antitumor response. The suppressive activity of tumor-associated Foxp3(+)CD4(+)CD25(+) regulatory T cells (Treg) was IL-10 dependent. Neutralizing HMGB1 impaired tumor cell-promoted IL-10 production by Treg. Short hairpin RNA-mediated knockdown of HMGB1 (HMGB1 KD) in tumor cells did not affect tumor cell growth but uncovered naturally acquired long-lasting tumor-specific IFN-γ- or TNF-α-producing CD8 T cell responses and attenuated their ability to induce Treg, leading to naturally acquired CD8 T cell- or IFN-γ-dependent tumor rejection. The data suggest that tumor cell-derived HMGB1 may suppress naturally acquired CD8 T cell-dependent antitumor immunity via enhancing Treg to produce IL-10, which is necessary for Treg-mediated immune suppression.

GM-CSF-Induced Regulatory T cells Selectively Inhibit Anti-Acetylcholine Receptor-Specific Immune Responses in Experimental Myasthenia Gravis

PubMed Central

Sheng, Jian Rong; Muthusamy, Thiruppathi; Prabahakar, Bellur S.; Meriggioli, Matthew N.

2011-01-01

We and others have demonstrated the ability of granulocyte-macrophage colony-stimulating factor (GM-CSF) to suppress autoimmunity by increasing the number of CD4+CD25+ regulatory T cells (Tregs). In the current study, we have explored the critical role of induced antigen specific Tregs in the therapeutic effects of GM-CSF in murine experimental autoimmune myasthenia gravis (EAMG). Specifically, we show that Tregs from GM-CSF treated EAMG mice (GM-CSF/AChR-induced-Tregs) adoptively transferred into animals with EAMG suppressed clinical disease more potently than equal numbers of Tregs from either GM-CSF untreated EAMG mice or healthy mice treated with GM-CSF. In addition, GM-CSF/AChR-induced-Tregs selectively suppressed antigen specific T cell proliferation induced by AChR relative to that induced by an irrelevant self antigen, (thyroglobulin) and failed to significantly alter T cell proliferation in response to an exogenous antigen (ovalbumin). These results are consistent with the hypothesized mechanism of action of GM-CSF involving the mobilization of tolerogenic dendritic cell precursors which, upon antigen (AChR) capture, suppress the anti-AChR immune response through the induction/expansion of AChR-specific Tregs. PMID:22099723

A highly relevant and efficient single step method for simultaneous depletion and isolation of human regulatory T cells in a clinical setting.

PubMed

Brezar, Vedran; Ruffin, Nicolas; Lévy, Yves; Seddiki, Nabila

2014-09-01

Regulatory T cells (Tregs) are pivotal in preventing autoimmunity. They play a major but still ambiguous role in cancer and viral infections. Functional studies of human Tregs are often hampered by numerous technical difficulties arising from imperfections in isolating and depleting protocols, together with the usual low cell number available from clinical samples. We standardized a simple procedure (Single Step Method, SSM), based on magnetic beads technology, in which both depletion and isolation of human Tregs with high purities are simultaneously achieved. SSM is suitable when using low cell numbers either fresh or frozen from both patients and healthy individuals. It allows simultaneous Tregs isolation and depletion that can be used for further functional work to monitor suppressive function of isolated Tregs (in vitro suppression assay) and also effector IFN-γ responses of Tregs-depleted cell fraction (OX40 assay). To our knowledge, there is no accurate standardized method for Tregs isolation and depletion in a clinical context. SSM could thus be used and easily standardized across different laboratories. Copyright © 2014 Elsevier B.V. All rights reserved.

IFN-α and CD46 stimulation are associated with active lupus and skew natural T regulatory cell differentiation to type 1 regulatory T (Tr1) cells

PubMed Central

Le Buanec, Hélène; Gougeon, Marie-Lise; Mathian, Alexis; Lebon, Pierre; Dupont, Jean-Michel; Peltre, Gabriel; Hemon, Patrice; Schmid, Michel; Bizzini, Bernard; Künding, Thomas; Burny, Arsène; Bensussan, Armand; Amoura, Zahir; Gallo, Robert C.; Zagury, Daniel

2011-01-01

Immune suppressive activities exerted by regulatory T-cell subsets have several specific functions, including self-tolerance and regulation of adaptive immune reactions, and their dysfunction can lead to autoimmune diseases and contribute to AIDS and cancer. Two functionally distinct regulatory T-cell subsets are currently identified in peripheral tissues: thymus-developed natural T regulatory cells (nTregs) controlling self-tolerance and antiinflammatory IL-10–secreting type 1 regulatory T cells (Tr1) derived from Ag-stimulated T cells, which regulate inflammation-dependent adaptive immunity and minimize immunopathology. We establish herein that cell contact-mediated nTreg regulatory function is inhibited by inflammation, especially in the presence of the complement C3b receptor (CD46). Instead, as with other T-cell subsets, the latter inflammatory conditions of stimulation skew nTreg differentiation to Tr1 cells secreting IL-10, an effect potentiated by IFN-α. The clinical relevance of these findings was verified in a study of 152 lupus patients, in which we showed that lupus nTreg dysfunction is not due to intrinsic defects but is rather induced by C3b stimulation of CD46 and IFN-α and that these immune components of inflammation are directly associated with active lupus. These results provide a rationale for using anti–IFN-α Ab immunotherapy in lupus patients. PMID:22065791

Sodium chloride inhibits the suppressive function of FOXP3+ regulatory T cells.

PubMed

Hernandez, Amanda L; Kitz, Alexandra; Wu, Chuan; Lowther, Daniel E; Rodriguez, Donald M; Vudattu, Nalini; Deng, Songyan; Herold, Kevan C; Kuchroo, Vijay K; Kleinewietfeld, Markus; Hafler, David A

2015-11-02

FOXP3+ Tregs are central for the maintenance of self-tolerance and can be defective in autoimmunity. In multiple sclerosis and type-1 diabetes, dysfunctional self-tolerance is partially mediated by a population of IFNγ-secreting Tregs. It was previously reported that increased NaCl concentrations promote the induction of proinflammatory Th17 cells and that high-salt diets exacerbate experimental models of autoimmunity. Here, we have shown that increasing NaCl, either in vitro or in murine models via diet, markedly impairs Treg function. NaCl increased IFNγ secretion in Tregs, and reducing IFNγ - either by neutralization with anti-IFNγ antibodies or shRNA-mediated knockdown - restored suppressive activity in Tregs. The heightened IFNγ secretion and loss of Treg function were mediated by the serum/glucocorticoid-regulated kinase (SGK1). A high-salt diet also impaired human Treg function and was associated with the induction of IFNγ-secreting Tregs in a xenogeneic graft-versus-host disease model and in adoptive transfer models of experimental colitis. Our results demonstrate a putative role for an environmental factor that promotes autoimmunity by inducing proinflammatory responses in CD4 effector cells and Treg pathways.

Acquisition of T regulatory function in cathepsin L-inhibited T cells by eye-derived CTLA-2alpha during inflammatory conditions.

PubMed

Sugita, Sunao; Horie, Shintaro; Nakamura, Orie; Maruyama, Kazuichi; Takase, Hiroshi; Usui, Yoshihiko; Takeuchi, Masaru; Ishidoh, Kazumi; Koike, Masato; Uchiyama, Yasuo; Peters, Christoph; Yamamoto, Yoshimi; Mochizuki, Manabu

2009-10-15

Pigment epithelium isolated from the eye possesses immunosuppressive properties such as regulatory T (Treg) cell induction; e.g., cultured retinal pigment epithelium (RPE) converts CD4(+) T cells into Treg cells in vitro. RPE constitutively expresses a novel immunosuppressive factor, CTLA-2alpha, which is a cathepsin L (CathL) inhibitor, and this molecule acts via RPE to induce Treg cells. To clarify CTLA-2alpha's role in the T cell response to RPE in ocular inflammation, we used the experimental autoimmune uveitis (EAU) animal model to examine this new immunosuppressive property of RPE. In EAU models, TGF-beta, but not IFN-gamma inflammatory cytokines, promotes the up-regulation of the expression of CTLA-2alpha in RPE. Similarly, CTLA-2alpha via RPE was able to promote TGF-beta production by the CD4(+) T cells. The RPE-exposed T cells (RPE-induced Treg cells) greatly produced TGF-beta and suppressed bystander effector T cells. There was less expression of CathL by the RPE-exposed T cells, and CathL-inhibited T cells were able to acquire the Treg phenotype. Moreover, CathL-deficient mice spontaneously produced Treg cells, with the increase in T cells potentially providing protection against ocular inflammation. More importantly, CD4(+) T cells from EAU in CathL knockout mice or rCTLA-2alpha from EAU animals were found to contain a high population of forkhead box p3(+) T cells. In both EAU models, there was significant suppression of the ocular inflammation. These results indicate that RPE secretes CTLA-2alpha, thereby enabling the bystander T cells to be converted into Treg cells via TGF-beta promotion.

Coexistence of Th1/Th2 and Th17/Treg imbalances in patients with allergic asthma.

PubMed

Shi, Yu-heng; Shi, Guo-chao; Wan, Huan-ying; Jiang, Li-hua; Ai, Xiang-yan; Zhu, Hai-xing; Tang, Wei; Ma, Jia-yun; Jin, Xiao-yan; Zhang, Bo-ying

2011-07-05

Recent recognition is that Th2 response is insufficient to fully explain the aetiology of asthma. Other CD4(+) T cells subsets might play a role in asthma. We investigated the relative abundance and activities of Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells in patients with allergic asthma. Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma and 20 healthy donors were enrolled. All patients were allergic to house dust mites. Plasma total IgE, pulmonary function and Asthma Control Questionnaire were assessed. The proportions of peripheral blood Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells were determined by flow cytometry. The expression of cytokines in plasma and in the culture supernatant of peripheral blood mononuclear cells was determined by enzyme linked, immunosorbent assay. The frequency of blood Th2 cells and IL-4 levels in plasma and culture supernatant of peripheral blood mononuclear cells were increased in all patients with allergic asthma. The frequency of Th17 cells and the plasma and culture supernatant levels of IL-17 were increased, whereas the frequency of CD4(+)CD25(+) Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. Dermatophagoides pteronyssinus specific IgE levels were positively correlated with the percentage of blood Th2 cells and plasma IL-4 levels. Forced expiratory volume in the first second was negatively correlated with the frequency of Th17 cells and plasma IL-17 levels, and positively correlated with the frequency of Treg cells. However, mean Asthma Control Questionnaire scores were positively correlated with the frequency of Th17 cells and plasma IL-17 levels, and negatively correlated with the frequency of Treg cells. Imbalances in Th1/Th2 and Th17/Treg were found in patients with allergic asthma. Furthermore, elevated Th17 cell responses, the absence of Tregs and an imbalance in Th17/Treg levels were associated with moderate to severe asthma.

T(reg) cells may regulate interlukin-17 production by modulating TH1 responses in 1,3-β-glucan-induced lung inflammation in mice.

PubMed

Chen, Ying; Liu, Fangwei; Weng, Dong; Song, Laiyu; Li, Cuiying; Tang, Wen; Yu, Ye; Dai, Wujing; Chen, Jie

2013-01-01

1,3-β-glucan is considered a fungal biomarker and exposure to this agent can induce lung inflammation. Complement activation plays an important role in early immune responses to β-glucan. Previous studies showed that T-regulatory cells (Tregs) regulated 1,3-β-glucan-induced lung inflammation by modulating the maintenance of immune homeostasis in the lung. Both interleukin (IL)-17 and TH17 cells play pivotal roles in inflammation associated with lung disease and share reciprocal developmental pathways with Tregs. However, the effect of Tregs on IL-17 and TH17 responses in 1,3-β-glucan-induced lung inflammation remains unclear. In this study, mice were exposed to 1,3-β-glucan by intratracheal instillation. To investigate the effects of Tregs on IL-17 and TH17 cells in the induced lung inflammation, a Treg-depleted mice model was generated by administration of anti-CD25 mAb. The results indicated that Treg-depleted mice showed more severe pathological inflammatory changes in lung tissues. Tregs depletion reduced IL-17 expression in these tissues, and increased those of TH1 cytokines. The expression of IL-17 increased at the early phase of the inflammation response. There were no significant effects of the Tregs on expression of RORγt and IL-6 or the amount of CD4(+)IL-17(+) cells in the lungs. When taken together, the late phase of the 1,3-β-glucan-induced inflammatory response in the mice was primarily mediated by TH1 cytokines rather than IL-17. In contrast, the early phase of the inflammatory response might be mediated in part by IL-17 along with activated complement. Tregs might be required for IL-17 expression during the late phase inflammatory response in mice. The increased IL-17 mRNA observed during the 1,3-β-glucan induced inflammatory response were attributed to cells other than TH17 cells.

Activation of Salmonella Typhi-specific regulatory T cells in typhoid disease in a wild-type S. Typhi challenge model.

PubMed

McArthur, Monica A; Fresnay, Stephanie; Magder, Laurence S; Darton, Thomas C; Jones, Claire; Waddington, Claire S; Blohmke, Christoph J; Dougan, Gordon; Angus, Brian; Levine, Myron M; Pollard, Andrew J; Sztein, Marcelo B

2015-05-01

Salmonella Typhi (S. Typhi), the causative agent of typhoid fever, causes significant morbidity and mortality worldwide. Currently available vaccines are moderately efficacious, and identification of immunological responses associated with protection or disease will facilitate the development of improved vaccines. We investigated S. Typhi-specific modulation of activation and homing potential of circulating regulatory T cells (Treg) by flow and mass cytometry using specimens obtained from a human challenge study. Peripheral blood mononuclear cells were obtained from volunteers pre- and at multiple time-points post-challenge with wild-type S. Typhi. We identified differing patterns of S. Typhi-specific modulation of the homing potential of circulating Treg between volunteers diagnosed with typhoid (TD) and those who were not (No TD). TD volunteers demonstrated up-regulation of the gut homing molecule integrin α4ß7 pre-challenge, followed by a significant down-regulation post-challenge consistent with Treg homing to the gut. Additionally, S. Typhi-specific Treg from TD volunteers exhibited up-regulation of activation molecules post-challenge (e.g., HLA-DR, LFA-1). We further demonstrate that depletion of Treg results in increased S. Typhi-specific cytokine production by CD8+ TEM in vitro. These results suggest that the tissue distribution of activated Treg, their characteristics and activation status may play a pivotal role in typhoid fever, possibly through suppression of S. Typhi-specific effector T cell responses. These studies provide important novel insights into the regulation of immune responses that are likely to be critical in protection against typhoid and other enteric infectious diseases.

Defective circulating CD25 regulatory T cells in patients with chronic immune thrombocytopenic purpura

PubMed Central

Yu, Jin; Heck, Susanne; Patel, Vivek; Levan, Jared; Yu, Yu; Bussel, James B.

2008-01-01

Immune thrombocytopenic purpura (ITP) is characterized by the presence of antiplatelet autoantibodies as a result of loss of tolerance. CD4+CD25+ regulatory T cells (Tregs) are important for maintenance of peripheral tolerance. Decreased levels of peripheral Tregs in patients with ITP have been reported. To test whether inefficient production or reduced immunosuppressive activity of Tregs contributes to loss of tolerance in patients with chronic ITP, we investigated the frequency and function of their circulating CD4+CD25hi Tregs. We found a com-parable frequency of circulating CD4+CD25hiFoxp3+ Tregs in patients and controls (n = 16, P > .05). However, sorted CD4+CD25hi cells from patients with chronic ITP (n = 13) had a 2-fold reduction of in vitro immunosuppressive activity compared with controls (n = 10, P < .05). The impaired suppression was specific to Tregs as shown by cross-mixing experiments with T cells from controls. These data suggest that functional defects in Tregs contribute to breakdown of self-tolerance in patients with chronic ITP. PMID:18420827

The kinase DYRK1A reciprocally regulates the differentiation of Th17 and regulatory T cells

PubMed Central

Khor, Bernard; Gagnon, John D; Goel, Gautam; Roche, Marly I; Conway, Kara L; Tran, Khoa; Aldrich, Leslie N; Sundberg, Thomas B; Paterson, Alison M; Mordecai, Scott; Dombkowski, David; Schirmer, Melanie; Tan, Pauline H; Bhan, Atul K; Roychoudhuri, Rahul; Restifo, Nicholas P; O'Shea, John J; Medoff, Benjamin D; Shamji, Alykhan F; Schreiber, Stuart L; Sharpe, Arlene H; Shaw, Stanley Y; Xavier, Ramnik J

2015-01-01

The balance between Th17 and T regulatory (Treg) cells critically modulates immune homeostasis, with an inadequate Treg response contributing to inflammatory disease. Using an unbiased chemical biology approach, we identified a novel role for the dual specificity tyrosine-phosphorylation-regulated kinase DYRK1A in regulating this balance. Inhibition of DYRK1A enhances Treg differentiation and impairs Th17 differentiation without affecting known pathways of Treg/Th17 differentiation. Thus, DYRK1A represents a novel mechanistic node at the branch point between commitment to either Treg or Th17 lineages. Importantly, both Treg cells generated using the DYRK1A inhibitor harmine and direct administration of harmine itself potently attenuate inflammation in multiple experimental models of systemic autoimmunity and mucosal inflammation. Our results identify DYRK1A as a physiologically relevant regulator of Treg cell differentiation and suggest a broader role for other DYRK family members in immune homeostasis. These results are discussed in the context of human diseases associated with dysregulated DYRK activity. DOI: http://dx.doi.org/10.7554/eLife.05920.001 PMID:25998054

Tumor-secreted miR-214 induces regulatory T cells: a major link between immune evasion and tumor growth

PubMed Central

Yin, Yuan; Cai, Xing; Chen, Xi; Liang, Hongwei; Zhang, Yujing; Li, Jing; Wang, Zuoyun; Chen, Xiulan; Zhang, Wen; Yokoyama, Seiji; Wang, Cheng; Li, Liang; Li, Limin; Hou, Dongxia; Dong, Lei; Xu, Tao; Hiroi, Takachika; Yang, Fuquan; Ji, Hongbin; Zhang, Junfeng; Zen, Ke; Zhang, Chen-Yu

2014-01-01

An increased population of CD4+CD25highFoxp3+ regulatory T cells (Tregs) in the tumor-associated microenvironment plays an important role in cancer immune evasion. However, the underlying mechanism remains unclear. Here we observed an increased secretion of miR-214 in various types of human cancers and mouse tumor models. Tumor-secreted miR-214 was sufficiently delivered into recipient T cells by microvesicles (MVs). In targeted mouse peripheral CD4+ T cells, tumor-derived miR-214 efficiently downregulated phosphatase and tensin homolog (PTEN) and promoted Treg expansion. The miR-214-induced Tregs secreted higher levels of IL-10 and promoted tumor growth in nude mice. Furthermore, in vivo studies indicated that Treg expansion mediated by cancer cell-secreted miR-214 resulted in enhanced immune suppression and tumor implantation/growth in mice. The MV delivery of anti-miR-214 antisense oligonucleotides (ASOs) into mice implanted with tumors blocked Treg expansion and tumor growth. Our study reveals a novel mechanism through which cancer cell actively manipulates immune response via promoting Treg expansion. PMID:25223704

Peripheral Dendritic Cells and CD4+CD25+Foxp3+ Regulatory T Cells in the First Trimester of Normal Pregnancy and in Women with Recurrent Miscarriage

PubMed Central

Kwiatek, Maciej; Gęca, Tomasz; Krzyżanowski, Arkadiusz; Malec, Agnieszka; Kwaśniewska, Anna

2015-01-01

The development of pregnancy is possible due to initiation of immune response in the body of the mother resulting in immune tolerance. Miscarriage may be caused by the impaired maternal immune response to paternal alloantigens located on the surface of trophoblast and fetal cells. The aim of the study was to compare the population of circulating dendritic cells (DCs) and CD4+CD25+Foxp3+ regulatory T cells (TREGs) in the first trimester of a normal pregnancy and in women with recurrent miscarriage and an attempt to determine the relationship between these cells and the role they may play in human reproductive failures. The study was conducted in a group of 33 first trimester pregnant women with recurrent miscarriage and in a group of 20 healthy pregnant women in the first trimester of normal pregnancy. Among mononuclear cells isolated from peripheral blood, the populations of DCs and TREGs were assessed by flow cytometry. The percentage of myeloid DCs and lymphoid DCs showed no significant difference between study and control group. Older maternal age and obesity significantly reduced the pool of circulating myeloid and lymphoid DCs (R=-0.39, p=0.02). In miscarriages the percentage of circulating TREGs was significantly lower compared to normal pregnancies (p=0.003). Among the analysed factors the percentage of TREGs was the most sensitive and the most specific parameter which correlated with the pregnancy loss. The reduction in the population of circulating TREGs suggests immunoregulatory mechanisms disorder in a pregnancy complicated by miscarriage. PMID:25945787

PLAU inferred from a correlation network is critical for suppressor function of regulatory T cells

PubMed Central

He, Feng; Chen, Hairong; Probst-Kepper, Michael; Geffers, Robert; Eifes, Serge; del Sol, Antonio; Schughart, Klaus; Zeng, An-Ping; Balling, Rudi

2012-01-01

Human FOXP3+CD25+CD4+ regulatory T cells (Tregs) are essential to the maintenance of immune homeostasis. Several genes are known to be important for murine Tregs, but for human Tregs the genes and underlying molecular networks controlling the suppressor function still largely remain unclear. Here, we describe a strategy to identify the key genes directly from an undirected correlation network which we reconstruct from a very high time-resolution (HTR) transcriptome during the activation of human Tregs/CD4+ T-effector cells. We show that a predicted top-ranked new key gene PLAU (the plasminogen activator urokinase) is important for the suppressor function of both human and murine Tregs. Further analysis unveils that PLAU is particularly important for memory Tregs and that PLAU mediates Treg suppressor function via STAT5 and ERK signaling pathways. Our study demonstrates the potential for identifying novel key genes for complex dynamic biological processes using a network strategy based on HTR data, and reveals a critical role for PLAU in Treg suppressor function. PMID:23169000

T Cell Receptor Signaling in the Control of Regulatory T Cell Differentiation and Function

PubMed Central

Li, Ming O.; Rudensky, Alexander Y.

2016-01-01

Regulatory T cells (TReg cells), a specialized T cell lineage, have a pivotal function in the control of self-tolerance and inflammatory responses. Recent studies have revealed a discrete mode of TCR signaling that regulates Treg cell differentiation, maintenance and function and that impacts on gene expression, metabolism, cell adhesion and migration of these cells. Here, we discuss the emerging understanding of TCR-guided differentiation of Treg cells in the context of their function in health and disease. PMID:27026074

Detection and significance of TregFoxP3+ and Th17 cells in peripheral blood of non-small cell lung cancer patients

PubMed Central

Li, Sha; Li, Yan; Qu, Xun; Liu, Xiaolin

2014-01-01

Introduction The aim of this study was to explore the relationships between TregFoxP3+ cells and Th17 cells and occurrence of lung cancer. Material and methods The proportions of TregFoxP3+ and Th17 cells, the expression of FoxP3 and RORγt mRNA, and the levels of related cell factors such as transforming growth factor-β (TGF-β), interleukin IL-17 (IL-17) and IL-23 were determined respectively by flow cytometry analysis, real-time-polymerase chain reaction (PCR), and ELISA in peripheral blood of 18 healthy people and 26 patients with non-small cell lung cancer (NSCLC). Results The levels of TregFoxP3+ and Th17, expression of FoxP3 and RORγt mRNA, and ratios of TregFoxP3+/Th17 and FoxP3/RORγt in peripheral blood with NSCLC were higher than those in healthy controls (p < 0.05). The proportion of Th17 cells from NSCLC patients was positively correlated with that of TregFoxP3+ (r = 0.81, p < 0.05). The receiver-operating characteristic (ROC) curve demonstrates that the increased level of TregFoxP3+/Th17 in the peripheral blood may be a useful indicator in early diagnosis of non-small cell lung carcinoma. The TregFoxP3+/Th17 and FoxP3/RORγt levels for patients in stage IV were higher than those of patients in stages I, II, and III (p < 0.05). The levels of TGF-β, IL-17, and IL-23 were higher in NSCLC patients than those in healthy controls. Conclusions The results suggest that ratios of Treg/Th17 correlate with the stage of NSCLC. PMID:24904654

Differential effects of Denileukin Diftitox IL-2 immunotoxin on NK and regulatory T cells in non-human primates

PubMed Central

Yamada, Yohei; Aoyama, Akihiro; Tocco, Georges; Boskovic, Svjetlan; Nadazdin, Ognjenka; Alessandrini, Alessandro; Madsen, Joren C.; Cosimi, A. Benedict; Benichou, Gilles; Kawai, Tatsuo

2012-01-01

Denileukin Diftitox (DD), a fusion protein comprised of IL-2 and diphtheria toxin was initially expected to enhance anti-tumor immunity by selectively eliminating regulatory T cells (Tregs) displaying the high affinity IL-2R (α-β-γ trimers). While DD has been shown to deplete some Tregs in primates, its effects on NK cells (CD16+CD8+NKG2A+CD3−), which constitutively express the intermediate affinity IL-2R (β-γ dimers) and play a critical role in anti-tumor immunity, are still unknown. To address this question, cynomolgus monkeys were injected intravenously with two different doses of DD (8 or 18 μg/Kg). This treatment resulted in a rapid but short-term reduction in detectable peripheral blood resting Tregs (R-Tregs: CD4+CD45RA+Foxp3+) and a transient increase in the number of activated Tregs (A-Tregs: CD4+CD45RA−Foxp3high) followed by their partial depletion (50–60%). On the other hand, all NK cells were deleted immediately and durably after DD administration. This difference was not due to a higher binding or internalization of DD by NK cells as compared to Tregs. Co-administration of DD with IL-15, which binds to IL-2Rβ-γ, abrogated DD-induced NK cell deletion in vitro and in vivo while it did not affect Tregs elimination. Taken together, these results show that DD exerts a potent cytotoxic effect on NK cells, a phenomenon which might impair its anti-tumoral properties. However, co-administration of IL-15 with DD could alleviate this problem by selectively protecting potentially oncolytic NK cells while allowing the depletion of immunosuppressive regulatory T cells in cancer patients. PMID:22586034

Cigarette Smoke Disturbs the Survival of CD8+ Tc/Tregs Partially through Muscarinic Receptors-Dependent Mechanisms in Chronic Obstructive Pulmonary Disease.

PubMed

Chen, Gang; Zhou, Mei; Chen, Long; Meng, Zhao-Ji; Xiong, Xian-Zhi; Liu, Hong-Ju; Xin, Jian-Bao; Zhang, Jian-Chu

2016-01-01

CD8+ T cells (Cytotoxic T cells, Tc) are known to play a critical role in the pathogenesis of smoking related airway inflammation including chronic obstructive pulmonary disease (COPD). However, how cigarette smoke directly impacts systematic CD8+ T cell and regulatory T cell (Treg) subsets, especially by modulating muscarinic acetylcholine receptors (MRs), has yet to be well elucidated. Circulating CD8+ Tc/Tregs in healthy nonsmokers (n = 15), healthy smokers (n = 15) and COPD patients (n = 18) were evaluated by flow cytometry after incubating with anti-CD3, anti-CD8, anti-CD25, anti-Foxp3 antibodies. Peripheral blood T cells (PBT cells) from healthy nonsmokers were cultured in the presence of cigarette smoke extract (CSE) alone or combined with MRs agonist/antagonist for 5 days. Proliferation and apoptosis were evaluated by flow cytometry using Ki-67/Annexin-V antibodies to measure the effects of CSE on the survival of CD8+ Tc/Tregs. While COPD patients have elevated circulating percentage of CD8+ T cells, healthy smokers have higher frequency of CD8+ Tregs. Elevated percentages of CD8+ T cells correlated inversely with declined FEV1 in COPD. CSE promoted the proliferation and inhibited the apoptosis of CD8+ T cells, while facilitated both the proliferation and apoptosis of CD8+ Tregs. Notably, the effects of CSE on CD8+ Tc/Tregs can be mostly simulated or attenuated by muscarine and atropine, the MR agonist and antagonist, respectively. However, neither muscarine nor atropine influenced the apoptosis of CD8+ Tregs. The results imply that cigarette smoking likely facilitates a proinflammatory state in smokers, which is partially mediated by MR dysfunction. The MR antagonist may be a beneficial drug candidate for cigarette smoke-induced chronic airway inflammation.

The Dynamics of Treg/Th17 and the Imbalance of Treg/Th17 in Clonorchis sinensis-Infected Mice

PubMed Central

Hua, Hui; Li, Bo; Zhang, Bo; Yu, Qian; Li, Xiang-Yang; Liu, Ying; Pan, Wei; Liu, Xiang-Ye; Tang, Ren-Xian; Zheng, Kui-Yang

2015-01-01

Clonorchiasis, caused by the liver fluke Clonorchis sinensis, is a chronic parasitic infection regulated by T cell subsets. An imbalance of CD4+CD25+ Foxp3+regulatory T (Treg) and interleukin (IL)-17-secreting T cells (Th17) may control inflammation and play an important role in the pathogenesis of immune evasion. In the present study, we assessed the dynamics of Treg/Th17 and determined whether the Treg/Th17 ratio is altered in C. sinensis-infected mice. The results showed that the percentages of splenic Treg cells in CD4+ T cells were suppressed on day 14 post-infection (PI) but increased on day 56 PI, while Th17 cells were increased on day 56 PI compared with normal control (NC) mice. The Treg/Th17 ratio steadily increased from day 28 to day 56 PI. The hepatic levels of their specific transcription factors (Foxp3 for Treg and RORγt for Th17) were increased in C. sinensis-infected mice from day 14 to 56 PI, and significantly higher than those in NC mice. Meanwhile, serum levels of IL-2 and IL-17 were profoundly increased in C. sinensis-infected mice throughout the experiment; while the concentrations of IL-6 and transforming growth factor β1 (TGF-β1) peaked on day 14 PI, but then decreased on day 28 and 56 PI. Our results provide the first evidence of an increased Treg/Th17 ratio in C. sinensis-infected mice, suggesting that a Treg/Th17 imbalance may play a role in disease outcomes of clonorchiasis. PMID:26599407

Regulatory T cells and other lymphocyte subpopulations in patients with melanoma developing interferon-induced thyroiditis during high-dose interferon-α2b treatment.

PubMed

Soldevila, Berta; Alonso, Núria; Martínez-Arconada, Maria J; Granada, Maria L; Boada, Aram; Vallejos, Virginia; Fraile, Manuel; Fernández-Sanmartín, Marco A; Pujol-Borrell, Ricardo; Puig-Domingo, Manel; Sanmartí, Anna; Martínez-Cáceres, Eva M

2013-04-01

One of the side effects of interferon-alpha therapy is interferon-induced thyroiditis (IIT). The role of lymphocyte subpopulations in IIT melanoma patients remains to be defined. Our objective was to assess different peripheral blood lymphocyte subpopulations, mainly regulatory T cells (Tregs), in melanoma patients who developed IIT. From 30 melanoma patients receiving high-dose interferon (HDI)-alpha 2b (IFN-α2b) treatment, those who developed IIT (IIT patients) were selected and compared with patients who did not develop IIT (Co-MM) and healthy controls (Co-H). Peripheral blood mononuclear cells were obtained before treatment (BT), mid-treatment (MT), end of treatment (ET), 24 weeks post-treatment and at appearance of IIT (TT). Nine patients developed IIT (30%): four Hashimoto's thyroiditis and five destructive thyroiditis. An increase in Tregs was observed in both melanoma groups during HDI treatment. A decrease in CD3(+) , NKT lymphocyte subpopulations and Bcl2 expression on B cells was also observed in both groups. However, no changes were observed in the percentage of CD4(+) , CD8(+) , CD3(+) γδ(+) , CD19(+) , transitional B cells (CD24(high) CD38(high) CD19(+) CD27(-) ), natural killer (NK), invariant NKT (iNKT) lymphocytes and Th1/Th2 balance when BT was compared with ET. At TT, IIT patients had a higher Tregs percentage than Co-MM (P = 0·012) and Co-H (P = 0·004), a higher iNKT percentage than Co-MM (P = 0·011), a higher transitional B cells percentage than Co-H (P = 0·015), a lower CD3(+) percentage than Co-H (P = 0·001) and a lower Bcl2 expression on B cells than Co-H (P < 0·001). Our results point to the immunomodulatory effects of IFN-α on different lymphocyte subpopulations and a possible role of Tregs in melanoma patients who developed IIT. © 2012 Blackwell Publishing Ltd.

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

PubMed

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.

IL-23 Activated γδ T Cells Affect Th17 Cells and Regulatory T Cells by Secreting IL-21 in Children with Primary Nephrotic Syndrome.

PubMed

Zhang, L; Yan, J; Yang, B; Zhang, G; Wang, M; Dong, S; Liu, W; Yang, H; Li, Q

2018-01-01

This study (1) analysed the percentage of γδ T cells, γδ T cell subsets, Th17 cells and regulatory T cells (Treg cells) and (2) determined the role of IL-23 in primary nephrotic syndrome (PNS) patients with active disease and in remission. Eighty-four patients with PNS and 51 healthy age-matched controls were included in this study. The percentage of γδ T cells, γδ T cell subsets, Th17 cells and Treg cells in peripheral blood mononuclear cells (PBMCs) were analysed by fluorescence-activated cell sorting. PMBCs from PNS patients with active disease were cultured in the presence of IL-23, IL-23 and an IL-23 antagonist, or IL23 and an anti-IL-21 monoclonal antibody (mAb). The percentage of γδ T cells, IL-23R + γδ T cells and IL-17 + γδ T cells were significantly increased in PNS patients with active disease. There was a positive correlation between the percentage of γδ T cells, IL-23R + γδ T cells, IL-17 + γδ T cells and the Th17/Treg ratio. IL-23 increased the percentage of γδ T cells and Th17 cells and decreased the percentage of Treg cells in PBMCs isolated from PNS patients with active disease. Anti-IL-21 mAb reduced the percentage of γδ T cells and Th17 cells, but increased the percentage of Treg cells. γδ T cells, IL-17 + γδ T cells and IL-23R + γδ T cells may be involved in the pathogenesis of paediatric PNS by modulating the balance of Th17/Treg cells. γδ T cells may cause an imbalance in Th17/Treg cells by secreting IL-21 in the presence of IL-23. © 2017 The Foundation for the Scandinavian Journal of Immunology.

Immune Privilege and Eye-Derived T-Regulatory Cells.

PubMed

Keino, Hiroshi; Horie, Shintaro; Sugita, Sunao

2018-01-01

Certain cellular components of the eye, such as neural retina, are unable to regenerate and replicate after destructive inflammation. Ocular immune privilege provides the eye with immune protection against intraocular inflammation in order to minimize the risk to vision integrity. The eye and immune system use strategies to maintain the ocular immune privilege by regulating the innate and adaptive immune response, which includes immunological ignorance, peripheral tolerance to eye-derived antigens, and intraocular immunosuppressive microenvironment. In this review, we summarize current knowledge regarding the molecular mechanism responsible for the development and maintenance of ocular immune privilege via regulatory T cells (Tregs), which are generated by the anterior chamber-associated immune deviation (ACAID), and ocular resident cells including corneal endothelial (CE) cells, ocular pigment epithelial (PE) cells, and aqueous humor. Furthermore, we examined the therapeutic potential of Tregs generated by RPE cells that express transforming growth factor beta (TGF- β ), cytotoxic T lymphocyte-associated antigen-2 alpha (CTLA-2 α ), and retinoic acid for autoimmune uveoretinitis and evaluated a new strategy using human RPE-induced Tregs for clinical application in inflammatory ocular disease. We believe that a better understanding of the ocular immune privilege associated with Tregs might offer a new approach with regard to therapeutic interventions for ocular autoimmunity.

Rux largely restores lungs in Iraq PM-exposed mice, Up-regulating regulatory T-cells (Tregs).

PubMed

Lin, David; Li, Jonathan; Razi, Rabail; Qamar, Niha; Levine, Laurie; Zimmerman, Thomas; Hamidi, Sayyed A; Schmidt, Millicent; Golightly, Marc G; Rueb, Todd; Harrington, Andrea; Garnett, Merrill; Antonawich, Frank; McClain, Steven; Miller, Edmund; Cox, Courtney; Huang, Po Hsuan; Szema, Anthony M

2018-05-08

Background Military personnel post-deployment to Iraq and Afghanistan have noted new-onset respiratory illness. This study's primary objective was to further develop an animal model of Iraq Afghanistan War Lung Injury (IAW-LI) and to test a novel class of anti-injury drug called RuX. Methods Particulate Matter (PM) samples were obtained in Iraq then characterized by spectromicroscopy. C57BL/6 mice underwent orotracheal instillation with PM, followed by drinkable treatment with RuX. Lung histology, inspiratory capacity (FlexiVent), thymic/splenic regulatory T cell (Treg) number, and whole-lung genomics were analyzed. Results Tracheal instillation of Iraq PM led to lung septate thickening and lymphocytic inflammation. PM-exposed mice had suppression of thymic/splenic regulatory T-cells (Tregs). Drinking RuX after PM exposure attenuated the histologic lung injury response, improved lung inspiratory capacity, and increased Tregs. Pooled whole lung genomics suggest differences among gene expression of IL-15 among control, PM, and PM + RuX groups. Conclusions RuX, a ruthenium and alpha-lipoic acid complex, attenuates lung injury by improving histology and inspiratory capacity via upregulation of Tregs in Iraq PM-exposed C57BL/6. Plausible genomic effects may involve IL-15 whole lung gene expression.

The Role of Regulatory T Cell in Nontypeable Haemophilus influenzae-Induced Acute Exacerbation of Chronic Obstructive Pulmonary Disease

PubMed Central

Guan, Xuewa; Lu, Yanjiao; Wang, Guoqiang; Fang, Keyong; Wang, Ziyan; Pang, Zhiqiang; Guo, Yingqiao; Lu, Junying; Yuan, Yuze; Ran, Nan

2018-01-01

Chronic obstructive pulmonary disease (COPD) is associated with irreversible persistent airflow limitation and enhanced inflammation. The episodes of acute exacerbation (AECOPD) largely depend on the colonized pathogens such as nontypeable Haemophilus influenzae (NTHi), one of the most commonly isolated bacteria. Regulatory T cells (Tregs) are critical in controlling inflammatory immune responses and maintaining tolerance; however, their role in AECOPD is poorly understood. In this study, we hypothesized a regulatory role of Tregs, as NTHi participated in the progress of COPD. Immunological pathogenesis was investigated in a murine COPD model induced by cigarette smoke (CS). NTHi was administrated through intratracheal instillation for an acute exacerbation. Weight loss and lung function decline were observed in smoke-exposed mice. Mice in experimental groups exhibited serious inflammatory responses via histological and cytokine assessment. Expression levels of Tregs and Th17 cells with specific cytokines TGF-β1 and IL-17 were detected to assess the balance of pro-/anti-inflammatory influence partially. Our findings suggested an anti-inflammatory activity of Tregs in CS-induced model. But this activity was suppressed after NTHi administration. Collectively, these data suggested that NTHi might play a necessary role in downregulating Foxp3 to impair the function of Tregs, helping development into AECOPD. PMID:29725272

Increased numbers of FoxP3-expressing CD4+ CD25+ regulatory T cells in peripheral blood from dogs with atopic dermatitis and its correlation with disease severity.

PubMed

Hauck, Verena; Hügli, Patrick; Meli, Marina L; Rostaher, Ana; Fischer, Nina; Hofmann-Lehmann, Regina; Favrot, Claude

2016-02-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disease of humans and dogs. Regulatory T cells (Tregs) are essential controllers of immune homeostasis and have been shown to play a key role in human AD, even though frequencies of Tregs in atopic human patients vary greatly. Only two studies have reported Treg numbers in the peripheral blood of dogs with canine AD (CAD). This study aimed to assess the numbers of circulating Tregs in healthy and atopic dogs, and to determine whether Treg numbers correlate with age, sex, disease severity or pre-treatment. Client-owned dogs including 14 healthy dogs and 35 dogs with CAD. Expression of Tregs in peripheral blood mononuclear cells was evaluated by flow cytometry. Tregs were phenotypically identified as T cells triple positive for CD4, CD25 and FoxP3. The percentage of circulating CD4(+)  CD25(+)  FoxP3(+) Tregs in atopic dogs was increased significantly compared to healthy dogs (mean 2.1% versus 1%, P = 0.002) and correlated with disease severity (Pruritus Scale: r = 0.48, P = 0.003; CADESI-04: r = 0.34, P = 0.044). No significant differences in age or sex were found in either group and pre-treatment had no influence on results for atopic dogs. Data suggest that, as in humans, CD4(+)  CD25(+)  FoxP3(+) Tregs may contribute to the pathogenesis of CAD as indicated by an association between Treg frequency and disease severity. Further investigation is required to improve the understanding of the role of Tregs in atopic dogs. © 2015 ESVD and ACVD.

Ex vivo expanded natural regulatory T cells from patients with end-stage renal disease or kidney transplantation are useful for autologous cell therapy.

PubMed

Landwehr-Kenzel, Sybille; Zobel, Anne; Hoffmann, Henrike; Landwehr, Niels; Schmueck-Henneresse, Michael; Schachtner, Thomas; Roemhild, Andy; Reinke, Petra

2018-06-01

Novel concepts employing autologous, ex vivo expanded natural regulatory T cells (nTreg) for adoptive transfer has potential to prevent organ rejection after kidney transplantation. However, the impact of dialysis and maintenance immunosuppression on the nTreg phenotype and peripheral survival is not well understood, but essential when assessing patient eligibility. The current study investigates regulatory T-cells in dialysis and kidney transplanted patients and the feasibility of generating a clinically useful nTreg product from these patients. Heparinized blood from 200 individuals including healthy controls, dialysis patients with end stage renal disease and patients 1, 5, 10, 15, 20 years after kidney transplantation were analyzed. Differentiation and maturation of nTregs were studied by flow cytometry in order to compare dialysis patients and kidney transplanted patients under maintenance immunosuppression to healthy controls. CD127 expressing CD4 + CD25 high FoxP3 + nTregs were detectable at increased frequencies in dialysis patients with no negative impact on the nTreg end product quality and therapeutic usefulness of the ex vivo expanded nTregs. Further, despite that immunosuppression mildly altered nTreg maturation, neither dialysis nor pharmacological immunosuppression or previous acute rejection episodes impeded nTreg survival in vivo. Accordingly, the generation of autologous, highly pure nTreg products is feasible and qualifies patients awaiting or having received allogenic kidney transplantation for adoptive nTreg therapy. Thus, our novel treatment approach may enable us to reduce the incidence of organ rejection and reduce the need of long-term immunosuppression. Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

The regulatory T cell effector molecule fibrinogen-like protein 2 is necessary for the development of rapamycin-induced tolerance to fully MHC-mismatched murine cardiac allografts

PubMed Central

Urbanellis, Peter; Shyu, Wendy; Khattar, Ramzi; Wang, Jihong; Zakharova, Anna; He, Wei; Sadozai, Hassan; Amir, Achiya Z; Shalev, Itay; Phillips, M James; Adeyi, Oyedele; Ross, Heather; Grant, David; Levy, Gary A; Chruscinski, Andrzej

2015-01-01

Therapies that promote tolerance in solid organ transplantation will improve patient outcomes by eliminating the need for long-term immunosuppression. To investigate mechanisms of rapamycin-induced tolerance, C3H/HeJ mice were heterotopically transplanted with MHC-mismatched hearts from BALB/cJ mice and were monitored for rejection after a short course of rapamycin treatment. Mice that had received rapamycin developed tolerance with indefinite graft survival, whereas untreated mice all rejected their grafts within 9 days. In vitro, splenic mononuclear cells from tolerant mice maintained primary CD4+ and CD8+ immune responses to donor antigens consistent with a mechanism that involves active suppression of immune responses. Furthermore, infection with lymphocytic choriomeningitis virus strain WE led to loss of tolerance suggesting that tolerance could be overcome by infection. Rapamycin-induced, donor-specific tolerance was associated with an expansion of regulatory T (Treg) cells in both the spleen and allograft and elevated plasma levels of fibrinogen-like protein 2 (FGL2). Depletion of Treg cells with anti-CD25 (PC61) and treatment with anti-FGL2 antibody both prevented tolerance induction. Tolerant allografts were populated with Treg cells that co-expressed FGL2 and FoxP3, whereas rejecting allografts and syngeneic grafts were nearly devoid of dual-staining cells. We examined the utility of an immunoregulatory gene panel to discriminate between tolerance and rejection. We observed that Treg-associated genes (foxp3, lag3, tgf-β and fgl2) had increased expression and pro-inflammatory genes (ifn-γ and gzmb) had decreased expression in tolerant compared with rejecting allografts. Taken together, these data strongly suggest that Treg cells expressing FGL2 mediate rapamycin-induced tolerance. Furthermore, a gene biomarker panel that includes fgl2 can distinguish between rejecting and tolerant grafts. PMID:24990517

Interleukin-35: Expanding Its Job Profile

PubMed Central

Sawant, Deepali V.; Hamilton, Kristia

2015-01-01

Counter-regulation afforded by specialized regulatory cell populations and immunosuppressive cytokines is critical for balancing immune outcome. The inhibitory potential of the established suppressive cytokines, IL-10 and TGFβ, has been well elucidated in diverse inflammatory scenarios in conjunction with their key roles in Treg development and function. Despite the early predictions for an immunomodulatory role for the Ebi3/p35 heterodimer in placental trophoblasts, IL-35 biology remained elusive until 2007 when it was established as a Treg-restricted inhibitory cytokine. Since then, Treg-derived IL-35 has been shown to exhibit its suppressive activities in a range of autoimmune diseases and cancer models. Recent studies are beginning to explore other cellular sources of IL-35, such as Bregs and CD8+ Tregs. Despite these new cellular sources and targets, the mode of IL-35 suppression remains restricted to inhibition of proliferation and induction of an IL-35-producing induced regulatory T cell population referred to as iTr35. In this review, we explore the early beginnings, status quo, and future prospects of IL-35 biology. The unparalleled opportunity of targeting multiple immunosuppressive populations (Tregs, Bregs, CD8+ Tregs) through IL-35 is highly exciting and offers tremendous promise from a translational standpoint, particularly for cancer immunotherapies. PMID:25919641

Modulation of Regulatory T Cell Activity by TNF Receptor Type II-Targeting Pharmacological Agents

PubMed Central

Zou, Huimin; Li, Ruixin; Hu, Hao; Hu, Yuanjia; Chen, Xin

2018-01-01

There is now compelling evidence that tumor necrosis factor (TNF)–TNF receptor type II (TNFR2) interaction plays a decisive role in the activation, expansion, and phenotypical stability of suppressive CD4+Foxp3+ regulatory T cells (Tregs). In an effort to translate this basic research finding into a therapeutic benefit, a number of agonistic or antagonistic TNFR2-targeting biological agents with the capacity to activate or inhibit Treg activity have been developed and studied. Recent studies also show that thalidomide analogs, cyclophosphamide, and other small molecules are able to act on TNFR2, resulting in the elimination of TNFR2-expressing Tregs. In contrast, pharmacological agents, such as vitamin D3 and adalimumab, were reported to induce the expansion of Tregs by promoting the interaction of transmembrane TNF (tmTNF) with TNFR2. These studies clearly show that TNFR2-targeting pharmacological agents represent an effective approach to modulating the function of Tregs and thus may be useful in the treatment of major human diseases such as autoimmune disorders, graft-versus-host disease (GVHD), and cancer. In this review, we will summarize and discuss the latest progress in the study of TNFR2-targeting pharmacological agents and their therapeutic potential based on upregulation or downregulation of Treg activity. PMID:29632537

Distinct pattern of Th17/Treg cells in pregnant women with a history of unexplained recurrent spontaneous abortion.

PubMed

Qian, Jinfeng; Zhang, Na; Lin, Jing; Wang, Caiyan; Pan, Xinyao; Chen, Lanting; Li, Dajin; Wang, Ling

2018-05-13

The aim of the current study was to determine the pattern of immune cells and related functional molecules in peripheral blood and at the maternal-fetal interface in women with unexplained recurrent spontaneous abortion (URSA). In part I, 155 women were included and divided into four groups: non-pregnant controls with no history of URSA (NPCs), pregnant controls with no history of URSA (PCs), non-pregnant women with a history of URSA (NPUs), and pregnant women with a history of URSA (PUs). Venous blood samples were collected and analyzed. In part II, 35 subjects with URSA and 40 subjects in the early stage of normal pregnancy who chose to undergo an abortion were recruited. Samples of the decidua were collected, and the proportion of immune cells and the expression of related molecules were evaluated. Peripheral regulatory T cells (Treg cells) increased in PCs compared to NPCs, but in women with URSA the flux of Treg cells disappeared when pregnancy occurred. Levels of interleukin-10 (IL-10), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and IL-17 and the ratio of Th17/Treg cells in peripheral blood remained stable among the four groups. At the maternal-fetal interface, the percentage of Treg cells, the level of CTLA-4 of CD4 + CD25 + CD127 lo cells and CD4 + Foxp3 + cells were significantly lower in women with URSA compared to controls, respectively. Levels of transforming growth factor-β1 (TGF-β1) mRNA and protein in the decidua significantly decreased in URSA while levels of IL-6 and tumor necrosis factor-ɑ (TNF-ɑ) and the Th17/Treg ratio significantly increased. In conclusion, peripheral Treg cells did not increase in pregnant women with URSA. The decrease in Treg cells and levels of CTLA-4 and TGF-β1 and as well as the increase in levels of IL-6 and TNF-ɑ, and the Th17/Treg ratio at the maternal-fetal interface might contribute to inappropriate maternal-fetal immune tolerance in URSA.

Immunotherapy using regulatory T cells in cancer suggests more flavors of hypersensitivity type IV.

PubMed

Pakravan, Nafiseh; Hassan, Zuhair Mohammad

2018-03-01

Regulatory T cells (Tregs) profoundly affect tumor microenvironment and exert dominant suppression over antitumor immunity in response to self-antigen expressed by tumor. Immunotherapy targeting Tregs lead to a significant improvement in antitumor immunity. Intradermal injection of tumor antigen results in negative delayed-type hypersensitivity (DTH) type IV. However, anti-Tregs treatment/use of adjuvant along with tumor antigens turns DTH to positive. Considering Tregs as the earliest tumor sensor/responders, tumor can be regarded as Treg-mediated type IV hypersensitivity and negative DTH to tumor antigen is due to anti-inflammatory action of Tregs to tumor antigens at the injection site. Such a view would help us in basic and clinical situations to testify a candidate vaccine via dermal administration and evaluation of Treg proportion at injection site.

Death receptor 3 signaling enhances proliferation of human regulatory T cells.

PubMed

Bittner, Sebastian; Knoll, Gertrud; Ehrenschwender, Martin

2017-04-01

Exploiting regulatory T cells (Tregs) to control aberrant immune reactions is a promising therapeutic approach, but is hampered by their relative paucity. In mice, activation of death receptor 3 (DR3), a member of the TNF-receptor superfamily (TNFRSF), increases Treg frequency and efficiently controls exuberant immune activation. For human Tregs, neither DR3 expression nor potential functions have been described. Here, we show that human Tregs express DR3 and demonstrate DR3-mediated activation of p38, ERK, and NFκB. DR3 stimulation enhances Treg expansion ex vivo while retaining their suppressive capacity. In summary, our results establish a functional role for DR3 signaling in human Tregs and could potentially help to tailor Treg-based therapies. © 2017 Federation of European Biochemical Societies.

The effect of cellular isolation and cryopreservation on the expression of markers identifying subsets of regulatory T cells.

PubMed

Zhang, Weiying; Nilles, Tricia L; Johnson, Jacquett R; Margolick, Joseph B

2016-04-01

The role of CD4(+) regulatory T cells (Tregs) and their subsets during HIV infection is controversial. Cryopreserved peripheral blood mononuclear cells (PBMC) are an important source for assessing number and function of Tregs. However, it is unknown if PBMC isolation and cryopreservation affect the expression of CD120b and CD39, markers that identify specific subsets of Tregs. HIV-uninfected (HIV-) and -infected (HIV+) men were randomly selected from the Multicenter AIDS Cohort Study (MACS). Percentages of CD120b(+) and CD39(+) Tregs measured by flow cytometry in whole blood and in corresponding fresh and cryopreserved PBMC were compared. Percentages of CD120b(+) Tregs were significantly lower in a) fresh PBMC relative to whole blood, and b) freshly thawed frozen PBMC relative to fresh PBMC when the recovery of viable cryopreserved cells was low. When present, low expression of CD120b in frozen PBMC was reversible by 4h of in vitro culture. In contrast, expression of CD39 on Tregs was not affected by isolation and/or cryopreservation of PBMC, or by relative recovery of cryopreserved PBMC. These findings were unaffected by the HIV status of the donor. The data suggest that percentages of CD120b(+) Tregs and CD39(+) Tregs can be validly measured in either whole blood or PBMC (fresh and frozen) in HIV- and HIV+ men. However, for measurement of CD120b(+) Tregs one type of sample should be used consistently within a given study, and thawed frozen cells may require in vitro culture if recovery of viable cells is low. Copyright © 2016 Elsevier B.V. All rights reserved.

Critical role for TNF in the induction of human antigen-specific regulatory T cells by tolerogenic dendritic cells.

PubMed

Kleijwegt, Fleur S; Laban, Sandra; Duinkerken, Gaby; Joosten, Antoinette M; Zaldumbide, Arnaud; Nikolic, Tatjana; Roep, Bart O

2010-08-01

TNF is a pleiotropic cytokine with differential effects on immune cells and diseases. Anti-TNF therapy was shown to be effective in rheumatoid arthritis but proved inefficient or even detrimental in other autoimmune diseases. We studied the role of TNF in the induction of Ag-specific regulatory T cells (Tregs) by tolerogenic vitamin D3-modulated human dendritic cells (VD3-DCs), which previously were shown to release high amounts of soluble TNF (sTNF) upon maturation with LPS. First, production of TNF by modulated VD3-DCs was analyzed upon maturation with LPS or CD40L with respect to both secreted (cleaved) TNF (sTNF) and expression of the membrane-bound (uncleaved) form of TNF (mTNF). Next, TNF antagonists were tested for their effect on induction of Ag-specific Tregs by modulated DCs and the subsequent functionality of these Tregs. VD3-DCs expressed greater amounts of mTNF than did control DCs (nontreated DCs), independent of the maturation protocol. Inhibition of TNF with anti-TNF Ab (blocking both sTNF and mTNF) during the priming of Tregs with VD3-DCs prevented generation of Tregs and their suppression of proliferation of CD4(+) T cells. In contrast, sTNF receptor II (sTNFRII), mainly blocking sTNF, did not change the suppressive capacity of Tregs. Blocking of TNFRII by anti-CD120b Ab during Treg induction similarly abrogated their subsequent suppressive function. These data point to a specific role for mTNF on VD3-DCs in the induction of Ag-specific Tregs. Interaction between mTNF and TNFRII instructs the induction of suppressive Tregs by VD3-DCs. Anti-TNF therapy may therefore act adversely in different patients or disease pathways.

CXCL12 mediates immunosuppression in the lymphoma microenvironment after allogeneic transplantation of hematopoietic cells.

PubMed

Dürr, Christoph; Pfeifer, Dietmar; Claus, Rainer; Schmitt-Graeff, Annette; Gerlach, Ulrike V; Graeser, Ralph; Krüger, Sophie; Gerbitz, Armin; Negrin, Robert S; Finke, Jürgen; Zeiser, Robert

2010-12-15

Clinical studies indicate a role of allogeneic hematopoietic cell transplantation (alloHCT) for patients with refractory or recurrent B-cell lymphoma (BCL) indicative of a graft-versus-tumor effect. However, the relevance of local immunosuppression in the BCL microenvironment by donor-derived regulatory T cells (Treg) after alloHCT is unclear. Therefore, we studied Treg recruitment after alloHCT in different murine BCL models and the impact of lymphoma-derived chemoattractive signals. Luciferase transgenic Tregs accumulated in murine BCL microenvironment and microarray-based analysis of BCL tissues revealed increased expression of CXCL9, CXCL10, and CXCL12. In vivo blocking identified the CXCR4/CXCL12 axis as being critical for Treg attraction toward BCL. In contrast to Tregs, effector T cells displayed low levels of CXCR4 and were not affected by the pharmacologic blockade. Most important, blocking CXCR4 not only reduced Treg migration toward tumor tissue but also enhanced antitumor responses after alloHCT. CXCL12 production was dependent on antigen-presenting cells (APC) located in the lymphoma microenvironment, and their diphtheria-toxin receptor (DTR)-based depletion in CD11c.DTR-Tg mice significantly reduced Treg accumulation within BCL tissue. CXCL12 was also detected in human diffuse, large BCL tissues indicative of its potential clinical relevance. In conclusion, we demonstrate that Tregs are recruited toward BCL after alloHCT by infiltrating host APCs in a CXCL12-dependent fashion. Blocking CXCR4 enhanced antitumor effects and prolonged survival of tumor-bearing mice by reducing local Treg accumulation, indicating that CXCR4 is a potential target to interfere with tumor escape after alloHCT. ©2010 AACR.

Fatigue is not associated with impaired function of regulatory T cells in untreated patients with multiple sclerosis.

PubMed

Yaldizli, Ozguer; Kumar, Manoj; Vago, Susanne; Kreuzfelder, Erich; Limmroth, Volker; Putzki, Norman

2009-01-01

The pathophysiology of multiple sclerosis (MS)-associated fatigue is poorly understood. Immunological mechanisms may play a role. Alterations in immunological profile indicate a chronic immune activation in MS patients with fatigue. T-regulatory (Treg) cells seem to play a key role in coordinating autoimmune mechanisms in MS. This is the first study investigating the relationship between Treg cell function and fatigue in MS patients. In this cross-sectional in vitro, ex vivo study, we isolated peripheral blood mononuclear cells (PBMCs) from 20 MS patients with fatigue, determined lymphocyte subsets by flow cytometry and suppressive function of Treg cells in PBMC cultures with antigen stimulation. Forkhead box protein 3 expression was evaluated by PCR. Results were compared with 20 MS patients without fatigue and with 19 healthy controls. Leukocytes and lymphocyte subsets including Treg cell frequency did not differ in patients with and without fatigue. Co-culturing of Treg cells with CD4+CD25- cells did not lead to a significant suppression of myelin basic protein- and pokeweed mitogen-induced proliferation in MS patients in contrast to healthy controls. There were no statistical differences between MS patients with and without fatigue regarding this suppression activity. Fatigue seems not to be associated with impaired function of Treg cells in untreated MS patients.

Thioredoxin induces Tregs to generate an immunotolerant tumor microenvironment in metastatic melanoma

PubMed Central

Wang, Xiaogang; Dong, Haisheng; Li, Qi; Li, Yingxian; Hong, An

2015-01-01

Metastatic melanoma is a highly aggressive cancer that is very difficult to treat. Additionally, the antitumor immune reaction of melanoma is still unclear. Here we demonstrate an association between the expression and secretion of the antioxidant protein thioredoxin (TRX) and increasing tumor stage and metastasis in melanoma. To elucidate the role of TRX in melanoma, we assessed the correlation of TRX expression with different disease parameters in melanoma. We also examined the in vitro and in vivo effects of modulating TRX levels in melanoma cells using various methods of TRX depletion and augmentation. We further explored the effects of TRX on the cytokine milieu and the ability of TRX to regulate the proportion and specific activities of T-cell populations. We demonstrate that TRX expression correlates with Treg representation in clinical samples and, that modulation of TRX influences the induction of Tregs and the generation of an immunotolerant cytokine profile in mouse serum. Using a murine metastatic melanoma model, we identified a tumor immunoevasion mechanism whereby melanoma cell-secreted TRX enhances Treg infiltration. TRX displays chemotactic effects in recruiting Tregs, stimulates the conversion of conventional T cells to Tregs, and confers survival advantage to Tregs in the tumor microenvironment. In turn, this increase of Tregs generates immunotolerance in tissues and therefore decreases antitumor immune reactions. These results elucidate a mechanism by which TRX promotes metastatic melanoma in part through Treg recruitment to inhibit T-cell antitumor effects and suggest that TRX antibody may be useful in the clinic as a therapy against melanoma. PMID:26405597

An Epistatic Interaction between Themis1 and Vav1 Modulates Regulatory T Cell Function and Inflammatory Bowel Disease Development.

PubMed

Pedros, Christophe; Gaud, Guillaume; Bernard, Isabelle; Kassem, Sahar; Chabod, Marianne; Lagrange, Dominique; Andréoletti, Olivier; Dejean, Anne S; Lesourne, Renaud; Fournié, Gilbert J; Saoudi, Abdelhadi

2015-08-15

The development of inflammatory diseases depends on complex interactions between several genes and various environmental factors. Discovering new genetic risk factors and understanding the mechanisms whereby they influence disease development is of paramount importance. We previously reported that deficiency in Themis1, a new actor of TCR signaling, impairs regulatory T cell (Treg) function and predisposes Brown-Norway (BN) rats to spontaneous inflammatory bowel disease (IBD). In this study, we reveal that the epistasis between Themis1 and Vav1 controls the occurrence of these phenotypes. Indeed, by contrast with BN rats, Themis1 deficiency in Lewis rats neither impairs Treg suppressive functions nor induces pathological manifestations. By using congenic lines on the BN genomic background, we show that the impact of Themis1 deficiency on Treg suppressive functions depends on a 117-kb interval coding for a R63W polymorphism that impacts Vav1 expression and functions. Indeed, the introduction of a 117-kb interval containing the Lewis Vav1-R63 variant restores Treg function and protects Themis1-deficient BN rats from spontaneous IBD development. We further show that Themis1 binds more efficiently to the BN Vav1-W63 variant and is required to stabilize its recruitment to the transmembrane adaptor LAT and to fully promote the activation of Erk kinases. Together, these results highlight the importance of the signaling pathway involving epistasis between Themis1 and Vav1 in the control of Treg suppressive function and susceptibility to IBD development. Copyright © 2015 by The American Association of Immunologists, Inc.

Bet v 1-specific T-cell receptor/forkhead box protein 3 transgenic T cells suppress Bet v 1-specific T-cell effector function in an activation-dependent manner.

PubMed

Schmetterer, Klaus G; Haiderer, Daniela; Leb-Reichl, Victoria M; Neunkirchner, Alina; Jahn-Schmid, Beatrice; Küng, Hans J; Schuch, Karina; Steinberger, Peter; Bohle, Barbara; Pickl, Winfried F

2011-01-01

Regulatory T (Treg) cells establish and maintain tolerance to self-antigens and many foreign antigens, such as allergens, by suppressing effector T-cell proliferation and function. We have previously shown that human T-cell receptor (TCR) αβ-chains specific for allergen-derived epitopes confer allergen specificity on peripheral blood T cells of individuals with and without allergy. To study the feasibility of generating allergen-specific human Treg cells by retroviral transduction of a transcription unit encoding forkhead box protein 3 (FOXP3) and allergen-specific TCR αβ-chains. cDNAs encoding the α and β-chains of a Bet v 1(142-153)-specific TCR (TCR alpha variable region 6/TCR beta variable region 20) and human FOXP3 were linked via picornaviral 2A sequences and expressed as single translational unit from an internal ribosomal entry site-green fluorescence protein-containing retroviral vector. Retrovirally transduced peripheral blood T cells were tested for expression of transgenes, Treg phenotype, and regulatory capacity toward allergen-specific effector T cells. Transduced T cells displayed a Treg phenotype with clear-cut upregulation of CD25, CD39, and cytotoxic T-lymphocyte antigen 4. The transduced cells were hyporesponsive in cytokine production and secretion and, like naturally occurring Treg cells, did not proliferate after antigen-specific or antigen-mimetic stimulation. However, proliferation was inducible upon exposure to exogenous IL-2. In coculture experiments, TRAV6(+)TRBV20(+)FOXP3(+) transgenic T cells, unlike FOXP3(+) single transgenic T cells or naturally occurring Treg cells, highly significantly suppressed T cell cytokine production and proliferation of corresponding allergen-specific effector T cells in an allergen-specific, dose-dependent manner. We demonstrate a transgenic approach to engineer human allergen-specific Treg cells that exert their regulatory function in an activation-dependent manner. Customized Treg cells might become useful for tolerance induction therapies in individuals with allergic and other immune-mediated diseases. Copyright © 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Lysosomal-associated Transmembrane Protein 4B (LAPTM4B) Decreases Transforming Growth Factor β1 (TGF-β1) Production in Human Regulatory T Cells.

PubMed

Huygens, Caroline; Liénart, Stéphanie; Dedobbeleer, Olivier; Stockis, Julie; Gauthy, Emilie; Coulie, Pierre G; Lucas, Sophie

2015-08-14

Production of active TGF-β1 is one mechanism by which human regulatory T cells (Tregs) suppress immune responses. This production is regulated by glycoprotein A repetitions predominant (GARP), a transmembrane protein present on stimulated Tregs but not on other T lymphocytes (Th and CTLs). GARP forms disulfide bonds with proTGF-β1, favors its cleavage into latent inactive TGF-β1, induces the secretion and surface presentation of GARP·latent TGF-β1 complexes, and is required for activation of the cytokine in Tregs. We explored whether additional Treg-specific protein(s) associated with GARP·TGF-β1 complexes regulate TGF-β1 production in Tregs. We searched for such proteins by yeast two-hybrid assay, using GARP as a bait to screen a human Treg cDNA library. We identified lysosomal-associated transmembrane protein 4B (LAPTM4B), which interacts with GARP in mammalian cells and is expressed at higher levels in Tregs than in Th cells. LAPTM4B decreases cleavage of proTGF-β1, secretion of soluble latent TGF-β1, and surface presentation of GARP·TGF-β1 complexes by Tregs but does not contribute to TGF-β1 activation. Therefore, LAPTM4B binds to GARP and is a negative regulator of TGF-β1 production in human Tregs. It may play a role in the control of immune responses by decreasing Treg immunosuppression. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Regulatory T Cells in Chronic Graft-Versus-Host Disease After Extracorporeal Photopheresis: Correlation With Skin and Global Organ Responses, and Ability to Taper Steroids.

PubMed

Denney, Helen A; Whittle, Robert J; Lai, Jennifer; Jacques, Richard M; Taylor, Peter C

2017-01-01

Induction of immune tolerance by an increase in regulatory T (Treg) cells after extracorporeal photopheresis (ECP) is thought to contribute to how ECP exerts its therapeutic effect in patients with chronic graft-versus-host disease (cGvHD). We investigated whether percentages and absolute counts of Treg cells changed post-ECP, and examined correlation with response. Absolute counts and % of CD4+ T cells and Treg cells (CD4 + CD25 + FOXP3 + CD127dim/-) were evaluated using flow cytometry in 32 patients with cGvHD treated by ECP for a minimum of 3 months, and up to 12 months. CD4+ or Treg cells at baseline to 12 months post-ECP were compared with changes in skin disease scores or global organ involvement, or the ability to taper steroids, at 14, 28, and 56 weeks. Regulatory T cells % increased significantly above any overall changes in CD4+ % at 6, 9, and 12 months post-ECP. There was no statistically significant association between Treg cells and skin or steroid response, whereas a larger increase in CD4+ count from baseline to 1 to 3 months corresponded to increased odds of being able to reduce steroid dose by 50% or greater at 14 weeks. Skin and global organ responders at 28 weeks had higher median Treg cell counts 3 months post-ECP than nonresponders, as did steroid responders at 56 weeks who were 12 months post-ECP. Regulatory T cell counts and % varied greatly among cGvHD patients, and the increase post-ECP was not significant until 6 months. No clear correlation was found between Treg cells and clinical improvement, suggesting that increases in Treg cell numbers and/or proportions are not driving the mechanism leading to a response after ECP.

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

PubMed

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.

Innovative Strategies for Breast Cancer Immunotherapy

DTIC Science & Technology

2014-09-01

donors, percentages of CD4+ and CD8+ T cells as well as T regulatory cells ( Tregs : FOXP3 and CD25 positive) were determined in K-CAR T cells...obtained from BC patients or normal female donors, since Tregs are a component of the immune system that suppresses immune responses of other cells. A...immunosuppressive mechanisms that inhibit T cell activation (33). Suppression of CD8+ effector cells by CD4+CD25+FoxP3+ regulatory T cells ( Tregs ) plays a key role

Generation, cryopreservation, function and in vivo persistence of ex-vivo expanded cynomolgus monkey regulatory T cells

PubMed Central

Guo, Hao; Zhang, Hong; Lu, Lien; Ezzelarab, Mohamed B.; Thomson, Angus W.

2015-01-01

We expanded flow-sorted Foxp3+ cynomolgus monkey regulatory T cells (Treg) >1000-fold after three rounds of stimulation with anti-CD3 mAb-loaded artificial antigen-presenting cells, rapamycin (first round only) and IL-2. The expanded Treg maintained their expression of Treg signature markers, CD25, CD27, CD39, Foxp3, Helios, and CTLA-4, as well as CXCR3, which plays an important role in T cell migration to sites of inflammation. In contrast to expanded effector T cells (Teff), expanded Treg produced minimal IFN-γ and IL-17 and no IL-2 and potently suppressed Teff proliferation. Following cryopreservation, thawed Treg were less viable than their freshly-expanded counterparts, although no significant changes in phenotype or suppressive ability were observed. Additional rounds of stimulation/expansion restored maximal viability. Furthermore, adoptively-transferred autologous Treg expanded from cryopreserved second round stocks and labeled with CFSE or VPD450 were detected in blood and secondary lymphoid tissues of normal or immunosuppressed recipients at least two months after their systemic infusion. PMID:25732601

Helios expression and Foxp3 TSDR methylation of IFNy+ and IFNy- Treg from kidney transplant recipients with good long-term graft function.

PubMed

Trojan, Karina; Unterrainer, Christian; Weimer, Rolf; Bulut, Nuray; Morath, Christian; Aly, Mostafa; Zhu, Li; Opelz, Gerhard; Daniel, Volker

2017-01-01

There is circumstantial evidence that IFNy+ Treg might have clinical relevance in transplantation. IFNy+ Treg express IFNy receptors and are induced by IFNy. In the present study we investigated in kidney transplant recipients with good long-term stable graft function the absolute cell counts of IFNy+ Treg subsets and whether their expression of Foxp3 is stable or transient. Helios expression determined by eight-color-fluorescence flow cytometry and methylation status of the Foxp3 Treg specific demethylation region (TSDR) served as indicators for stability of Foxp3 expression. Methylation status was investigated in enriched IFNy+ and IFNy- Treg preparations originating from peripheral blood using high resolution melt analysis. A total of 136 transplant recipients and 52 healthy controls were studied. Proportions of IFNy+ Treg were similar in patients and healthy controls (0.05% and 0.04% of all CD4+ lymphocytes; p = n.s.). Patients also had similar absolute counts of IFNy producing Helios+ and Helios- Treg (p = n.s.). Most of the IFNy+ and IFNy- Treg in transplant recipients had a methylated Foxp3 TSDR, however, there was a sizeable proportion of IFNy+ and IFNy- Treg with demethylated Foxp3 TSDR. Male and female patients showed more frequently methylated IFNy+ and IFNy- Treg than male and female controls (all p<0.05). Kidney transplant recipients with good long-term stable graft function have similar levels of IFNy+ Treg as healthy controls. IFNy+ and IFNy- Treg subsets in patients consist of cells with stable and cells with transient Foxp3 expression; however, patients showed more frequently methylated IFNy+ and IFNy- Treg than controls. The data show increased levels of Treg subsets with stable as well as transient Foxp3 expression in patients with stable allograft acceptance compared to healthy controls.

The effects of cryopreservation on the expression of canine regulatory T-cell markers.

PubMed

Tarpataki, Noemi; Wawrzyniak, Marcin; Akdis, Cezmi A; Rückert, Beate; Meli, Marina L; Fischer, Nina M; Favrot, Claude; Rostaher, Ana

2017-08-01

Regulatory T (Treg) cells have been described as key regulators in various immunological processes and are of growing interest in veterinary allergy. Cryopreservation of immune cells is performed routinely in human basic science research and in clinical studies. As such, it allows batch testing of collected samples at a single time point, resulting in a significant reduction in sample variability. Data which describe the effects of cryopreservation on Treg cell frequency and functionality in the canine species are important to inform future research. The purpose of this study was to establish a robust freeze/thaw procedure and flow cytometric staining protocol for canine Treg cells, and to compare the frequencies of different canine Treg cell phenotypes before and after cryopreservation. Nine privately owned dogs. Peripheral blood mononuclear cells were isolated and Treg cells stained and analysed by flow cytometry, before and after three months of cryopreservation. The recovery percentages and the corresponding correlations (fresh versus cryopreserved) for CD4 + CD25 + , CD4 + FOXP3 + and CD4 + CD25 + FOXP3 + cell populations were calculated. A high recovery rate of 97.2 (r = 0.94, P < 0.0001), 93.9 (r = 0.77, P < 0.01) and 101.7% (r = 0.99, P < 0.0001) for CD4 + CD25 + , CD4 + FOXP3 + and CD4 + CD25 + FOXP3 + cell populations, respectively, was observed. This study demonstrates an optimized protocol for freezing, thawing and quantifying canine Treg cells. These results indicate that cryopreservation does not substantially affect the expression of surface and intracellular markers of canine Treg cells; however, additional studies will be necessary to assess whether functionality of the cells is also maintained. © 2017 ESVD and ACVD.

Cord blood derived CD4+ CD25(high) T cells become functional regulatory T cells upon antigen encounter.

PubMed

Mayer, Elisabeth; Bannert, Christina; Gruber, Saskia; Klunker, Sven; Spittler, Andreas; Akdis, Cezmi A; Szépfalusi, Zsolt; Eiwegger, Thomas

2012-01-01

Upon antigen exposure, cord blood derived T cells respond to ubiquitous environmental antigens by high proliferation. To date it remains unclear whether these "excessive" responses relate to different regulatory properties of the putative T regulatory cell (Treg) compartment or even expansion of the Treg compartment itself. Cord blood (>37 week of gestation) and peripheral blood (healthy controls) were obtained and different Treg cell subsets were isolated. The suppressive potential of Treg populations after antigen exposure was evaluated via functional inhibition assays ([(3)H]thymidine incorporation assay and CFSE staining) with or without allergen stimulation. The frequency and markers of CD4(+)CD25(high)FoxP3(+) T cells were characterized by mRNA analysis and flow cytometry. Cord blood derived CD4(+)CD25(high) cells did not show substantial suppressor capacity upon TCR activation, in contrast to CD4(+)CD25(high) cells freshly purified from adult blood. This could not be explained by a lower frequency of FoxP3(+)CD4(+)CD25(high)cells or FOXP3 mRNA expression. However, after antigen-specific stimulation in vitro, these cells showed strong proliferation and expansion and gained potent suppressive properties. The efficiency of their suppressive capacity can be enhanced in the presence of endotoxins. If T-cells were sorted according to their CD127 expression, a tiny subset of Treg cells (CD4(+)CD25(+)CD127(low)) is highly suppressive even without prior antigen exposure. Cord blood harbors a very small subset of CD4(+)CD25(high) Treg cells that requires antigen-stimulation to show expansion and become functional suppressive Tregs.

Metabolism of murine TH 17 cells: Impact on cell fate and function.

PubMed

Wang, Ran; Solt, Laura A

2016-04-01

An effective adaptive immune response relies on the ability of lymphocytes to rapidly act upon a variety of insults. In T lymphocytes, this response includes cell growth, clonal expansion, differentiation, and cytokine production, all of which place a significant energy burden on the cell. Recent evidence shows that T-cell metabolic reprogramming is an essential component of the adaptive immune response and specific metabolic pathways dictate T-cell fate decisions, including the development of TH 17 versus T regulatory (Treg) cells. TH 17 cells have garnered significant attention due to their roles in the pathology of immune-mediated inflammatory diseases. Attempts to characterize TH 17 cells have demonstrated that they are highly dynamic, adjusting their function to environmental cues, which dictate their metabolic program. In this review, we highlight recent data demonstrating the impact of cellular metabolism on the TH 17/Treg balance and present factors that mediate TH 17-cell metabolism. Some examples of these include the differential impact of the mTOR signaling complexes on T-helper-cell differentiation, hypoxia inducible factor 1 alpha (HIF1α) promotion of glycolysis to favor TH 17-cell development, and ACC1-dependent de novo fatty acid synthesis favoring TH 17-cell development over Treg cells. Finally, we discuss the potential therapeutic options and the implications of modulating TH 17-cell metabolism for the treatment of TH 17-mediated diseases. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

PubMed Central

2010-01-01

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. PMID:20137067

Freeze and Thaw of CD4+CD25+Foxp3+ Regulatory T Cells Results in Loss of CD62L Expression and a Reduced Capacity to Protect against Graft-versus-Host Disease

PubMed Central

Pierini, Antonio; Baker, Jeanette; Armstrong, Randall; Pan, Yuqiong; Leveson-Gower, Dennis; Negrin, Robert; Meyer, Everett

2015-01-01

The adoptive transfer of CD4+CD25+Foxp3+ regulatory T cells (Tregs) in murine models of allogeneic hematopoietic cell transplantation (HCT) has been shown to protect recipient mice from lethal acute graft-versus-host disease (GVHD) and this approach is being actively investigated in human clinical trials. Here, we examined the effects of cryopreservation on Tregs. We found that freeze and thaw of murine and human Tregs is associated with reduced expression of L-selectin (CD62L), which was previously established to be an important factor that contributes to the in vivo protective effects of Tregs. Frozen and thawed murine Tregs showed a reduced capacity to bind to the CD62L binding partner MADCAM1 in vitro as well as an impaired homing to secondary lymphoid organs in vivo. Upon adoptive transfer frozen and thawed Tregs failed to protect against lethal GVHD compared with fresh Tregs in a murine model of allogeneic HCT across major histocompatibility barriers. In summary, the direct administration of adoptively transferred frozen and thawed Tregs adversely affects their immunosuppressive potential which is an important factor to consider in the clinical implementation of Treg immunotherapies. PMID:26693907

Induced miR-99a expression represses Mtor cooperatively with miR-150 to promote regulatory T-cell differentiation

PubMed Central

Warth, Sebastian C; Hoefig, Kai P; Hiekel, Anian; Schallenberg, Sonja; Jovanovic, Ksenija; Klein, Ludger; Kretschmer, Karsten; Ansel, K Mark; Heissmeyer, Vigo

2015-01-01

Peripheral induction of regulatory T (Treg) cells provides essential protection from inappropriate immune responses. CD4+ T cells that lack endogenous miRNAs are impaired to differentiate into Treg cells, but the relevant miRNAs are unknown. We performed an overexpression screen with T-cell-expressed miRNAs in naive mouse CD4+ T cells undergoing Treg differentiation. Among 130 candidates, the screen identified 29 miRNAs with a negative and 10 miRNAs with a positive effect. Testing reciprocal Th17 differentiation revealed specific functions for miR-100, miR-99a and miR-10b, since all of these promoted the Treg and inhibited the Th17 program without impacting on viability, proliferation and activation. miR-99a cooperated with miR-150 to repress the expression of the Th17-promoting factor mTOR. The comparably low expression of miR-99a was strongly increased by the Treg cell inducer “retinoic acid”, and the abundantly expressed miR-150 could only repress Mtor in the presence of miR-99a. Our data suggest that induction of Treg cell differentiation is regulated by a miRNA network, which involves cooperation of constitutively expressed as well as inducible miRNAs. PMID:25712478

Aberrant Muscle Antigen Exposure in Mice Is Sufficient to Cause Myositis in a Treg Cell–Deficient Milieu

PubMed Central

Young, Nicholas A; Sharma, Rahul; Friedman, Alexandra K; Kaffenberger, Benjamin H; Bolon, Brad; Jarjour, Wael N

2013-01-01

Objective Myositis is associated with muscle-targeted inflammation and is observed in some Treg cell–deficient mouse models. Because an autoimmune pathogenesis has been strongly implicated, the aim of this study was to investigate the hypothesis that abnormal exposure to muscle antigens, as observed in muscle injury, can induce autoimmune-mediated myositis in susceptible hosts. Methods FoxP3 mutant (scurfy) mice were mated to synaptotagmin VII (Syt VII) mutant mice, which resulted in a new mouse strain that combines impaired membrane resealing with Treg cell deficiency. Lymphocyte preparations from double-mutant mice were adoptively transferred intraperitoneally, with or without purified Treg cells, into recombination-activating gene 1 (RAG-1)–null recipients. Lymph node cells from mice with the FoxP3 mutation were transferred into RAG-1–null mice either 1) intraperitoneally in conjunction with muscle homogenate or purified myosin protein or 2) intramuscularly with or without cotransfer of purified Treg cells. Results FoxP3-deficient mouse lymph node cells transferred in conjunction with myosin protein or muscle homogenate induced robust skeletal muscle inflammation. The infiltrates consisted predominantly of CD4+ and CD8+ T cells, a limited number of macrophages, and no B cells. Significant inflammation was also seen in similar experiments using lymph node cells from FoxP3/Syt VII double-mutant mice but was absent in experiments using adoptive transfer of FoxP3 mutant mouse cells alone. The cotransfer of Treg cells completely suppressed myositis. Conclusion These data, derived from a new, reproducible model, demonstrate the critical roles of Treg cell deficiency and aberrant muscle antigen exposure in the priming of autoreactive cells to induce myositis. This mouse system has multifaceted potential for examining the interplay in vivo between tissue injury and autoimmunity. PMID:24022275

Circulating T-Regulatory Cells, Exercise and the Elite Adolescent Swimmer

PubMed Central

Wilson, Lori D.; Zaldivar, Frank P.; Schwindt, Christina D.; Wang-Rodriguez, Jessica; Cooper, Dan M.

2014-01-01

Brief high intensity exercise induces peripheral leukocytosis possibly leading to a higher incidence of allergic symptoms in athletes undergoing excessive training. We studied the exercise-induced alternation of circulating Tregs and FoxP3+ Tregs due to acute intense swim exercise in elite swimmers (n = 22, 12 males, age = 15.4 yrs). Twelve had prior or current rhinitis or asthma and 10 had no current or prior allergy or asthma. Circulating Tregs increased significantly (p < .001) following exercise (pre = 133 ± 11.2, post = 196 ± 17.6) as did FoxP3+ cells (pre = 44, post = 64 cells/µl). Increases in Tregs and FoxP3+ Tregs occurred to the same extent in both groups of adolescent swimmers. PMID:19827454

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

PubMed

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.

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

PubMed Central

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

2016-01-01

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. PMID:27410049

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

PubMed

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.

The effect of a probiotic Escherichia coli strain on regulatory T-cells in six year-old children.

PubMed

Hrdý, J; Kocourková, I; Lodinová-Žádníková, R; Kolářová, L; Prokešová, L

2016-11-30

Probiotics are believed to prevent or reduce allergy development but the mechanism of their beneficial effect is still poorly understood. Immune characteristics of regulatory T cells (Tregs) in peripheral blood of perinatally probiotic-supplemented children of allergic mothers (51 children), non-supplemented children of allergic mothers (42 children), and non-supplemented children of healthy mothers (28 children) were compared at the age of 6-7 years. A first dose of a probiotic Escherichia coli strain (E. coli O83:K24:H31) was administered within 2 days after the birth and then 12 times during the first months of life and children were followed longitudinally. Proportion and functional properties of Tregs were estimated by flow cytometry in relation to the children's allergy status. Proportion of Tregs in the peripheral blood of children suffering from allergy tends to be higher whereas median of fluorescence intensity (MFI) of FoxP3 was significantly decreased in allergic group. Intracellular presence of regulatory cytokine interleukin (IL)-10 was also lower in allergic children. Immune functions of Tregs reflected by both MFI of FoxP3 and IL-10 in the group of probiotic-supplemented children of allergic mothers were nearly comparable with children of healthy mothers while probiotic non-supplemented children of allergic mothers have decreased immune function of Tregs. Supplementation by probiotic E. coli strain decreases allergy incidence in high-risk children. In contrast to our expectation, proportion of Tregs has not been increased in probiotic supplemented children. Beneficial effect of probiotics on newborn immature immune system could be, at least partially, explained by the modulating immune function of Tregs. In summary, we detected increased proportion of Tregs in peripheral blood of allergic children, their functional properties were decreased in comparison with the Tregs of healthy children. A unifying hypothesis for these findings is that Treg numbers in allergic children are increased in order to compensate for decreased function.

Transcriptome Profiling of Human FoxP3+ Regulatory T Cells

PubMed Central

Bhairavabhotla, Ravikiran; Kim, Yong C.; Glass, Deborah D.; Escobar, Thelma M.; Patel, Mira C.; Zahr, Rami; Nguyen, Cuong K.; Kilaru, Gokhul K.; Muljo, Stefan A.; Shevach, Ethan M.

2015-01-01

The major goal of this study was to perform an in depth characterization of the “gene signature” of human FoxP3+ T regulatory cells (Tregs). Highly purified Tregs and T conventional cells (Tconvs) from multiple healthy donors (HD), either freshly explanted or activated in vitro, were analyzed via RNA sequencing (RNA-seq) and gene expression changes validated using the nCounter system. Additionally, we analyzed microRNA (miRNA) expression using TaqMan low-density arrays. Our results confirm previous studies demonstrating selective gene expression of FoxP3, IKZF2, and CTLA4 in Tregs. Notably, a number of yet uncharacterized genes (RTKN2, LAYN, UTS2, CSF2RB, TRIB1, F5, CECAM4, CD70, ENC1 and NKG7) were identified and validated as being differentially expressed in human Tregs. We further characterize the functional roles of RTKN2 and LAYN by analyzing their roles in vitro human Treg suppression assays by knocking them down in Tregs and overexpressing them in Tconvs. In order to facilitate a better understanding of the human Treg gene expression signature, we have generated from our results a hypothetical interactome of genes and miRNAs in Tregs and Tconvs, PMID:26686412

Expression of tyrosine hydroxylase in CD4+ T cells contributes to alleviation of Th17/Treg imbalance in collagen-induced arthritis.

PubMed

Wang, Xiao-Qin; Liu, Yan; Cai, Huan-Huan; Peng, Yu-Ping; Qiu, Yi-Hua

2016-12-01

Tyrosine hydroxylase (TH), a rate-limiting enzyme for the synthesis of catecholamines, is expressed in T lymphocytes. However, the role of T cell-expressed TH in rheumatoid arthritis (RA) is less clear. Herein, we aimed to show the contribution of TH expression by CD4 + T cells to alleviation of helper T (Th)17/regulatory T (Treg) imbalance in collagen-induced arthritis (CIA), a mouse model of RA. CIA was prepared by intradermal injection of collagen type II (CII) at tail base of DBA1/J mice. Expression of TH in the spleen and the ankle joints was measured by real-time polymerase chain reaction and Western blot analysis. Percentages of TH-expressing Th17 and Treg cells in splenic CD4 + T cells were determined by flow cytometry. Overexpression and knockdown of TH gene in CD4 + T cells were taken to evaluate effects of TH on Th17 and Treg cells in CIA. TH expression was upregulated in both the inflamed tissues (spleen and ankle joints) and the CD4 + T cells of CIA mice. In splenic CD4 + T cells, the cells expressing TH were increased during CIA. These cells that expressed more TH in CIA were mainly Th17 cells rather than Treg cells. TH gene overexpression in CD4 + T cells from CIA mice reduced Th17 cell percentage as well as Th17-related transcription factor and cytokine expression and secretion, whereas TH gene knockdown enhanced the Th17 cell activity. In contrast, TH gene overexpression increased Treg-related cytokine expression and secretion in CD4 + T cells of CIA mice, while TH gene knockdown decreased the Treg cell changes. Collectively, these findings show that CIA induces TH expression in CD4 + T cells, particularly in Th17 cells, and suggest that the increased TH expression during CIA represents an anti-inflammatory mechanism.

Diet and the anti-inflammatory effect of heat shock proteins.

PubMed

van Eden, Willem

2015-01-01

Stress proteins or heat shock proteins (HSPs) have a critical role in gut health and immune regulation. They have a functional significance as molecular chaperones for cell skeleton proteins and intercellular tight junction proteins. Herewith HSPs ensure gut epithelium integrity and effective intestinal barrier function. In addition, stress protein molecules such as HSP70 are a target for anti-inflammatory regulatory T cells (Tregs). Inflamed sites in the body feature inflammatory-stress induced enhanced levels of HSPs, which enable the immune system to target Tregs selectively to sites of inflammation. We have shown in experimental models of inflammatory diseases that both microbial HSP and endogenous (self) HSP molecules are capable of inducing the expansion of disease suppressive Tregs. Since the gut associated lymphoid tissue (GALT) is well poised towards the induction of regulation and tolerance, we set out to promote HSP expression and induction of Tregs in the gut lymphoid tissues by the oral administration of HSP co-inducing compounds. For the identification, selection and characterization of such compounds we have developed assay systems, such as reporter cell-lines, HSP specific T cell hybridomas and a transgenic mouse model (expression a HSP specific T cell receptor). The introduction of HSP coinducers into the diet constitutes a novel food based preventive or possibly even therapeutic approach in inflammatory diseases.

Forkhead box-P3+ regulatory T cells and toll-like receptor 2 co-expression in oral squamous cell carcinoma.

PubMed

Hussaini, H M; Parachuru, V P B; Seymour, G J; Rich, A M

2017-04-01

The function of forkhead box-P3 (FoxP3) regulatory T cells (Treg) and toll-like receptor (TLR)2 protein in the oral cancer microenvironment is not fully understood, but evidence from other malignancies suggests it is likely they are involved with tumour development and progression. The aim of this study was to investigate the distribution of FoxP3 + cells, TLR2 + cells and double-labelled FoxP3 + TLR2 + immune cells in oral squamous cell carcinoma (OSCC), using immunohistochemistry (IHC) and immunofluorescence (IF). 25 archival cases of OSCC were immunostained with anti-FoxP3 and anti-TLR2 antibodies. Inflamed hyperplastic oral mucosal tissues were used as controls. The proportion of single-labelled, double-labelled and negative cells was determined. A higher frequency of double-labelled FoxP3 + TLR2 + Tregs was observed within the immune cells of OSCC compared to inflamed controls using IHC (p<0.05). Cell-to-cell contact between single-stained TLR2 + cells and FoxP3 + cells was noted. Double IF studies validated demonstration of co-expression of FoxP3 + /TLR2 + immune cells in OSCC. The presence of FoxP3 + TLR2 + cells within the OSCC microenvironment may represent a dendritic cell-dependent pathway capable of inhibiting Treg suppressive activity, potentially enhancing the anti-tumour response. Modulation of TLR2-Treg interactions should be further explored to determine if they have a role in the therapeutic management of OSCC. Copyright © 2017 Elsevier GmbH. All rights reserved.

Association of Regulatory T Cells with Diabetes Type-1 and Its Renal and Vascular Complications Based on the Expression of Forkhead Box Protein P3 (FoxP3), Helios and Neurophilin-1.

PubMed

Khamechian, Tahereh; Irandoust, Behnaz; Mohammadi, Hanieh; Nikoueinejad, Hassan; Akbari, Hossein

2018-04-01

In recent years, it has been recognized that regulatory T cells (Tregs) play a critical role in maintaining immune tolerance. Moreover, the expression of two markers named Helios and neurophilin-1 (NRP-1) has been highlighted in such cells. Helios, an intracellular transcription marker, largely differentiates twomost operative sub group of Tregs, namely naturally occurring (nTreg) and induced (iTreg) Tregs, and NRP-1 is reckoned as a membranous activity marker of Tregs. We aimed to count peripheral mononuclear cells expressing such markers in a group of type 1 diabetes patients to elucidate the possible role of Tregs in the pathogenesis of such disease and its complications. Blood samples from 61 adult patients with type 1 diabetes and 61 sex and age-matched healthy controls were tested to count two types of Tregs, namely naturally occurring and inducible types, according to the expression of cell surface markers of CD4/CD25/CD47-FITC/PE/APC and intracellular markers of FoxP3/Helios-PE-CY5/eFlour450 by flow cytometry, respectively.We also investigated the relation between expression of such markers with HbA1c, urine albumin/creatinine ratio (UACR), and common carotid intima thickness (CIMT). The circulatory frequency of both Helios+ and Helios- T-cells were significantly decreased in patients compared to those in healthy controls (p<0.001). There was also a significant decrease in circulatory frequency of Helios+ NRP-1+ and Helios- NRP-1+ cells in the patients compared to controls (p=0.029). According to expression of Helios and NRP-1 markers, the number and function of both Tregs were decreased in diabetic patients. Moreover, the neurophilin expression was inversely associated with complications of type 1 diabetes.

Cloning and expression of canine CD25 for validation of an anti-human CD25 antibody to compare T regulatory lymphocytes in healthy dogs and dogs with osteosarcoma.

PubMed

Rissetto, K C; Rindt, H; Selting, K A; Villamil, J A; Henry, C J; Reinero, C R

2010-05-15

T regulatory cells (Tregs) are a unique subset of T helper cells that serve to modify/inhibit effector cells of the immune system and thus are essential to prevent autoimmunity. Overzealous Treg activity may contribute to impaired immune responses to cancer. Tregs can be phenotypically identified by proteins expressed on the cell surface (CD4 and CD25) and inside the cell (forkhead box3 (FoxP3)), although in dogs, no anti-canine CD25 antibody exists. We hypothesized that a mouse anti-human CD25 antibody definitively recognizes the canine protein and can be used to identify Tregs in dogs. We describe cloning and transfection of the canine CD25 gene into human HeLa cells with subsequent expression of the canine protein on the cell surface detected using an anti-human CD25 antibody in a flow cytometric assay. Validation of this antibody was used to identify CD4+CD25+FoxP3+ Tregs in 39 healthy dogs and 16 dogs with osteosarcoma (OSA). Results were expressed in five different ways and showed significantly fewer %CD4+CD25+ T lymphocytes expressing FoxP3 in blood of older dogs (>/=7 years) compared with the other two age groups (<2 and 2-6 years) (p<0.001) and fewer %CD4+CD25+FoxP3+ Tregs in the tumor draining lymph nodes of OSA patients compared to the unrelated lymph node (p=0.049). However, there was no significant difference in % Tregs in the peripheral blood or lymph nodes between the control dogs and those with OSA. While the CD25 antibody can be successfully used in a flow cytometric assay to identify Tregs, this study does not support clinical utility of phenotypic recognition of Tregs in dogs with OSA. Copyright 2010 Elsevier B.V. All rights reserved.

In Situ Detection of Regulatory T Cells in Human Genital Herpes Simplex Virus Type 2 (HSV-2) Reactivation and Their Influence on Spontaneous HSV-2 Reactivation

PubMed Central

Milman, Neta; Zhu, Jia; Johnston, Christine; Cheng, Anqi; Magaret, Amalia; Koelle, David M.; Huang, Meei-Li; Jin, Lei; Klock, Alexis; Layton, Erik D.; Corey, Lawrence

2016-01-01

Background. Herpes simplex virus type 2 (HSV-2) reactivation is accompanied by a sustained influx of CD4+ and CD8+ T cells that persist in genital tissue for extended periods. While CD4+ T cells have long been recognized as being present in herpetic ulcerations, their role in subclinical reactivation and persistence is less well known, especially the role of CD4+ regulatory T cells (Tregs). Methods. We characterized the Treg (CD4+Foxp3+) population during human HSV-2 reactivation in situ in sequential genital skin biopsy specimens obtained from HSV-2–seropositive subjects at the time of lesion onset up to 8 weeks after healing. Results. High numbers of Tregs infiltrated to the site of viral reactivation and persisted in proximity to conventional CD4+ T cells (Tconvs) and CD8+ T cells. Treg density peaked during the lesion stage of the reactivation. The number of Tregs from all time points (lesion, healed, 2 weeks after healing, 4 weeks after healing, and 8 weeks after healing) was significantly higher than in control biopsy specimens from unaffected skin. There was a direct correlation between HSV-2 titer and Treg density. Conclusions. The association of a high Treg to Tconv ratio with high viral shedding suggests that the balance between regulatory and effector T cells influences human HSV-2 disease. PMID:27117511

Deletion of Fibrinogen-like Protein 2 (FGL-2), a Novel CD4+ CD25+ Treg Effector Molecule, Leads to Improved Control of Echinococcus multilocularis Infection in Mice

PubMed Central

Wang, Junhua; Vuitton, Dominique A.; Müller, Norbert; Hemphill, Andrew; Spiliotis, Markus; Blagosklonov, Oleg; Grandgirard, Denis; Leib, Stephen L.; Shalev, Itay; Levy, Gary; Lu, Xiaomei; Lin, Renyong; Wen, Hao; Gottstein, Bruno

2015-01-01

Background The growth potential of the tumor-like Echinococcus multilocularis metacestode (causing alveolar echinococcosis, AE) is directly linked to the nature/function of the periparasitic host immune-mediated processes. We previously showed that Fibrinogen-like-protein 2 (FGL2), a novel CD4+CD25+ Treg effector molecule, was over-expressed in the liver of mice experimentally infected with E. multilocularis. However, little is known about its contribution to the control of this chronic helminth infection. Methods/Findings Key parameters for infection outcome in E. multilocularis-infected fgl2-/- (AE-fgl2-/-) and wild type (AE-WT) mice at 1 and 4 month(s) post-infection were (i) parasite load (i. e. wet weight of parasitic metacestode tissue), and (ii) parasite cell proliferation as assessed by determining E. multilocularis 14-3-3 gene expression levels. Serum FGL2 levels were measured by ELISA. Spleen cells cultured with ConA for 48h or with E. multilocularis Vesicle Fluid (VF) for 96h were analyzed ex-vivo and in-vitro. In addition, spleen cells from non-infected WT mice were cultured with rFGL2/anti-FGL2 or rIL-17A/anti-IL-17A for further functional studies. For Treg-immune-suppression-assays, purified CD4+CD25+ Treg suspensions were incubated with CD4+ effector T cells in the presence of ConA and irradiated spleen cells as APCs. Flow cytometry and qRT-PCR were used to assess Treg, Th17-, Th1-, Th2-type immune responses and maturation of dendritic cells. We showed that AE-fgl2-/- mice exhibited (as compared to AE-WT-animals) (a) a significantly lower parasite load with reduced proliferation activity, (b) an increased T cell proliferative response to ConA, (c) reduced Treg numbers and function, and (d) a persistent capacity of Th1 polarization and DC maturation. Conclusions FGL2 appears as one of the key players in immune regulatory processes favoring metacestode survival by promoting Treg cell activity and IL-17A production that contributes to FGL2-regulation. Prospectively, targeting FGL2 could be an option to develop an immunotherapy against AE and other chronic parasitic diseases. PMID:25955764

Association between discordant immunological response to highly active anti-retroviral therapy, regulatory T cell percentage, immune cell activation and very low-level viraemia in HIV-infected patients.

PubMed

Saison, J; Ferry, T; Demaret, J; Maucort Boulch, D; Venet, F; Perpoint, T; Ader, F; Icard, V; Chidiac, C; Monneret, G

2014-06-01

The mechanisms sustaining the absence of complete immune recovery in HIV-infected patients upon long-term effective highly active anti-retroviral therapy (HAART) remain elusive. Immune activation, regulatory T cells (T(regs)) or very low-level viraemia (VLLV) have been alternatively suspected, but rarely investigated simultaneously. We performed a cross-sectional study in HIV-infected aviraemic subjects (mean duration of HAART: 12 years) to concomitantly assess parameters associated independently with inadequate immunological response. Patients were classified as complete immunological responders (cIR, n = 48) and inadequate immunological responders (iIR, n = 39), depending on the CD4(+) T cell count (> or < 500/mm(3)). Clinical and virological data (including very low-level viraemia) were collected. In parallel, immunophenotyping of CD4(+) lymphocytes, including T(reg) subsets, and CD8(+) T cells was performed. Percentages of activated CD4(+) T cells, T(regs), effector T(regs) and terminal effector T(regs) were found to be significantly elevated in iIR. Neither the percentage of activated CD8(+) T cells nor VLLV were found to be associated with iIR. In the multivariate analysis, nadir of CD4(+) T cell count and percentage of T(regs) were the only two parameters associated independently with iIR [odds ratio (OR) = 2·339, P = 0·001, and OR = 0·803, P = 0·041]. We present here the largest study investigating simultaneously the immune response to long-term HAART, activation of CD4(+) and CD8(+) T cells, T(reg) percentages and very low-level viraemia. Causative interactions between T(regs) and CD4(+) T cells should now be explored prospectively in a large patients cohort. © 2014 British Society for Immunology.

FOXP3 Expression in GARP-Transduced Helper T Cells Is Not Associated with FOXP3 TSDR Demethylation

PubMed Central

Kehrmann, Jan; Zeschnigk, Michael; Buer, Jan; Probst-Kepper, Michael

2011-01-01

Aim: Glycoprotein A repetitions predominant (GARP or LRRC32) represents a human regulatory CD4+ CD25hi FOXP3+ T (Treg) cell-specific receptor that controls FOXP3. Ectopic expression of GARP in helper T (Th) cells has been shown to be sufficient for the induction of FOXP3 and generation of a stable regulatory phenotype. Since expression of FOXP3 in Treg cells is epigenetically controlled by a conserved motif, the so-called Treg-specific demethylated region (TSDR), we asked whether GARP-mediated upregulation of FOXP3 in Th cells is similarly accompanied by demethylation of the TSDR. Methods: DNA methylation of the FOXP3 TSDR was analyzed by direct sequencing of polymerase chain reaction (PCR) products from bisulfite-treated genomic DNA. Results: Although GARP-transduced Th cells exhibit constitutive FOXP3 expression and a regulatory phenotype, the FOXP3 TSDR is completely methylated as in naive Th cells. GARP-mediated FOXP3 upregulation in Th cells is not associated with Treg-specific demethylation of the FOXP3 TSDR. Conclusion: Although GARP-engineered Th cells exhibit stable FOXP3 expression and a phenotypic reprogramming towards Treg cells in vitro, these cells do not completely mimic the epigenotype of natural Treg cells. Thus, concepts based on the genetic modification of Th cells as cellular therapies to treat autoimmune diseases or to control transplantation tolerance should be critically tested before any clinical application. PMID:22670117

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

PubMed

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.

TGF-β: the sword, the wand, and the shield of FOXP3(+) regulatory T cells.

PubMed

Tran, Dat Q

2012-02-01

Since its rediscovery in the mid-1990s, FOXP3(+) regulatory T cells (Tregs) have climbed the rank to become commander-in-chief of the immune system. They possess diverse power and ability to orchestrate the immune system in time of inflammation and infection as well as in time of harmony and homeostasis. To be the commander-in-chief, they must be equipped with both offensive and defensive weaponry. This review will focus on the function of transforming growth factor-β (TGF-β) as the sword, the wand, and the shield of Tregs. Functioning as a sword, this review will begin with a discussion of the evidence that supports how Tregs utilize TGF-β to paralyze cell activation and differentiation to suppress immune response. It will next provide evidence on how TGF-β from Tregs acts as a wand to convert naïve T cells into iTregs and Th17 to aid in their combat against inflammation and infection. Lastly, the review will present evidence on the role of TGF-β produced by Tregs in providing a shield to protect and maintain Tregs against apoptosis and destabilization when surrounded by inflammation and constant stimulation. This triadic function of TGF-β empowers Tregs with the responsibility and burden to maintain homeostasis, promote immune tolerance, and regulate host defense against foreign pathogens.

Galectin-9-CD44 interaction enhances stability and function of adaptive regulatory T cells | Center for Cancer Research

Cancer.gov

The β-galactoside-binding protein galectin-9 is critical in regulating the immune response, but the mechanism by which it functions remains unclear. We have demonstrated that galectin-9 is highly expressed by induced regulatory T cells (iTreg) and was crucial for the generation and function of iTreg cells, but not natural regulatory T (nTreg) cells. Galectin-9 expression

Rebamipide suppresses collagen-induced arthritis through reciprocal regulation of th17/treg cell differentiation and heme oxygenase 1 induction.

PubMed

Moon, Su-Jin; Park, Jin-Sil; Woo, Yun-Ju; Lim, Mi-Ae; Kim, Sung-Min; Lee, Seon-Yeong; Kim, Eun-Kyung; Lee, Hee Jin; Lee, Weon Sun; Park, Sang-Hi; Jeong, Jeong-Hee; Park, Sung-Hwan; Kim, Ho-Youn; Cho, Mi-La; Min, Jun-Ki

2014-04-01

Rebamipide, a gastroprotective agent, has the ability to scavenge reactive oxygen radicals. Increased oxidative stress is implicated in the pathogenesis of rheumatoid arthritis (RA). We undertook this study to investigate the impact of rebamipide on the development of arthritis and the pathophysiologic mechanisms by which rebamipide attenuates arthritis severity in a murine model of RA. Collagen-induced arthritis (CIA) was induced in DBA/1J mice. Anti-type II collagen antibody titers and interleukin-17 (IL-17) levels were determined using enzyme-linked immunosorbent assay. The expression of transcription factors was analyzed by immunostaining and Western blotting. Frequencies of IL-17-producing CD4+ T cells (Th17 cells) and CD4+CD25+FoxP3+ Treg cells were analyzed by flow cytometry. Rebamipide reduced the clinical arthritis score and severity of histologic inflammation and cartilage destruction in a dose-dependent manner. The joints isolated from rebamipide-treated mice with CIA showed decreased expression of nitrotyrosine, an oxidative stress marker. Rebamipide-treated mice showed lower circulating levels of type II collagen-specific IgG, IgG1, and IgG2a. Whereas the number of Th17 cells in spleens was decreased in rebamipide-treated mice with CIA, a significant increase in the number of Treg cells in spleens was observed. In vitro, rebamipide inhibited Th17 cell differentiation through STAT-3/retinoic acid receptor-related orphan nuclear receptor γt and reciprocally induced Treg cell differentiation through FoxP3. Rebamipide increased Nrf2 nuclear activities in murine CD4+ T cells and LBRM-33 murine T lymphoma cells. Heme oxygenase 1 (HO-1) expression in the spleens was markedly increased in rebamipide-treated mice. The inhibitory effects of rebamipide on joint inflammation are associated with recovery from an imbalance between Th17 cells and Treg cells and with activation of an Nrf2/HO-1 antioxidant pathway. Copyright © 2014 by the American College of Rheumatology.

Ocular allergy modulation to hi-dose antigen sensitization is a Treg-dependent process.

PubMed

Lee, Hyun Soo; Schlereth, Simona; Khandelwal, Payal; Saban, Daniel R

2013-01-01

A reproducible method to inhibit allergic immune responses is accomplished with hi-dose Ag sensitization, via intraperitoneal (IP) injection. However, the role of CD4+ CD25+ FoxP3+ T regulatory cells (Treg) in this process is unknown, as is whether such modulation extends to ocular allergy. We therefore determined herein whether hi-dose sensitization modulates ocular allergy, and whether CD4+ CD25+ FoxP3+ Treg are involved. C57BL/6 mice were IP sensitized via low-dose (100 µg) versus hi-dose (1000 µg) ovalbumin (OVA), in aluminum hydroxide (1 mg) and pertussis-toxin (300 ng). Other mice received anti-CD25 Ab (PC61) to ablate Treg during sensitization. In another experiment, Treg from hi-dose sensitized mice were adoptively transferred into low-dose sensitized mice. Once daily OVA challenges were administered. Clinical signs, IgE, T cell cytokines, and eosinophils were assessed. Data revealed that hi-dose, but not low-dose, sensitization led to allergy modulation, indicated by decreased clinical signs, serum IgE levels, Th2 recall responses, and eosinophil recruitment. T cells from hi-dose sensitized mice showed a robust increase in TGF-b production, and Treg from these mice were able to efficiently suppress effector T cell proliferation in vitro. In addition, in vivo Treg ablation in hi-dose sensitized mice revoked allergy modulation. Lastly, Treg from hi-dose sensitized mice were able to adoptively transfer allergy modulation to their low-dose sensitized counterparts. Collectively, these findings indicate that modulation to hi-dose sensitization, which is extended to ocular allergy, occurs in a Treg-dependent manner. In addition, our data suggest that hi-dose sensitization may henceforth facilitate the further examination of CD4+ CD25+ FoxP3+ Treg in allergic disease.

Phenotypic Alterations Involved in CD8+ Treg Impairment in Systemic Sclerosis

PubMed Central

Negrini, Simone; Fenoglio, Daniela; Parodi, Alessia; Kalli, Francesca; Battaglia, Florinda; Nasi, Giorgia; Curto, Monica; Tardito, Samuele; Ferrera, Francesca; Filaci, Gilberto

2017-01-01

Systemic sclerosis (SSc) is a connective tissue disease characterized by tissue fibrosis, vasculopathy, and autoimmunity. Although the exact pathogenetic mechanisms behind SSc remain to be fully elucidated, a great deal of evidence suggests the existence of an unbalanced ratio between the effector and regulatory arms of the immune system. With regard to the T regulatory (Treg) compartment, we observed that CD8+ Treg subsets display functional defects in SSc-affected patients. Since CD127 down-modulation and CD39 upregulation have been observed on Treg subsets, the phenotypic expression of these molecules was analyzed on the CD8+CD28− Treg precursors and on CD8+ Treg cells generated in vitro through interleukin-10 commitment. Immunophenotypic data from SSc patients were compared to those obtained from healthy subjects. The analyses performed on ex vivo-isolated CD8+CD28− Treg precursors did not show any significant differences in CD39 or CD127 expression as compared to values obtained from healthy donors. On the contrary, in vitro-generated CD8+ Tregs obtained from SSc patients displayed reduced expression of the CD39 molecule as compared to controls. Moreover, the percentage of CD127+ cells was significantly higher in in vitro-generated CD8+ Tregs from SSc patients compared to CD8+ Tregs obtained from healthy donors. Taken together, these findings may indicate an impairment of maturation processes affecting CD8+ Treg cells in SSc patients. This impairment of maturation involves phenotypic alterations that are mainly characterized by a deficient CD39 upregulation and a lack of down-modulation of the CD127 molecule. PMID:28154567

Reciprocity between Regulatory T Cells and Th17 Cells: Relevance to Polarized Immunity in Leprosy

PubMed Central

Sadhu, Soumi; Khaitan, Binod Kumar; Joshi, Beenu; Sengupta, Utpal; Nautiyal, Arvind Kumar; Mitra, Dipendra Kumar

2016-01-01

T cell defect is a common feature in lepromatous or borderline lepromatous leprosy (LL/BL) patients in contrast to tuberculoid or borderline tuberculoid type (TT/BT) patients. Tuberculoid leprosy is characterized by strong Th1-type cell response with localized lesions whereas lepromatous leprosy is hallmarked by its selective Mycobacterium leprae specific T cell anergy leading to disseminated and progressive disease. FoxP3+ Regulatory T cells (Treg) which are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases also dampen proinflammatory T cells that include T helper 17 (Th17) cells. This study is aimed at evaluating the role of Treg cells in influencing other effector T cells and its relationship with the cytokine polarized state in leprosy patients. Peripheral blood mononuclear cells from of BT/TT (n = 15) and BL/LL (n = 15) patients were stimulated with M. leprae antigen (WCL) in presence of golgi transport inhibitor monensin for FACS based intracellular cytokine estimation. The frequency of Treg cells showed >5-fold increase in BL/LL in comparison to BT/TT and healthy contacts. These cells produced suppressive cytokine, IL-10 in BL/LL as opposed to BT/TT (p = 0.0200) indicating their suppressive function. The frequency of Th17 cells (CD4, CD45RO, IL-17) was, however, higher in BT/TT. Significant negative correlation (r = -0.68, P = 0.03) was also found between IL-10 of Treg cells and IL-17+ T cells in BL/LL. Blocking IL-10/TGF-β restored the IL-17+ T cells in BL/LL patients. Simultaneously, presence of Th17 related cytokines (TGF-β, IL-6, IL-17 and IL-23) decreased the number of FoxP3+ Treg cells concomitantly increasing IL-17 producing CD4+ cells in lepromatous leprosy. Higher frequency of Programmed Death-1/PD-1+ Treg cells and its ligand, PDL-1 in antigen presenting cells (APCs) was found in BL/LL patients. Inhibition of this pathway led to rescue of IFN-γ and IL-17 producing T cells. Results indicate that Treg cells are largely responsible for the kind of immunosuppression observed in BL/LL patients. This study also proves that Treg cells are profoundly affected by the cytokine milieu and this property may be utilized for benefit of the host. PMID:26751584

The relation between FoxP3⁺ regulatory T cells and fungal density in oral paracoccidioidomycosis: a preliminary study.

PubMed

Cardoso, Rhanderson Miller Nascimento; Jham, Bruno Correia; do Carmo, Gabriela Mota; Batista, Aline Carvalho; de Oliveira, Flávia Aparecida; de Paula, Elbio Candido; Mesquita, Ricardo Alves; da Silva, Tarcília Aparecida; Duarte, Eliza Carla Barroso

2014-12-01

Regulatory T (Treg) cells may play an important role in the pathogenesis of paracoccidioidomycosis (PCM), but data on the role of Treg cells in the context of oral PCM are still scarce. The objectives of this study were to investigate the density of FoxP3(+) T regulatory cells in oral PCM and to correlate the results with the density of Paracoccidioides brasiliensis in the lesions. Cases of chronic oral PCM seen between 2000 and 2008 were included in this study. The diagnosis of all lesions was confirmed with histopathological examination and Grocott-Gomori staining. The quantitative analysis of the viable fungi was conducted in all cases with Grocott-stained slides. Treg cells were identified using antibodies against FoxP3. Pearson correlation coefficient was used to test the correlation between the density of fungi and Treg cells. Results were considered significant when P < 0.05. A total of 11 cases of oral PCM were obtained. There was a positive correlation between fungal density and FoxP3(+) Treg cells density in oral lesions, however, without statistical significance. A positive relation between Treg cells and fungal density was seen in oral PCM. Further studies are required to further elucidate the role of these cells in the pathogenesis of oral PCM, as well the clinical significance of these findings. © 2014 Blackwell Verlag GmbH.

Leptin levels in patients with systemic lupus erythematosus inversely correlate with regulatory T cell frequency.

PubMed

Wang, X; Qiao, Y; Yang, L; Song, S; Han, Y; Tian, Y; Ding, M; Jin, H; Shao, F; Liu, A

2017-11-01

Leptin levels are increased in patients with systemic lupus erythematosus (SLE) but little is known on how this correlates with several disease characteristics including the frequency of regulatory T cells (Tregs). Here we compared serum leptin levels with frequency of circulating Tregs in 47 lupus patients vs. 25 healthy matched controls. Correlations with lupus disease activity were also analyzed, as well as Treg proliferation potential. It was found that leptin was remarkably increased in SLE patients as compared to controls, particularly in SLE patients with moderate and severe active SLE, and the increase correlated with disease activity. Importantly, increased leptin in lupus patients inversely correlated with the frequency of Tregs but not in controls, and leptin neutralization resulted in the expansion of Tregs ex vivo. Thus, hyperleptinemia in lupus patients correlates directly with disease activity and inversely with Treg frequency. The finding that leptin inhibition expands Tregs in SLE suggests possible inhibition of this molecule for an enhanced Treg function in the disease.

Innovative Strategies for Breast Cancer Immunotherapy

DTIC Science & Technology

2014-09-01

as well as T regulatory cells ( Tregs : FOXP3 and CD25 positive) were determined in K-CAR T cells obtained from BC patients or normal female donors...since Tregs are a component of the immune system that suppresses immune responses of other cells. A sample from a BC patient (#243, diagnosed with...33). Suppression of CD8+ effector cells by CD4+CD25+FoxP3+ regulatory T cells ( Tregs ) plays a key role in this immunosuppression (34). Our results

Forced LIGHT expression in prostate tumors overcomes Treg mediated immunosuppression and synergizes with a prostate tumor therapeutic vaccine by recruiting effector T lymphocytes

PubMed Central

Yan, Lisa; Da Silva, Diane M.; Verma, Bhavna; Gray, Andrew; Brand, Heike E.; Skeate, Joseph G.; Porras, Tania B.; Kanodia, Shreya; Kast, W. Martin

2014-01-01

Background LIGHT, a ligand for lymphotoxin-β receptor (LTβR) and herpes virus entry mediator, is predominantly expressed on activated immune cells and LTβR signaling leads to the recruitment of lymphocytes. The interaction between LIGHT and LTβR has been previously shown in a virus induced tumor model to activate immune cells and result in tumor regression, but the role of LIGHT in tumor immunosuppression or in a prostate cancer setting, where self antigens exist, has not been explored. We hypothesized that forced expression of LIGHT in prostate tumors would shift the pattern of immune cell infiltration, would inhibit T regulatory cells (Tregs) and would induce prostate cancer tumor associated antigen (TAA) specific T cells that would eradicate tumors. Methods Real Time PCR was used to evaluate expression of forced LIGHT and various other genes in prostate tumors samples. Adenovirus encoding murine LIGHT was injected intratumorally into TRAMP C2 prostate cancer cell tumor bearing mice for in vivo studies. Chemokine and cytokine concentrations were determined by multiplex ELISA. Flow cytometry was used to phenotype tumor infiltrating lymphocytes and expression of LIGHT on the tumor cell surface. Tumor specific lymphocytes were quantified via an ELISpot assay. Treg induction and Treg suppression assays determined Treg functionality after LIGHT treatment. Results LIGHT expression peaked within 48 hours of infection, recruited effector T cells into the tumor microenvironment that recognized mouse prostate stem cell antigen (PSCA) and inhibited the infiltration of Tregs. Tregs isolated from tumor draining lymph nodes had impaired suppressive capability after LIGHT treatment. LIGHT in combination with a therapeutic vaccine, PSCA TriVax, reduced tumor burden. Conclusion Forced LIGHT treatment combined with PSCA TriVax therapeutic vaccination delays prostate cancer progression in mice by recruiting effector T lymphocytes to the tumor and inhibiting Treg mediated immunosuppression. PMID:25399517

Forced LIGHT expression in prostate tumors overcomes Treg mediated immunosuppression and synergizes with a prostate tumor therapeutic vaccine by recruiting effector T lymphocytes.

PubMed

Yan, Lisa; Da Silva, Diane M; Verma, Bhavna; Gray, Andrew; Brand, Heike E; Skeate, Joseph G; Porras, Tania B; Kanodia, Shreya; Kast, W Martin

2015-02-15

LIGHT, a ligand for lymphotoxin-β receptor (LTβR) and herpes virus entry mediator, is predominantly expressed on activated immune cells and LTβR signaling leads to the recruitment of lymphocytes. The interaction between LIGHT and LTβR has been previously shown to activate immune cells and result in tumor regression in a virally-induced tumor model, but the role of LIGHT in tumor immunosuppression or in a prostate cancer setting, where self antigens exist, has not been explored. We hypothesized that forced expression of LIGHT in prostate tumors would shift the pattern of immune cell infiltration toward an anti-tumoral milieu, would inhibit T regulatory cells (Tregs) and would induce prostate cancer tumor associated antigen (TAA) specific T cells that would eradicate tumors. Real Time PCR was used to evaluate expression of forced LIGHT and other immunoregulatory genes in prostate tumors samples. For in vivo studies, adenovirus encoding murine LIGHT was injected intratumorally into TRAMP-C2 prostate cancer cell tumor bearing mice. Chemokine and cytokine concentrations were determined by multiplex ELISA. Flow cytometry was used to phenotype tumor infiltrating lymphocytes and expression of LIGHT on the tumor cell surface. Tumor-specific lymphocytes were quantified via ELISpot assay. Treg induction and Treg suppression assays determined Treg functionality after LIGHT treatment. LIGHT in combination with a therapeutic vaccine, PSCA TriVax, reduced tumor burden. LIGHT expression peaked within 48 hr of infection, recruited effector T cells that recognized mouse prostate stem cell antigen (PSCA) into the tumor microenvironment, and inhibited infiltration of Tregs. Tregs isolated from tumor draining lymph nodes had impaired suppressive capability after LIGHT treatment. Forced LIGHT treatment combined with PSCA TriVax therapeutic vaccination delays prostate cancer progression in mice by recruiting effector T lymphocytes to the tumor and inhibiting Treg mediated immunosuppression. Prostate 75:280-291, 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Epirubicin, Identified Using a Novel Luciferase Reporter Assay for Foxp3 Inhibitors, Inhibits Regulatory T Cell Activity.

PubMed

Kashima, Hajime; Momose, Fumiyasu; Umehara, Hiroshi; Miyoshi, Nao; Ogo, Naohisa; Muraoka, Daisuke; Shiku, Hiroshi; Harada, Naozumi; Asai, Akira

2016-01-01

Forkhead box protein p3 (Foxp3) is crucial to the development and suppressor function of regulatory T cells (Tregs) that have a significant role in tumor-associated immune suppression. Development of small molecule inhibitors of Foxp3 function is therefore considered a promising strategy to enhance anti-tumor immunity. In this study, we developed a novel cell-based assay system in which the NF-κB luciferase reporter signal is suppressed by the co-expressed Foxp3 protein. Using this system, we screened our chemical library consisting of approximately 2,100 compounds and discovered that a cancer chemotherapeutic drug epirubicin restored the Foxp3-inhibited NF-κB activity in a concentration-dependent manner without influencing cell viability. Using immunoprecipitation assay in a Treg-like cell line Karpas-299, we found that epirubicin inhibited the interaction between Foxp3 and p65. In addition, epirubicin inhibited the suppressor function of murine Tregs and thereby improved effector T cell stimulation in vitro. Administration of low dose epirubicin into tumor-bearing mice modulated the function of immune cells at the tumor site and promoted their IFN-γ production without direct cytotoxicity. In summary, we identified the novel action of epirubicin as a Foxp3 inhibitor using a newly established luciferase-based cellular screen. Our work also demonstrated our screen system is useful in accelerating discovery of Foxp3 inhibitors.

Single-cell dynamics of mast cell-CD4+ CD25+ regulatory T cell interactions.

PubMed

Frossi, Barbara; D'Incà, Federica; Crivellato, Enrico; Sibilano, Riccardo; Gri, Giorgia; Mongillo, Marco; Danelli, Luca; Maggi, Laura; Pucillo, Carlo E

2011-07-01

The biological behavior of immune cells is determined by their intrinsic properties and interactions with other cell populations within their microenvironment. Several studies have confirmed the existence of tight spatial interactions between mast cells (MCs) and Tregs in different settings. For instance, we have recently identified the functional cross-talk between MCs and Tregs, through the OX40L-OX40 axis, as a new mechanism of reciprocal influence. However, there is scant information regarding the single-cell dynamics of this process. In this study, time-lapse video microscopy revealed direct interactions between Tregs and MCs in both murine and human cell co-cultures, resulting in the inhibition of the MC degranulation response. MCs incubated with WT, but not OX40-deficient, Tregs mediated numerous and long-lasting interactions and displayed different morphological features lacking the classical signs of exocytosis. MC degranulation and Ca2+ mobilization upon activation were inhibited by Tregs on a single-cell basis, without affecting overall cytokine secretion. Transmission electron microscopy showed ultrastructural evidence of vesicle-mediated secretion reconcilable with the morphological pattern of piecemeal degranulation. Our results suggest that MC morphological and functional changes following MC-Treg interactions can be ascribed to cell-cell contact and represent a transversal, non-species-specific mechanism of immune response regulation. Further research, looking at the molecular composition of this interaction will broaden our understanding of its contribution to immunity. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

PubMed

Geng, Shuang; Yu, Yang; Kang, Youmin; Pavlakis, George; Jin, Huali; Li, Jinyao; Hu, Yanxin; Hu, Weibin; Wang, Shuang; Wang, Bin

2011-05-05

We previously showed that co-immunization with a protein antigen and a DNA vaccine coding for the same antigen induces CD40 low IL-10 high tolerogenic DCs, which in turn stimulates the expansion of antigen-specific CD4+CD25-Foxp3+ regulatory T cells (CD25- iTreg). However, it was unclear how to choose the antigen sequence to maximize tolerogenic antigen presentation and, consequently, CD25- iTreg induction. In the present study, we demonstrated the requirement of highly antigenic epitopes for CD25- iTreg induction. Firstly, we showed that the induction of CD25- iTreg by tolerogenic DC can be blocked by anti-MHC-II antibody. Next, both the number and the suppressive activity of CD25- iTreg correlated positively with the overt antigenicity of an epitope to activate T cells. Finally, in a mouse model of dermatitis, highly antigenic epitopes derived from a flea allergen not only induced more CD25- iTreg, but also more effectively prevented allergenic reaction to the allergen than did weakly antigenic epitopes. Our data thus indicate that efficient induction of CD25- iTreg requires highly antigenic peptide epitopes. This finding suggests that highly antigenic epitopes should be used for efficient induction of CD25- iTreg for clinical applications such as flea allergic dermatitis.

Regulatory T Cells in Peripheral Blood and Cerebrospinal Fluid of Syphilis Patients with and without Neurological Involvement

PubMed Central

Li, Kang; Wang, Cuini; Lu, Haikong; Gu, Xin; Guan, Zhifang; Zhou, Pingyu

2013-01-01

Background Syphilis, a sexually transmitted disease caused by spirochetal bacterium Treponema pallidum, can progress to affect the central nervous system, causing neurosyphilis. Accumulating evidence suggest that regulatory T cells (Tregs) may play an important role in the pathogenesis of syphilis. However, little is known about Treg response in neurosyphilis. Methodology/Principal Findings We analyzed Treg frequencies and Transforming Growth Factor-β (TGF-β) levels in the blood and CSF of 431 syphilis patients without neurological involvement, 100 neurosyphilis patients and 100 healthy donors. Suppressive function of Tregs in peripheral blood was also assessed. Among syphilis patients without neurological involvement, we found that secondary and serofast patients had increased Treg percentages, suppressive function and TGF-β levels in peripheral blood compared to healthy donors. Serum Rapid Plasma Reagin (RPR) titers were positively correlated with Treg numbers in these patients. Compared to these syphilis patients without neurological involvement, neurosyphilis patients had higher Treg frequency in peripheral blood. In the central nervous system, neurosyphilis patients had higher numbers of leukocytes in CSF compared to syphilis patients without neurological involvement. CD4+ T cells were the predominant cell type in the inflammatory infiltrates in CSF of neurosyphilis patients. Interestingly, among these neurosyphilis patients, a significant decrease in CSF CD4+ CD25high Treg percentage and number was observed in symptomatic neurosyphilis patients compared to those of asymptomatic neurosyphilis patients, which may be associated with low CSF TGF-β levels. Conclusions Our findings suggest that Tregs might play an important role in both bacterial persistence and neurologic compromise in the pathogenesis of syphilis. PMID:24244772

Regulatory and activated effector T cells in chronic hepatitis C virus: Relation to autoimmunity

PubMed Central

Fouad, Hanan; El Raziky, Maissa; Hassan, Eman Medhat; Aziz, Ghada Mahmoud Abdel; Darweesh, Samar K; Sayed, Ahmed Reda

2016-01-01

AIM To investigate how Tregs are regulated in chronic hepatitis C virus (HCV) patients via assessment of Tregs markers (granzyme 2, CD69 and FoxP3), Teffs markers [TNFRSF4 (OX40), INFG] and CD4, CD25 genes. METHODS A prospective study was conducted on 120 subjects divided into 4 groups: Group I (n = 30) treatment naïve chronic HCV patients; Group II (n = 30) chronic HCV treated with Peg/Riba; Group III (n = 30) chronic HCV associated with non-organ specific autoantibody and Group IV (n = 30) healthy persons as a control group. Tregs and Teffs markers were assessed in peripheral blood mononuclear cells by quantitative real time reverse transcriptase-polymerase chain reaction. RESULTS Chronic HCV patients exhibited significant higher levels of both Teffs and Tregs in comparison to healthy control group. Tregs markers were significantly decreased in Peg/Riba treated HCV patients in comparison to treatment naïve HCV group. In HCV patients with antinuclear antibody (ANA) +ve, Tregs markers were significantly decreased in comparison to all other studied groups. Teffs markers were significantly elevated in all HCV groups in comparison to control and in HCV group with ANA +ve in comparison to treatment naïve HCV group. CONCLUSION Elevated Tregs cells in chronic HCV patients dampen both CD4+ and CD8+ autologous T cell immune response. Interferon-α and ribavirin therapy suppress proliferation of Tregs. More significant suppression of Tregs was observed in HCV patients with autoantibodies favoring pathological autoimmune response. PMID:27843539

Predictors of Immunosuppressive Regulatory T Lymphocytes in Healthy Women

PubMed Central

Hampras, Shalaka S.; Nesline, Mary; Wallace, Paul K.; Odunsi, Kunle; Furlani, Nicholas; Davis, Warren; Moysich, Kirsten B.

2012-01-01

Immunosuppressive regulatory T (Treg) cells play an important role in antitumor immunity, self-tolerance, transplantation tolerance, and attenuation of allergic response. Higher proportion of Treg cells has been observed in peripheral blood of cancer cases compared to controls. Little is known about potential epidemiological predictors of Treg cell levels in healthy individuals. We conducted a cross-sectional study including 75 healthy women, between 20 and 80 years of age, who participated in the Data Bank and BioRepository (DBBR) program at Roswell Park Cancer Institute (RPCI), Buffalo, NY, USA. Peripheral blood levels of CD4+CD25+FOXP3+ Treg cells were measured using flow cytometric analysis. A range of risk factors was evaluated using Wilcoxon Rank-Sum test, Kruskal-Wallis test, and linear regression. Age, smoking, medications for treatment of osteoporosis, postmenopausal status, body mass index (BMI), and hormone replacement therapy (HRT) were found to be significant positive predictors of Treg cell levels in peripheral blood (P ≤ 0.05). Higher education, exercise, age at first birth, oral contraceptives, and use of Ibuprofen were found be significant (P < 0.05) negative predictors of Treg levels. Thus, various epidemiological risk factors might explain interindividual variation in immune response to pathological conditions, including cancer. PMID:22969801

CD28-CD80 interactions control regulatory T cell motility and immunological synapse formation1,2

PubMed Central

Thauland, Timothy J.; Koguchi, Yoshinobu; Dustin, Michael L.; Parker, David C.

2014-01-01

Regulatory T cells (Tregs) are essential for tolerance to self and environmental antigens, acting in part by downmodulating costimulatory molecules on the surface of dendritic cells (DCs) and altering naïve CD4 T cell-DC interactions. Here, we show that Tregs form stable conjugates with DCs before, but not after, they decrease surface expression of the costimulatory molecule CD80 on the DCs. We use supported planar bilayers to show that Tregs dramatically slow down, but maintain a highly polarized and motile phenotype after recognizing antigen in the absence of costimulation. These motile cells are characterized by distinct accumulations of LFA-1-ICAM-1 in the lamella and TCR-MHC in the uropod, consistent with a motile immunological synapse or ‘kinapse’. However, in the presence of high, but not low, concentrations of CD80, Tregs form stationary, symmetrical synapses. Using blocking antibodies, we show that, while CTLA-4 is required for CD80 downmodulation, CD28-CD80 interactions are critical for modulating Treg motility in the presence of antigen. Together, these results support the hypothesis that Tregs are tuned to alter their motility depending on costimulatory signals. PMID:25355918

TSC1 regulates the balance between effector and regulatory T cells.

PubMed

Park, Yoon; Jin, Hyung-Seung; Lopez, Justine; Elly, Chris; Kim, Gisen; Murai, Masako; Kronenberg, Mitchell; Liu, Yun-Cai

2013-12-01

Mammalian target of rapamycin (mTOR) plays a crucial role in the control of T cell fate determination; however, the precise regulatory mechanism of the mTOR pathway is not fully understood. We found that T cell-specific deletion of the gene encoding tuberous sclerosis 1 (TSC1), an upstream negative regulator of mTOR, resulted in augmented Th1 and Th17 differentiation and led to severe intestinal inflammation in a colitis model. Conditional Tsc1 deletion in Tregs impaired their suppressive activity and expression of the Treg marker Foxp3 and resulted in increased IL-17 production under inflammatory conditions. A fate-mapping study revealed that Tsc1-null Tregs that lost Foxp3 expression gained a stronger effector-like phenotype compared with Tsc1-/- Foxp3+ Tregs. Elevated IL-17 production in Tsc1-/- Treg cells was reversed by in vivo knockdown of the mTOR target S6K1. Moreover, IL-17 production was enhanced by Treg-specific double deletion of Tsc1 and Foxo3a. Collectively, these studies suggest that TSC1 acts as an important checkpoint for maintaining immune homeostasis by regulating cell fate determination.

Zinc Induces Dendritic Cell Tolerogenic Phenotype and Skews Regulatory T cell – Th17 Balance

PubMed Central

George, Mariam Mathew; Vignesh, Kavitha Subramanian; Landero Figueroa, Julio A.; Caruso, Joseph A.; Deepe, George S.

2016-01-01

Zn is an essential metal for development and maintenance of both the innate and adaptive compartments of the immune system. Zn homeostasis impacts maturation of dendritic cells (DCs) that are important in shaping T cell responses. The mechanism by which Zn regulates the tolerogenic phenotype of DCs remains largely unknown. In this study, we investigated the effect of Zn on DC phenotype and the generation of forkhead box P3 (FoxP3+) regulatory T cells (Tregs) using a model of Histoplasma capsulatum fungal infection. Exposure of bone marrow derived DCs to Zn in vitro induced a tolerogenic phenotype by diminishing surface major histocompatibility complex (MHC)II and promoting the tolerogenic markers, programmed death-ligand (PD-L)1, PD-L2 and the tryptophan degrading enzyme, indoleamine 2,3 dioxygenase (IDO). Zn triggered tryptophan degradation by IDO and kynurenine production by DCs and strongly suppressed the proinflammatory response to stimulation by toll like receptor (TLR) ligands. In vivo, Zn supplementation and subsequent H. capsulatum infection supressed MHCII on DCs, enhanced PD-L1 and PD-L2 expression on MHCIIlo DCs and skewed the Treg - Th17 balance in favour of FoxP3+ Tregs while decreasing Th17 cells. Thus, Zn shapes the tolerogenic potential of DCs in vitro and in vivo and promotes Tregs during fungal infection. PMID:27465530

[Th17 and Treg cell levels in patients with sarcoidosis and their relation to disease activation].

PubMed

Weng, Yue-song; Wang, Hua-ying; Lv, Ding-feng; Fu, Zhong-ming; Yu, Wan-jun

2015-03-01

To investigate the Th17 cell and Treg cell levels in patients with sarcoidosis, and their relation to disease activation and glucocorticoids treatment. Twenty-three sarcoidosis patients admitted in Yinzhou People's Hospital from January 2009 to December 2013 and 25 healthy subjects (controls) were included in this study. The blood samples and bronchoalveolar lavage fluid (BALF) samples were collected in all patients before and after glucocorticoids treatment. The serum angiotensin converting enzyme (SACE) levels were detected. The percentages of Th17 cells and Treg cells in peripheral blood and BALF were determined by flow cytometry, the concentrations of cytokines in serum and supernatants of BALF were measured by enzyme-linked immunosorbent assay (ELISA). The levels of ROR-γt and Foxp3 mRNA transcripts in peripheral blood mononuclear cells (PBMC) were determined by real-time quantitative PCR. The potential correlation between the percentages of Th17 or Treg cells and SACE levels was evaluated. Compared with healthy controls, significantly higher frequencies of Th17 cells (4.34%±0.89% vs 1.60% ± 0.42%), lower frequencies of Treg cells (1.28% ± 0.37% vs 3.39% ± 0.50%) in peripheral blood were observed. Higher level of ROR-γt mRNA (21.31 ± 3.55 vs 3.63 ± 1.00) and lower level of Foxp3 mRNA (1.60 ± 0.24 vs 3.12 ± 0.76) in peripheral blood were detected in sarcoidosis patients in active stage (before glucocorticoids treatment) (all P<0.01). After the treatment of glucocorticoids, these index in peripheral blood were significantly improved (Th17 cells 2.16% ± 0.68%，Treg cells 2.21% ± 0.42%, ROR-γt mRNA 10.15 ± 1.93, Foxp3 mRNA 2.44 ± 0.38) ( all P<0.05). The changing trends of Th17 and Treg cell cytokines levels in serum were consistent with two type cells. Meanwhile, the changing trends of above index in BALF of patients treated by glucocorticoids were consistent with those in sarcoidosis patients in active stage. The increased ratios of Th17 cells to Treg cells were positively correlated with the level of serum SACE (r= 0.781). The imbalance of Th17 cells and Treg cells in peripheral blood and airway may be involved in the pathogenesis of sarcoidosis, which was associated with the activity of disease, and the treatment of glucocorticoids may achieve a therapeutic effect by correcting the immune imbalance.

Combating Hepatitis B and C through immunological approach

NASA Astrophysics Data System (ADS)

Nugraha Susilawati, Tri; Setyawan, Sigit; Pramana, T. Y.; Mudigdo, Ambar; Agung Prasetyo, Afiono

2018-05-01

Infections with hepatitis B and C viruses are the main factors contributing to the development of chronic liver disease and have been known as the major global health problems. This paper examines evidence that demonstrates the involvement of host immune responses in hepatitis B and C, particularly in the protection against immune-mediated liver injury. The proposed mechanisms of protection range from T cell responses that facilitate spontaneous resolution during acute infection and prevent persistent infection to immunoregulatory cytokines that inhibit destructive immune responses. Regulatory T cells (Tregs), TGF-β1, IL-4, and IL-10 are the main components of the immune system that play an important role in the protection mechanisms against the detrimental effects of hepatitis B and C viruses in liver tissues. Thus, factors contributing to increased Tregs activity and immunoregulatory cytokines should be elaborated. Recent studies reported factors that facilitate the development of Tregs during hepatitis C viral infection include HCV epitope, expression of miR 146a in monocytes and the Tim-3/Gal-9 pathway. On the other hand, the generation of Tregs is inhibited by IL-6 produced during inflammation. These findings suggest that immunomodulation strategy should be further developed and applied in the management of hepatitis B and C.

Decreased circulating T regulatory lymphocytes in obese patients undergoing bariatric surgery.

PubMed

Agabiti-Rosei, Claudia; Trapletti, Valentina; Piantoni, Silvia; Airò, Paolo; Tincani, Angela; De Ciuceis, Carolina; Rossini, Claudia; Mittempergher, Francesco; Titi, Amin; Portolani, Nazario; Caletti, Stefano; Coschignano, Maria Antonietta; Porteri, Enzo; Tiberio, Guido A M; Pileri, Paola; Solaini, Leonardo; Kumar, Rajesh; Ministrini, Silvia; Agabiti Rosei, Enrico; Rizzoni, Damiano

2018-01-01

It has been previously demonstrated that T lymphocytes may be involved in the development of hypertension and microvascular remodeling, and that circulating T effector lymphocytes may be increased in hypertension. In particular, Th1 and Th 17 lymphocytes may contribute to the progression of hypertension and microvascular damage while T-regulatory (Treg) lymphocytes seem to be protective in this regard. However, no data is available about patients with severe obesity, in which pronounced microvascular alterations were observed. We have investigated 32 severely obese patients undergoing bariatric surgery, as well as 24 normotensive lean subjects and 12 hypertensive lean subjects undergoing an elective surgical intervention. A peripheral blood sample was obtained before surgery for assessment of CD4+ T lymphocyte subpopulations. Lymphocyte phenotype was evaluated by flow cytometry in order to assess T-effector and Treg lymphocytes. A marked reduction of several Treg subpopulations was observed in obese patients compared with controls, together with an increased in CD4+ effector memory T-effector cells. In severely obese patients, Treg lymphocytes are clearly reduced and CD4+ effector memory cells are increased. It may be hypothesized that they might contribute to the development of marked microvascular alterations previously observed in these patients.

Targeting Peripheral-Derived Regulatory T Cells as a Means of Enhancing Immune Responses Directed against Prostate Cancer

DTIC Science & Technology

2017-08-01

Award Number: W81XWH-15-1-0328 TITLE: Targeting Peripheral-Derived Regulatory T Cells as a Means of Enhancing Immune Responses Directed against...1 August 2016 - 31 July 2017 4. TITLE AND SUBTITLE Targeting Peripheral-Derived Regulatory T Cells as a Means of Enhancing Immune Responses Directed...discovered that a subset of regulatory T cells (Tregs), termed peripheral-derived Tregs (pTregs), impair immune responses directed against tumor

Type I IFN gene delivery suppresses regulatory T cells within tumors.

PubMed

Hashimoto, H; Ueda, R; Narumi, K; Heike, Y; Yoshida, T; Aoki, K

2014-12-01

Type I interferon (IFN) is a pleiotropic cytokine regulating the cancer cell death and immune response. IFN-α can, as we have also reported, effectively induce an antitumor immunity by the activation of tumor-specific T cells and maturation of dendritic cells in various animal models. Unknown, however, is how the type I IFN alters the immunotolerant microenvironment in the tumors. Here, we found that intratumoral IFN-α gene transfer significantly decreased the frequency of regulatory T cells (Tregs) per CD4(+) T cells in tumors. The concentration of a Treg-inhibitory cytokine, interleukin (IL)-6, was correlated with the IFN-α expression level in tumors, and intratumoral CD11c(+) cells produced IL-6 in response to IFN-α stimulation. To confirm the role of IL-6 in the suppression of Tregs in tumors, an anti-IL-6 receptor antibody was administered in IFN-α-treated mice. The antibody increased the frequency of Tregs in the tumors, and attenuated systemic tumor-specific immunity induced by IFN-α. Furthermore, the IFN-α-mediated IL-6 production increased the frequency of Th17 cells in the tumors, which may be one of the mechanisms for the reduction of Tregs. The study demonstrated that IFN-α gene delivery creates an environment strongly supporting the enhancement of antitumor immunity through the suppression of Tregs.

TGF-β/Smad signaling pathway regulates Th17/Treg balance during Echinococcus multilocularis infection.

PubMed

Pang, Nannan; Zhang, Fengbo; Ma, Xiumin; Zhu, Yuejie; Zhao, Hui; Xin, Yan; Wang, Song; Chen, Zhaolun; Wen, Hao; Ding, Jianbing

2014-05-01

Alveolar echinococcosis (AE) is a severe parasitic disease caused by the infection of Echinococcus multilocularis (Em). Very little is known on the relationship between TGF-β/Smad signaling pathway and Treg/Th17 balance in the infected liver at different periods after Em infection. Using qRT-PCR, immunohistochemistry, flow cytometry and CBA assay, we measured the expression levels of TGF-β, Smad2/3/7, ROR-γt, Foxp3, IL-17, IL-10 and percentages of Th17 cells and Treg cells in mouse AE model, from day 2 to day 270 after infection. In the early stage of infection (day 2 to day 30), Smad7 was up-regulated and the TGF-β pathway was inactivated. In the middle stage of infection (day 30 to day 90), TGF-β and Smad2/3 were up-regulated. And levels of Treg cells, Foxp3, Th17 cells, RORγt, IL-17, IL-10 and IL-6 were significantly increased. In the late stage of infection (day 90 to day 270), Treg cells, Foxp3, TGF-β and IL-10 maintained at high levels whereas Th17 cells and IL-17 decreased significantly. TGF-β/Smad signaling pathway was activated during the chronic infection. Our data suggest that there were Treg/Th17 imbalance in the middle and especially in the late stage of Em infection and that Treg/Th17 imbalance may be regulated by TGF-β/Smad signaling pathway. Treg and Th17 subsets may be involved in regulating immune tolerance and tissue inflammation, and facilitating the long-term survival of Em in the host. Copyright © 2014 Elsevier B.V. All rights reserved.

Indoleamine 2,3-dioxygenase and regulatory T cells in acute myeloid leukemia.

PubMed

Mansour, Iman; Zayed, Rania A; Said, Fadwa; Latif, Lamyaa Abdel

2016-09-01

The microenvironment of acute myeloid leukemia (AML) is suppressive for immune cells. Regulatory T cells (Tregs) have been recognized to play a role in helping leukemic cells to evade immunesurveillance. The mesenchymal stem cells (MSCs) are essential contributors in immunomodulation of the microenvironment as they can promote differentiation of Tregs via the indoleamine 2,3-dioxygenase (IDO) pathway. The aim of the present work was to evaluate the expression of IDO in bone marrow derived MSCs and to study its correlation to percentage of Tregs. Thirty-seven adult bone marrow samples were cultured in appropriate culture medium to isolate MSCs. Successful harvest of MSCs was determined by plastic adherence, morphology, and positive expression of CD271 and CD105; negative expression of CD34 and CD45 using flowcytometry. MSCs were examined for IDO expression by immunocytochemistry using anti-IDO monoclonal antibody. CD4+ CD25+ cells (Tregs) were measured in bone marrow samples by flowcytometry. MSCs were successfully isolated from 20 of the 37 bone marrow samples cultured. MSCs showed higher expression of IDO and Tregs percentage was higher in AML patients compared to control subjects (P = 0.002 and P < 0.001, respectively). A positive correlation was found between IDO expression and Tregs percentage (P value = 0.012, r = 0.5). In this study, we revealed an association between high IDO expression in MSCs and elevated levels of Tregs which could have an important role in the pathogenesis of AML, providing immunosuppressive microenvironment.

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

PubMed Central

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

A new look at immune privilege of the eye: dual role for the vision-related molecule retinoic acid.

PubMed

Zhou, Ru; Horai, Reiko; Mattapallil, Mary J; Caspi, Rachel R

2011-10-15

The eye is an immunologically privileged and profoundly immunosuppressive environment. Early studies reported inhibition of T cell proliferation, IFN-γ production, and generation of regulatory T cells (Tregs) by aqueous humor (AH) and identified TGF-β as a critical factor. However, T cell subsets including Foxp3(+) Treg and Th17 were unknown at that time, as was the role of retinoic acid (RA) in Treg induction. Consequently, the effect of the ocular microenvironment on T cell lineage commitment and function, and the role of RA in this process, had not been explored. We now use gene-manipulated mice and highly purified T cell populations to demonstrate that AH suppresses lineage commitment and acquisition of Th1 and Th17 effector function of naive T cells, manifested as reduction of lineage-specific transcription factors and cytokines. Instead, AH promoted its massive conversion to Foxp3(+) Tregs that expressed CD25, GITR, CTLA-4, and CD103 and were functionally suppressive. TGF-β and RA were both needed and synergized for Treg conversion by AH, with TGF-β-enhancing T cell expression of RA receptor α. Newly converted Foxp3(+) Tregs were unstable, but were stabilized upon continued exposure to AH or by the DNA demethylating agent 5-aza-2'-deoxycytidine. In contrast, T cells already committed to effector function were resistant to the suppressive and Treg-inducing effects of AH. We conclude that RA in the eye plays a dual role: in vision and in immune privilege. Nevertheless, primed effector T cells are relatively insensitive to AH, helping to explain their ability to induce uveitis despite an inhibitory ocular microenvironment.

Rapamycin Monotherapy in Patients With Type 1 Diabetes Modifies CD4+CD25+FOXP3+ Regulatory T-Cells

PubMed Central

Monti, Paolo; Scirpoli, Miriam; Maffi, Paola; Piemonti, Lorenzo; Secchi, Antonio; Bonifacio, Ezio; Roncarolo, Maria-Grazia; Battaglia, Manuela

2008-01-01

OBJECTIVE—Rapamycin is an immunosuppressive drug currently used to prevent graft rejection in humans, which is considered permissive for tolerance induction. Rapamycin allows expansion of both murine and human naturally occurring CD4+CD25+FOXP3+ T regulatory cells (nTregs), which are pivotal for the induction and maintenance of peripheral tolerance. Preclinical murine models have shown that rapamycin enhances nTreg proliferation and regulatory function also in vivo. Objective of this study was to assess whether rapamycin has in vivo effects on human nTregs. RESEARCH DESIGN AND METHODS—nTreg numbers and function were examined in a unique set of patients with type 1 diabetes who underwent rapamycin monotherapy before islet transplantation. RESULTS—We found that rapamycin monotherapy did not alter the frequency and functional features, namely proliferation and cytokine production, of circulating nTregs. However, nTregs isolated from type 1 diabetic patients under rapamycin treatment had an increased capability to suppress proliferation of CD4+CD25− effector T-cells compared with that before treatment. CONCLUSIONS—These findings demonstrate that rapamycin directly affects human nTreg function in vivo, which consists of refitting their suppressive activity, whereas it does not directly change effector T-cell function. PMID:18559659

Increased CD4+CD45RA-FoxP3low cells alter the balance between Treg and Th17 cells in colitis mice.

PubMed

Ma, Ya-Hui; Zhang, Jie; Chen, Xue; Xie, You-Fu; Pang, Yan-Hua; Liu, Xin-Juan

2016-11-14

To investigate the role of regulatory T cell (Treg) subsets in the balance between Treg and T helper 17 (Th17) cells in various tissues from mice with dextran sulfate sodium-induced colitis. Treg cells, Treg cell subsets, Th17 cells, and CD4 + CD25 + FoxP3 + IL-17 + cells from the lamina propria of colon (LPC) and other ulcerative colitis (UC) mouse tissues were evaluated by flow cytometry. Forkhead box protein 3 (FoxP3), interleukin 17A (IL-17A), and RORC mRNA levels were assessed by real-time PCR, while interleukin-10 (IL-10) and IL-17A levels were detected with a Cytometric Beads Array. In peripheral blood monocytes (PBMC), mesenteric lymph node (MLN), lamina propria of jejunum (LPJ) and LPC from UC mice, Treg cell numbers were increased ( P < 0.05), and FoxP3 and IL-10 mRNA levels were decreased. Th17 cell numbers were also increased in PBMC and LPC, as were IL-17A levels in PBMC, LPJ, and serum. The number of FrI subset cells (CD4 + CD45RA + FoxP3 low ) was increased in the spleen, MLN, LPJ, and LPC. FrII subset cells (CD4 + CD45RA - FoxP3 high ) were decreased among PBMC, MLN, LPJ, and LPC, but the number of FrIII cells (CD4 + CD45RA - FoxP3 low ) and CD4 + CD25 + FoxP3 + IL-17A + cells was increased. FoxP3 mRNA levels in CD4 + CD45RA - FoxP3 low cells decreased in PBMC, MLN, LPJ, and LPC in UC mice, while IL-17A and RORC mRNA increased. In UC mice the distribution of Treg, Th17 cells, CD4 + CD45RA - FoxP3 high , and CD4 + CD45RA - FoxP3 low cells was higher in LPC relative to other tissues. Increased numbers of CD4 + CD45RA - FoxP3 low cells may cause an imbalance between Treg and Th17 cells that is mainly localized to the LPC rather than secondary lymphoid tissues.

Increased CD4+CD45RA-FoxP3low cells alter the balance between Treg and Th17 cells in colitis mice

PubMed Central

Ma, Ya-Hui; Zhang, Jie; Chen, Xue; Xie, You-Fu; Pang, Yan-Hua; Liu, Xin-Juan

2016-01-01

AIM To investigate the role of regulatory T cell (Treg) subsets in the balance between Treg and T helper 17 (Th17) cells in various tissues from mice with dextran sulfate sodium-induced colitis. METHODS Treg cells, Treg cell subsets, Th17 cells, and CD4+CD25+FoxP3+IL-17+ cells from the lamina propria of colon (LPC) and other ulcerative colitis (UC) mouse tissues were evaluated by flow cytometry. Forkhead box protein 3 (FoxP3), interleukin 17A (IL-17A), and RORC mRNA levels were assessed by real-time PCR, while interleukin-10 (IL-10) and IL-17A levels were detected with a Cytometric Beads Array. RESULTS In peripheral blood monocytes (PBMC), mesenteric lymph node (MLN), lamina propria of jejunum (LPJ) and LPC from UC mice, Treg cell numbers were increased (P < 0.05), and FoxP3 and IL-10 mRNA levels were decreased. Th17 cell numbers were also increased in PBMC and LPC, as were IL-17A levels in PBMC, LPJ, and serum. The number of FrI subset cells (CD4+CD45RA+FoxP3low) was increased in the spleen, MLN, LPJ, and LPC. FrII subset cells (CD4+CD45RA-FoxP3high) were decreased among PBMC, MLN, LPJ, and LPC, but the number of FrIII cells (CD4+CD45RA-FoxP3low) and CD4+CD25+FoxP3+IL-17A+ cells was increased. FoxP3 mRNA levels in CD4+CD45RA-FoxP3low cells decreased in PBMC, MLN, LPJ, and LPC in UC mice, while IL-17A and RORC mRNA increased. In UC mice the distribution of Treg, Th17 cells, CD4+CD45RA-FoxP3high, and CD4+CD45RA-FoxP3low cells was higher in LPC relative to other tissues. CONCLUSION Increased numbers of CD4+CD45RA-FoxP3low cells may cause an imbalance between Treg and Th17 cells that is mainly localized to the LPC rather than secondary lymphoid tissues. PMID:27895423

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

PubMed Central

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

Ex-vivo characterization of regulatory T cells in pulmonary tuberculosis patients, latently infected persons, and healthy endemic controls.

PubMed

Zewdie, Martha; Howe, Rawleigh; Hoff, Søren T; Doherty, T Mark; Getachew, Nahom; Tarekegne, Azeb; Tessema, Bamlak; Yamuah, Lawrence; Aseffa, Abraham; Abebe, Markos

2016-09-01

Regulatory T cells (Treg) are an essential arm of adaptive immunity not only in tolerance and autoimmunity but also in infectious diseases. In Tuberculosis (TB), it has been suggested that the frequency of Tregs is higher in the blood of TB patients when compared to healthy controls with subsequent decline after treatment. However, with the discovery that FOXP3, the hallmark marker of Tregs, is not exclusive to Tregs and the lack of specific markers for Tregs, it has been a challenge to fully understand the role of Tregs in TB. We isolated PBMC from smear positive TB patients (TB, N = 13) before and after treatment, latent TB infected participants (LTBI, N = 8), and healthy endemic controls (EC, N = 9) and evaluated the frequency of different populations of Tregs and expression of FOXP3 by flowcytometry using six markers. The findings in this study showed that the association of Treg frequency with TB disease depends on the phenotypic markers used. While the frequency of CD4(+)CD25(+/hi) T cells was higher in TB patients compared to LTBI individuals, there was no difference in the frequency of CD4(+)CD25(+)FOXP3(+)CD127(lo) Treg among TB, LTBI, or EC. However, delineation of Tregs into active and naïve subsets revealed a significant increase in FOXP3 expression in active primed Tregs (CD4(+)CD25(+)FOXP3(+)CD127(lo)CD45RO(+)Ki-67(+)) of TB patients compared to LTBI and EC; and a significantly higher frequency of resting primed (CD45RO(+)Ki-67(-)) Treg in QuantiFERON negative EC compared to TB patients. After treatment completion, there was a significant decline in the frequency of active primed Treg, median (IQR) from 12.4% (9.5-21.9) of Tregs to 9.3% (7.0-12.2); P = 0.003 Wilcoxon signed rank test. We conclude that Treg subsets may be differentially regulated and expressed in TB disease, cure, and infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ex-vivo characterization of regulatory T cells in pulmonary tuberculosis patients, latently infected persons, and healthy endemic controls

PubMed Central

Zewdie, Martha; Howe, Rawleigh; Hoff, Søren T.; Doherty, T. Mark; Getachew, Nahom; Tarekegne, Azeb; Tessema, Bamlak; Yamuah, Lawrence; Aseffa, Abraham; Abebe, Markos

2016-01-01

SUMMARY Background Regulatory T cells (Treg) are an essential arm of adaptive immunity not only in tolerance and autoimmunity but also in infectious diseases. In Tuberculosis (TB), it has been suggested that the frequency of Tregs is higher in the blood of TB patients when compared to healthy controls with subsequent decline after treatment. However, with the discovery that FOXP3, the hallmark marker of Tregs, is not exclusive to Tregs and the lack of specific markers for Tregs, it has been a challenge to fully understand the role of Tregs in TB. Method We isolated PBMC from smear positive TB patients (TB, N = 13) before and after treatment, latent TB infected participants (LTBI, N = 8), and healthy endemic controls (EC, N = 9) and evaluated the frequency of different populations of Tregs and expression of FOXP3 by flowcytometry using six markers. Results The findings in this study showed that the association of Treg frequency with TB disease depends on the phenotypic markers used. While the frequency of CD4+CD25+/hi T cells was higher in TB patients compared to LTBI individuals, there was no difference in the frequency of CD4+CD25+FOXP3+CD127lo Treg among TB, LTBI, or EC. However, delineation of Tregs into active and naïve subsets revealed a significant increase in FOXP3 expression in active primed Tregs (CD4+CD25+FOXP3+CD127loCD45RO+Ki-67+) of TB patients compared to LTBI and EC; and a significantly higher frequency of resting primed (CD45RO+Ki-67−) Treg in QuantiFERON negative EC compared to TB patients. After treatment completion, there was a significant decline in the frequency of active primed Treg, median (IQR) from 12.4% (9.5–21.9) of Tregs to 9.3% (7.0–12.2); P = 0.003 Wilcoxon signed rank test. We conclude that Treg subsets may be differentially regulated and expressed in TB disease, cure, and infection. PMID:27553411

Regulatory T cells (CD4(+)CD25(bright)FoxP3(+)) expansion in systemic sclerosis correlates with disease activity and severity.

PubMed

Slobodin, Gleb; Ahmad, Mohammad Sheikh; Rosner, Itzhak; Peri, Regina; Rozenbaum, Michael; Kessel, Aharon; Toubi, Elias; Odeh, Majed

2010-01-01

The role and function of T regulatory (Treg) cells have not been fully investigated in patients with systemic sclerosis (SSc). Ten patients with SSc donated 20ml of peripheral blood. Activity (Valentini) and severity (Medsger) scores for SSc were calculated for all patients. Healthy volunteers (controls) were matched to each patient by gender and age. CD4(+) cells were separated using the MACS system. The numbers of Treg cells were estimated by flow cytometry after staining for CD4, CD25, and FoxP3 and calculated as patient-to-control ratio separately for each experiment. Correlations with activity and severity indices of the disease were performed. Twenty-four-hour production of TGF-beta and IL-10 by activated CD4(+) cells was measured by ELISA in culture supernatants. The numbers of Treg cells, expressed as patient-to-control ratio, correlated significantly with both activity and severity indices (r=0.71, p=0.034 and r=0.67, p=0.044, respectively). ELISA-measured production of TGF-beta and IL-10 by CD4(+) cells was similar in patients and controls. Increased numbers of Treg cells are present in patients with SSc, correlating with activity and severity of the disease. This expansion of Treg cells was not accompanied, however, by heightened TGF-beta or IL-10 production. Further studies to elaborate the causes and functional significance of Treg cell expansion in SSc are needed. 2010 Elsevier Inc. All rights reserved.

High levels of FOXP3⁺ regulatory T cells in gastric MALT lymphoma predict responsiveness to Helicobacter pylori eradication.

PubMed

Iwaya, Yugo; Kobayashi, Motohiro; Momose, Masanobu; Hiraoka, Nobuyoshi; Sakai, Yasuhiro; Akamatsu, Taiji; Tanaka, Eiji; Ohtani, Haruo; Fukuda, Minoru; Nakayama, Jun

2013-10-01

Although Helicobacter pylori eradication is a first-line treatment of gastric MALT lymphoma, roughly 25% of patients do not respond to treatment. CD4⁺ FOXP3⁺ regulatory T (Treg) cells regulate immune responses in physiological conditions and various inflammatory conditions, including H. pylori-associated diseases. Our goal was to determine how Treg cells affect responsiveness to H. pylori eradication therapy. We performed dual immunohistochemistry for CD4 and FOXP3 to evaluate the prevalence of FOXP3⁺ Treg cells in the stomach of 63 patients with MALT lymphoma and 55 patients with chronic active gastritis. Receiver operating characteristic analysis was carried out to determine the best cut-off point in differentiating H. pylori eradication responders from nonresponders. Both the FOXP3⁺/CD4⁺ cell ratio and the absolute number of FOXP3⁺ cells per high-power field in MALT lymphoma were significantly greater in H. pylori eradication responders compared with nonresponders, suggesting that Treg cells function in regression mechanisms of MALT lymphomas. Cut-off points with good sensitivities and specificities were obtained to predict eradication outcome. A high number of Treg cells or a high ratio of Treg cells to the total number of CD4⁺ T cells in gastric MALT lymphoma could predict responsiveness to eradication therapy. © 2013 John Wiley & Sons Ltd.

Regulatory T cells facilitate the nuclear accumulation of inducible cAMP early repressor (ICER) and suppress nuclear factor of activated T cell c1 (NFATc1)

PubMed Central

Vaeth, Martin; Gogishvili, Tea; Bopp, Tobias; Klein, Matthias; Berberich-Siebelt, Friederike; Gattenloehner, Stefan; Avots, Andris; Sparwasser, Tim; Grebe, Nadine; Schmitt, Edgar; Hünig, Thomas; Serfling, Edgar; Bodor, Josef

2011-01-01

Inducible cAMP early repressor (ICER) is a transcriptional repressor, which, because of alternate promoter use, is generated from the 3′ region of the cAMP response modulator (Crem) gene. Its expression and nuclear occurrence are elevated by high cAMP levels in naturally occurring regulatory T cells (nTregs). Using two mouse models, we demonstrate that nTregs control the cellular localization of ICER/CREM, and thereby inhibit IL-2 synthesis in conventional CD4+ T cells. Ablation of nTregs in depletion of regulatory T-cell (DEREG) mice resulted in cytosolic localization of ICER/CREM and increased IL-2 synthesis upon stimulation. Direct contacts between nTregs and conventional CD4+ T cells led to nuclear accumulation of ICER/CREM and suppression of IL-2 synthesis on administration of CD28 superagonistic (CD28SA) Ab. In a similar way, nTregs communicated with B cells and induced the cAMP-driven nuclear localization of ICER/CREM. High levels of ICER suppressed the induction of nuclear factor of activated T cell c1 (Nfatc1) gene in T cells whose inducible Nfatc1 P1 promoter bears two highly conserved cAMP-responsive elements to which ICER/CREM can bind. These findings suggest that nTregs suppress T-cell responses by the cAMP-dependent nuclear accumulation of ICER/CREM and inhibition of NFATc1 and IL-2 induction. PMID:21262800

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

PubMed Central

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

Aberrant muscle antigen exposure in mice is sufficient to cause myositis in a Treg cell-deficient milieu.

PubMed

Young, Nicholas A; Sharma, Rahul; Friedman, Alexandra K; Kaffenberger, Benjamin H; Bolon, Brad; Jarjour, Wael N

2013-12-01

Myositis is associated with muscle-targeted inflammation and is observed in some Treg cell-deficient mouse models. Because an autoimmune pathogenesis has been strongly implicated, the aim of this study was to investigate the hypothesis that abnormal exposure to muscle antigens, as observed in muscle injury, can induce autoimmune-mediated myositis in susceptible hosts. FoxP3 mutant (scurfy) mice were mated to synaptotagmin VII (Syt VII) mutant mice, which resulted in a new mouse strain that combines impaired membrane resealing with Treg cell deficiency. Lymphocyte preparations from double-mutant mice were adoptively transferred intraperitoneally, with or without purified Treg cells, into recombination-activating gene 1 (RAG-1)-null recipients. Lymph node cells from mice with the FoxP3 mutation were transferred into RAG-1-null mice either 1) intraperitoneally in conjunction with muscle homogenate or purified myosin protein or 2) intramuscularly with or without cotransfer of purified Treg cells. FoxP3-deficient mouse lymph node cells transferred in conjunction with myosin protein or muscle homogenate induced robust skeletal muscle inflammation. The infiltrates consisted predominantly of CD4+ and CD8+ T cells, a limited number of macrophages, and no B cells. Significant inflammation was also seen in similar experiments using lymph node cells from FoxP3/Syt VII double-mutant mice but was absent in experiments using adoptive transfer of FoxP3 mutant mouse cells alone. The cotransfer of Treg cells completely suppressed myositis. These data, derived from a new, reproducible model, demonstrate the critical roles of Treg cell deficiency and aberrant muscle antigen exposure in the priming of autoreactive cells to induce myositis. This mouse system has multifaceted potential for examining the interplay in vivo between tissue injury and autoimmunity. © 2013 The Authors. Arthritis & Rheumatism is published by Wiley Periodicals, Inc. on behalf of the American College of Rheumatology.

Equine CD4+ CD25high T cells exhibit regulatory activity by close contact and cytokine-dependent mechanisms in vitro

PubMed Central

Hamza, Eman; Gerber, Vinzenz; Steinbach, Falko; Marti, Eliane

2011-01-01

Horses are particularly prone to allergic and autoimmune diseases, but little information about equine regulatory T cells (Treg) is currently available. The aim of this study therefore was to investigate the existence of CD4+ Treg cells in horses, determine their suppressive function as well as their mechanism of action. Freshly isolated peripheral blood mononuclear cells (PBMC) from healthy horses were examined for CD4, CD25 and forkhead box P3 (FoxP3) expression. We show that equine FoxP3 is expressed constitutively by a population of CD4+ CD25+ T cells, mainly in the CD4+ CD25high subpopulation. Proliferation of CD4+ CD25− sorted cells stimulated with irradiated allogenic PBMC was significantly suppressed in co-culture with CD4+ CD25high sorted cells in a dose-dependent manner. The mechanism of suppression by the CD4+ CD25high cell population is mediated by close contact as well as interleukin (IL)-10 and transforming growth factor-β1 (TGF-β1) and probably other factors. In addition, we studied the in vitro induction of CD4+ Treg and their characteristics compared to those of freshly isolated CD4+ Treg cells. Upon stimulation with a combination of concanavalin A, TGF-β1 and IL-2, CD4+ CD25+ T cells which express FoxP3 and have suppressive capability were induced from CD4+ CD25− cells. The induced CD4+ CD25high express higher levels of IL-10 and TGF-β1 mRNA compared to the freshly isolated ones. Thus, in horses as in man, the circulating CD4+ CD25high subpopulation contains natural Treg cells and functional Treg can be induced in vitro upon appropriate stimulation. Our study provides the first evidence of the regulatory function of CD4+ CD25+ cells in horses and offers insights into ex vivo manipulation of Treg cells. PMID:21977999

Differential Effects of Peptidoglycan Recognition Proteins on Experimental Atopic and Contact Dermatitis Mediated by Treg and Th17 Cells

PubMed Central

Park, Shin Yong; Gupta, Dipika; Kim, Chang H.; Dziarski, Roman

2011-01-01

Skin protects the body from the environment and is an important component of the innate and adaptive immune systems. Atopic dermatitis and contact dermatitis are among the most frequent inflammatory skin diseases and are both determined by multigenic predisposition, environmental factors, and aberrant immune response. Peptidoglycan Recognition Proteins (Pglyrps) are expressed in the skin and we report here that they modulate sensitivity to experimentally-induced atopic dermatitis and contact dermatitis. Pglyrp3 −/− and Pglyrp4 −/− mice (but not Pglyrp2 −/− mice) develop more severe oxazolone-induced atopic dermatitis than wild type (WT) mice. The common mechanism underlying this increased sensitivity of Pglyrp3 −/− and Pglyrp4 −/− mice to atopic dermatitis is reduced recruitment of Treg cells to the skin and enhanced production and activation Th17 cells in Pglyrp3 −/− and Pglyrp4 −/− mice, which results in more severe inflammation and keratinocyte proliferation. This mechanism is supported by decreased inflammation in Pglyrp3 −/− mice following in vivo induction of Treg cells by vitamin D or after neutralization of IL-17. By contrast, Pglyrp1 −/− mice develop less severe oxazolone-induced atopic dermatitis and also oxazolone-induced contact dermatitis than WT mice. Thus, Pglyrp3 and Pglyrp4 limit over-activation of Th17 cells by promoting accumulation of Treg cells at the site of chronic inflammation, which protects the skin from exaggerated inflammatory response to cell activators and allergens, whereas Pglyrp1 has an opposite pro-inflammatory effect in the skin. PMID:21949809

TGF-β converts apoptotic stimuli into the signal for Th9 differentiation

PubMed Central

Takami, Mariko; Love, Robert B.; Iwashima, Makio

2012-01-01

Naturally arising CD4+CD25+FoxP3+ regulatory T cells (nTregs) play an essential role in maintenance of immune homeostasis and peripheral tolerance. Previously, we reported that conventional CD4+ and CD8+ T cells undergo p53-induced CD28-dependent apoptosis (PICA) when stimulated with a combination of immobilized anti-CD3 and anti-CD28 antibodies while nTregs expand robustly under the same conditions, suggesting that there is a differential survival mechanism against PICA between conventional T cells and nTregs. Here, we demonstrate that TGF-β signaling is required for nTregs to survive PICA. Conversely, when an active form of exogenous TGF-β is present, conventional T cells become resistant to PICA and undergo robust expansion instead of apoptosis, with reduction of the pro-apoptotic protein Bim and FoxO3a. A substantial fraction of PICA-resisted T cells expressed IL-9 (TH9 cells). Moreover, the presence of IL-6 along with TGF-β led to generation of TH17 cells from conventional T cells. Together, the data demonstrate a novel role for TGF-β in the homeostasis of Tregs and effector T cell differentiation/ expansion. PMID:22461692

Regulatory T-Cell Distribution within Lung Compartments in COPD.

PubMed

Sales, Davi S; Ito, Juliana T; Zanchetta, Ivy A; Annoni, Raquel; Aun, Marcelo V; Ferraz, Luiz Fernando S; Cervilha, Daniela A B; Negri, Elnara; Mauad, Thais; Martins, Mílton A; Lopes, Fernanda D T Q S

2017-10-01

The importance of the adaptive immune response, specifically the role of regulatory T (Treg) cells in controlling the obstruction progression in smokers, has been highlighted. To quantify the adaptive immune cells in different lung compartments, we used lung tissues from 21 never-smokers without lung disease, 22 current and/or ex-smokers without lung disease (NOS) and 13 current and/or ex-smokers with chronic obstructive pulmonary disease (COPD) for histological analysis. We observed increased T, B, IL-17 and BAFF + cells in small and large airways of COPD individuals; however, in the NOS, we only observed increase in T and IL-17 + cells only in small airways. A decrease in the density of Treg + , TGF-β + and IL-10 + in small and large airways was observed only in COPD individuals. In the lymphoid tissues, Treg, T,B-cells and BAFF + cells were also increased in COPD; however, changes in Treg inhibitory associated cytokines were not observed in this compartment. Therefore, our results suggest that difference in Treg + cell distributions in lung compartments and the decrease in TGF-β + and IL-10 + cells in the airways may lead to the obstruction in smokers.

Smad4 in T cells plays a protective role in the development of autoimmune Sjögren's syndrome in the nonobese diabetic mouse.

PubMed

Kim, Donghee; Kim, Jae Young; Jun, Hee-Sook

2016-12-06

We investigated the role of Smad4, a signaling molecule of the TGF-beta pathway, in T cells on the pathology of Sjögren's syndrome (SS) in nonobese diabetic (NOD) mice, an animal model of SS. T cell-specific Smad4-deleted (Smad4fl/fl,CD4-Cre; Smad4 tKO) NOD mice had accelerated development of SS compared with wild-type (Smad4+/+,CD4-Cre; WT) NOD mice, including increased lymphocyte infiltration into exocrine glands, decreased tear and saliva production, and increased levels of autoantibodies at 12 weeks of age. Activated/memory T cells and cytokine (IFN-γ, IL-17)-producing T cells were increased in Smad4 tKO NOD mice, however the proportion and function of regulatory T (Treg) cells were not different between Smad4 tKO and WT NOD mice. Effector T (Teff) cells from Smad4 tKO NOD mice were less sensitive than WT Teff cells to suppression by Treg cells. Th17 differentiation capability of Teff cells was similar between Smad4 tKO and WT NOD mice, but IL-17 expression was increased under inducible Treg skewing conditions in T cells from Smad4 tKO NOD mice. Our results demonstrate that disruption of the Smad4 pathway in T cells of NOD mice increases Teff cell activation resulting in upregulation of Th17 cells, indicating that Smad4 in T cells has a protective role in the development of SS in NOD mice.

Smad4 in T cells plays a protective role in the development of autoimmune Sjögren's syndrome in the nonobese diabetic mouse

PubMed Central

Kim, Donghee; Kim, Jae Young; Jun, Hee-Sook

2016-01-01

We investigated the role of Smad4, a signaling molecule of the TGF-beta pathway, in T cells on the pathology of Sjögren's syndrome (SS) in nonobese diabetic (NOD) mice, an animal model of SS. T cell-specific Smad4-deleted (Smad4fl/fl,CD4-Cre; Smad4 tKO) NOD mice had accelerated development of SS compared with wild-type (Smad4+/+,CD4-Cre; WT) NOD mice, including increased lymphocyte infiltration into exocrine glands, decreased tear and saliva production, and increased levels of autoantibodies at 12 weeks of age. Activated/memory T cells and cytokine (IFN-γ, IL-17)-producing T cells were increased in Smad4 tKO NOD mice, however the proportion and function of regulatory T (Treg) cells were not different between Smad4 tKO and WT NOD mice. Effector T (Teff) cells from Smad4 tKO NOD mice were less sensitive than WT Teff cells to suppression by Treg cells. Th17 differentiation capability of Teff cells was similar between Smad4 tKO and WT NOD mice, but IL-17 expression was increased under inducible Treg skewing conditions in T cells from Smad4 tKO NOD mice. Our results demonstrate that disruption of the Smad4 pathway in T cells of NOD mice increases Teff cell activation resulting in upregulation of Th17 cells, indicating that Smad4 in T cells has a protective role in the development of SS in NOD mice. PMID:27880731

Increased Regulatory T-Cell Percentage Contributes to Poor CD4(+) Lymphocytes Recovery: A 2-Year Prospective Study After Introduction of Antiretroviral Therapy.

PubMed

Saison, Julien; Maucort Boulch, Delphine; Chidiac, Christian; Demaret, Julie; Malcus, Christophe; Cotte, Laurent; Poitevin-Later, Francoise; Miailhes, Patrick; Venet, Fabienne; Trabaud, Mary Anne; Monneret, Guillaume; Ferry, Tristan

2015-04-01

Background.  The primary aim of this study was to determine the impact of regulatory T cells (Tregs) percentage on immune recovery in human immunodeficiency virus (HIV)-infected patients after antiretroviral therapy introduction. Methods.  A 2-year prospective study was conducted in HIV-1 chronically infected naive patients with CD4 count <500 cells/mm(3). Regulatory T cells were identified as CD4(+)CD25(high)CD127(low) cells among CD4(+) lymphocytes. Effect of Treg percentage at inclusion on CD4 evolution overtime was analyzed using a mixed-effect Poisson regression for count data. Results.  Fifty-eight patients were included (median CD4 = 293/mm(3), median Treg percentage = 6.1%). Percentage of Treg at baseline and CD4 nadir were independently related to the evolution of CD4 absolute value according to time: (1) at any given nadir CD4 count, 1% increase of initial Treg was associated with a 1.9% lower CD4 absolute value at month 24; (2) at any given Treg percentage at baseline, 10 cell/mm(3) increase of CD4 nadir was associated with a 2.4% increase of CD4 at month 24; and (3) both effects did not attenuate with time. The effect of Treg at baseline on CD4 evolution was as low as the CD4 nadir was high. Conclusions.  Regulatory T-cell percentage at baseline is a strong independent prognostic factor of immune recovery, particularly among patients with low CD4 nadir.

In Situ Detection of Regulatory T Cells in Human Genital Herpes Simplex Virus Type 2 (HSV-2) Reactivation and Their Influence on Spontaneous HSV-2 Reactivation.

PubMed

Milman, Neta; Zhu, Jia; Johnston, Christine; Cheng, Anqi; Magaret, Amalia; Koelle, David M; Huang, Meei-Li; Jin, Lei; Klock, Alexis; Layton, Erik D; Corey, Lawrence

2016-07-01

Herpes simplex virus type 2 (HSV-2) reactivation is accompanied by a sustained influx of CD4(+) and CD8(+) T cells that persist in genital tissue for extended periods. While CD4(+) T cells have long been recognized as being present in herpetic ulcerations, their role in subclinical reactivation and persistence is less well known, especially the role of CD4(+) regulatory T cells (Tregs). We characterized the Treg (CD4(+)Foxp3(+)) population during human HSV-2 reactivation in situ in sequential genital skin biopsy specimens obtained from HSV-2-seropositive subjects at the time of lesion onset up to 8 weeks after healing. High numbers of Tregs infiltrated to the site of viral reactivation and persisted in proximity to conventional CD4(+) T cells (Tconvs) and CD8(+) T cells. Treg density peaked during the lesion stage of the reactivation. The number of Tregs from all time points (lesion, healed, 2 weeks after healing, 4 weeks after healing, and 8 weeks after healing) was significantly higher than in control biopsy specimens from unaffected skin. There was a direct correlation between HSV-2 titer and Treg density. The association of a high Treg to Tconv ratio with high viral shedding suggests that the balance between regulatory and effector T cells influences human HSV-2 disease. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Deletion of Fanca or Fancd2 dysregulates Treg in mice.

PubMed

Du, Wei; Erden, Ozlem; Wilson, Andrew; Sipple, Jared M; Schick, Jonathan; Mehta, Parinda; Myers, Kasiani C; Steinbrecher, Kris A; Davies, Stella M; Pang, Qishen

2014-03-20

Fanconi anemia (FA) is a genetic disorder associated with bone marrow (BM) failure and leukemia. Recent studies demonstrate variable immune defects in FA. However, the cause for FA immunodeficiency is unknown. Here we report that deletion of Fanca or Fancd2 dysregulates the suppressive activity of regulatory T cells (Tregs), shown functionally as exacerbation of graft-vs-host disease (GVHD) in mice. Recipient mice of Fanca(-/-) or Fancd2(-/-) BM chimeras exhibited severe acute GVHD after allogeneic BM transplantation (BMT). T cells from Fanca(-/-) or Fancd2(-/-) mice induced higher GVHD lethality than those from wild-type (WT) littermates. FA Tregs possessed lower proliferative suppression potential compared with WT Tregs, as demonstrated by in vitro proliferation assay and BMT. Analysis of CD25(+)Foxp3(+) Tregs indicated that loss of Fanca or Fancd2 dysregulated Foxp3 target gene expression. Additionally, CD25(+)Foxp3(+) Tregs of Fanca(-/-) or Fancd2(-/-) mice were less efficient in suppressing the production of GVHD-associated inflammatory cytokines. Consistently, aberrant NF-κB activity was observed in infiltrated T cells from FA GVHD mice. Conditional deletion of p65 in FA Tregs decreased GVHD mortality. Our study uncovers an essential role for FA proteins in maintaining Treg homeostasis, possibly explaining, at least in part, the immune deficiency reported in some FA patients.

GP96 is a GARP chaperone and controls regulatory T cell functions.

PubMed

Zhang, Yongliang; Wu, Bill X; Metelli, Alessandra; Thaxton, Jessica E; Hong, Feng; Rachidi, Saleh; Ansa-Addo, Ephraim; Sun, Shaoli; Vasu, Chenthamarakshan; Yang, Yi; Liu, Bei; Li, Zihai

2015-02-01

Molecular chaperones control a multitude of cellular functions via folding chaperone-specific client proteins. CD4+FOXP3+ Tregs play key roles in maintaining peripheral tolerance, which is subject to regulation by multiple molecular switches, including mTOR and hypoxia-inducible factor. It is not clear whether GP96 (also known as GRP94), which is a master TLR and integrin chaperone, controls Treg function. Using murine genetic models, we demonstrated that GP96 is required for Treg maintenance and function, as loss of GP96 resulted in instability of the Treg lineage and impairment of suppressive functions in vivo. In the absence of GP96, Tregs were unable to maintain FOXP3 expression levels, resulting in systemic accumulation of pathogenic IFN-γ-producing and IL-17-producing T cells. We determined that GP96 serves as an essential chaperone for the cell-surface protein glycoprotein A repetitions predominant (GARP), which is a docking receptor for latent membrane-associated TGF-β (mLTGF-β). The loss of both GARP and integrins on GP96-deficient Tregs prevented expression of mLTGF-β and resulted in inefficient production of active TGF-β. Our work demonstrates that GP96 regulates multiple facets of Treg biology, thereby placing Treg stability and immunosuppressive functions strategically under the control of a major stress chaperone.

Resting and Activated Natural Tregs Decrease in the Peripheral Blood of Patients with Atherosclerosis.

PubMed

Yazdani, Mohammadreza; Khosropanah, Shahdad; Hosseini, Ahmad; Doroudchi, Mehrnoosh

2016-12-01

Atherosclerosis is a chronic inflammatory disease affecting large and medium arteries. CD4+ T cells are known to play a role in the progression of the disease. CD4+CD25+Foxp3+ natural Treg (nTreg) cells seem to have a protective role in the disease and their reduction in acute coronary syndrome is recently shown. To investigate the frequency of nTreg subsets in the peripheral blood of patients with atherosclerosis. Confirmation of atherosclerosis was done by angiography and 15 ml heparinized blood was obtained from each of the 13 non-diabetic patients and 13 non-diabetic, non-smoker individuals with normal/insignificant coronary artery disease confirmed by angiography. Lipid profiles of the patients and controls were measured at the time of sampling. Mononuclear cells were used for both RNA extraction and immunophenotyping by real-time PCR and flowcytometry techniques, respectively. In natural Treg subsets, the frequency of CD4+CD45RO-CD25+Foxp3lo T-cells (resting nTregs) was greater in controls than patients (p=0.02). The frequency of CD4+CD45RO+CD25hiFoxp3hi T-cells (activated nTregs) was significantly higher in controls compared with patients (p=0.02). However, the frequency of CD4+CD25+CD45RO+Foxp3- T-cells (effector/memory T-cell) increased in patients compared with controls (p=0.01). Both the MFI and gene expression of Foxp3 were higher in control group than in patients (p=0.015 and p=0.017, respectively). Moreover, the TGF-β gene expression showed a decrease in the peripheral blood mononuclear cells of patients compared with controls (p=0.03). Decrease in both subsets of resting and activated nTregs along with a decrease in the expression of Foxp3 and TGF-β genes in patients with atherosclerosis suggests phenotypic changes in these subsets, which may as well be correlated with a more inflammatory profile in their lymphocytes.

Immunosuppression-Independent Role of Regulatory T Cells against Hypertension-Driven Renal Dysfunctions.

PubMed

Fabbiano, Salvatore; Menacho-Márquez, Mauricio; Robles-Valero, Javier; Pericacho, Miguel; Matesanz-Marín, Adela; García-Macías, Carmen; Sevilla, María A; Montero, M J; Alarcón, Balbino; López-Novoa, José M; Martín, Pilar; Bustelo, Xosé R

2015-10-01

Hypertension-associated cardiorenal diseases represent one of the heaviest burdens for current health systems. In addition to hemodynamic damage, recent results have revealed that hematopoietic cells contribute to the development of these diseases by generating proinflammatory and profibrotic environments in the heart and kidney. However, the cell subtypes involved remain poorly characterized. Here we report that CD39(+) regulatory T (TREG) cells utilize an immunosuppression-independent mechanism to counteract renal and possibly cardiac damage during angiotensin II (AngII)-dependent hypertension. This mechanism relies on the direct apoptosis of tissue-resident neutrophils by the ecto-ATP diphosphohydrolase activity of CD39. In agreement with this, experimental and genetic alterations in TREG/TH cell ratios have a direct impact on tissue-resident neutrophil numbers, cardiomyocyte hypertrophy, cardiorenal fibrosis, and, to a lesser extent, arterial pressure elevation during AngII-driven hypertension. These results indicate that TREG cells constitute a first protective barrier against hypertension-driven tissue fibrosis and, in addition, suggest new therapeutic avenues to prevent hypertension-linked cardiorenal diseases. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Autologous regulatory T cells can suppress the proliferation of lymphoma cell line in vitro].

PubMed

Ying, Zhi-Tao; Guo, Jun; Ren, Jun; Kong, Yan; Yuan, Zhi-Hong; Liu, Xi-Juan; Zhang, Chen; Zheng, Wen; Song, Yu-Qin; Zhang, Yun-Tao; Zhu, Jun

2009-06-01

This study was aimed to investigate the suppressive effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cell line and to explore its mechanism. C57BL/6 Mouse Treg cells were isolated by MACS (magnetic cell sorting). The purity and the expression of Foxp3 were detected by flow cytometry. The suppressive effect of sorted Treg cells on EL4 cells was detected by MTT assay. The secretion of TGF-beta1 and IL-10 was examined by enzyme-linked immunosorbent assay (ELISA). The results showed that CD4(+)CD25(+) T cells could be successfully isolated by MACS with the purity reaching 91.6% and the expression level of Foxp3 was 78.9%. The ratio of viable cells was more than 95%. Regulatory T cells could suppress the proliferation of EL4 cells effectively in the presence of antigen presenting cells (APCs). And the suppressive effect was most significant at 1:1 ratio. In addition, the suppression still existed without APCs. TGF-beta1 and IL-10 could not be detected by ELISA. It is concluded that the Treg cells can suppress T lymphoma cell in vitro. The suppressive effect of Treg cells works in dose-dependent manner, but not in cytokine-dependent manner. The mechanism of this suppression may take effect through cell-cell contact.

GARP: a surface molecule of regulatory T cells that is involved in the regulatory function and TGF-β releasing.

PubMed

Sun, Liping; Jin, Hao; Li, Hui

2016-07-05

There are many molecules that define regulatory T cells (Tregs) phenotypically and functionally. Glycoprotein A repetitions predominant (GARP) is a transmembrane protein containing leucine rich repeats. Recently, GARP is found to express highly on the surface of activated Tregs. The combination of GARP and other surface molecules isolates Tregs with higher purity. Besides, GARP is a cell surface molecule of Tregs that maintains their regulatory function and homeosatsis. GARP has also been proved to promote the activation and secretion of transforming growth factor β (TGF-β). Moreover, its potential value in cancer immunotherapy is also discussed in this work.

LIGHT: A Novel Immunotherapy for Primary and Metastatic Prostate Cancer

DTIC Science & Technology

2013-09-01

and TRAMP-C2 LIGHT expressing cells to examine the frequency of Tregs subsequent to LIGHT interaction . These results reflect on the ability of LIGHT...cells. These data suggest that LIGHT interaction directly affects the induction of Tregs from a naïve CD4+ T cell population but also that this is not... interaction directly affects the induction of Tregs from a naïve CD4+ T cell population.  mPSCA TriVax induces infiltration of NK and MDSCs, whereas

Lactobacillus acidophilus Improves Intestinal Inflammation in an Acute Colitis Mouse Model by Regulation of Th17 and Treg Cell Balance and Fibrosis Development.

PubMed

Park, Jin-Sil; Choi, Jeong Won; Jhun, JooYeon; Kwon, Ji Ye; Lee, Bo-In; Yang, Chul Woo; Park, Sung-Hwan; Cho, Mi-La

2018-03-01

Disruption of the balance among the microbiota, epithelial cells, and resident immune cells in the intestine is involved in the pathogenesis of inflammatory bowel disease (IBD). Probiotics exert protective effects against IBD, and probiotic commensal Lactobacillus species are common inhabitants of the natural microbiota, especially in the gut. To investigate the effects of Lactobacillus acidophilus on the development of IBD, L. acidophilus was administered orally in mice with dextran sodium sulfate (DSS)-induced colitis. DSS-induced damage and the therapeutic effect of L. acidophilus were investigated. Treatment with L. acidophilus attenuated the severity of DSS-induced colitis. Specifically, it suppressed proinflammatory cytokines such as interleukin (IL)-6, tumor necrosis factor-α, IL-1β, and IL-17 in the colon tissues, which are produced by T helper (Th) 17 cells. Moreover, in vitro L. acidophilus treatment directly induced T regulatory (Treg) cells and the production of IL-10, whereas the production of IL-17 was suppressed in splenocytes. In addition, we found that L. acidophilus treatment decreased the levels of α-smooth muscle actin, a marker of activated myofibroblasts, and type I collagen compared with control mice. These results suggest that L. acidophilus may be a novel treatment for IBD by modulating the balance between Th17 and Treg cells, as well as fibrosis development.

Systems Modeling of Molecular Mechanisms Controlling Cytokine-driven CD4+ T Cell Differentiation and Phenotype Plasticity

PubMed Central

Carbo, Adria; Hontecillas, Raquel; Kronsteiner, Barbara; Viladomiu, Monica; Pedragosa, Mireia; Lu, Pinyi; Philipson, Casandra W.; Hoops, Stefan; Marathe, Madhav; Eubank, Stephen; Bisset, Keith; Wendelsdorf, Katherine; Jarrah, Abdul; Mei, Yongguo; Bassaganya-Riera, Josep

2013-01-01

Differentiation of CD4+ T cells into effector or regulatory phenotypes is tightly controlled by the cytokine milieu, complex intracellular signaling networks and numerous transcriptional regulators. We combined experimental approaches and computational modeling to investigate the mechanisms controlling differentiation and plasticity of CD4+ T cells in the gut of mice. Our computational model encompasses the major intracellular pathways involved in CD4+ T cell differentiation into T helper 1 (Th1), Th2, Th17 and induced regulatory T cells (iTreg). Our modeling efforts predicted a critical role for peroxisome proliferator-activated receptor gamma (PPARγ) in modulating plasticity between Th17 and iTreg cells. PPARγ regulates differentiation, activation and cytokine production, thereby controlling the induction of effector and regulatory responses, and is a promising therapeutic target for dysregulated immune responses and inflammation. Our modeling efforts predict that following PPARγ activation, Th17 cells undergo phenotype switch and become iTreg cells. This prediction was validated by results of adoptive transfer studies showing an increase of colonic iTreg and a decrease of Th17 cells in the gut mucosa of mice with colitis following pharmacological activation of PPARγ. Deletion of PPARγ in CD4+ T cells impaired mucosal iTreg and enhanced colitogenic Th17 responses in mice with CD4+ T cell-induced colitis. Thus, for the first time we provide novel molecular evidence in vivo demonstrating that PPARγ in addition to regulating CD4+ T cell differentiation also plays a major role controlling Th17 and iTreg plasticity in the gut mucosa. PMID:23592971

Regulatory T cells and skeletal muscle regeneration.

PubMed

Schiaffino, Stefano; Pereira, Marcelo G; Ciciliot, Stefano; Rovere-Querini, Patrizia

2017-02-01

Skeletal muscle regeneration results from the activation and differentiation of myogenic stem cells, called satellite cells, located beneath the basal lamina of the muscle fibers. Inflammatory and immune cells have a crucial role in the regeneration process. Acute muscle injury causes an immediate transient wave of neutrophils followed by a more persistent infiltration of M1 (proinflammatory) and M2 (anti-inflammatory/proregenerative) macrophages. New studies show that injured muscle is also infiltrated by a specialized population of regulatory T (Treg) cells, which control both the inflammatory response, by promoting the M1-to-M2 switch, and the activation of satellite cells. Treg cells accumulate in injured muscle in response to specific cytokines, such as IL-33, and promote muscle growth by releasing growth factors, such as amphiregulin. Muscle repair during aging is impaired due to reduced number of Treg cells and can be enhanced by IL-33 supplementation. Migration of Treg cells could also contribute to explain the effect of heterochronic parabiosis, whereby muscle regeneration of aged mice can be improved by a parabiotically linked young partners. In mdx dystrophin-deficient mice, a model of human Duchenne muscular dystrophy, muscle injury, and inflammation is mitigated by expansion of the Treg-cell population but exacerbated by Treg-cell depletion. These findings support the notion that immunological mechanisms are not only essential in the response to pathogenic microbes and tumor cells but also have a wider homeostatic role in tissue repair, and open new perspectives for boosting muscle growth in chronic muscle disease and during aging. © 2016 Federation of European Biochemical Societies.

PGE2 contributes to TGF-β induced T regulatory cell function in human non-small cell lung cancer

PubMed Central

Baratelli, Felicita; Lee, Jay M; Hazra, Saswati; Lin, Ying; Walser, Tonya C; Schaue, Dorthe; Pak, Peter S; Elashoff, David; Reckamp, Karen; Zhang, Ling; Fishbein, Michael C; Sharma, Sherven; Dubinett, Steven M

2010-01-01

CD4+CD25bright regulatory T cells (Treg) play an important role in cancer-mediated immunosuppression. We and others have previously shown that prostaglandin E2 (PGE2) and transforming growth factor beta (TGF-β) induce CD4+CD25brightFOXP3+Treg. Based on these studies, we investigated the requirement for PGE2 in Treg induction by TGF-β. TGF-β stimulation of human CD4+ T cells induced COX-2-dependent production of PGE2. PGE2-neutralizing antibody treatment significantly reduced the suppressive function of TGF-β-induced Treg (TGF-β-Treg) in vitro. TGF-β concentration measured in the plasma of non-small cell lung cancer (NSCLC) patients directly correlated with the frequency of circulating CD4+CD25brightFOXP3+T cells. Flow cytometry analysis showed increased FOXP3 expression in circulating CD4+CD25+HLA-DR- cells of lung cancer patients compared to control subjects. Immunohistochemical analysis revealed co-expression of TGF-β, COX-2, and FOXP3 in serial sections from resected lung tumor tissues. All together these observations suggest interplay between TGF-β and COX-2 in the induction of Treg activities. Interrupting TGF-β and PGE2 signaling may be important in therapeutic interventions that aim to limit Tregfunction in lung cancer. PMID:20733946

Broncho-Vaxom attenuates allergic airway inflammation by restoring GSK3β-related T regulatory cell insufficiency.

PubMed

Fu, Ran; Li, Jian; Zhong, Hua; Yu, Dehong; Zeng, Xianping; Deng, Mengxia; Sun, Yueqi; Wen, Weiping; Li, Huabin

2014-01-01

Oral administration of bacterial extracts (eg, Broncho-Vaxom (BV)) has been proposed to attenuate asthma through modulating Treg cells. However, the underlying mechanism has not been fully characterized. This study sought to assess the effects of oral administration of BV on GSK-3β expression and Treg cells in ovalbumin (OVA)-induced asthmatic mice models. Asthmatic mice models were established with OVA challenge and treated with oral administration of BV. Next, infiltration of inflammatory cells including eosinophil and neutrophils, mucous metaplasia, levels of Th1/Th2/Treg-typed cytokines and expression of GSK3β and Foxp3 were examined in asthmatic mice models by histological analysis, Bio-Plex and western blot, respectively. Moreover, the frequencies of Treg cells were evaluated in cultured splenocytes by flow cytometry in the presence of BV or GSK3β siRNA interference. We found significant decrease of infiltrated inflammatory cells in bronchoalveolar lavage fluid (BALF) in asthmatic mice models after oral administration of BV. Oral administration of BV was shown to significantly suppress mucus metaplasia, Th2-typed cytokine levels and GSK3β expression while increasing Foxp3 production in asthmatic mice models. Moreover, BV significantly enhanced GSK3β-related expansion of Treg cells in cultured spleen cells in vitro. Our findings provide evidence that oral administration of BV is capable of attenuating airway inflammation in asthmatic mice models, which may be associated with GSK3β-related expansion of Treg cells.

Abdominal {gamma}-Radiation Induces an Accumulation of Function-Impaired Regulatory T Cells in the Small Intestine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Billiard, Fabienne; Buard, Valerie; Benderitter, Marc

Purpose: To assess the frequency and the functional characteristics of one major component of immune tolerance, the CD4{sup +}FoxP3{sup +} regulatory T cells (Tregs) in a mouse model of abdominal irradiation. Methods and Materials: Mice were exposed to a single abdominal dose of {gamma}-radiation (10 Gy). We evaluated small intestine Treg infiltration by Foxp3 immunostaining and the functional suppressive activity of Tregs isolated from mesenteric lymph nodes. Results: Foxp3 immunostaining showed that radiation induced a long-term infiltration of the intestine by Tregs (levels 5.5 times greater than in controls). Co-culture of Tregs from mesenteric lymph nodes with CD4{sup +} effectormore » cells showed that the Tregs had lost their suppressive function. This loss was associated with a significant decrease in the levels of Foxp3, TGF-{beta}, and CTLA-4 mRNA, all required for optimal Treg function. At Day 90 after irradiation, Tregs regained their suppressive activity as forkhead box P3 (Foxp3), transforming growth factor beta (TGF-{beta}), and cytotoxic T-lymphocyte antigen 4 (CTLA-4) expression returned to normal. Analysis of the secretory function of mesenteric lymph node Tregs, activated in vitro with anti-CD3/anti-CD28 Abs, showed that this dysfunction was independent of a defect in interleukin-10 secretion. Conclusion: Radiation caused a long-term accumulation of function-impaired Foxp3{sup +}CD4{sup +} Tregs in the intestine. Our study provides new insights into how radiation affects the immune tolerance in peripheral tissues.« less