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Kumagai S, Itahashi K, Nishikawa H. Regulatory T cell-mediated immunosuppression orchestrated by cancer: towards an immuno-genomic paradigm for precision medicine. Nat Rev Clin Oncol 2024; 21:337-353. [PMID: 38424196 DOI: 10.1038/s41571-024-00870-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2024] [Indexed: 03/02/2024]
Abstract
Accumulating evidence indicates that aberrant signalling stemming from genetic abnormalities in cancer cells has a fundamental role in their evasion of antitumour immunity. Immune escape mechanisms include enhanced expression of immunosuppressive molecules, such as immune-checkpoint proteins, and the accumulation of immunosuppressive cells, including regulatory T (Treg) cells, in the tumour microenvironment. Therefore, Treg cells are key targets for cancer immunotherapy. Given that therapies targeting molecules predominantly expressed by Treg cells, such as CD25 or GITR, have thus far had limited antitumour efficacy, elucidating how certain characteristics of cancer, particularly genetic abnormalities, influence Treg cells is necessary to develop novel immunotherapeutic strategies. Hence, Treg cell-targeted strategies based on the particular characteristics of cancer in each patient, such as the combination of immune-checkpoint inhibitors with molecularly targeted agents that disrupt the immunosuppressive networks mediating Treg cell recruitment and/or activation, could become a new paradigm of cancer therapy. In this Review, we discuss new insights on the mechanisms by which cancers generate immunosuppressive networks that attenuate antitumour immunity and how these networks confer resistance to cancer immunotherapy, with a focus on Treg cells. These insights lead us to propose the concept of 'immuno-genomic precision medicine' based on specific characteristics of cancer, especially genetic profiles, that correlate with particular mechanisms of tumour immune escape and might, therefore, inform the optimal choice of immunotherapy for individual patients.
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Affiliation(s)
- Shogo Kumagai
- Division of Cancer Immunology, Research Institute, National Cancer Center, Tokyo, Japan
- Division of Cancer Immunology, Exploratory Oncology Research & Clinical Trial Center (EPOC), National Cancer Center, Chiba, Japan
- Division of Cellular Signalling, Research Institute, National Cancer Center, Tokyo, Japan
| | - Kota Itahashi
- Division of Cancer Immunology, Research Institute, National Cancer Center, Tokyo, Japan
- Division of Cancer Immunology, Exploratory Oncology Research & Clinical Trial Center (EPOC), National Cancer Center, Chiba, Japan
| | - Hiroyoshi Nishikawa
- Division of Cancer Immunology, Research Institute, National Cancer Center, Tokyo, Japan.
- Division of Cancer Immunology, Exploratory Oncology Research & Clinical Trial Center (EPOC), National Cancer Center, Chiba, Japan.
- Department of Immunology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
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Coexpression of Helios in Foxp3 + Regulatory T Cells and Its Role in Human Disease. DISEASE MARKERS 2021; 2021:5574472. [PMID: 34257746 PMCID: PMC8245237 DOI: 10.1155/2021/5574472] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/15/2021] [Indexed: 12/03/2022]
Abstract
Regulatory T cells (Tregs) expressing the Foxp3 transcription factor are indispensable for the maintenance of immune system homeostasis. Tregs may lose Foxp3 expression or be reprogrammed into cells that produce proinflammatory cytokines, for example, Th1-like Tregs, Th2-like Tregs, Th17-like Tregs, and Tfh-like Tregs. Accordingly, selective therapeutic molecules that manipulate Treg lineage stability and/or functional activity might have the potential to improve aberrant immune responses in human disorders. In particular, the transcription factor Helios has emerged as an important marker and modulator of Tregs. Therefore, the current review focuses on recent findings on the expression, function, and mechanisms of Helios, as well as the patterns of Foxp3+ Tregs coexpressing Helios in various human disorders, in order to explore the potential of Helios for the improvement of many immune-related diseases. The studies were selected from PubMed using the library of the Nanjing Medical University in this review. The findings of the included studies indicate that Helios expression stabilizes the phenotype and function of Foxp3+ Tregs in certain inflammatory environments. Further, Tregs coexpressing Helios and Foxp3 were identified as a specific phenotype of stronger suppressor immune cells in both humans and animal models. Importantly, there is ample evidence that Helios-expressing Foxp3+ Tregs are relevant to various human disorders, including connective tissue diseases, infectious diseases, solid organ transplantation-related immunity, and cancer. Thus, Helios+Foxp3+CD4+ Tregs could be a valuable target in human diseases, and their potential should be explored further in the clinical setting.
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Daneshvar Kakhaki R, Kouchaki E, Dadgostar E, Behnam M, Tamtaji OR, Nikoueinejad H, Akbari H. The correlation of helios and neuropilin-1 frequencies with parkinson disease severity. Clin Neurol Neurosurg 2020; 192:105833. [PMID: 32305590 DOI: 10.1016/j.clineuro.2020.105833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 02/11/2020] [Accepted: 04/02/2020] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Parkinson disease (PD), a neurodegenerative disease, has also some immunologic basis in which several regulatory factors, like Helios and Neuropilin-1 (NRP-1) may show some roles in its pathogenesis. We aimed to evaluate the circulatory frequency of T regulatory cells (Tregs) expressing Helios and NRP-1 in PD. PATIENTS AND METHODS In this case-control study, 83 patients with PD and 83 healthy controls were enrolled. The diagnosis of PD was accomplished in accordance with clinical diagnostic criteria of the UK Parkinson Disease Society Brain Bank. The modified Hoehn and Yahr (H and Y) were used to measure the severity of PD. Flow cytometry was used to evaluate the circulatory frequency of CD4+CD25+Foxp3+Tregs expressing and Helios and NRP-1 in all participants. Also, correlation of H and Y with such frequencies was evaluated. RESULTS Our findings showed that frequency of CD4+CD25+Foxp3+Tregs expressing NRP-1 (P = 0.04) and Helios (P = 0.01) in patients with PD was significantly higher than those in healthy subjects. The frequency of Tregs expressing Helios and NRP-1 showed a negative correlation with H and Y criteria and disease duration. Multiple linear regression analysis indicated that the severity of PD is the only effective factor on the frequency of CD4+CD25+Foxp3+NRP-1+Tregs (P = 0.012) and CD4+CD25+FoxP3+ Helios + Tregs (P = 0.038). CONCLUSION Our study showed that the increased frequency of Tregs expressing Helios and NRP-1 is associated with the severity of PD.
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Affiliation(s)
- Reza Daneshvar Kakhaki
- Autoimmune Diseases Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | - Ebrahim Kouchaki
- Physiology Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
| | | | - Mohammad Behnam
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
| | - Omid Reza Tamtaji
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.
| | - Hassan Nikoueinejad
- Department of Immunology, Baqiyatallah University of Medical Sciences, Tehran, Iran; Nephrology and Urology Research Center, Baqiyatallah University of Medical Sciences, Baqiyatallah Hospital, Mollasadra Ave., Vanak Sq., P.O. Box: 19395-5487, Tehran, Iran.
| | - Hossein Akbari
- Department of Biostatistics and Public Health, Faculty of Health, Kashan University of Medical Sciences, Kashan, Iran
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Scolopendra subspinipes mutilans L. Koch Ameliorates Rheumatic Heart Disease by Affecting Relative Percentages of CD4 +CD25 +FoxP3 Treg and CD4 +IL17 T Cells. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:4674190. [PMID: 31379962 PMCID: PMC6662451 DOI: 10.1155/2019/4674190] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 05/28/2019] [Indexed: 01/09/2023]
Abstract
(Scolopendra subspinipes mutilans L. Koch. (SSLK) helps reduce the risk of coronary heart disease (CHD) but its effects on rheumatic heart disease (RHD) patients remain unclear. 80 RHD patients were recruited and randomly assigned into SG (to receive SSLK treatment) and CG (to receive placebo) groups, and the intervention lasted for 3 months. The following cardiac indexes were measured, including mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), blood lactate, fatigue, shortness of breath, palpitation, and chest pain. ELISA kits were used to analyze creatine kinase isoenzyme (CK-MB), serum troponin T (cTnT), CRP, IL-1β, IL-6, and TNF-α, malondialdehyde (MDA), and superoxide dismutase (SOD). Relative percentages of CD4+CD25+FoxP3 regulatory (Treg) and CD4+IL-17 T cells were measured using flow cytometry. After 3-month therapy, SSLK intervention improved MAP, HR, CVP, fatigue, palpitation, and shortness breath of CHD patients, reduced the levels of blood lactate, CK-MB, cTnT, CRP, IL-1β, IL-6, TNF-α, MDA, and increased SOD level (p < 0.05). Meanwhile, SSLK treatment increased the percentages of CD4+CD25+FoxP3 Treg cells and reduced relative percentages of CD4+IL-17 T cells in a dose-dependent way (p < 0.05). Relative percentage of CD4+CD25+FoxP3 Treg cells had negative relationship while CD4+IL17 T cells had positive relationship with CK-MB, cTnT, CRP, and TNF-a (p < 0.01). SSLK ameliorated RHD by affecting the balance of CD4+CD25+FoxP3 Treg and CD4+IL17 T cells.
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Abd Al Samid M, Chaudhary B, Khaled YS, Ammori BJ, Elkord E. Combining FoxP3 and Helios with GARP/LAP markers can identify expanded Treg subsets in cancer patients. Oncotarget 2017; 7:14083-94. [PMID: 26885615 PMCID: PMC4924699 DOI: 10.18632/oncotarget.7334] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/29/2016] [Indexed: 12/14/2022] Open
Abstract
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.
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Affiliation(s)
- May Abd Al Samid
- Biomedical Research Centre, School of Environment and Life Sciences, University of Salford, Manchester, United Kingdom.,College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Belal Chaudhary
- Biomedical Research Centre, School of Environment and Life Sciences, University of Salford, Manchester, United Kingdom
| | - Yazan S Khaled
- Institute of Cancer Sciences, University of Manchester, Manchester, United Kingdom
| | - Basil J Ammori
- Institute of Cancer Sciences, University of Manchester, Manchester, United Kingdom
| | - Eyad Elkord
- Biomedical Research Centre, School of Environment and Life Sciences, University of Salford, Manchester, United Kingdom.,College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Institute of Cancer Sciences, University of Manchester, Manchester, United Kingdom
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Downs-Canner S, Berkey S, Delgoffe GM, Edwards RP, Curiel T, Odunsi K, Bartlett DL, Obermajer N. Suppressive IL-17A +Foxp3 + and ex-Th17 IL-17A negFoxp3 + T reg cells are a source of tumour-associated T reg cells. Nat Commun 2017; 8:14649. [PMID: 28290453 PMCID: PMC5355894 DOI: 10.1038/ncomms14649] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 01/20/2017] [Indexed: 01/05/2023] Open
Abstract
Th17 and regulatory T (Treg) cells are integral in maintaining immune homeostasis and Th17–Treg imbalance is associated with inflammatory immunosuppression in cancer. Here we show that Th17 cells are a source of tumour-induced Foxp3+ cells. In addition to natural (n)Treg and induced (i)Treg cells that develop from naive precursors, suppressive IL-17A+Foxp3+ and ex-Th17 Foxp3+ cells are converted from IL-17A+Foxp3neg cells in tumour-bearing mice. Metabolic phenotyping of Foxp3-expressing IL-17A+, ex-Th17 and iTreg cells demonstrates the dissociation between the metabolic fitness and the suppressive function of Foxp3-expressing Treg cell subsets. Although all Foxp3-expressing subsets are immunosuppressive, glycolysis is a prominent metabolic pathway exerted only by IL-17A+Foxp3+ cells. Transcriptome analysis and flow cytometry of IL-17A+Foxp3+ cells indicate that Folr4, GARP, Itgb8, Pglyrp1, Il1rl1, Itgae, TIGIT and ICOS are Th17-to-Treg cell transdifferentiation-associated markers. Tumour-associated Th17-to-Treg cell conversion identified here provides insights for targeting the dynamism of Th17–Treg cells in cancer immunotherapy. Th17 cells can transdifferentiate into regulatory T (Treg) cells. Here the authors characterize tumour-driven Th17-to-Treg cell transdifferentiation and identify potential cancer therapy targets.
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Affiliation(s)
- Stephanie Downs-Canner
- Department of Surgical Oncology, University of Pittsburgh, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Sara Berkey
- Department of Surgical Oncology, University of Pittsburgh, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Greg M Delgoffe
- University of Pittsburgh Cancer Institute, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA.,Tumour Microenvironment Center, Hillman Cancer Center, University of Pittsburgh, 5115 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA.,Magee-Womens Research Institute Ovarian Cancer Center of Excellence, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Robert P Edwards
- University of Pittsburgh Cancer Institute, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA.,Magee-Womens Research Institute Ovarian Cancer Center of Excellence, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA.,Peritoneal/Ovarian Cancer Specialty Care Center, Pittsburgh, Pennsylvania 15213, USA
| | - Tyler Curiel
- UT Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Kunle Odunsi
- Departments of Gynecologic Oncology and Immunology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, New York 14263, USA
| | - David L Bartlett
- Department of Surgical Oncology, University of Pittsburgh, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Nataša Obermajer
- Department of Surgical Oncology, University of Pittsburgh, 5150 Centre Avenue, Pittsburgh, Pennsylvania 15213, USA
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7
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Fan Y, Lu D. The Ikaros family of zinc-finger proteins. Acta Pharm Sin B 2016; 6:513-521. [PMID: 27818917 PMCID: PMC5071621 DOI: 10.1016/j.apsb.2016.06.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 12/21/2022] Open
Abstract
Ikaros represents a zinc-finger protein family important for lymphocyte development and certain other physiological processes. The number of family members is large, with alternative splicing producing various additional isoforms from each of the five homologous genes in the family. The functional forms of Ikaros proteins could be even more diverse due to protein–protein interactions readily established between family members. Emerging evidence suggests that targeting Ikaros proteins is feasible and effective in therapeutic applications, although the exact roles of Ikaros proteins remain elusive within the intricate regulatory networks in which they are involved. In this review we collect existing knowledge as to the functions, regulatory pathways, and molecular mechanisms of this family of proteins in an attempt to gain a better understanding through the comparison of activities and interactions among family members.
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8
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Abstract
The critical contribution of CD4+CD25+Foxp3+ T-regulatory cells (Treg) to immune suppression in the tumor microenvironment is well-established. Whereas the mechanisms that drive the generation and accumulation of Treg in tumors have been an active area of study, the information on their origin and population dynamics remains limited. In this review, we discuss the ontogeny of tumor-associated Treg in light of the recently identified lineage markers.
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Affiliation(s)
- Qingsheng Li
- a Department of Microbiology and Immunology , School of Medicine, University of Louisville , Louisville , KY , USA
| | - Nejat K Egilmez
- a Department of Microbiology and Immunology , School of Medicine, University of Louisville , Louisville , KY , USA
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9
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Beziaud L, Mansi L, Ravel P, Marie-Joseph EL, Laheurte C, Rangan L, Bonnefoy F, Pallandre JR, Boullerot L, Gamonet C, Vrecko S, Queiroz L, Maurina T, Mouillet G, Hon TNT, Curtit E, Royer B, Gaugler B, Bayry J, Tartour E, Thiery-Vuillemin A, Pivot X, Borg C, Godet Y, Adotévi O. Rapalogs Efficacy Relies on the Modulation of Antitumor T-cell Immunity. Cancer Res 2016; 76:4100-12. [DOI: 10.1158/0008-5472.can-15-2452] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 04/27/2016] [Indexed: 11/16/2022]
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10
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Muto S, Owada Y, Inoue T, Watanabe Y, Yamaura T, Fukuhara M, Okabe N, Matsumura Y, Hasegawa T, Osugi J, Hoshino M, Higuchi M, Suzuki H, Gotoh M. Clinical significance of expanded Foxp3⁺ Helios⁻ regulatory T cells in patients with non-small cell lung cancer. Int J Oncol 2015; 47:2082-90. [PMID: 26460798 PMCID: PMC4665856 DOI: 10.3892/ijo.2015.3196] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 09/17/2015] [Indexed: 12/12/2022] Open
Abstract
The functions of different regulatory T cell (Treg) types in cancer progression are unclear. Recently, expression of the transcription factor Helios was proposed as a marker for natural (non-induced) Tregs. The present study investigated the clinical significance of Helios expression in patients with non-small cell lung cancer (NSCLC). We enrolled 64 patients with NSCLC, of whom 45 were treated surgically and 19 received chemotherapy because of advanced/recurrent disease. Their peripheral blood mononuclear cells were examined by flow cytometry. From the 45 surgery patients, we matched 9 patients with recurrent disease with 9 stage-matched patients without recurrence (n=18), compared their specimens immunohistochemically for tumor infiltrating lymphocytes (TILs) and analyzed these data against clinicopathological factors. Helios expression in Foxp3+ Tregs was 47.5±13.3% in peripheral blood and 18.1±13.4% in tumor specimens. Percentage of Helios− Tregs among CD4+ T cells were significantly higher in the cancer patients (2.4%), especially those with stage IA disease (2.6%) than in healthy donors (1.5%; P<0.001). Patients with low levels of Helios expression in Tregs among their TILs had significantly poorer survival (P=0.038). Helios− Tregs may affect immune suppression, even in early stage NSCLC; they could also be a useful prognostic biomarker in patients with NSCLC, and possibly a novel cancer immunotherapy target.
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Affiliation(s)
- Satoshi Muto
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Yuki Owada
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Takuya Inoue
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Yuzuru Watanabe
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Takumi Yamaura
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Mitsuro Fukuhara
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Naoyuki Okabe
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Yuki Matsumura
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Takeo Hasegawa
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Jun Osugi
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Mika Hoshino
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Mitsunori Higuchi
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Hiroyuki Suzuki
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Mitsukazu Gotoh
- Department of Regenerative Surgery, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
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11
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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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12
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Halvorsen EC, Mahmoud SM, Bennewith KL. Emerging roles of regulatory T cells in tumour progression and metastasis. Cancer Metastasis Rev 2015; 33:1025-41. [PMID: 25359584 DOI: 10.1007/s10555-014-9529-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The metastasis of cancer is a complex and life-threatening process that is only partially understood. Immune suppressive cells are recognized as important contributors to tumour progression and may also promote the development and growth of tumour metastases. Specifically, regulatory T cells (Tregs) have been found to promote primary tumour progression, and emerging pre-clinical data suggests that Tregs may promote metastasis and metastatic tumour growth. While the precise role that Tregs play in metastatic progression is understudied, recent findings have indicated that by suppressing innate and adaptive anti-tumour immunity, Tregs may shield tumour cells from immune detection, and thereby allow tumour cells to survive, proliferate and acquire characteristics that facilitate dissemination. This review will highlight our current understanding of Tregs in metastasis, including an overview of pre-clinical findings and discussion of clinical data regarding Tregs and therapeutic outcome. Evolving strategies to directly ablate Tregs or to inhibit their function will also be discussed. Improving our understanding of how Tregs may influence tumour metastasis may lead to novel treatments for metastatic cancer.
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Affiliation(s)
- Elizabeth C Halvorsen
- Department of Integrative Oncology, British Columbia Cancer Agency, 9-202, 675 West 10th Avenue, Vancouver, British Columbia, V5Z 1L3, Canada
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13
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The role of regulatory T cells and microglia in glioblastoma-associated immunosuppression. J Neurooncol 2015; 123:405-12. [PMID: 26123363 DOI: 10.1007/s11060-015-1849-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 06/08/2015] [Indexed: 01/09/2023]
Abstract
Cell-mediated suppression of anti-tumor immunity is multifactorial in patients with cancer, and recent studies have focused on several distinct cellular agents that are associated with this phenomenon. This review will focus on the potential role of regulatory T cells (Tregs) and microglia in the suppression of cellular immunity observed in patients with glioblastoma. We discuss the ontogeny, basic biology, evidence for activity, and potential clinical options for targeting Tregs and microglia as part of immunotherapy in affected patients.
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14
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Karimi S, Chattopadhyay S, Chakraborty NG. Manipulation of regulatory T cells and antigen-specific cytotoxic T lymphocyte-based tumour immunotherapy. Immunology 2015; 144:186-96. [PMID: 25243729 DOI: 10.1111/imm.12387] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 09/12/2014] [Accepted: 09/16/2014] [Indexed: 12/16/2022] Open
Abstract
The most potent killing machinery in our immune system is the cytotoxic T lymphocyte (CTL). Since the possibility for self-destruction by these cells is high, many regulatory activities exist to prevent autoimmune destruction by these cells. A tumour (cancer) grows from the cells of the body and is tolerated by the body's immune system. Yet, it has been possible to generate tumour-associated antigen (TAA) -specific CTL that are also self-antigen specific in vivo, to achieve a degree of therapeutic efficacy. Tumour-associated antigen-specific T-cell tolerance through pathways of self-tolerance generation represents a significant challenge to successful immunotherapy. CD4(+) CD25(+) FoxP3(+) T cells, referred to as T regulatory (Treg) cells, are selected in the thymus as controllers of the anti-self repertoire. These cells are referred to as natural T regulatory (nTreg) cells. According to the new consensus (Nature Immunology 2013; 14:307-308) these cells are to be termed as (tTreg). There is another class of CD4(+) Treg cells also involved in regulatory function in the periphery, also phenotypically CD4(+) CD25(±) , classified as induced Treg (iTreg) cells. These cells are to be termed as peripherally induced Treg (pTreg) cells. In vitro-induced Treg cells with suppressor function should be termed as iTreg. These different Treg cells differ in their requirements for activation and in their mode of action. The current challenges are to determine the degree of specificity of these Treg cells in recognizing the same TAA as the CTL population and to circumvent their regulatory constraints so as to achieve robust CTL responses against cancer.
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Affiliation(s)
- Shirin Karimi
- Department of Medicine, University of Connecticut Health Center, Farmington, CT, USA
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15
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Persa E, Balogh A, Sáfrány G, Lumniczky K. The effect of ionizing radiation on regulatory T cells in health and disease. Cancer Lett 2015; 368:252-61. [PMID: 25754816 DOI: 10.1016/j.canlet.2015.03.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 03/02/2015] [Accepted: 03/03/2015] [Indexed: 02/07/2023]
Abstract
Treg cells are key elements of the immune system which are responsible for the immune suppressive phenotype of cancer patients. Interaction of Treg cells with conventional anticancer therapies might fundamentally influence cancer therapy response rates. Radiotherapy, apart from its direct tumor cell killing potential, has a contradictory effect on the antitumor immune response: it augments certain immune parameters, while it depresses others. Treg cells are intrinsically radioresistant due to reduced apoptosis and increased proliferation, which leads to their systemic and/or intratumoral enrichment. While physiologically Treg suppression is not enhanced by irradiation, this is not the case in a tumorous environment, where Tregs acquire a highly suppressive phenotype, which is further increased by radiotherapy. This is the reason why the interest for combined radiotherapy and immunotherapy approaches focusing on the abrogation of Treg suppression has increased in cancer therapy in the last few years. Here we summarize the basic mechanisms of Treg radiation response both in healthy and cancerous environments and discuss Treg-targeted pre-clinical and clinical immunotherapy approaches used in combination with radiotherapy. Finally, the discrepant findings regarding the predictive value of Tregs in therapy response are also reviewed.
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Affiliation(s)
- Eszter Persa
- Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene, Budapest, Hungary
| | - Andrea Balogh
- Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene, Budapest, Hungary
| | - Géza Sáfrány
- Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene, Budapest, Hungary
| | - Katalin Lumniczky
- Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene, Budapest, Hungary.
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16
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Chaudhary B, Elkord E. Novel expression of Neuropilin 1 on human tumor-infiltrating lymphocytes in colorectal cancer liver metastases. Expert Opin Ther Targets 2014; 19:147-61. [PMID: 25351619 DOI: 10.1517/14728222.2014.977784] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Neuropilin 1 (NRP1) is a transmembrane protein with diverse roles in physiological and pathological settings. NRP1 expression has been reported on T cells in inflammatory microenvironments and in secondary lymphoid tissue. Tumor-infiltrating lymphocytes (TILs) play an important role in cancer prognosis. In this study, we investigated NRP1 expression on TILs and peripheral blood mononuclear cells (PBMCs) from colorectal cancer liver metastases (LI/CRC). METHODS TILs from LI/CRC and PBMCs from healthy donors and patients were analyzed for expression of NRP1, in addition to other Treg-related markers. PBMCs were co-cultured in vitro with tumor tissue and analyzed for NRP1 expression. RESULTS We report for the first time that NRP1 is highly expressed on CD3(+)CD4(+) TILs compared to PBMCs. NRP1 expression correlated closely with CD25 expression in TILs. NRP1 was expressed on both Helios(+) and Helios(-) FoxP3-expressing Tregs and on a FoxP3(-)Helios(-) T cell subset. It was also induced on PBMCs following in vitro co-culture with tumor tissue. CONCLUSIONS NRP1 is upregulated on TILs and can be induced on PBMCs by tumor tissue. Further studies are warranted to define the function of NRP1 on human TILs. As a therapeutic target, NRP1 may allow selective targeting of TIL subsets including suppressive Tregs.
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Affiliation(s)
- Belal Chaudhary
- United Arab Emirates University, College of Medicine and Health Sciences , PO Box 17666, Al Ain , UAE +971 37137527 ; +971 37671966 ; ;
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17
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Chaudhary B, Abd Al Samid M, al-Ramadi BK, Elkord E. Phenotypic alterations, clinical impact and therapeutic potential of regulatory T cells in cancer. Expert Opin Biol Ther 2014; 14:931-45. [DOI: 10.1517/14712598.2014.900539] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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18
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Olson BM, Sullivan JA, Burlingham WJ. Interleukin 35: a key mediator of suppression and the propagation of infectious tolerance. Front Immunol 2013; 4:315. [PMID: 24151492 PMCID: PMC3798782 DOI: 10.3389/fimmu.2013.00315] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 09/18/2013] [Indexed: 12/31/2022] Open
Abstract
The importance of regulatory T cells (Tregs) in balancing the effector arm of the immune system is well documented, playing a central role in preventing autoimmunity, facilitating graft tolerance following organ transplantation, and having a detrimental impact on the development of anti-tumor immunity. These regulatory responses use a variety of mechanisms to mediate suppression, including soluble factors. While IL-10 and TGF-β are the most commonly studied immunosuppressive cytokines, the recently identified IL-35 has been shown to have potent suppressive function in vitro and in vivo. Furthermore, not only does IL-35 have the ability to directly suppress effector T cell responses, it is also able to expand regulatory responses by propagating infectious tolerance and generating a potent population of IL-35-expressing inducible Tregs. In this review, we summarize research characterizing the structure and function of IL-35, examine its role in disease, and discuss how it can contribute to the induction of a distinct population of inducible Tregs.
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Affiliation(s)
- Brian M Olson
- Department of Medicine, Carbone Cancer Center, University of Wisconsin , Madison, WI , USA
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19
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Dhamne C, Chung Y, Alousi AM, Cooper LJN, Tran DQ. Peripheral and thymic foxp3(+) regulatory T cells in search of origin, distinction, and function. Front Immunol 2013; 4:253. [PMID: 23986762 PMCID: PMC3753660 DOI: 10.3389/fimmu.2013.00253] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/12/2013] [Indexed: 12/15/2022] Open
Abstract
Over the past decade, much has been learnt and much more to discover about Foxp3(+) regulatory T cells (Tregs). Initially, it was thought that Tregs were a unique entity that originates in the thymus. It is now recognized that there is a fraternal twin sibling that is generated in the periphery. The difficulty is in the distinction between these two subsets. The ability to detect, monitor, and analyze these two subsets in health and disease will provide invaluable insights into their functions and purposes. The plasticity and mechanisms of action can be unique and not overlapping within these subsets. Therefore, the therapeutic targeting of a particular subset of Tregs might be more efficacious. In the past couple of years, a vast amount of data have provided a better understanding of the cellular and molecular components essential for their development and stability. Many studies are implicating their preferential involvement in certain diseases and immunologic tolerance. However, it remains controversial as to whether any phenotypic markers have been identified that can differentiate thymic versus peripheral Tregs. This review will address the validity and controversy regarding Helios, Lap/Garp and Neuropilin-1 as markers of thymic Tregs. It also will discuss updated information on distinguishing features of these two subsets and their critical roles in maternal-fetal tolerance and transplantation.
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Affiliation(s)
- Chetan Dhamne
- Department of Paediatrics, University Children’s Medical Institute, National University Hospital, Singapore
| | - Yeonseok Chung
- Institute of Molecular Medicine, Center for Immunology and Autoimmune Diseases, UTHealth, Houston, TX, USA
| | - Amin Majid Alousi
- Department of Pediatrics Patient Care, Division of Pediatrics, M.D. Anderson Cancer Center, Houston, TX, USA
| | - Laurence J. N. Cooper
- Department of Stem Cell Transplant and Cellular Therapy, Division of Cancer Medicine, M.D. Anderson Cancer Center, Houston, TX, USA
| | - Dat Quoc Tran
- Department of Pediatrics, Divisions of Allergy/Immunology, Pediatric Research Center, UTHealth, Houston, TX, USA
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20
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Burocchi A, Colombo MP, Piconese S. Convergences and divergences of thymus- and peripherally derived regulatory T cells in cancer. Front Immunol 2013; 4:247. [PMID: 23986759 PMCID: PMC3753661 DOI: 10.3389/fimmu.2013.00247] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 08/08/2013] [Indexed: 12/18/2022] Open
Abstract
The expansion of regulatory T cells (Treg) is a common event characterizing the vast majority of human and experimental tumors and it is now well established that Treg represent a crucial hurdle for a successful immunotherapy. Treg are currently classified, according to their origin, into thymus-derived Treg (tTreg) or peripherally induced Treg (pTreg) cells. Controversy exists over the prevalent mechanism accounting for Treg expansion in tumors, since both tTreg proliferation and de novo pTreg differentiation may occur. Since tTreg and pTreg are believed as preferentially self-specific or broadly directed to non-self and tumor-specific antigens, respectively, the balance between tTreg and pTreg accumulation may impact on the repertoire of antigen specificities recognized by Treg in tumors. The prevalence of tTreg or pTreg may also affect the outcome of immunotherapies based on tumor-antigen vaccination or Treg depletion. The mechanisms dictating pTreg induction or tTreg expansion/stability are a matter of intense investigation and the most recent results depict a complex landscape. Indeed, selected Treg subsets may display peculiar characteristics in terms of stability, suppressive function, and cytokine production, depending on microenvironmental signals. These features may be differentially distributed between pTreg and tTreg and may significantly affect the possibility of manipulating Treg in cancer therapy. We propose here that innovative immunotherapeutic strategies may be directed at diverting unstable/uncommitted Treg, mostly enriched in the pTreg pool, into tumor-specific effectors, while preserving systemic immune tolerance ensured by self-specific tTreg.
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Affiliation(s)
- Alessia Burocchi
- Molecular Immunology Unit, Department of Experimental Medicine, Fondazione IRCCS "Istituto Nazionale Tumori," Milan , Italy
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21
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Simonetta F, Bourgeois C. CD4+FOXP3+ Regulatory T-Cell Subsets in Human Immunodeficiency Virus Infection. Front Immunol 2013; 4:215. [PMID: 23908654 PMCID: PMC3727053 DOI: 10.3389/fimmu.2013.00215] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 07/13/2013] [Indexed: 01/29/2023] Open
Abstract
The role of CD4+FOXP3+ regulatory T cells (Treg) in human immunodeficiency virus (HIV) infection has been an area of intensive investigation and remains a matter of ardent debate. Investigation and interpretation suffered from uncertainties concerning Treg quantification. Firstly, Treg quantification and function in HIV infection remain controversial in part because of the lack of reliable and specific markers to identify human Tregs. Secondly, analyzing Treg percentages or absolute numbers led to apparent discrepancies that are now solved: it is now commonly accepted that Treg are targets of HIV infection, but are preferentially preserved compared to conventional CD4 T cells. Moreover, the duality of immune defects associated to HIV infection, i.e., low grade chronic inflammation and defects in HIV-specific responses also casts doubts on the potential impact of Treg on HIV infection. Tregs may be beneficial or/and detrimental to the control of HIV infection by suppressing chronic inflammation or HIV-specific responses respectively. Indeed both effects of Treg suppression have been described in HIV infection. The discovery in recent years of the existence of phenotypically and functionally distinct human CD4+FOXP3+ Treg subsets may provide a unique opportunity to reconcile these contrasting results. It is tempting to speculate that different Treg subsets exert these different suppressive effects. This review summarizes available data concerning Treg fate during HIV infection when considering Treg globally or as subsets. We discuss how the identification of naïve and effector Treg subsets modulates our understanding of Treg biology during HIV infection and the potential impact of HIV infection on mechanisms governing peripheral differentiation of adaptive Tregs.
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Affiliation(s)
- Federico Simonetta
- INSERM, U1012 , Le Kremlin-Bicêtre , France ; Université Paris-SUD, UMR-S1012 , Le Kremlin-Bicêtre , France ; Division of Immunology and Allergy, Department of Internal Medicine, Geneva University Hospitals , Geneva , Switzerland
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22
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Whiteside TL, Jackson EK. Adenosine and prostaglandin e2 production by human inducible regulatory T cells in health and disease. Front Immunol 2013; 4:212. [PMID: 23898333 PMCID: PMC3722515 DOI: 10.3389/fimmu.2013.00212] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 07/11/2013] [Indexed: 12/20/2022] Open
Abstract
Regulatory T cells (Treg) play a key role in maintaining the balance of immune responses in human health and in disease. Treg come in many flavors and can utilize a variety of mechanisms to modulate immune responses. In cancer, inducible (i) or adaptive Treg expand, accumulate in tissues and peripheral blood of patients, and represent a functionally prominent component of CD4+ T lymphocytes. Phenotypically and functionally, iTreg are distinct from natural (n) Treg. A subset of iTreg expressing ectonucleotidases CD39 and CD73 is able to hydrolyze ATP to 5′-AMP and adenosine (ADO) and thus mediate suppression of those immune cells which express ADO receptors. iTreg can also produce prostaglandin E2 (PGE2). The mechanisms responsible for iTreg-mediated suppression involve binding of ADO and PGE2 produced by iTreg to their respective receptors expressed on T effector cells (Teff), leading to the up-regulation of adenylate cyclase and cAMP activities in Teff and to their functional inhibition. The potential for regulating these mechanisms by the use of pharmacologic inhibitors to relieve iTreg-mediated suppression in cancer suggests the development of therapeutic strategies targeting the ADO and PGE2 pathways.
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Affiliation(s)
- Theresa L Whiteside
- Department of Pathology, University of Pittsburgh Cancer Institute , Pittsburgh, PA , USA
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23
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Abstract
CD4+Foxp3+ T regulatory (Treg) cells control many facets of immune responses ranging from autoimmune diseases, to inflammatory conditions, and cancer in an attempt to maintain immune homeostasis. Natural Treg (nTreg) cells develop in the thymus and constitute a critical arm of active mechanisms of peripheral tolerance particularly to self antigens. A growing body of knowledge now supports the existence of induced Treg (iTreg) cells which may derive from a population of conventional CD4+ T cells. The fork-head transcription factor (Foxp3) typically is expressed by natural CD4+ Treg cells, and thus serves as a marker to definitively identify these cells. On the contrary, there is less consensus on what constitutes iTreg cells as their precise definition has been somewhat elusive. This is in part due to their distinct phenotypes which are shaped by exposure to certain inflammatory or "assault" signals stemming from the underlying immune disorder. The "policing" activity of Treg cells tends to be uni-directional in several pathological conditions. On one end of the spectrum, Treg cell suppressive activity is beneficial by curtailing T cell response against self-antigens and allergens thus preventing autoimmune diseases and allergies. On the other end however, their inhibitory roles in limiting immune response against pseudo-self antigens as in tumors often culminates into negative outcomes. In this review, we focus on this latter aspect of Treg cell immunobiology by highlighting the involvement of nTreg cells in various animal models and human tumors. We further discuss iTreg cells, relationship with their natural counterpart, and potential co-operation between the two in modulating immune response against tumors. Lastly, we discuss studies focusing on these cells as targets for improving anti-tumor immunity.
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Affiliation(s)
- Dennis O Adeegbe
- Experimental Immunology, Immunology Frontier Research Center, Osaka University , Suita , Japan
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24
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Ondondo B, Jones E, Godkin A, Gallimore A. Home sweet home: the tumor microenvironment as a haven for regulatory T cells. Front Immunol 2013; 4:197. [PMID: 23874342 PMCID: PMC3712544 DOI: 10.3389/fimmu.2013.00197] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 07/03/2013] [Indexed: 01/28/2023] Open
Abstract
CD4+Foxp3+ regulatory T cells (Tregs) have a fundamental role in maintaining immune balance by preventing autoreactivity and immune-mediated pathology. However this role of Tregs extends to suppression of anti-tumor immune responses and remains a major obstacle in the development of anti-cancer vaccines and immunotherapies. This feature of Treg activity is exacerbated by the discovery that Treg frequencies are not only elevated in the blood of cancer patients, but are also significantly enriched within tumors in comparison to other sites. These observations have sparked off the quest to understand the processes through which Tregs become elevated in cancer-bearing hosts and to identify the specific mechanisms leading to their accumulation within the tumor microenvironment. This manuscript reviews the evidence for specific mechanisms of intra-tumoral Treg enrichment and will discuss how this information may be utilized for the purpose of manipulating the balance of tumor-infiltrating T cells in favor of anti-tumor effector cells.
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Affiliation(s)
- Beatrice Ondondo
- Nuffield Department of Medicine, The Jenner Institute (ORCRB), University of Oxford , Oxford , UK
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25
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Adeegbe DO, Nishikawa H. Natural and induced T regulatory cells in cancer. Front Immunol 2013; 4:190. [PMID: 23874336 PMCID: PMC3708155 DOI: 10.3389/fimmu.2013.00190] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 06/27/2013] [Indexed: 12/13/2022] Open
Abstract
CD4+Foxp3+ T regulatory (Treg) cells control many facets of immune responses ranging from autoimmune diseases, to inflammatory conditions, and cancer in an attempt to maintain immune homeostasis. Natural Treg (nTreg) cells develop in the thymus and constitute a critical arm of active mechanisms of peripheral tolerance particularly to self antigens. A growing body of knowledge now supports the existence of induced Treg (iTreg) cells which may derive from a population of conventional CD4+ T cells. The fork-head transcription factor (Foxp3) typically is expressed by natural CD4+ Treg cells, and thus serves as a marker to definitively identify these cells. On the contrary, there is less consensus on what constitutes iTreg cells as their precise definition has been somewhat elusive. This is in part due to their distinct phenotypes which are shaped by exposure to certain inflammatory or “assault” signals stemming from the underlying immune disorder. The “policing” activity of Treg cells tends to be uni-directional in several pathological conditions. On one end of the spectrum, Treg cell suppressive activity is beneficial by curtailing T cell response against self-antigens and allergens thus preventing autoimmune diseases and allergies. On the other end however, their inhibitory roles in limiting immune response against pseudo-self antigens as in tumors often culminates into negative outcomes. In this review, we focus on this latter aspect of Treg cell immunobiology by highlighting the involvement of nTreg cells in various animal models and human tumors. We further discuss iTreg cells, relationship with their natural counterpart, and potential co-operation between the two in modulating immune response against tumors. Lastly, we discuss studies focusing on these cells as targets for improving anti-tumor immunity.
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Affiliation(s)
- Dennis O Adeegbe
- Experimental Immunology, Immunology Frontier Research Center, Osaka University , Suita , Japan
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26
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Polimeno M, Napolitano M, Costantini S, Portella L, Esposito A, Capone F, Guerriero E, Trotta A, Zanotta S, Pucci L, Longo N, Perdonà S, Pignata S, Castello G, Scala S. Regulatory T cells, interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), CXCL10, CXCL11, epidermal growth factor (EGF) and hepatocyte growth factor (HGF) as surrogate markers of host immunity in patients with renal cell carcinoma. BJU Int 2013; 112:686-96. [PMID: 23495770 DOI: 10.1111/bju.12068] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To identify a phenotype that could be informative and prognostic in patients with renal cell carcinoma (RCC) peripheral blood was evaluated for TH1, TH2, regulatory T cells (Tregs), natural killer (NK) and NKT cells and for cytokines/chemokines. PATIENTS AND METHODS Peripheral blood from 77 patients with RCC and 40 healthy controls was evaluated by flow cytometry using monoclonal antibodies against CD4, CD25, FoxP3, CD45RA, CD45RO, CD152, CD184, CD279, CD3, CD16, CD56, CD161, CD158a, CD4, CD26, CD30, CD183 and CD184. A concomitant evaluation of 38 molecules was conducted in patients' serum using a multiplex biometric ELISA-based immunoassay. RESULTS The number of NK cells CD3⁻/CD16⁺, CD3⁻/CD16⁺/CD161⁺ (NK) and CD3⁻/CD16⁺/CD161⁺/CD158a⁺ (NK- Kir 2+) was greater in the patients with RCC (P < 0.05); and the number of Treg cells CD4⁺/CD25(high+)/FOXP3⁺ and the subset CD4⁺/CD25(high+)/FOXP3⁺/CD45RA⁺ (naïve) and CD45R0⁺(memory) cells, were greater in the patients with RCC (P < 0.001). An increase in the following was observed in the serum of patients with RCC compared with healthy controls: interleukin (IL)-4, IL-6, IL-8, IL-10, G-CSF, CXCL10, CXCL11, hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF). According to Ingenuity Pathway Analysis (IPA), CXCL10, IL-6, IL-8, epidermal growth factor (EGF), HGF and VEGF were associated with a network that controls cellular movement, tissue development and cellular growth. Kaplan-Meier analysis for disease-free survival showed that high numbers of CD4⁺/CD25(high+)/FOXP3⁺/CD45RA⁺ (Treg naïve) and low numbers of CD3⁻/CD16⁺/CD161⁺/CD158a⁺ (NK-Kir+) cells predict short disease-free survival in patients with RCC. CONCLUSION Concomitant evaluation of Treg (CD4⁺/CD25(high+)/FOXP3⁺ and CD4⁺/CD25(high+)/FOXP3⁺/CD45RA⁺) and of six soluble factors (IL-6, IL-8 ,VEGF, CXCL10, CXCL11, EGF, HGF) might be a surrogate marker of host immunity in patients with RCC.
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Affiliation(s)
- Marianeve Polimeno
- Oncological Immunology, National Cancer Institute 'G. Pascale', Mercogliano, Avellino
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Oleinika K, Nibbs RJ, Graham GJ, Fraser AR. Suppression, subversion and escape: the role of regulatory T cells in cancer progression. Clin Exp Immunol 2013. [PMID: 23199321 DOI: 10.1111/j.1365-2249.2012.04657.x] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Regulatory T cells (T(regs) ) are crucial in mediating immune homeostasis and promoting the establishment and maintenance of peripheral tolerance. However, in the context of cancer their role is more complex, and they are thought to contribute to the progress of many tumours. As cancer cells express both self- and tumour-associated antigens, T(regs) are key to dampening effector cell responses, and therefore represent one of the main obstacles to effective anti-tumour responses. Suppression mechanisms employed by T(regs) are thought to contribute significantly to the failure of current therapies that rely on induction or potentiation of anti-tumour responses. This review will focus on the current evidence supporting the central role of T(regs) in establishing tumour-specific tolerance and promoting cancer escape. We outline the mechanisms underlying their suppressive function and discuss the potential routes of T(regs) accumulation within the tumour, including enhanced recruitment, in-situ or local proliferation, and de-novo differentiation. In addition, we review some of the cancer treatment strategies that act, at least in part, to eliminate or interfere with the function of T(regs) . The role of T(regs) is being recognized increasingly in cancer, and controlling the function of these suppressive cells in the tumour microenvironment without compromising peripheral tolerance represents a significant challenge for cancer therapies.
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Affiliation(s)
- K Oleinika
- Chemokine Research Group, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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28
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Differential control of Helios(+/-) Treg development by monocyte subsets through disparate inflammatory cytokines. Blood 2013; 121:2494-502. [PMID: 23365462 DOI: 10.1182/blood-2012-11-469122] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Foxp3(+) regulatory T cells (Tregs) play a pivotal role in control of autoimmunity and pathological immune responses. Helios, the Ikarus family transcription factor, binds to the Foxp3 promoter, stabilizing its expression, and is expressed in 70% of peripheral Tregs of healthy individuals. This frequency is altered during malignancy, infection, and autoimmunity, although the mechanisms that control proliferation and relative numbers of Helios(+/-) Tregs remain largely unknown. Using a T-cell-monocyte in vitro stimulation assay, we now show that proliferation of Helios(+) Tregs is inhibited by CD16(+) monocyte subset. Antibody blocking with anti-interleukin (IL)-12 reversed this inhibition, whereas addition of IL-12 suppressed Helios(+) Treg expansion, indicating that CD16(+) monocyte control of Helios(+) Treg numbers is mediated through IL-12. In contrast, proliferation of Helios(-) Tregs, which express higher levels of tumor necrosis factor receptor II (TNFRII), was suppressed by TNF-α, whereas anti-TNF-α and anti-TNFRII reversed the inhibition. CD16(-) monocyte subset was mainly responsible for TNF-α-mediated control of Helios(-) Treg expansion. Altogether, these data suggest a differential role for monocyte subsets in control of Helios(+/-) Treg development that is mediated by distinct inflammatory cytokines. These data may have important implications for understanding the pathogenesis as well as control of chronic inflammatory and autoimmune diseases.
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Alexander T, Sattler A, Templin L, Kohler S, Groß C, Meisel A, Sawitzki B, Burmester GR, Arnold R, Radbruch A, Thiel A, Hiepe F. Foxp3+ Helios+ regulatory T cells are expanded in active systemic lupus erythematosus. Ann Rheum Dis 2012; 72:1549-58. [PMID: 23264341 DOI: 10.1136/annrheumdis-2012-202216] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Recent data debate the suitability of Helios, an Ikaros family member, as a marker for thymic-derived regulatory T cells (Treg). Nevertheless, Foxp3(+) Helios(+) Treg may be of particular relevance in mediating immune tolerance in chronic autoimmunity, such as systemic lupus erythematosus (SLE), as they possess enhanced suppressive function, compared to Foxp3(+) Helios(-) Treg. METHODS Multicolour flow cytometry was performed to analyse Foxp3 and Helios expression in peripheral blood CD4 T cells from SLE patients, compared to healthy controls (HC) and systemic sclerosis (SSc) and rheumatoid arthritis (RA) patients. Cytokine production, chemokine receptor expression for CXCR3 and CCR4, basal signal transducer and activator of transcription 5 (STAT5)a phosphorylation levels and T-cell receptor (TCR) Vβ repertoire were analysed by flow cytometry, and the methylation status of the Foxp3 locus (Treg-specific demethylated region, TSDR) by real-time PCR. RESULTS Frequencies of Foxp3(+) Helios(+) Treg, unlike Foxp3(+) Helios(-) T cells, were significantly increased in SLE patients and positively correlated with disease activity, whereas they were unaltered in SSc and RA patients. Compared to HC, Foxp3(+) Helios(+) Treg in SLE predominantly displayed a CD45RA(-)/CD31(-)/FoxP3(low) memory phenotype with increased Ki-67 expression, enhanced basal pSTAT5a levels and a restricted TCR repertoire. Nonetheless, similar to HC, Foxp3(+) Helios(+) Treg in SLE lacked effector cytokine production, possessed a highly demethylated TSDR and expressed comparable levels of CXCR3 and CCR4. CONCLUSIONS Our data suggest that Helios-expressing Foxp3(+) Treg with functional suppressive capacity and migratory potential into inflamed tissues are expanded in active SLE, presumably through γ-chain signalling cytokines and TCR stimulation, to compensate for autoreactive effector responses.
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Affiliation(s)
- Tobias Alexander
- Medical Department, Division of Rheumatology and Clinical Immunology, Charité-University Medicine, Berlin, Germany.
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Tanchot C, Terme M, Pere H, Tran T, Benhamouda N, Strioga M, Banissi C, Galluzzi L, Kroemer G, Tartour E. Tumor-infiltrating regulatory T cells: phenotype, role, mechanism of expansion in situ and clinical significance. CANCER MICROENVIRONMENT 2012; 6:147-57. [PMID: 23104434 DOI: 10.1007/s12307-012-0122-y] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 10/15/2012] [Indexed: 02/06/2023]
Abstract
In immunocompetent individuals, the immune system initially eradicates potentially tumorigenic cells as they develop, a capacity that is progressively lost when malignant cells acquire alterations that sustain immunosubversion and/or immunoevasion. One of the major mechanisms whereby cancer cells block antitumor immune responses involves a specific class of immunosuppressive T cells that-in the vast majority of cases-express the Forkhead box P3 (FOXP3) transcription factor. Such FOXP3(+) regulatory T cells (Tregs) accumulate within neoplastic lesions as a result of several distinct mechanisms, including increased infiltration, local expansion, survival advantage and in situ development from conventional CD4(+) cells. The prognostic/predictive significance of tumor infiltration by Tregs remains a matter of debate. Indeed, high levels of intratumoral Tregs have been associated with poor disease outcome in cohorts of patients affected by multiple, but not all, tumor types. This apparent discrepancy may relate to the existence of functionally distinct Treg subsets, to the fact that Tregs near-to-invariably infiltrate neoplastic lesions together with other cells from the immune system, notably CD4(+) and CD8(+) T lymphocytes and/or to peculiar features of some oncogenic programs that involve a prominent pro-inflammatory component. In this review, we will discuss the phenotype, function and clinical significance of various Treg subsets.
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Affiliation(s)
- C Tanchot
- INSERM U970, PARCC (Paris Cardiovascular Research Center), Paris, France,
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Abstract
INTRODUCTION Evidence suggests that FOXP3(+)CD25(high)CD4(+) regulatory T cells (Treg) which accumulate in cancer may have beneficial or unfavorable effects on prognosis. The presence in tumor-associated inflammatory infiltrates of two subsets of Treg with distinct phenotypic and functional profiles might explain these conflicting observations. AREAS COVERED Human inducible (i) Treg arising by tumor-driven conversion of conventional CD4(+) T cells are highly suppressive, therapy-resistant Treg which down-regulate anti-tumor immune responses, promoting tumor growth. Natural (n) Treg, normally responsible for maintaining peripheral tolerance, control cancer-associated inflammation, which favors tumor progression. This division of labor between nTreg and iTreg is not absolute, and overlap may be common. Nevertheless, iTreg play a critical and major role in cancer and cancer therapy. The tumor microenvironment determines the type, frequency and suppression levels of accumulating Treg. EXPERT OPINION In cancer, a selective removal or silencing of iTreg and not of nTreg should be a therapeutic goal. However, the implementation of this challenging strategy requires further studies of cellular and molecular crosstalk among immune cells in the tumor microenvironment.
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Affiliation(s)
- Theresa L Whiteside
- University of Pittsburgh Cancer Institute, Pathology, Hillman Cancer Center, 5117 Centre Ave, Pittsburgh, PA 15213, USA.
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Elkord E. Comment on "Expression of Helios in peripherally induced Foxp3+ regulatory T cells". THE JOURNAL OF IMMUNOLOGY 2012; 189:500; author reply 500-1. [PMID: 22773660 DOI: 10.4049/jimmunol.1290033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Whiteside TL. What are regulatory T cells (Treg) regulating in cancer and why? Semin Cancer Biol 2012; 22:327-34. [PMID: 22465232 DOI: 10.1016/j.semcancer.2012.03.004] [Citation(s) in RCA: 195] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 03/15/2012] [Indexed: 02/06/2023]
Abstract
The role regulatory T cells (Treg) play in cancer development and progression is not clear. Earlier evidence suggested that CD4(+)FOXP3(+)CD25(high) Treg accumulate in tumors and the peripheral blood of patients with cancer and through suppression of anti-tumor immune responses promote tumor growth. However, more recent data indicate that in certain cancers, such as colorectal carcinoma (CRC), Treg suppress bacteria-driven inflammation which promotes carcinogenesis and thus benefit the host. Treg appear to play a dual role in cancer. This might explain why the frequency and functions of Treg are associated with a poor prognosis in some cancers but with favorable outcome in others. The clinical and prognostic significance of Treg in cancer depends on environmental factors, including infectious agents, tumor-derived products and locally-produced cytokines, which shape the nature of immune responses, including Treg generation, recruitment and survival. Adaptive or inducible (i) Treg or Tr1 are the major subset(s) of Treg present in cancer. These iTreg are a distinct subset of regulatory cells that phenotypically and functionally differ from FOXP3(+) natural (n) Treg responsible for peripheral tolerance. They mediate powerful suppression of effector T cells via diverse mechanisms, produce immunosuppressive cytokines, notably TGF-β as well as prostaglandin E2 and adenosine, and are resistant to apoptosis or oncological therapies. Strategies for silencing of Tr1 in patients with cancer will require novel approaches that can selectively deplete these cells or block molecular pathways they utilize.
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Affiliation(s)
- Theresa L Whiteside
- University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA 15213, USA.
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Wang C, Lee JH, Kim CH. Optimal population of FoxP3+ T cells in tumors requires an antigen priming-dependent trafficking receptor switch. PLoS One 2012; 7:e30793. [PMID: 22292042 PMCID: PMC3264621 DOI: 10.1371/journal.pone.0030793] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 12/29/2011] [Indexed: 01/21/2023] Open
Abstract
FoxP3+ T cells populate tumors and regulate anti-tumor immunity. The requirement for optimal population of FoxP3+ regulatory T cells in tumors remains unclear. We investigated the migration requirement and stability of tumor-associated FoxP3+ T cells. We found that only memory, but not naïve, FoxP3+ T cells are highly enriched in tumors. Almost all of the tumor-infiltrating FoxP3+ T cells express Helios, an antigen associated either with thymus-generated FoxP3+ T cells or activated T cells in the periphery. The tumor-infiltrating FoxP3+ T cells largely lack CD62L and CCR7, two trafficking receptors required for T cell migration into secondary lymphoid tissues. Instead, the tumor infiltrating FoxP3+ T cells highly express memory/tumor-associated CCR8 and CXCR4. Antigen priming is required for induction of this trafficking receptor phenotype in FoxP3+ T cells and only antigen primed, but not antigen-inexperienced naive, FoxP3+ T cells can efficiently migrate into tumors. While the migration of FoxP3+ T cells into tumors was a readily detectable event, generation of induced FoxP3+ T cells within tumors was unexpectedly inefficient. Genetic marking of current and ex-FoxP3+ T cells revealed that tumor-infiltrating FoxP3+ T cells are highly stable and do not readily convert back to FoxP3− T cells. Taken together, our results indicate that population of tumors with thymus-generated FoxP3+ T cells requires an antigen priming-dependent trafficking receptor switch in lymphoid tissues.
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Affiliation(s)
- Chuanwu Wang
- Laboratory of Immunology and Hematopoiesis, Department of Comparative Pathobiology, Purdue Cancer Center, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Jee H. Lee
- Laboratory of Immunology and Hematopoiesis, Department of Comparative Pathobiology, Purdue Cancer Center, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Chang H. Kim
- Laboratory of Immunology and Hematopoiesis, Department of Comparative Pathobiology, Purdue Cancer Center, Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
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Abstract
Regulatory T lymphocytes are essential to maintain homeostasis of the immune system, limiting the magnitude of effector responses and allowing the establishment of immunological tolerance. Two main types of regulatory T cells have been identified--natural and induced (or adaptive)-and both play significant roles in tuning down effector immune responses. Adaptive CD4(+)Foxp3(+) regulatory T (iTreg) cells develop outside the thymus under a variety of conditions. These include not only antigen presentation under subimmunogenic or noninflammatory conditions, but also chronic inflammation and infections. We speculate that the different origin of iTreg cells (noninflammatory versus inflammatory) results in distinct properties, including their stability. iTreg cells are also generated during homeostasis of the gut and in cancer, although some cancers also favor expansion of natural regulatory T (nTreg) cells. Here we review how iTreg cells develop and how they participate in immunological tolerance, contrasting, when possible, iTreg cells with nTreg cells.
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Affiliation(s)
- Angelina M Bilate
- Molecular Pathogenesis Program, Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA.
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Tenorio EP, Fernández J, Castellanos C, Olguín JE, Saavedra R. CD4+Foxp3+ regulatory T cells mediate Toxoplasma gondii-induced T-cell suppression through an IL-2-related mechanism but independently of IL-10. Eur J Immunol 2011; 41:3529-41. [DOI: 10.1002/eji.201141507] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 08/04/2011] [Accepted: 09/06/2011] [Indexed: 11/09/2022]
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