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Lyu M, Wang S, Gao K, Wang L, Zhu X, Liu Y, Wang M, Liu X, Li B, Tian L. Dissecting the Landscape of Activated CMV-Stimulated CD4+ T Cells in Humans by Linking Single-Cell RNA-Seq With T-Cell Receptor Sequencing. Front Immunol 2021; 12:779961. [PMID: 34950144 PMCID: PMC8691692 DOI: 10.3389/fimmu.2021.779961] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/12/2021] [Indexed: 11/14/2022] Open
Abstract
CD4+ T cells are crucial in cytomegalovirus (CMV) infection, but their role in infection remains unclear. The heterogeneity and potential functions of CMVpp65-reactivated CD4+ T cell subsets isolated from human peripheral blood, as well as their potential interactions, were analyzed by single-cell RNA-seq and T cell receptor (TCR) sequencing. Tregs comprised the largest population of these reactivated cells, and analysis of Treg gene expression showed transcripts associated with both inflammatory and inhibitory functions. The detailed phenotypes of CMV-reactivated CD4+ cytotoxic T1 (CD4+ CTL1), CD4+ cytotoxic T2 (CD4+ CTL2), and recently activated CD4+ T (Tra) cells were analyzed in single cells. Assessment of the TCR repertoire of CMV-reactivated CD4+ T cells confirmed the clonal expansion of stimulated CD4+ CTL1 and CD4+ CTL2 cells, which share a large number of TCR repertoires. This study provides clues for resolving the functions of CD4+ T cell subsets and their interactions during CMV infection. The specific cell groups defined in this study can provide resources for understanding T cell responses to CMV infection.
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Affiliation(s)
- Menghua Lyu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,BGI-Shenzhen, Shenzhen, China
| | - Shiyu Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,BGI-Shenzhen, Shenzhen, China
| | - Kai Gao
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,BGI-Shenzhen, Shenzhen, China
| | - Longlong Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,BGI-Shenzhen, Shenzhen, China
| | | | - Ya Liu
- BGI-Shenzhen, Shenzhen, China
| | | | - Xiao Liu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China
| | - Bin Li
- Shanghai Institute of Immunology, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Lei Tian
- BGI-Shenzhen, Shenzhen, China.,Department of Neurology, Shenzhen People's Hospital (The First Affiliated Hospital of Southern University of Science and Technology, The Second Clinical Medical College of Jinan University), Shenzhen, China
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Bouchard A, Collin B, Garrido C, Bellaye PS, Kohli E. GARP: A Key Target to Evaluate Tumor Immunosuppressive Microenvironment. BIOLOGY 2021; 10:biology10090836. [PMID: 34571713 PMCID: PMC8470583 DOI: 10.3390/biology10090836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/12/2021] [Indexed: 01/16/2023]
Abstract
Simple Summary Tumors are not only composed of cancer cells but also of various infiltrating cells constituting the tumor microenvironment (TME); all these cells produce growth factors which contribute to tumor progression and invasiveness. Among them, transforming growth factor-β1 (TGF-β1) has been shown to be a potent immunosuppressive cytokine favoring cell proliferation and invasion and to be associated with resistance to anticancer treatments. Glycoprotein-A repetition predominant (GARP) plays a critical role in the activation of TGF-β1 and has been shown to be expressed at the membrane of cancer cells and also of regulatory T cells and platelets in the TME. An increased GARP expression has been shown in a variety of cancers. The objective of this review is to highlight GARP’s expression and function in cancer and to evaluate its potential as a predictive and therapeutic follow-up biomarker that could be assessed, in real time, by molecular imaging. Abstract Glycoprotein-A repetitions predominant (GARP) is the docking receptor for latent transforming growth factor (LTGF-β) and promotes its activation. In cancer, increased GARP expression has been found in many types of cancer. GARP is expressed by regulatory T cells and platelets in the tumor microenvironment (TME) and can be also expressed by tumor cells themselves. Thus, GARP can be widely present in tumors in which it plays a major role in the production of active TGF-β, contributing to immune evasion and cancer progression via the GARP-TGF-β pathway. The objective of this review is to highlight GARP expression and function in cancer and to evaluate the potential of membrane GARP as a predictive and therapeutic follow-up biomarker that could be assessed, in real time, by molecular imaging. Moreover, as GARP can be secreted, a focus will also be made on soluble GARP as a circulating biomarker.
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Affiliation(s)
- Alexanne Bouchard
- Centre George-François Leclerc, Service de Médecine Nucléaire, Plateforme d’Imagerie et de Radiothérapie Précliniques, 1 rue du Professeur Marion, 21079 Dijon, France; (A.B.); (B.C.); (C.G.)
- UMR INSERM/uB/AGROSUP 1231, Labex LipSTIC, Faculty of Health Sciences, Université de Bourgogne Franche-Comté, 21079 Dijon, France
| | - Bertrand Collin
- Centre George-François Leclerc, Service de Médecine Nucléaire, Plateforme d’Imagerie et de Radiothérapie Précliniques, 1 rue du Professeur Marion, 21079 Dijon, France; (A.B.); (B.C.); (C.G.)
- Institut de Chimie Moléculaire de l’Université de Bourgogne, UMR CNRS/uB 6302, Université de Bourgogne Franche-Comté, 21079 Dijon, France
| | - Carmen Garrido
- Centre George-François Leclerc, Service de Médecine Nucléaire, Plateforme d’Imagerie et de Radiothérapie Précliniques, 1 rue du Professeur Marion, 21079 Dijon, France; (A.B.); (B.C.); (C.G.)
- UMR INSERM/uB/AGROSUP 1231, Labex LipSTIC, Faculty of Health Sciences, Université de Bourgogne Franche-Comté, 21079 Dijon, France
| | - Pierre-Simon Bellaye
- Centre George-François Leclerc, Service de Médecine Nucléaire, Plateforme d’Imagerie et de Radiothérapie Précliniques, 1 rue du Professeur Marion, 21079 Dijon, France; (A.B.); (B.C.); (C.G.)
- UMR INSERM/uB/AGROSUP 1231, Labex LipSTIC, Faculty of Health Sciences, Université de Bourgogne Franche-Comté, 21079 Dijon, France
- Correspondence: (P.-S.B.); (E.K.)
| | - Evelyne Kohli
- UMR INSERM/uB/AGROSUP 1231, Labex LipSTIC, Faculty of Health Sciences, Université de Bourgogne Franche-Comté, 21079 Dijon, France
- CHU Dijon, 21079 Dijon, France
- Correspondence: (P.-S.B.); (E.K.)
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Abstract
Regulatory T cells (Tregs) are immunosuppressive immune cells that play an important role in tumor development. Suppression of Treg function is considered to be an effective strategy for cancer therapy. Glycoprotein A repetitions predominant (GARP) has been found on the surface of activated Tregs. GARP has been recently observed in only a few solid tumors including breast, colon, lung cancers, and melanoma. However, its function in cancers remains unknown. Here, we investigated the expression of GARP in human papillary thyroid carcinoma (PTC) and its prognostic significance. In this study, immunohistochemistry was performed to examine the expression of GARP and Foxp3 in 19 human PTC tissues (including 10 cases with and 9 cases without lymph node metastasis) and 20 benign thyroid diseases (including 10 cases with nodular goiter and 10 cases with adenoma). Compared with benign thyroid diseases, we found a significant increase in the expression of GARP in PTC. Increased GARP expression in PTC was positively correlated with increased expression of Foxp3, which is very important for development of Tregs. But, there is no significant association of elevated expression of GARP with lymph node metastasis in PTC. Our results indicate that GARP is implicated in the development of PTC and might be a potential novel target for anticancer therapy. In addition, our findings further support the existence of a positive-feedback loop between GARP and Foxp3.
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Affiliation(s)
- Xiaoxu Zhang
- Department of Anatomy, College of Basic Medical Sciences of Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Miao Guo
- Department of Clinical Laboratory, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Jing Yang
- Department of Pathology, College of Basic Medical Sciences of Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Yuxiao Zheng
- Department of Medical Imaging, Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Yanjie Xiao
- Department of Epidemiology, Public Health College of Jinzhou Medical University, Jinzhou, 121001, Liaoning, China
| | - Wei Liu
- Institute of Biological Anthropology, Jinzhou Medical University, No.40, Section 3, Songpo Road, Linghe District, Jinzhou, 121001, Liaoning, China.
- Liaoning Province Key Laboratory of Chinese Physical Characteristics Research (LPKL-CPCR), Jinzhou, 121001, Liaoning, China.
| | - Fu Ren
- Department of Anatomy, College of Basic Medical Sciences of Jinzhou Medical University, Jinzhou, 121001, Liaoning, China.
- Institute of Biological Anthropology, Jinzhou Medical University, No.40, Section 3, Songpo Road, Linghe District, Jinzhou, 121001, Liaoning, China.
- Liaoning Province Key Laboratory of Chinese Physical Characteristics Research (LPKL-CPCR), Jinzhou, 121001, Liaoning, China.
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Kirkham B, Chaabo K, Hall C, Garrood T, Mant T, Allen E, Vincent A, Vasconcelos JC, Prevost AT, Panayi GS, Corrigall VM. Safety and patient response as indicated by biomarker changes to binding immunoglobulin protein in the phase I/IIA RAGULA clinical trial in rheumatoid arthritis. Rheumatology (Oxford) 2016; 55:1993-2000. [PMID: 27498355 PMCID: PMC5854092 DOI: 10.1093/rheumatology/kew287] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 06/28/2016] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES Binding immunoglobulin protein (BiP) is a human endoplasmic reticulum-resident stress protein. In pre-clinical studies it has anti-inflammatory properties due to the induction of regulatory cells. This randomized placebo-controlled, dose ascending double blind phase I/IIA trial of BiP in patients with active RA, who had failed accepted therapies, had the primary objective of safety. Potential efficacy was measured by DAS28-ESR and changes in biomarkers. METHODS Twenty-four patients with active RA who had failed one or more DMARDs were sequentially assigned to three groups each of eight patients randomly allocated to receive placebo (two patients) or BiP (six patients), 1, 5 or 15 mg. Patients received a single i.v. infusion over 1 h and were observed as inpatients overnight. A 12-week follow-up for clinical, rheumatological and laboratory assessments for safety, efficacy (DAS28-ESR) and biomarker analysis was performed. RESULTS No infusion reactions or serious adverse drug reactions were noted. Adverse events were evenly distributed between placebo and BiP groups with no BiP-related toxicities. Haematological, renal and metabolic parameters showed no drug-related toxicities. Remission was only achieved by patients in the 5 and 15 mg groups, and not patients who received placebo or 1 mg BiP. Good DAS28-ESR responses were achieved in all treatment groups. The BiP responding patients showed significantly lower serum concentrations of CRP, 2 weeks post-infusion compared with pre-infusion levels, and of VEGF and IL-8 from the placebo group. CONCLUSION BiP (⩽15 mg) is safe in patients with active RA. Some patients had clinical and biological improvements in RA activity. BiP merits further study. TRIAL REGISTRATION ISRCTN registry, http://isrctn.com, ISRCTN22288225 and EudraCT, https://eudract.ema.europa.eu, 2011-005831-19.
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Affiliation(s)
- Bruce Kirkham
- Department of Rheumatology, Guys and St Thomas' NHS Foundation Trust Hospital
| | - Khaldoun Chaabo
- Department of Rheumatology, Guys and St Thomas' NHS Foundation Trust Hospital
| | - Christopher Hall
- Academic Department of Rheumatology, Centre for Molecular and Cellular Biology of Inflammation, King's College London
| | - Toby Garrood
- Department of Rheumatology, Guys and St Thomas' NHS Foundation Trust Hospital
| | | | | | - Alexandra Vincent
- Department of Rheumatology, Guys and St Thomas' NHS Foundation Trust Hospital
| | - Joana C Vasconcelos
- Department of Primary Care and Public Health Sciences, King's College London, London, UK
| | - Andrew T Prevost
- Department of Primary Care and Public Health Sciences, King's College London, London, UK
| | - Gabriel S Panayi
- Department of Rheumatology, Guys and St Thomas' NHS Foundation Trust Hospital
- Academic Department of Rheumatology, Centre for Molecular and Cellular Biology of Inflammation, King's College London
| | - Valerie M Corrigall
- Academic Department of Rheumatology, Centre for Molecular and Cellular Biology of Inflammation, King's College London
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Fridrich S, Hahn SA, Linzmaier M, Felten M, Zwarg J, Lennerz V, Tuettenberg A, Stöcker W. How Soluble GARP Enhances TGFβ Activation. PLoS One 2016; 11:e0153290. [PMID: 27054568 PMCID: PMC4824412 DOI: 10.1371/journal.pone.0153290] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 03/25/2016] [Indexed: 11/18/2022] Open
Abstract
GARP (glycoprotein A repetitions predominant) is a cell surface receptor on regulatory T-lymphocytes, platelets, hepatic stellate cells and certain cancer cells. Its described function is the binding and accommodation of latent TGFβ (transforming growth factor), before the activation and release of the mature cytokine. For regulatory T cells it was shown that a knockdown of GARP or a treatment with blocking antibodies dramatically decreases their immune suppressive capacity. This confirms a fundamental role of GARP in the basic function of regulatory T cells. Prerequisites postulated for physiological GARP function include membrane anchorage of GARP, disulfide bridges between the propeptide of TGFβ and GARP and connection of this propeptide to αvβ6 or αvβ8 integrins of target cells during mechanical TGFβ release. Other studies indicate the existence of soluble GARP complexes and a functionality of soluble GARP alone. In order to clarify the underlying molecular mechanism, we expressed and purified recombinant TGFβ and a soluble variant of GARP. Surprisingly, soluble GARP and TGFβ formed stable non-covalent complexes in addition to disulfide-coupled complexes, depending on the redox conditions of the microenvironment. We also show that soluble GARP alone and the two variants of complexes mediate different levels of TGFβ activity. TGFβ activation is enhanced by the non-covalent GARP-TGFβ complex already at low (nanomolar) concentrations, at which GARP alone does not show any effect. This supports the idea of soluble GARP acting as immune modulator in vivo.
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Affiliation(s)
- Sven Fridrich
- Cell and Matrix Biology, Institute of Zoology, JGU Mainz, Mainz, Germany
| | | | - Marion Linzmaier
- Cell and Matrix Biology, Institute of Zoology, JGU Mainz, Mainz, Germany
| | - Matthias Felten
- Cell and Matrix Biology, Institute of Zoology, JGU Mainz, Mainz, Germany
| | - Jenny Zwarg
- University Hospital Mainz, 3rd medical center, Mainz, Germany
| | - Volker Lennerz
- University Hospital Mainz, 3rd medical center, Mainz, Germany
| | | | - Walter Stöcker
- Cell and Matrix Biology, Institute of Zoology, JGU Mainz, Mainz, Germany
- * E-mail:
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6
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Elkord E, Abd Al Samid M, Chaudhary B. Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP. Oncotarget 2015; 6:20026-36. [PMID: 26343373 PMCID: PMC4652984 DOI: 10.18632/oncotarget.4771] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 07/17/2015] [Indexed: 11/25/2022] Open
Abstract
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.
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Affiliation(s)
- Eyad Elkord
- College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
- Biomedical Research Centre, School of Environment & Life Sciences, University of Salford, Manchester, United Kingdom
- Institutes of Cancer, Inflammation & Repair, University of Manchester, Manchester, United Kingdom
| | - May Abd Al Samid
- College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
- Biomedical Research Centre, School of Environment & Life Sciences, University of Salford, Manchester, United Kingdom
| | - Belal Chaudhary
- Biomedical Research Centre, School of Environment & Life Sciences, University of Salford, Manchester, United Kingdom
- University of Cambridge, Cambridge, United Kingdom
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Kalathil S, Lugade AA, Miller A, Iyer R, Thanavala Y. Higher frequencies of GARP(+)CTLA-4(+)Foxp3(+) T regulatory cells and myeloid-derived suppressor cells in hepatocellular carcinoma patients are associated with impaired T-cell functionality. Cancer Res 2013; 73:2435-44. [PMID: 23423978 DOI: 10.1158/0008-5472.can-12-3381] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The extent to which T-cell-mediated immune surveillance is impaired in human cancer remains a question of major importance, given its potential impact on the development of generalized treatments of advanced disease where the highest degree of heterogeneity exists. Here, we report the first global analysis of immune dysfunction in patients with advanced hepatocellular carcinoma (HCC). Using multi-parameter fluorescence-activated cell sorting analysis, we quantified the cumulative frequency of regulatory T cells (Treg), exhausted CD4(+) helper T cells, and myeloid-derived suppressor cells (MDSC) to gain concurrent views on the overall level of immune dysfunction in these inoperable patients. We documented augmented numbers of Tregs, MDSC, PD-1(+)-exhausted T cells, and increased levels of immunosuppressive cytokines in patients with HCC, compared with normal controls, revealing a network of potential mechanisms of immune dysregulation in patients with HCC. In dampening T-cell-mediated antitumor immunity, we hypothesized that these processes may facilitate HCC progression and thwart the efficacy of immunotherapeutic interventions. In testing this hypothesis, we showed that combined regimens to deplete Tregs, MDSC, and PD-1(+) T cells in patients with advanced HCC restored production of granzyme B by CD8(+) T cells, reaching levels observed in normal controls and also modestly increased the number of IFN-γ producing CD4(+) T cells. These clinical findings encourage efforts to restore T-cell function in patients with advanced stage disease by highlighting combined approaches to deplete endogenous suppressor cell populations that can also expand effector T-cell populations.
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Affiliation(s)
- Suresh Kalathil
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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8
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Ménétrier-Caux C, Curiel T, Faget J, Manuel M, Caux C, Zou W. Targeting regulatory T cells. Target Oncol 2012; 7:15-28. [PMID: 22327882 DOI: 10.1007/s11523-012-0208-y] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 01/13/2012] [Indexed: 01/08/2023]
Abstract
Cancers express tumor-associated antigens that should elicit immune response to antagonize the tumor growth, but spontaneous immune rejection of established cancer is rare, suggesting an immunosuppressive environment hindering host antitumor immunity. Among the specific and active tumor-mediated mechanisms, CD4(+)CD25(high) T regulatory cells (Treg) are important mediators of active immune evasion in cancer. In this review, we will discuss Treg subpopulations and the mechanisms of their suppressive functions. Treg depletion improves endogenous antitumor immunity and the efficacy of active immunotherapy in animal models for cancer, suggesting that inhibiting Treg function could also improve the limited successes of human cancer immunotherapy. We will also discuss specific strategies for devising effective cancer immunotherapy targeting Treg.
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Kehrmann J, Zeschnigk M, Buer J, Probst-Kepper M. FOXP3 Expression in GARP-Transduced Helper T Cells Is Not Associated with FOXP3 TSDR Demethylation. ACTA ACUST UNITED AC 2011; 38:287-291. [PMID: 22670117 DOI: 10.1159/000331499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 06/08/2011] [Indexed: 12/15/2022]
Abstract
AIM: Glycoprotein A repetitions predominant (GARP or LRRC32) represents a human regulatory CD4+ CD25(hi) FOXP3+ T (T(reg)) cell-specific receptor that controls FOXP3. Ectopic expression of GARP in helper T (T(h)) 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 T(reg)-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 T(h) cells exhibit constitutive FOXP3 expression and a regulatory phenotype, the FOXP3 TSDR is completely methylated as in naive T(h) cells. GARP-mediated FOXP3 upregulation in T(h) cells is not associated with T(reg)-specific demethylation of the FOXP3 TSDR. CONCLUSION: Although GARP-engineered T(h) cells exhibit stable FOXP3 expression and a phenotypic reprogramming towards T(reg) cells in vitro, these cells do not completely mimic the epigenotype of natural T(reg) cells. Thus, concepts based on the genetic modification of T(h) cells as cellular therapies to treat autoimmune diseases or to control transplantation tolerance should be critically tested before any clinical application.
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Affiliation(s)
- Jan Kehrmann
- Institut für Medizinische Mikrobiologie, Braunschweig, Germany
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10
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Probst-Kepper M, Buer J. FOXP3 and GARP (LRRC32): the master and its minion. Biol Direct 2010; 5:8. [PMID: 20137067 PMCID: PMC2825496 DOI: 10.1186/1745-6150-5-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 02/05/2010] [Indexed: 11/10/2022] Open
Abstract
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.
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Affiliation(s)
- Michael Probst-Kepper
- Institute for Microbiology, Immunology and Hygiene, Städtisches Klinikum Braunschweig gGmbH, Braunschweig, Germany
| | - Jan Buer
- Institute for Medical Microbiology, University Hospital Essen, Essen, Germany
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