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Borelli A, Santamaria JC, Zamit C, Apert C, Chevallier J, Pierre P, Argüello RJ, Spinelli L, Irla M. Lymphotoxin limits Foxp3 + regulatory T cell development from Foxp3 lo precursors via IL-4 signaling. Nat Commun 2024; 15:6976. [PMID: 39143070 PMCID: PMC11324892 DOI: 10.1038/s41467-024-51164-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 07/31/2024] [Indexed: 08/16/2024] Open
Abstract
Regulatory T cells (Treg) are critical players of immune tolerance that develop in the thymus via two distinct developmental pathways involving CD25+Foxp3- and CD25-Foxp3lo precursors. However, the mechanisms regulating the recently identified Foxp3lo precursor pathway remain unclear. Here, we find that the membrane-bound lymphotoxin α1β2 (LTα1β2) heterocomplex is upregulated during Treg development upon TCR/CD28 and IL-2 stimulation. We show that Lta expression limits the maturational development of Treg from Foxp3lo precursors by regulating their proliferation, survival, and metabolic profile. Transgenic reporter mice and transcriptomic analyses further reveal that medullary thymic epithelial cells (mTEC) constitute an unexpected source of IL-4. We demonstrate that LTα1β2-lymphotoxin β receptor-mediated interactions with mTEC limit Treg development by down-regulating IL-4 expression in mTEC. Collectively, our findings identify the lymphotoxin axis as the first inhibitory checkpoint of thymic Treg development that fine-tunes the Foxp3lo Treg precursor pathway by limiting IL-4 availability.
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Affiliation(s)
- Alexia Borelli
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Jérémy C Santamaria
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Cloé Zamit
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Cécile Apert
- Toulouse Institute for Infectious and Inflammatory Diseases (Infinity), INSERM UMR1291-CNRS UMR5051-University Toulouse III, Toulouse, France
- Microenvironment & Immunity Unit, Institut Pasteur, Paris, France
| | - Jessica Chevallier
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Philippe Pierre
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Rafael J Argüello
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Lionel Spinelli
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France
| | - Magali Irla
- Aix-Marseille University, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Turing Centre for Living Systems, Marseille, France.
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2
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Chetty-Sebastian D, Assounga AG. Regulatory T cell frequency in peripheral blood of women with advanced cervical Cancer including women living with HIV. BMC Cancer 2023; 23:830. [PMID: 37670247 PMCID: PMC10481519 DOI: 10.1186/s12885-023-11345-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 08/28/2023] [Indexed: 09/07/2023] Open
Abstract
BACKGROUND Persistent high-risk Human papillomavirus (HR-HPV) infections are the main cause of cervical cancer. Cumulative evidence implicates regulatory T cells (Tregs) as a critical factor in the failure to eliminate HPV-induced cancers leading to their persistence and progression to cancer. Also, the WHO recognised cervical cancer as 100% attributable to persistent HR-HPV infection. The province of KwaZulu-Natal (KZN) in South Africa has a high prevalence of cervical cancer and HIV infection. MATERIALS AND METHODS We evaluated Treg frequency in dual infection of HR HPV and HIV coinfection using phenotypic markers, CD4, CD25 and intracellular Foxp3, in the peripheral blood of 51 cervical cancer and 46 non-cervical cancer participants and evaluated the effect of HIV on regulatory T cell proportion. Peripheral blood mononuclear cells were surface stained with a cocktail fluorescent labelled CD4 and CD25 and subsequently with APC anti-human FoxP3 (eBioscience). Flow cytometry was performed with FACS analysis. Statistical analysis of results was done using Instat 3 program (GraphpadR). Tregs results were expressed as median ± interquartile range (IQR). Associations of cervical cancer with demographic, clinical and laboratory variables were evaluated by univariate and multivariate logistic regression analysis using SPSS version 27 (IBM). RESULTS Tregs frequency was significantly higher in individuals with cervical cancer (11.00 ± 19.79%) compared to controls (1.71 ± 8.91%) (p < 0.0001). HIV infection was associated with an increase in Tregs frequency. In controls a significant difference in Tregs frequency was noted between women living with HIV (6.00 ± 10.57%, n = 9) and those without HIV (1.30 ± 6.10%, n = 37), p = 0.0023. In multivariate logistic regression, Tregs frequency was significantly associated with cervical cancer after controlling for age, smoking, weight loss, presence of STI, HIV and HPV genotype. DISCUSSION/CONCLUSION Higher Tregs frequency was significantly associated with cervical cancer highlighting the immunosuppressive role of Tregs in cervical cancer. Treg frequency was more strongly associated with cervical cancer than HIV infection. We provide baseline data for monitoring Treg frequencies in response to new preventive and therapeutic strategies in the management of cervical cancer.
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Affiliation(s)
- Devamani Chetty-Sebastian
- Clinical Medicine laboratory, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4001 South Africa
| | - Alain G. Assounga
- Clinical Medicine laboratory, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4001 South Africa
- Dept of Nephrology, Div. of Internal Medicine, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4001 South Africa
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3
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Wang C, Kong L, Kim S, Lee S, Oh S, Jo S, Jang I, Kim TD. The Role of IL-7 and IL-7R in Cancer Pathophysiology and Immunotherapy. Int J Mol Sci 2022; 23:ijms231810412. [PMID: 36142322 PMCID: PMC9499417 DOI: 10.3390/ijms231810412] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/06/2022] [Accepted: 09/06/2022] [Indexed: 12/03/2022] Open
Abstract
Interleukin-7 (IL-7) is a multipotent cytokine that maintains the homeostasis of the immune system. IL-7 plays a vital role in T-cell development, proliferation, and differentiation, as well as in B cell maturation through the activation of the IL-7 receptor (IL-7R). IL-7 is closely associated with tumor development and has been used in cancer clinical research and therapy. In this review, we first summarize the roles of IL-7 and IL-7Rα and their downstream signaling pathways in immunity and cancer. Furthermore, we summarize and discuss the recent advances in the use of IL-7 and IL-7Rα as cancer immunotherapy tools and highlight their potential for therapeutic applications. This review will help in the development of cancer immunotherapy regimens based on IL-7 and IL-7Rα, and will also advance their exploitation as more effective and safe immunotherapy tools.
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Affiliation(s)
- Chunli Wang
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
| | - Lingzu Kong
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon 34134, Korea
| | - Seokmin Kim
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Sunyoung Lee
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Sechan Oh
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Seona Jo
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Inhwan Jang
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Tae-Don Kim
- Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon 34113, Korea
- Correspondence:
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4
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Shive C, Pandiyan P. Inflammation, Immune Senescence, and Dysregulated Immune Regulation in the Elderly. FRONTIERS IN AGING 2022; 3:840827. [PMID: 35821823 PMCID: PMC9261323 DOI: 10.3389/fragi.2022.840827] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/30/2022] [Indexed: 12/22/2022]
Abstract
An optimal immune response requires the appropriate interaction between the innate and the adaptive arms of the immune system as well as a proper balance of activation and regulation. After decades of life, the aging immune system is continuously exposed to immune stressors and inflammatory assaults that lead to immune senescence. In this review, we will discuss inflammaging in the elderly, specifically concentrating on IL-6 and IL-1b in the context of T lymphocytes, and how inflammation is related to mortality and morbidities, specifically cardiovascular disease and cancer. Although a number of studies suggests that the anti-inflammatory cytokine TGF-b is elevated in the elderly, heightened inflammation persists. Thus, the regulation of the immune response and the ability to return the immune system to homeostasis is also important. Therefore, we will discuss cellular alterations in aging, concentrating on senescent T cells and CD4+ CD25+ FOXP3+ regulatory T cells (Tregs) in aging
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Affiliation(s)
- Carey Shive
- Louis Stokes Cleveland VA Medical Center, United States Department of Veterans Affairs, Cleveland, OH, United States.,Case Western Reserve University, Cleveland, OH, United States
| | - Pushpa Pandiyan
- Case Western Reserve University, Cleveland, OH, United States
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Harjacek M. Immunopathophysiology of Juvenile Spondyloarthritis (jSpA): The "Out of the Box" View on Epigenetics, Neuroendocrine Pathways and Role of the Macrophage Migration Inhibitory Factor (MIF). Front Med (Lausanne) 2021; 8:700982. [PMID: 34692718 PMCID: PMC8526544 DOI: 10.3389/fmed.2021.700982] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 09/06/2021] [Indexed: 12/11/2022] Open
Abstract
Juvenile spondyloarthritis (jSpA) is a an umbrella term for heterogeneous group of related seronegative inflammatory disorders sharing common symptoms. Although it mainly affects children and adolescents, it often remains active during adulthood. Genetic and environmental factors are involved in its occurrence, although the exact underlying immunopathophysiology remains incompletely elucidated. Accumulated evidence suggests that, in affected patients, subclinical gut inflammation caused by intestinal dysbiosis, is pivotal to the future development of synovial-entheseal complex inflammation. While the predominant role of IL17/23 axis, TNF-α, and IL-7 in the pathophysiology of SpA, including jSpA, is firmly established, the role of the cytokine macrophage migration inhibitory factor (MIF) is generally overlooked. The purpose of this review is to discuss and emphasize the role of epigenetics, neuroendocrine pathways and the hypothalamic-pituitary (HPA) axis, and to propose a novel hypothesis of the role of decreased NLRP3 gene expression and possibly MIF in the early phases of jSpA development. The decreased NLRP3 gene expression in the latter, due to hypomethylation of promotor site, is (one of) the cause for inflammasome malfunction leading to gut dysbiosis observed in patients with early jSpA. In addition, we highlight the role of MIF in the complex innate, adaptive cellular and main effector cytokine network, Finally, since treatment of advanced bone pathology in SpA remains an unmet clinical need, I suggest possible new drug targets with the aim to ultimately improve treatment efficacy and long-term outcome of jSpA patients.
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Affiliation(s)
- Miroslav Harjacek
- Department of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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6
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Pandiyan P, McCormick TS. Regulation of IL-17A-Producing Cells in Skin Inflammatory Disorders. J Invest Dermatol 2021; 142:867-875. [PMID: 34561088 DOI: 10.1016/j.jid.2021.06.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 06/09/2021] [Accepted: 06/22/2021] [Indexed: 12/11/2022]
Abstract
This review focuses on the IL-17A family of cytokines produced by T lymphocytes and other immune cells and how they are involved in cutaneous pathogenic responses. It will also discuss cutaneous dysbiosis and FOXP3+ regulatory T cells in the context of inflammatory conditions linked to IL-17 responses in the skin. Specifically, it will review key literature on chronic mucocutaneous candidiasis and psoriasis.
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Affiliation(s)
- Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA; Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
| | - Thomas S McCormick
- Department of Dermatology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
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7
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Bhaskaran N, Jayaraman S, Quigley C, Mamileti P, Ghannoum M, Weinberg A, Thuener J, Pan Q, Pandiyan P. The Role of Dectin-1 Signaling in Altering Tumor Immune Microenvironment in the Context of Aging. Front Oncol 2021; 11:669066. [PMID: 33968777 PMCID: PMC8100664 DOI: 10.3389/fonc.2021.669066] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/06/2021] [Indexed: 01/10/2023] Open
Abstract
An increased accumulation of immune-dysfunction-associated CD4+Foxp3+ regulatory T cells (Tregs) is observed in aging oral mucosa during infection. Here we studied the function of Tregs during oral cancer development in aging mucosa. First, we found heightened proportions of Tregs and myeloid-derived suppressor cells (MDSC) accumulating in mouse and human oral squamous cell carcinoma (OSCC) tissues. Using the mouse 4-Nitroquinoline 1-oxide(4-NQO) oral carcinogenesis model, we found that tongues of aged mice displayed increased propensity for epithelial cell dysplasia, hyperplasia, and accelerated OSCC development, which coincided with significantly increased abundance of IL-1β, Tregs, and MDSC in tongues. Partial depletion of Tregs reduced tumor burden. Moreover, fungal abundance and dectin-1 signaling were elevated in aged mice suggesting a potential role for dectin-1 in modulating immune environment and tumor development. Confirming this tenet, dectin-1 deficient mice showed diminished IL-1β, reduced infiltration of Tregs and MDSC in the tongues, as well as slower progression and reduced severity of tumor burden. Taken together, these data identify an important role of dectin-1 signaling in establishing the intra-tumoral immunosuppressive milieu and promoting OSCC tumorigenesis in the context of aging.
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Affiliation(s)
- Natarajan Bhaskaran
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Sangeetha Jayaraman
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Cheriese Quigley
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Prerna Mamileti
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Mahmoud Ghannoum
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Dermatology, School of Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Aaron Weinberg
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Case Comprehensive Cancer Center, Case Western Reserve University, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Jason Thuener
- Otolaryngology-Head and Neck surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Quintin Pan
- Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Otolaryngology-Head and Neck surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| | - Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Department of Pathology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Case Comprehensive Cancer Center, Case Western Reserve University, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
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8
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Chu KH, Lin SY, Chiang BL. STAT6 Pathway Is Critical for the Induction and Function of Regulatory T Cells Induced by Mucosal B Cells. Front Immunol 2021; 11:615868. [PMID: 33584704 PMCID: PMC7878545 DOI: 10.3389/fimmu.2020.615868] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022] Open
Abstract
B cells could convert naïve T cells into regulatory T cells (so-called Treg-of-B cells) which have the ability to treat animal models of inflammatory diseases, including allergic asthma, collagen-induced arthritis and colitis; however, the mechanisms of Treg-of-B cell generation remain unclear. In this study, we investigated the role of STAT6 in the generation of Treg-of-B (P) cells, which Treg cells were generated by Peyer’s patch B cells (P stands for Peyer’s patch). CD4+CD25- T cells from wild type, STAT6 knockout and IL-4 knockout mice were cocultured with wild type Peyer’s patch B cells for Treg-of-B (P) cell generation. A murine asthmatic model was used to analyze the in vivo regulatory function of Treg-of-B (P) cells. The data demonstrated that STAT6 played a critical role in the generation of Treg-of-B (P) cells, which confirmed with STAT6-deficient T cells and the STAT6 inhibitor AS1517499. When STAT6 was lacking, Treg-of-B (P) cells exerted impaired suppressive ability with decreased LAG3 expression. Furthermore, Peyer’s patch B cells played an essential role in regulatory T cell generation. In the absence of Peyer’s patch B cells, T cells expressed decreased phosphorylated STAT6, which was followed by decreased LAG3 expression and impaired suppressive ability, suggesting that Peyer’s patch B cells provided the critical signal to activate STAT6 phosphorylation in T cells. Moreover, STAT6 deficient Treg-of-B (P) cells could not alleviate inflammation in an animal model of asthma in vivo. IL-4 was downstream of phosphorylated STAT6 and maintained Treg-of-B (P) cell survival with increased expression of Bcl-2 and BclXL. We reported a novel finding that the STAT6-LAG3 signaling axis is important for the induction and function of Treg-of-B (P) cells.
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Affiliation(s)
- Kuan-Hua Chu
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Szu-Yu Lin
- Graduate Institute of Immunology, National Taiwan University, Taipei, Taiwan
| | - Bor-Luen Chiang
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan.,Graduate Institute of Immunology, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan.,Allergy Center, National Taiwan University Hospital, Taipei, Taiwan
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9
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Weinberg A, Tugizov S, Pandiyan P, Jin G, Rakshit S, Vyakarnam A, Naglik JR. Innate immune mechanisms to oral pathogens in oral mucosa of HIV-infected individuals. Oral Dis 2020; 26 Suppl 1:69-79. [PMID: 32862519 PMCID: PMC7570967 DOI: 10.1111/odi.13470] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A crucial aspect of mucosal HIV transmission is the interaction between HIV, the local environmental milieu and immune cells. The oral mucosa comprises many host cell types including epithelial cells, CD4 + T cells, dendritic cells and monocytes/macrophages, as well as a diverse microbiome predominantly comprising bacterial species. While the oral epithelium is one of the first sites exposed to HIV through oral-genital contact and nursing infants, it is largely thought to be resistant to HIV transmission via mechanisms that are still unclear. HIV-1 infection is also associated with predisposition to secondary infections, such as tuberculosis, and other diseases including cancer. This review addresses the following questions that were discussed at the 8th World Workshop on Oral Health and Disease in AIDS held in Bali, Indonesia, 13 September –15 September 2019: (a) How does HIV infection affect epithelial cell signalling? (b) How does HIV infection affect the production of cytokines and other innate antimicrobial factors, (c) How is the mucosal distribution and function of immune cells altered in HIV infection? (d) How do T cells affect HIV (oral) pathogenesis and cancer? (e) How does HIV infection lead to susceptibility to TB infections?
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Affiliation(s)
- Aaron Weinberg
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Sharof Tugizov
- Department of Medicine, University of California-San Francisco, San Francisco, CA, USA
| | - Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Ge Jin
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Srabanti Rakshit
- Peter Gorer Department of Immunobiology, School of Immunology and Microbial Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Annapurna Vyakarnam
- Peter Gorer Department of Immunobiology, School of Immunology and Microbial Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK.,Laboratory of Immunology of HIV-TB co-infection, Centre for Infectious Disease Research, Indian Institute of Science, Bangalore, India
| | - Julian R Naglik
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, UK
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10
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Hossain MA, Liu G, Dai B, Si Y, Yang Q, Wazir J, Birnbaumer L, Yang Y. Reinvigorating exhausted CD8 + cytotoxic T lymphocytes in the tumor microenvironment and current strategies in cancer immunotherapy. Med Res Rev 2020; 41:156-201. [PMID: 32844499 DOI: 10.1002/med.21727] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 06/26/2020] [Accepted: 08/11/2020] [Indexed: 02/06/2023]
Abstract
Immunotherapy has revolutionized the treatment of cancer in recent years and achieved overall success and long-term clinical benefit in patients with a wide variety of cancer types. However, there is still a large proportion of patients exhibiting limited or no responses to immunotherapeutic strategy, some of which were even observed with hyperprogressive disease. One major obstacle restricting the efficacy is that tumor-reactive CD8+ T cells, which are central for tumor control, undergo exhaustion, and lose their ability to eliminate cancer cells after infiltrating into the strongly immunosuppressive tumor microenvironment. Thus, as a potential therapeutic rationale in the development of cancer immunotherapy, targeting or reinvigorating exhausted CD8+ T cells has been attracting much interest. Hitherto, both intrinsic and extrinsic mechanisms that govern CD8+ T-cell exhaustion have been explored. Specifically, the transcriptional and epigenetic landscapes have been depicted utilizing single-cell RNA sequencing or mass cytometry (CyTOF). In addition, cellular metabolism dictating the tumor-infiltrating CD8+ T-cell fate is currently under investigation. A series of clinical trials are being carried out to further establish the current strategies targeting CD8+ T-cell exhaustion. Taken together, despite the proven benefit of immunotherapy in cancer patients, additional efforts are still needed to fully circumvent limitations of exhausted T cells in the treatment. In this review, we will focus on the current cellular and molecular understanding of metabolic changes, epigenetic remodeling, and transcriptional regulation in CD8+ T-cell exhaustion and describe hypothetical treatment approaches based on immunotherapy aiming at reinvigorating exhausted CD8+ T cells.
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Affiliation(s)
- Md Amir Hossain
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Guilai Liu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Beiying Dai
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Yaxuan Si
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Qitao Yang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Junaid Wazir
- Department of Clinical Pharmacy, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, Durham, North Carolina, USA.,Institute of Biomedical Research (BIOMED), Catholic University of Argentina, Buenos Aires, Argentina
| | - Yong Yang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China.,Department of Clinical Pharmacy, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China
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11
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Verma A, Mathur R, Farooque A, Kaul V, Gupta S, Dwarakanath BS. T-Regulatory Cells In Tumor Progression And Therapy. Cancer Manag Res 2019; 11:10731-10747. [PMID: 31920383 PMCID: PMC6935360 DOI: 10.2147/cmar.s228887] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/06/2019] [Indexed: 12/24/2022] Open
Abstract
Regulatory T cells (Tregs) are important members of the immune system regulating the host responses to infection and neoplasms. Tregs prevent autoimmune disorders by protecting the host-cells from an immune response, related to the peripheral tolerance. However, tumor cells use Tregs as a shield to protect themselves against anti-tumor immune response. Thus, Tregs are a hurdle in achieving the complete potential of anti-cancer therapies including immunotherapy. This has prompted the development of novel adjuvant therapies that obviate their negative effects thereby enhancing the therapeutic efficacy. Our earlier studies have shown the efficacy of the glycolytic inhibitor, 2-deoxy-D-glucose (2-DG) by reducing the induced Tregs pool and enhance immune stimulation as well as local tumor control. These findings have suggested its potential for enhancing the efficacy of immunotherapy, besides radiotherapy and chemotherapy. This review provides a brief account of the current status of Tregs as a component of the immune-biology of tumors and various preclinical and clinical strategies pursued to obviate the limitations imposed by them in achieving therapeutic efficacy.
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Affiliation(s)
- Amit Verma
- Armed Forces Radiobiology Research Institute, Uniformed Services University, Bethesda, MD, USA
| | - Rohit Mathur
- Department of Lymphoma and Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Vandana Kaul
- Division of Abdominal Transplantation, Department of Surgery, Stanford University, Stanford, CA, USA
| | - Seema Gupta
- Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
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12
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Zheng L, Li J, Lenardo M. Restimulation-induced cell death: new medical and research perspectives. Immunol Rev 2018; 277:44-60. [PMID: 28462523 DOI: 10.1111/imr.12535] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In the periphery, homeostasis of the immune system depends on the equilibrium of expanding and contracting T lymphocytes during immune response. An important mechanism of lymphocyte contraction is clonal depletion of activated T cells by cytokine withdrawal induced death (CWID) and TCR restimulation induced cell death (RICD). Deficiencies in signaling components for CWID and RICD leads to autoimmunune lymphoproliferative disorders in mouse and human. The most important feature of CWID and RICD is clonal specificity, which lends great appeal as a strategy for targeted tolerance induction and treatment of autoimmune diseases, allergic disorders, and graft rejection by depleting undesired disease-causing T cells while keeping the overall host immunity intact.
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Affiliation(s)
- Lixin Zheng
- Laboratory of Immunology and Clinical Genomics Program, Molecular Development of the Immune System Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jian Li
- Laboratory of Immunology and Clinical Genomics Program, Molecular Development of the Immune System Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.,Institute of Immunology, Third Military Medical University, Chongqing, China
| | - Michael Lenardo
- Laboratory of Immunology and Clinical Genomics Program, Molecular Development of the Immune System Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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13
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Yang WC, Hwang YS, Chen YY, Liu CL, Shen CN, Hong WH, Lo SM, Shen CR. Interleukin-4 Supports the Suppressive Immune Responses Elicited by Regulatory T Cells. Front Immunol 2017; 8:1508. [PMID: 29184551 PMCID: PMC5694475 DOI: 10.3389/fimmu.2017.01508] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/25/2017] [Indexed: 11/13/2022] Open
Abstract
Interleukin-4 (IL-4) has been considered as one of the tolerogenic cytokines in many autoimmune animal models and clinical settings. Despite its role in antagonizing pathogenic Th1 responses, little is known about whether IL-4 possesses functions that affect regulatory T cells (Tregs). Tregs are specialized cells responsible for the maintenance of peripheral tolerance through their immune modulatory capabilities. Interestingly, it has been suggested that IL-4 supplement at a high concentration protects responder T cells (Tresps) from Treg-mediated immune suppression. In addition, such supplement also impedes TGF-β-induced Treg differentiation in vitro. However, these phenomena may contradict the tolerogenic role of IL-4, and the effects of IL-4 on Tregs are therefore needed to be further elucidated. In this study, we utilized IL-4 knockout (KO) mice to validate the role of IL-4 on Treg-mediated immune suppression. Although IL-4 KO and control animals harbor similar frequencies of Tregs, Tregs from IL-4 KO mice weakly suppressed autologous Tresp activation. In addition, IL-4 deprivation impaired the ability of Tregs to modulate immune response, whereas IL-4 supplementation reinforced IL-4 KO Tregs in their function in suppressing Tresps. Finally, the presence of IL-4 was associated with increased cell survival and granzyme expression of Tregs. These results suggest the essential role of IL-4 in supporting Treg-mediated immune suppression, which may benefit the development of therapeutic strategies for autoimmune diseases.
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Affiliation(s)
- Wei-Cheng Yang
- Department and Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan
| | - Yih-Shiou Hwang
- Department of Medicine, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Department of Ophthalmology, Lin-Kou Chang Gung Memorial Hospital, Taoyuan City, Taiwan
| | - Ying-Yu Chen
- Department and Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City, Taiwan
| | - Chao-Lin Liu
- Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City, Taiwan.,College of Engineering, Chang Gung University, Taoyuan City, Taiwan
| | - Chia-Ning Shen
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Wei-Hsin Hong
- Department and Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City, Taiwan
| | - Sheng-Min Lo
- Department and Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan
| | - Chia-Rui Shen
- Department and Graduate Institute of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.,Department of Ophthalmology, Lin-Kou Chang Gung Memorial Hospital, Taoyuan City, Taiwan
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14
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Janssen E, Kumari S, Tohme M, Ullas S, Barrera V, Tas JM, Castillo-Rama M, Bronson RT, Usmani SM, Irvine DJ, Mempel TR, Geha RS. DOCK8 enforces immunological tolerance by promoting IL-2 signaling and immune synapse formation in Tregs. JCI Insight 2017; 2:94298. [PMID: 28978806 DOI: 10.1172/jci.insight.94298] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/29/2017] [Indexed: 12/29/2022] Open
Abstract
Patients deficient in the guanine nucleotide exchange factor DOCK8 have decreased numbers and impaired in vitro function of Tregs and make autoantibodies, but they seldom develop autoimmunity. We show that, similarly, Dock8-/- mice have decreased numbers and impaired in vitro function of Tregs but do not develop autoimmunity. In contrast, mice with selective DOCK8 deficiency in Tregs develop lymphoproliferation, autoantibodies, and gastrointestinal inflammation, despite a normal percentage and in vitro function of Tregs, suggesting that deficient T effector cell function might protect DOCK8-deficient patients from autoimmunity. We demonstrate that DOCK8 associates with STAT5 and is important for IL-2-driven STAT5 phosphorylation in Tregs. DOCK8 localizes within the lamellar actin ring of the Treg immune synapse (IS). Dock8-/- Tregs have abnormal TCR-driven actin dynamics, decreased adhesiveness, an altered gene expression profile, an unstable IS with decreased recruitment of signaling molecules, and impaired transendocytosis of the costimulatory molecule CD86. These data suggest that DOCK8 enforces immunological tolerance by promoting IL-2 signaling, TCR-driven actin dynamics, and the IS in Tregs.
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Affiliation(s)
- Erin Janssen
- Division of Immunology, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Sudha Kumari
- Department of Bioengineering and Koch Institute of Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Mira Tohme
- Division of Immunology, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Sumana Ullas
- Division of Immunology, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Victor Barrera
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Jeroen Mj Tas
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Marcela Castillo-Rama
- Division of Immunology, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Roderick T Bronson
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Shariq M Usmani
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Darrell J Irvine
- Department of Bioengineering and Koch Institute of Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Thorsten R Mempel
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Raif S Geha
- Division of Immunology, Boston Children's Hospital, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
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15
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Bhaskaran N, Quigley C, Weinberg A, Huang A, Popkin D, Pandiyan P. Transforming growth factor-β1 sustains the survival of Foxp3(+) regulatory cells during late phase of oropharyngeal candidiasis infection. Mucosal Immunol 2016; 9:1015-26. [PMID: 26530137 PMCID: PMC4854793 DOI: 10.1038/mi.2015.115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 09/21/2015] [Indexed: 02/04/2023]
Abstract
As CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) play crucial immunomodulatory roles during infections, one key question is how these cells are controlled during antimicrobial immune responses. Mechanisms controlling their homeostasis are central to ensure efficient protection against pathogens, as well as to control infection-associated immunopathology. Here we studied how their viability is regulated in the context of mouse oropharyngeal candidiasis (OPC) infection, and found that these cells show increased protection from apoptosis during late phase of infection and reinfection. Tregs underwent reduced cell death because they are refractory to T cell receptor restimulation-induced cell death (RICD). We confirmed their resistance to RICD, using mouse and human Tregs in vitro, and by inducing α-CD3 antibody-mediated apoptosis in vivo. The enhanced viability is dependent on increased transforming growth factor-β1 (TGF-β1) signaling that results in upregulation of cFLIP (cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein) in Tregs. Protection from cell death is abrogated in the absence of TGF-β1 signaling in Tregs during OPC infection. Taken together, our data unravel the previously unrecognized role of TGF-β1 in promoting Treg viability, coinciding with the pronounced immunomodulatory role of these cells during later phase of OPC infection, and possibly other mucosal infections.
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Affiliation(s)
- N Bhaskaran
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - C Quigley
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - A Weinberg
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - A Huang
- Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - D Popkin
- Department of Dermatology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - P Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA
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16
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Pandiyan P, Younes SA, Ribeiro SP, Talla A, McDonald D, Bhaskaran N, Levine AD, Weinberg A, Sekaly RP. Mucosal Regulatory T Cells and T Helper 17 Cells in HIV-Associated Immune Activation. Front Immunol 2016; 7:228. [PMID: 27379092 PMCID: PMC4913236 DOI: 10.3389/fimmu.2016.00228] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/26/2016] [Indexed: 12/12/2022] Open
Abstract
Residual mucosal inflammation along with chronic systemic immune activation is an important feature in individuals infected with human immunodeficiency virus (HIV), and has been linked to a wide range of co-morbidities, including malignancy, opportunistic infections, immunopathology, and cardiovascular complications. Although combined antiretroviral therapy (cART) can reduce plasma viral loads to undetectable levels, reservoirs of virus persist, and increased mortality is associated with immune dysbiosis in mucosal lymphoid tissues. Immune-based therapies are pursued with the goal of improving CD4+ T-cell restoration, as well as reducing chronic immune activation in cART-treated patients. However, the majority of research on immune activation has been derived from analysis of circulating T cells. How immune cell alterations in mucosal tissues contribute to HIV immune dysregulation and the associated risk of non-infectious chronic complications is less studied. Given the significant differences between mucosal T cells and circulating T cells, and the immediate interactions of mucosal T cells with the microbiome, more attention should be devoted to mucosal immune cells and their contribution to systemic immune activation in HIV-infected individuals. Here, we will focus on mucosal immune cells with a specific emphasis on CD4+ T lymphocytes, such as T helper 17 cells and CD4+Foxp3+ regulatory T cells (Tregs), which play crucial roles in maintaining mucosal barrier integrity and preventing inflammation, respectively. We hypothesize that pro-inflammatory milieu in cART-treated patients with immune activation significantly contributes to enhanced loss of Th17 cells and increased frequency of dysregulated Tregs in the mucosa, which in turn may exacerbate immune dysfunction in HIV-infected patients. We also present initial evidence to support this hypothesis. A better comprehension of how pro-inflammatory milieu impacts these two types of cells in the mucosa will shed light on mucosal immune dysfunction and HIV reservoirs, and lead to novel ways to restore immune functions in HIV+ patients.
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Affiliation(s)
- Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University , Cleveland, OH , USA
| | - Souheil-Antoine Younes
- Department of Medicine, Division of Infectious Diseases, University Hospitals, Case Western Reserve University , Cleveland, OH , USA
| | | | - Aarthi Talla
- Department of Pathology, Case Western Reserve University , Cleveland, OH , USA
| | - David McDonald
- Department of Microbiology and Molecular Biology, School of Medicine, Case Western Reserve University , Cleveland, OH , USA
| | - Natarajan Bhaskaran
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University , Cleveland, OH , USA
| | - Alan D Levine
- Department of Pharmacology, School of Medicine, Case Western Reserve University , Cleveland, OH , USA
| | - Aaron Weinberg
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University , Cleveland, OH , USA
| | - Rafick P Sekaly
- Department of Pathology, Case Western Reserve University , Cleveland, OH , USA
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17
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Wu H, Chen Y, Liu H, Xu LL, Teuscher P, Wang S, Lu S, Dent AL. Follicular regulatory T cells repress cytokine production by follicular helper T cells and optimize IgG responses in mice. Eur J Immunol 2016; 46:1152-61. [PMID: 26887860 DOI: 10.1002/eji.201546094] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 01/06/2016] [Accepted: 02/10/2016] [Indexed: 11/08/2022]
Abstract
Follicular helper T (Tfh) cells provide crucial help to germinal center B (GCB) cells for proper antibody production, and a specialized subset of regulatory T cells, follicular regulatory T (Tfr) cells, modulate this process. However, Tfr-cell function in the GC is not well understood. Here, we define Tfr cells as a CD4(+) Foxp3(+) CXCR5(hi) PD-1(hi) CD25(low) TIGIT(high) T-cell population. Furthermore, we have used a novel mouse model ("Bcl6FC") to delete the Bcl6 gene in Foxp3(+) T cells and thus specifically deplete Tfr cells. Following immunization, Bcl6FC mice develop normal Tfh- and GCB-cell populations. However, Bcl6FC mice produce altered antigen-specific antibody responses, with reduced titers of IgG and significantly increased IgA. Bcl6FC mice also developed IgG antibodies with significantly decreased avidity to antigen in an HIV-1 gp120 "prime-boost" vaccine model. In an autoimmune lupus model, we observed strongly elevated anti-DNA IgA titers in Bcl6FC mice. Additionally, Tfh cells from Bcl6FC mice consistently produce higher levels of Interferon-γ, IL-10 and IL-21. Loss of Tfr cells therefore leads to highly abnormal Tfh-cell and GCB-cell responses. Overall, our study has uncovered unique regulatory roles for Tfr cells in the GC response.
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Affiliation(s)
- Hao Wu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yuxin Chen
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Hong Liu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Lin-Lin Xu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Paula Teuscher
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Shixia Wang
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shan Lu
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Alexander L Dent
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
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18
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Askenasy N. Mechanisms of autoimmunity in the non-obese diabetic mouse: effector/regulatory cell equilibrium during peak inflammation. Immunology 2016; 147:377-88. [PMID: 26749404 DOI: 10.1111/imm.12581] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/21/2015] [Accepted: 12/21/2015] [Indexed: 12/25/2022] Open
Abstract
Immune imbalance in autoimmune disorders such as type 1 diabetes may originate from aberrant activities of effector cells or dysfunction of suppressor cells. All possible defective mechanisms have been proposed for diabetes-prone species: (i) quantitative dominance of diabetogenic cells and decreased numbers of regulatory T cells, (ii) excessive aggression of effectors and defective function of suppressors, (iii) perturbed interaction between effector and suppressor cells, and (iv) variations in sensitivity to negative regulation. The experimental evidence available to date presents conflicting information on these mechanisms, with identification of perturbed equilibrium on the one hand and negation of critical role of each mechanism in propagation of diabetic autoimmunity on the other hand. In our analysis, there is no evidence that inherent abnormalities in numbers and function of effector and suppressor T cells are responsible for the immune imbalance responsible for propagation of type 1 diabetes as a chronic inflammatory process. Possibly, the experimental tools for investigation of these features of immune activity are still underdeveloped and lack sufficient resolution, in the presence of the extensive biological viability and functional versatility of effector and suppressor elements.
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Affiliation(s)
- Nadir Askenasy
- The Leah and Edward M. Frankel Laboratory of Experimental Bone Marrow Transplantation, Petach Tikva, Israel
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19
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González FB, Calmon-Hamaty F, Nô Seara Cordeiro S, Fernández Bussy R, Spinelli SV, D'Attilio L, Bottasso O, Savino W, Cotta-de-Almeida V, Villar SR, Pérez AR. Trypanosoma cruzi Experimental Infection Impacts on the Thymic Regulatory T Cell Compartment. PLoS Negl Trop Dis 2016; 10:e0004285. [PMID: 26745276 PMCID: PMC4706328 DOI: 10.1371/journal.pntd.0004285] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/16/2015] [Indexed: 11/18/2022] Open
Abstract
The dynamics of regulatory T cells in the course of Trypanosoma cruzi infection is still debated. We previously demonstrated that acute murine T. cruzi infection results in an impaired peripheral CD4+Foxp3+ T cell differentiation due to the acquisition of an abnormal Th1-like phenotype and altered functional features, negatively impacting on the course of infection. Moreover, T. cruzi infection induces an intense thymic atrophy. As known, the thymus is the primary lymphoid organ in which thymic-derived regulatory T cells, known as tTregs, differentiate. Considering the lack of available data about the effect of T. cruzi infection upon tTregs, we examined tTreg dynamics during the course of disease. We confirmed that T. cruzi infection induces a marked loss of tTreg cell number associated to cell precursor exhaustion, partially avoided by glucocorticoid ablation- and IL-2 survival factor depletion. At the same time, tTregs accumulate within the CD4 single-positive compartment, exhibiting an increased Ki-67/Annexin V ratio compared to controls. Moreover, tTregs enhance after the infection the expression of signature markers (CD25, CD62L and GITR) and they also display alterations in the expression of migration-associated molecules (α chains of VLAs and chemokine receptors) such as functional fibronectin-driven migratory disturbance. Taken together, we provide data demonstrating profound alterations in tTreg compartment during acute murine T. cruzi infection, denoting that their homeostasis is significantly affected. The evident loss of tTreg cell number may compromise the composition of tTreg peripheral pool, and such sustained alteration over time may be partially related to the immune dysregulation observed in the chronic phase of the disease.
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Affiliation(s)
- Florencia Belén González
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Flavia Calmon-Hamaty
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Synara Nô Seara Cordeiro
- Laboratory of Innovations in Therapy, Teaching and Bioproducts, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Rodrigo Fernández Bussy
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Silvana Virginia Spinelli
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Luciano D'Attilio
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Oscar Bottasso
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Wilson Savino
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Vinícius Cotta-de-Almeida
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Silvina Raquel Villar
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Ana Rosa Pérez
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
- * E-mail: ,
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20
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Jaberi-Douraki M, Pietropaolo M, Khadra A. Continuum model of T-cell avidity: Understanding autoreactive and regulatory T-cell responses in type 1 diabetes. J Theor Biol 2015; 383:93-105. [PMID: 26271890 DOI: 10.1016/j.jtbi.2015.07.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 07/22/2015] [Accepted: 07/31/2015] [Indexed: 12/21/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of insulin-secreting pancreatic β cells, leading to abolition of insulin secretion and onset of diabetes. Cytotoxic CD4(+) and CD8(+) T cells, activated by antigen presenting cells (APCs), are both implicated in disease onset and progression. Regulatory T cells (Tregs), on the other hand, play a leading role in regulating immunological tolerance and resistant homoeostasis in T1D by suppressing effector T cells (Teffs). Recent data indicates that after activation, conventional Teffs transiently produce interleukin IL-2, a cytokine that acts as a growth factor for both Teffs and Tregs. Tregs suppress Teffs through IL-2 deprivation, competition and Teff conversion into inducible Tregs (iTregs). To investigate the interactions of these components during T1D progression, a mathematical model of T-cell dynamics is developed as a predictor of β-cell loss, with the underlying hypothesis that avidity of Teffs and Tregs, i.e., the binding affinity of T-cell receptors to peptide-major histocompatibility complexes on host cells, is continuum. The model is used to infer a set of criteria that determines susceptibility to T1D in high risk subjects. Our findings show that diabetes onset is guided by the absence of Treg-to-Teff dominance at specific high avidities, rather than over the whole range of avidity, and that the lack of overall dominance of Teffs-to-Tregs over time is the underlying cause of the "honeymoon period", the remission phase observed in some T1D patients. The model also suggests that competition between Teffs and Tregs is more effective than Teff-induction into iTregs in suppressing Teffs, and that a prolonged full width at half maximum of IL-2 release is a necessary condition for curbing disease onset. Finally, the model provides a rationale for observing rapid and slow progressors of T1D based on modest heterogeneity in the kinetic parameters.
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Affiliation(s)
| | - Massimo Pietropaolo
- Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston 77030, Texas, USA
| | - Anmar Khadra
- Department of Physiology, McGill University, H3G 1Y6, Quebec, Montreal, Canada.
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21
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Pandiyan P, Zhu J. Origin and functions of pro-inflammatory cytokine producing Foxp3+ regulatory T cells. Cytokine 2015; 76:13-24. [PMID: 26165923 DOI: 10.1016/j.cyto.2015.07.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 12/12/2022]
Abstract
CD4(+)CD25(+)Foxp3(+) regulatory cells (Tregs) are a special lineage of cells central in the maintenance of immune homeostasis, and are targeted for human immunotherapy. They are conventionally associated with the production of classical anti-inflammatory cytokines such as IL-10, TGF-β and IL-35, consistent to their anti-inflammatory functions. However, emerging evidence show that they also express effector cytokines such as IFN-γ and IL-17A under inflammatory conditions. While some studies reveal that these pro-inflammatory cytokine producing Foxp3(+) regulatory cells retain their suppressive ability, others believe that these cells are dys-regulated and are associated with perpetuation of immunopathology. Therefore the development of these cells may challenge the efficacy of human Treg therapy. Mechanistically, toll-like receptor (TLR) ligands and the pro-inflammatory cytokine milieu have been shown to play important roles in the induction of effector cytokines in Tregs. Here we review the mechanisms of development and the possible functions of pro-inflammatory cytokine producing Foxp3+ Tregs.
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Affiliation(s)
- Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Jinfang Zhu
- Molecular and Cellular Immunoregulation Unit, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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22
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Bhaskaran N, Cohen S, Zhang Y, Weinberg A, Pandiyan P. TLR-2 Signaling Promotes IL-17A Production in CD4+CD25+Foxp3+ Regulatory Cells during Oropharyngeal Candidiasis. Pathogens 2015; 4:90-110. [PMID: 25790134 PMCID: PMC4384074 DOI: 10.3390/pathogens4010090] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/05/2015] [Accepted: 03/11/2015] [Indexed: 12/17/2022] Open
Abstract
Recent studies show that CD4+CD25+Foxp3+ regulatory cells (Tregs) produce effector cytokines under inflammatory conditions. However, the direct role of microbial agents that serve as toll-like receptor (TLR) ligands in the induction of effector cytokines in Tregs is less clear. Here we show that CD4+Foxp3+Tregs produce the effector cytokine IL-17A during oropharyngeal candidiasis (OPC) and inflammatory bowel disease in a TLR-2/Myd88 signaling dependent manner. TLR-2 ligands promote proliferation in Tregs in the presence and absence of TCR signals and inflammatory cytokines in vitro. The proliferation is directly dependent on TLR-2 expression in Tregs. Consistent with this, Tlr2−/− mice harbor fewer thymically derived Tregs and peripheral Tregs under homeostatic conditions in vivo. However, under Th17 inducing conditions, IL-6 and TLR-2 signaling both in Tregs as well as antigen presenting cells (APC) are critical for maximal ROR-γt and IL-17A up-regulation in Foxp3+ Tregs. The minimal and transient loss of Foxp3 expression and suppressive properties are due to the presence of IL-6 in the milieu, but not the direct effect of TLR-2 signaling in Tregs. Taken together, our data reveal that TLR-2 signaling promotes not only proliferation, but also IL-17A in Tregs, depending on the cytokine milieu. These IL-17A producing Tregs may be relevant in mucosal infections and inflammation.
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Affiliation(s)
- Natarajan Bhaskaran
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Samuel Cohen
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Yifan Zhang
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Aaron Weinberg
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
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23
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Bhaskaran N, Weinberg A, Pandiyan P. Th17 inflammation model of oropharyngeal candidiasis in immunodeficient mice. J Vis Exp 2015:52538. [PMID: 25742163 PMCID: PMC4354660 DOI: 10.3791/52538] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Oropharyngeal Candidiasis (OPC) disease is caused not only due to the lack of host immune resistance, but also the absence of appropriate regulation of infection-induced immunopathology. Although Th17 cells are implicated in antifungal defense, their role in immunopathology is unclear. This study presents a method for establishing oral Th17 immunopathology associated with oral candidal infection in immunodeficient mice. The method is based on reconstituting lymphopenic mice with in vitro cultured Th17 cells, followed by oral infection with Candida albicans (C. albicans). Results show that unrestrained Th17 cells result in inflammation and pathology, and is associated with several measurable read-outs including weight loss, pro-inflammatory cytokine production, tongue histopathology and mortality, showing that this model may be valuable in studying OPC immunopathology. Adoptive transfer of regulatory cells (Tregs) controls and reduces the inflammatory response, showing that this model can be used to test new strategies to counteract oral inflammation. This model may also be applicable in studying oral Th17 immunopathology in general in the context of other oral diseases.
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Affiliation(s)
- Natarajan Bhaskaran
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University
| | - Aaron Weinberg
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University
| | - Pushpa Pandiyan
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University;
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Simonetta F, Gestermann N, Bloquet S, Bourgeois C. Interleukin-7 optimizes FOXP3+CD4+ regulatory T cells reactivity to interleukin-2 by modulating CD25 expression. PLoS One 2014; 9:e113314. [PMID: 25485946 PMCID: PMC4259569 DOI: 10.1371/journal.pone.0113314] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/22/2014] [Indexed: 12/04/2022] Open
Abstract
The vast majority of Foxp3 regulatory T cells (Treg) exhibits constitutive expression of CD25 (IL-2Rα), which allows the constitution of the high affinity IL-2Rαβγ receptor, ensuring efficient IL-2 binding by Treg. Maintenance of CD25 expression at Treg surface depends on both cell intrinsic factors and environmental stimuli such as IL-2 itself. Whether other factors can participate to maintenance of CD25 expression in vivo is at present unknown. In the present work we demonstrated that IL-7, a gamma-chain cytokine exerting a crucial role in T cell development and homeostasis, is able and necessary to sustain the expression of high levels of CD25 at Treg surface. We demonstrated that, during in vitro cultures performed in the absence of IL-2, IL-7 is able to sustain CD25 expression at Treg surface through a transcriptional mechanism. By studying mice in which IL-7 signaling is either genetically impaired or increased and by employing adoptive transfer murine models, we demonstrated that IL-7 is necessary for sustained expression of CD25 at Treg surface in vivo. To ascertain the biological impact of IL-7 mediated modulation of CD25 expression, we demonstrated that IL-7 modulation of CD25 expression at Treg surface affected their ability to efficiently bind IL-2 and transduce IL-2 signaling. Finally, we demonstrated that IL-7 dependent modulation of CD25 associated with potentiated IL-2 induced expansion of Treg in vivo. Collectively, our results identify IL-7 as a necessary factor contributing to sustained CD25 expression at Treg surface in vivo thereby affecting their ability to efficiently react to IL-2.
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Affiliation(s)
- Federico Simonetta
- INSERM, U1012, Le Kremlin-Bicêtre, France
- Univ Paris-SUD, UMR-S1012, Le Kremlin-Bicêtre, France
- Division of Hematology, Department of Medical Specialties, Geneva University Hospitals, Geneva, Switzerland
| | - Nicolas Gestermann
- INSERM, U1012, Le Kremlin-Bicêtre, France
- Univ Paris-SUD, UMR-S1012, Le Kremlin-Bicêtre, France
| | - Stéphane Bloquet
- Animalerie centrale, Faculté de Médecine Paris-Sud, Univ Paris-Sud, Le Kremlin-Bicêtre, France
| | - Christine Bourgeois
- INSERM, U1012, Le Kremlin-Bicêtre, France
- Univ Paris-SUD, UMR-S1012, Le Kremlin-Bicêtre, France
- * E-mail:
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25
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Abstract
UNLABELLED Regulatory T (Treg) cells are important in the maintenance of self-tolerance, and the depletion of Treg cells correlates with autoimmune development. It has been shown that type I interferon (IFN) responses induced early in the infection of mice can drive memory (CD44hi) CD8 and CD4 T cells into apoptosis, and we questioned here whether the apoptosis of CD44-expressing Treg cells might be involved in the infection-associated autoimmune development. Instead, we found that Treg cells were much more resistant to apoptosis than CD44hi CD8 and CD4 T cells at days 2 to 3 after lymphocytic choriomeningitis virus infection, when type I IFN levels are high. The infection caused a downregulation of the interleukin-7 (IL-7) receptor, needed for survival of conventional T cells, while increasing on Treg cells the expression of the high-affinity IL-2 receptor, needed for STAT5-dependent survival of Treg cells. The stably maintained Treg cells early during infection may explain the relatively low incidence of autoimmune manifestations among infected patients. IMPORTANCE Autoimmune diseases are controlled in part by regulatory T cells (Treg) and are thought to sometimes be initiated by viral infections. We tested the hypothesis that Treg may die off at early stages of infection, when virus-induced factors kill other lymphocyte types. Instead, we found that Treg resisted this cell death, perhaps reducing the tendency of viral infections to cause immune dysfunction and induce autoimmunity.
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26
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Xie L, Choudhury GR, Winters A, Yang SH, Jin K. Cerebral regulatory T cells restrain microglia/macrophage-mediated inflammatory responses via IL-10. Eur J Immunol 2014; 45:180-91. [PMID: 25329858 DOI: 10.1002/eji.201444823] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 08/29/2014] [Accepted: 10/13/2014] [Indexed: 12/17/2022]
Abstract
Forkhead box P3 (Foxp3)(+) regulatory T (Treg) cells maintain the immune tolerance and prevent inflammatory responses in the periphery. However, the presence of Treg cells in the CNS under steady state has not been studied. Here, for the first time, we show a substantial TCRαβ (+) CD4(+) Foxp3(+) T-cell population (cerebral Treg cells) in the rat cerebrum, constituting more than 15% of the cerebral CD4(+) T-cell compartment. Cerebral Treg cells showed an activated/memory phenotype and expressed many Treg-cell signature genes at higher levels than peripheral Treg cells. Consistent with their activated/memory phenotype, cerebral Treg cells robustly restrained the LPS-induced inflammatory responses of brain microglia/macrophages, suggesting a role in maintaining the cerebral homeostasis by inhibiting the neuroinflammation. In addition, brain astrocytes were the helper cells that sustained Foxp3 expression in Treg cells through IL-2/STAT5 signaling, showing that the interaction between astrocytes and Treg cells contributes to the maintenance of Treg-cell identity in the brain. Taken together, our work represents the first study to characterize the phenotypic and functional features of Treg cells in the rat cerebrum. Our data have provided a novel insight for the contribution of Treg cells to the immunosurveillance and immunomodulation in the cerebrum under steady state.
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Affiliation(s)
- Luokun Xie
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
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Attridge K, Walker LSK. Homeostasis and function of regulatory T cells (Tregs) in vivo: lessons from TCR-transgenic Tregs. Immunol Rev 2014; 259:23-39. [PMID: 24712457 PMCID: PMC4237543 DOI: 10.1111/imr.12165] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The identification of CD25 and subsequently Forkhead box protein 3 (Foxp3) as markers for regulatory T cells (Tregs) has revolutionized our ability to explore this population experimentally. In a similar vein, our understanding of antigen-specific Treg responses in vivo owes much to the fortuitous generation of T-cell receptor (TCR)-transgenic Tregs. This has permitted tracking of Tregs with a defined specificity in vivo, facilitating analysis of how encounter with cognate antigen shapes Treg homeostasis and function. Here, we review the key lessons learned from a decade of analysis of TCR-transgenic Tregs and set this in the broader context of general progress in the field. Use of TCR-transgenic Tregs has led to an appreciation that Tregs are a highly dynamic proliferative population in vivo, rather than an anergic population as they were initially portrayed. It is now clear that Treg homeostasis is positively regulated by encounter with self-antigen expressed on peripheral tissues, which is likely to be relevant to the phenomenon of peripheral repertoire reshaping that has been described for Tregs and the observation that the Treg TCR specificities vary by anatomical location. Substantial evidence has also accumulated to support the role of CD28 costimulation and interleukin-2 in Treg homeostasis. The availability of TCR-transgenic Tregs has enabled analysis of Treg populations that are sufficient or deficient in particular genes, without the comparison being confounded by repertoire alterations. This approach has yielded insights into genes required for Treg function in vivo, with particular progress being made on the role of ctla-4 in this context. As the prospect of manipulating Treg populations in the clinic becomes reality, a full appreciation of the rules governing their homeostasis will prove increasingly important.
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Affiliation(s)
- Kesley Attridge
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
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28
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Lin S, Yang X, Liang D, Zheng SG. Treg cells: a potential regulator for IL-22 expression? INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2014; 7:474-80. [PMID: 24551268 PMCID: PMC3925892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/03/2014] [Indexed: 06/03/2023]
Abstract
Inteleurkin-22 (IL-22) is a IL-10 family cytokine member and is mainly produced by innate lymphoid cells (ILCs), Th17 cells, and Th22 cells. Previous studies have indicated that IL-23 and several transcription factors, including STAT3, RORγt, and the AhR are important stimulus. Recently, there is emerging evidence that Tregs can regulate IL-22 expression. In the review, we discuss the updated advancement on Tregs function and its regulatory role on IL-22 expression.
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Affiliation(s)
- Shuman Lin
- Medical College at Sun Yat‑Sen UniversityGuangzhou, 510008, P. R. China
| | - Xuyan Yang
- Department of Rheumatology, Second Affiliated Hospital, College of Medicine, Zhejiang UniversityHangzhou, 310009, P. R. China
| | - Dian Liang
- Medical College at Sun Yat‑Sen UniversityGuangzhou, 510008, P. R. China
| | - Song Guo Zheng
- Division of Rheumatology, Department of Medicine at Penn State University Hershey College of MedicineHershey, 17033, USA
- Institute of Immunology, Shanghai East Hospital at Tongji UniversityShanghai, 200120, P. R. China
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29
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Kaminitz A, Mizrahi K, Askenasy N. Surge in regulatory T cells does not prevent onset of hyperglycemia in NOD mice: immune profiles do not correlate with disease severity. Autoimmunity 2013; 47:105-12. [PMID: 24328490 DOI: 10.3109/08916934.2013.866103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Immune profiling of non-obese diabetic (NOD) is a widely employed tool to assess the mechanisms of inflammatory insulitis. Our analysis of the female NOD colony revealed similar distribution of lymphoid lineages to wild type mice, and at various ages of prediabetic and diabetic mice. The profiles of mesenteric and pancreatic lymph nodes differ and often change reciprocally due to directed migration of T cells towards the site of inflammation. Significant events in our colony include early decline in CD4(+)CD25(+)CD62L(+) Treg, accompanied by gradual increase in CD4(+)CD25(+)FoxP3(+) Treg in peripheral lymphoid organs and pancreatic infiltrates. Impressively, aged euglycemic mice display significant transient rise in CD4(+)CD25(-)FoxP3(+) Treg in the thymus, pancreas and draining lymph nodes. A significant difference was superior viability of effector and suppressor cells from new onset diabetics in the presence of high interleukin-2 (IL-2) concentrations in vitro as compared to cells of prediabetic mice. Overall, we found no correlation between FoxP3(+) Treg in the pancreatic lymph nodes and the inflammatory scores of individual NOD mice. CD25(-)FoxP3(+) Treg are markedly increased in the pancreatic infiltrates in late stages of inflammation, possibly an effort to counteract destructive insulitis. Considering extensive evidence that Treg in aged NOD mice are functionally sufficient, quantitative profiling evolves as an unreliable tool to assess mechanism and causes of inflammation under baseline conditions. Immune profiles are modulated by thymic output, cell migration, shedding of markers, proliferation, survival and in-situ evolution of regulatory cells.
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Affiliation(s)
- Ayelet Kaminitz
- Frankel Laboratory, Center for Stem Cell Research, Department of Pediatric Hematology-Oncology, Schneider Children's Medical Center of Israel , Petach Tikva , Israel
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30
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Lalive PH, Benkhoucha M, Tran NL, Kreutzfeldt M, Merkler D, Santiago-Raber ML. TLR7 signaling exacerbates CNS autoimmunity through downregulation of Foxp3+ Treg cells. Eur J Immunol 2013; 44:46-57. [PMID: 24018482 DOI: 10.1002/eji.201242985] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 08/02/2013] [Accepted: 09/06/2013] [Indexed: 12/21/2022]
Abstract
The innate Toll-like receptor 7 (TLR7) detects infections by recognizing viral and bacterial single-stranded RNA. In addition to pathogen-derived RNA, immune cells expressing high levels of TLR7, such as B cells and dendritic cells (DCs), can be activated by self-RNA. During myelin-induced experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, TLR7 expression is increased within the central nervous system (CNS). To define the contribution of TLR7 to the development of EAE, we evaluated the course of the disease in C57BL/6-Tlr7-deficient mice compared with that in WT mice and found that TLR7-deficient mice had decreased disease severity. This protection was associated with decreased myelin oligodendrocyte glycoprotein-specific T-cell activation by primed DCs, decreased circulating autoantibodies, attenuated inflammation within the CNS, and increased Foxp3(+) regulatory T cells in the periphery and in the CNS. In conclusion, we show that TLR7 is involved in the maintenance of autoimmunity in the pathogenesis of EAE.
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Affiliation(s)
- Patrice H Lalive
- Faculty of Medicine, Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland; Division of Neurology, Department of Clinical Neurosciences, Neuroimmunology Laboratory, Geneva University Hospital, Geneva, Switzerland; Division of Laboratory Medicine, Department of Genetic and Laboratory Medicine, Geneva University Hospital, Geneva, Switzerland
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31
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Younas M, Hue S, Lacabaratz C, Guguin A, Wiedemann A, Surenaud M, Beq S, Croughs T, Lelièvre JD, Lévy Y. IL-7 modulates in vitro and in vivo human memory T regulatory cell functions through the CD39/ATP axis. THE JOURNAL OF IMMUNOLOGY 2013; 191:3161-8. [PMID: 23966629 DOI: 10.4049/jimmunol.1203547] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The heterogeneity of human regulatory T cells (Tregs) may explain the discrepancies between studies on Tregs in physiology and pathology. Contrasting effects of IL-7 on the expansion and survival of human Tregs were reported. Therefore, we investigated the effects of IL-7 on the phenotype and function of well-characterized populations of human Tregs. We show that IL-7 signals via the CD127 receptor on naive, memory, and activated memory Tregs sorted from the blood of healthy donors, but it does not affect their proliferation. In contrast, IL-7 affects their suppressive capacities differently. This effect was modest on naive Tregs but was dramatic (90%) on memory Tregs. We provide evidence that IL-7 exerts a synergistic effect through downmodulation of the ectoenzyme CD39, which converts ATP to ADP/AMP, and an increase in ATP receptor P2X7. Both effects lead to an increase in the ATP-mediated effect, tipping the balance to favor Th17 conversion. Using an IL-7 therapeutic study, we show that IL-7 exerts the same effects in vitro and in vivo in HIV-infected individuals. Globally, our data show that IL-7 negatively regulates Tregs and contributes to increase the number of tools that may affect Treg function in pathology.
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Affiliation(s)
- Mehwish Younas
- INSERM U955, Institut Mondor de Recherche Biomédicale, 94010 Créteil, France
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32
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Dorsey NJ, Chapoval SP, Smith EP, Skupsky J, Scott DW, Keegan AD. STAT6 controls the number of regulatory T cells in vivo, thereby regulating allergic lung inflammation. THE JOURNAL OF IMMUNOLOGY 2013; 191:1517-28. [PMID: 23825312 DOI: 10.4049/jimmunol.1300486] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
STAT6 plays a central role in IL-4-mediated allergic responses. Several studies indicate that regulatory T cells (Tregs) can be modulated by IL-4 in vitro. We previously showed that STAT6(-/-) mice are highly resistant to allergic lung inflammation even when wild-type Th2 effectors were provided and that they have increased numbers of Tregs. However, the role of STAT6 in modulating Tregs in vivo during allergic lung inflammation has not been thoroughly investigated. To examine Treg and STAT6 interaction during allergic inflammation, STAT6(-/-), STAT6xRAG2(-/-), and RAG2(-/-) mice were subjected to OVA sensitization and challenge following adoptive transfer of OVA-specific, wild-type Th2 effectors with or without prior Treg depletion/inactivation, using anti-CD25 (PC61). As expected, STAT6(-/-) mice were highly resistant to airway inflammation and remodeling. In contrast, allergic lung inflammation was partially restored in STAT6(-/-) mice treated with PC61 to levels observed in STAT6xRAG2(-/-) mice. In some cases, STAT6xRAG2(-/-) mice were also given natural Tregs along with Th2 effectors. Adoptive transfer of natural Tregs caused a substantial reduction in bronchoalveolar lavage eosinophil composition and suppressed airway remodeling and T cell migration into the lung in STAT6xRAG2(-/-) mice to levels comparable to those in STAT6(-/-) mice. These results demonstrate the STAT6-dependent suppression of Tregs in vivo to promote allergic airway inflammation.
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Affiliation(s)
- Nicolas J Dorsey
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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33
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Enhanced killing activity of regulatory T cells ameliorates inflammation and autoimmunity. Autoimmun Rev 2013; 12:972-5. [PMID: 23684702 DOI: 10.1016/j.autrev.2013.04.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 04/03/2013] [Indexed: 12/25/2022]
Abstract
Regulatory T cells (Treg) are pivotal suppressor elements in immune homeostasis with potential therapeutic applications in inflammatory and autoimmune disorders. Using Treg as vehicles for targeted immunomodulation, a short-lived Fas-ligand (FasL) chimeric protein (killer Treg) was found efficient in preventing the progression of autoimmune insulitis in NOD mice, and amelioration of chronic colitis and graft versus host disease. The main mechanisms of disease suppression by killer Treg are: a) in the acute phase induction of apoptosis in effector cells at the site of inflammation decreases the pathogenic burden, and b) persistent increase in FoxP3⁺ Treg with variable CD25 co-expression induced by FasL sustains disease suppression over extended periods of time. Reduced sensitivity of Treg to receptor-mediated apoptosis under inflammatory conditions makes them optimal vehicles for targeted immunotherapy using apoptotic agents.
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34
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Kashiwakura Y, Sakurai D, Kanno Y, Hashiguchi M, Kobayashi A, Kurosu A, Tokudome S, Kobata T, Kojima H. CD2-mediated regulation of peripheral CD4(+) CD25(+) regulatory T-cell apoptosis accompanied by down-regulation of Bim. Immunology 2013; 139:48-60. [PMID: 23278598 PMCID: PMC3634538 DOI: 10.1111/imm.12054] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 12/13/2012] [Accepted: 12/14/2012] [Indexed: 01/06/2023] Open
Abstract
Extensive studies on CD4(+) CD25(+) regulatory T (Treg) cells suggest that they are important in regulating immune responses. However, mechanisms of peripheral Treg cell homeostasis are unknown. We found that stromal cells isolated from secondary lymphoid organs such as spleen and lymph nodes could support the survival of Treg cells. This was dependent on CD2 engagement and a direct interaction between Treg cells and stromal cells. In the presence of stromal cells, Bim, a pro-apoptotic factor, was partially decreased in Treg cells. This effect could be inhibited by anti-CD2 blocking antibodies, indicating that stimulation through CD2 on Treg cells regulates Bim expression, which may be relevant to Treg cell apoptosis. Therefore, Treg cell interactions with stromal cells through CD2 may be essential for Treg cell survival. Surprisingly, the expression of CD2 ligands on stromal cells was not detected. Hence, it is not clear how CD2 on Treg cells contributes to a direct interaction with the stromal cells and participates in survival support for Treg cells. Taken together, CD2 stimuli were mandatory for Treg cell survival with reduced Bim expression, but CD2 may not function as a direct receptor for molecules on stromal cells.
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Affiliation(s)
- Yuji Kashiwakura
- Department of Immunology, Dokkyo Medical University School of Medicine, Mibu, Tochigi, Japan
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35
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Smith KA. The molecular mechanisms of regulatory T cell immunosuppression. Front Immunol 2012; 3:379. [PMID: 23248628 PMCID: PMC3522108 DOI: 10.3389/fimmu.2012.00379] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 11/27/2012] [Indexed: 02/03/2023] Open
Affiliation(s)
- Kendall A Smith
- Division of Immunology, Department of Medicine, Weill Medical College, Cornell University New York, NY, USA
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36
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Langenhorst D, Gogishvili T, Ribechini E, Kneitz S, McPherson K, Lutz MB, Hünig T. Sequential induction of effector function, tissue migration and cell death during polyclonal activation of mouse regulatory T-cells. PLoS One 2012; 7:e50080. [PMID: 23226238 PMCID: PMC3511437 DOI: 10.1371/journal.pone.0050080] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/16/2012] [Indexed: 11/18/2022] Open
Abstract
The ability of CD4(+)Foxp3(+) regulatory T-cells (Treg) to produce interleukin (IL)-10 is important for the limitation of inflammation at environmental interfaces like colon or lung. Under steady state conditions, however, few Tregs produce IL-10 ex vivo. To investigate the origin and fate of IL-10 producing Tregs we used a superagonistic mouse anti-mouse CD28 mAb (CD28SA) for polyclonal in vivo stimulation of Tregs, which not only led to their numeric expansion but also to a dramatic increase in IL-10 production. IL-10 secreting Tregs strongly upregulated surface receptors associated with suppressive function as compared to non-producing Tregs. Furthermore, polyclonally expanding Tregs shifted their migration receptor pattern after activation from a CCR7(+)CCR5(-) lymph node-seeking to a CCR7(-)CCR5(+) inflammation-seeking phenotype, explaining the preferential recruitment of IL-10 producers to sites of ongoing immune responses. Finally, we observed that IL-10 producing Tregs from CD28SA stimulated mice were more apoptosis-prone in vitro than their IL-10 negative counterparts. These findings support a model where prolonged activation of Tregs results in terminal differentiation towards an IL-10 producing effector phenotype associated with a limited lifespan, implicating built-in termination of immunosuppression.
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MESH Headings
- Animals
- Antibodies/immunology
- Antibodies/pharmacology
- Apoptosis/drug effects
- CD28 Antigens/agonists
- CD28 Antigens/immunology
- Cell Differentiation/drug effects
- Cell Movement/drug effects
- Cells, Cultured
- Clone Cells
- Gene Expression/drug effects
- Inflammation/immunology
- Inflammation/metabolism
- Interleukin-10/biosynthesis
- Interleukin-10/immunology
- Lymph Nodes/cytology
- Lymph Nodes/drug effects
- Lymph Nodes/immunology
- Lymphocyte Activation/drug effects
- Mice
- Mice, Inbred C57BL
- Receptors, CCR5/genetics
- Receptors, CCR5/immunology
- Receptors, CCR7/genetics
- Receptors, CCR7/immunology
- T-Lymphocytes, Cytotoxic/cytology
- T-Lymphocytes, Cytotoxic/drug effects
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Regulatory/cytology
- T-Lymphocytes, Regulatory/drug effects
- T-Lymphocytes, Regulatory/immunology
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Affiliation(s)
- Daniela Langenhorst
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Tea Gogishvili
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Eliana Ribechini
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Susanne Kneitz
- Interdisciplinary Centre for Clinical Research (IZKF), University of Würzburg, Würzburg, Germany
| | - Kirsty McPherson
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
- Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Australia
| | - Manfred B. Lutz
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Thomas Hünig
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
- * E-mail:
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37
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Claus C, Riether C, Schürch C, Matter MS, Hilmenyuk T, Ochsenbein AF. CD27 signaling increases the frequency of regulatory T cells and promotes tumor growth. Cancer Res 2012; 72:3664-76. [PMID: 22628427 DOI: 10.1158/0008-5472.can-11-2791] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Signaling of the TNF receptor superfamily member CD27 activates costimulatory pathways to elicit T- and B-cell responses. CD27 signaling is regulated by the expression of its ligand CD70 on subsets of dendritic cells and lymphocytes. Here, we analyzed the role of the CD27-CD70 interaction in the immunologic control of solid tumors in Cd27-deficient mice. In tumor-bearing wild-type mice, the CD27-CD70 interaction increased the frequency of regulatory T cells (Tregs), reduced tumor-specific T-cell responses, increased angiogenesis, and promoted tumor growth. CD27 signaling reduced apoptosis of Tregs in vivo and induced CD4(+) effector T cells (Teffs) to produce interleukin-2, a key survival factor for Tregs. Consequently, the frequency of Tregs and growth of solid tumors were reduced in Cd27-deficient mice or in wild-type mice treated with monoclonal antibody to block CD27 signaling. Our findings, therefore, provide a novel mechanism by which the adaptive immune system enhances tumor growth and may offer an attractive strategy to treat solid tumors.
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Affiliation(s)
- Christina Claus
- Tumor Immunology, Department of Clinical Research, University of Bern, Bern, Switzerland
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38
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Simonetta F, Gestermann N, Martinet KZ, Boniotto M, Tissières P, Seddon B, Bourgeois C. Interleukin-7 influences FOXP3+CD4+ regulatory T cells peripheral homeostasis. PLoS One 2012; 7:e36596. [PMID: 22586481 PMCID: PMC3346843 DOI: 10.1371/journal.pone.0036596] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/10/2012] [Indexed: 01/07/2023] Open
Abstract
Mechanisms governing peripheral CD4+ FOXP3+ regulatory T cells (Treg) survival and homeostasis are multiple suggesting tight and complex regulation of regulatory T cells homeostasis. Some specific factors, such as TGF-β, interleukin-2 (IL-2) and B7 costimulatory molecules have been identified as essentials for maintenance of the peripheral Treg compartment. Conversely, Treg dependency upon classical T cell homeostatic factors such as IL-7 is still unclear. In this work, we formally investigated the role of IL-7 in Treg homeostasis in vivo in murine models. We demonstrated that IL-7 availability regulated the size of peripheral Treg cell pool and thus paralleled the impact of IL-7 on conventional T cell pool. Moreover, we showed that IL-7 administration increased Treg cell numbers by inducing thymic-independent Treg peripheral expansion. Importantly the impact of IL-7 on Treg expansion was detected whether conventional T cells were present or absent as IL-7 directly participates to the peripheral expansion of Treg after adoptive transfer into lymphopenic hosts. Our results definitively identify IL-7 as a central factor contributing to Treg peripheral homeostasis, thus reassembling Treg to other T cell subsets in respect of their need for IL-7 for their peripheral maintenance.
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Affiliation(s)
- Federico Simonetta
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
| | - Nicolas Gestermann
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
| | - Kim Zita Martinet
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
| | - Michele Boniotto
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
| | - Pierre Tissières
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
| | - Benedict Seddon
- Division of Immune Cell Biology, National Institute for Medical Research, The Ridgeway, London, United Kingdom
| | - Christine Bourgeois
- INSERM, Le Kremlin-Bicêtre, France
- Université of Paris, Le Kremlin-Bicêtre, France
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Wang X, Szymczak-Workman AL, Gravano DM, Workman CJ, Green DR, Vignali DAA. Preferential control of induced regulatory T cell homeostasis via a Bim/Bcl-2 axis. Cell Death Dis 2012; 3:e270. [PMID: 22318539 PMCID: PMC3288351 DOI: 10.1038/cddis.2012.9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Apoptosis has an essential role in controlling T cell homeostasis, especially during the contraction phase of an immune response. However, its contribution to the balance between effector and regulatory populations remains unclear. We found that Rag1−/− hosts repopulated with Bim−/− conventional CD4+ T cells (Tconv) resulted in a larger induced regulatory T cell (iTreg) population than mice given wild-type (WT) Tconv. This appears to be due to an increased survival advantage of iTregs compared with activated Tconv in the absence of Bim. Downregulation of Bcl-2 expression and upregulation of Bim expression were more dramatic in WT iTregs than activated Tconv in the absence of IL-2 in vitro. The iTregs generated following Tconv reconstitution of Rag1−/− hosts exhibited lower Bcl-2 expression and higher Bim/Bcl-2 ratio than Tconv, which indicates that iTregs were in an apoptosis-prone state in vivo. A significant proportion of the peripheral iTreg pool exhibits low Bcl-2 expression indicating increased sensitivity to apoptosis, which may be a general characteristic of certain Treg subpopulations. In summary, our data suggest that iTregs and Tconv differ in their sensitivity to apoptotic stimuli due to their altered ratio of Bim/Bcl-2 expression. Modulating the apoptosis pathway may provide novel therapeutic approaches to alter the balance between effector T cells and Tregs.
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Affiliation(s)
- X Wang
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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40
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Thorborn GS, Pomeroy L, Ishohanni H, Peters BS, Vyakarnam A. Elevated effector cell sensitivity to Treg-cell suppression that is not associated with reduced Th17-cell expression distinguishes HIV+asymptomatic subjects from progressors. Eur J Immunol 2011; 42:138-46. [DOI: 10.1002/eji.201141426] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 09/06/2011] [Accepted: 10/06/2011] [Indexed: 11/12/2022]
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Pandiyan P, Zheng L, Lenardo MJ. The molecular mechanisms of regulatory T cell immunosuppression. Front Immunol 2011; 2:60. [PMID: 22566849 PMCID: PMC3342245 DOI: 10.3389/fimmu.2011.00060] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 10/19/2011] [Indexed: 12/22/2022] Open
Abstract
CD4⁺CD25⁺Foxp3⁺ T lymphocytes, known as regulatory T cells or T(regs), have been proposed to be a lineage of professional immune suppressive cells that exclusively counteract the effects of the immunoprotective "helper" and "cytotoxic" lineages of T lymphocytes. Here we discuss new concepts on the mechanisms and functions of T(regs). There are several key points we emphasize: 1. Tregs exert suppressive effects both directly on effector T cells and indirectly through antigen-presenting cells; 2. Regulation can occur through a novel mechanism of cytokine consumption to regulate as opposed to the usual mechanism of cytokine/chemokine production; 3. In cases where CD4⁺ effector T cells are directly inhibited by T(regs), it is chiefly through a mechanism of lymphokine withdrawal apoptosis leading to polyclonal deletion; and 4. Contrary to the current view, we discuss new evidence that T(regs), similar to other T-cells lineages, can promote protective immune responses in certain infectious contexts (Chen et al., 2011; Pandiyan et al., 2011). Although these points are at variance to varying degrees with the standard model of T(reg) behavior, we will recount developing findings that support these new concepts.
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Affiliation(s)
- Pushpa Pandiyan
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health Bethesda, MD, USA.
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42
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Tian L, Altin JA, Makaroff LE, Franckaert D, Cook MC, Goodnow CC, Dooley J, Liston A. Foxp3⁺ regulatory T cells exert asymmetric control over murine helper responses by inducing Th2 cell apoptosis. Blood 2011; 118:1845-53. [PMID: 21715314 PMCID: PMC3158716 DOI: 10.1182/blood-2011-04-346056] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 06/12/2011] [Indexed: 12/31/2022] Open
Abstract
Foxp3(+) regulatory T cells play a pivotal role in maintaining self-tolerance and immune homeostasis. In the absence of regulatory T cells, generalized immune activation and multiorgan T cell-driven pathology occurs. Although the phenomenon of immunologic control by Foxp3(+) regulatory T cells is well recognized, the comparative effect over different arms of the immune system has not been thoroughly investigated. Here, we generated a cohort of mice with a continuum of regulatory T-cell frequencies ranging from physiologic levels to complete deficiency. This titration of regulatory T-cell depletion was used to determine how different effector subsets are controlled. We found that in vivo Foxp3(+) regulatory T-cell frequency had a proportionate relationship with generalized T-cell activation and Th1 magnitude, but it had a surprising disproportionate relationship with Th2 magnitude. The asymmetric regulation was associated with efficient suppression of Th2 cells through additional regulations on the apoptosis rate in Th2 cells and not Th1 cells and could be replicated by CTLA4-Ig or anti-IL-2 Ab. These results indicate that the Th2 arm of the immune system is under tighter control by regulatory T cells than the Th1 arm, suggesting that Th2-driven diseases may be more responsive to regulatory T-cell manipulation.
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Zhan Y, Zhang Y, Gray D, Carrington EM, Bouillet P, Ko HJ, O’Reilly L, Wicks IP, Strasser A, Lew AM. Defects in the Bcl-2-regulated apoptotic pathway lead to preferential increase of CD25 low Foxp3+ anergic CD4+ T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 187:1566-77. [PMID: 21742968 PMCID: PMC3150360 DOI: 10.4049/jimmunol.1100027] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Defects in the Bcl-2-regulated apoptotic pathway inhibit the deletion of self-reactive T cells. What is unresolved, however, is the nature and fate of such self-reactive T cells escaping deletion. In this study, we report that mice with such defects contained increased numbers of CD25(low)Foxp3(+) cells in the thymus and peripheral lymph tissues. The increased CD25(low)Foxp3(+) population contained a large fraction of cells bearing self-reactive TCRs, evident from a prominent increase in self-superantigen-specific Foxp3(+)Vβ5(+)CD4(+) T cells in BALB/c Bim(-/-) mice compared with control animals. The survival rate of the expanded CD25(low)Foxp3(+) cells was similar to that of CD25(high)Foxp3(+) CD4 T cells in vitro and in vivo. IL-2R stimulation, but not TCR ligation, upregulated CD25 on CD25(low)Foxp3(+)CD4(+) T cells in vitro and in vivo. The expanded CD25(low)Foxp3(+)CD4(+) T cells from Bim(-/-) mice were anergic but also had weaker regulatory function than CD25(high)Foxp3(+) CD4(+) T cells from the same mice. Analysis of Bim(-/-) mice that also lacked Fas showed that the peripheral homeostasis of this expanded population was in part regulated by this death receptor. In conclusion, these results show that self-reactive T cell escapes from thymic deletion in mice defective in the Bcl-2-regulated apoptotic pathway upregulate Foxp3 and become unresponsive upon encountering self-Ag without necessarily gaining potent regulatory function. This clonal functional diversion may help to curtail autoaggressiveness of escaped self-reactive CD4(+) T cells and thereby safeguard immunological tolerance.
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Affiliation(s)
- Yifan Zhan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Yuxia Zhang
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Daniel Gray
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Emma M Carrington
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Philippe Bouillet
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Hyun-Ja Ko
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Lorraine O’Reilly
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Ian P Wicks
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Andreas Strasser
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Andrew M Lew
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
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Chakraborty T, Bose A, Barik S, Goswami KK, Banerjee S, Goswami S, Ghosh D, Roy S, Chakraborty K, Sarkar K, Baral R. Neem leaf glycoprotein inhibits CD4+CD25+Foxp3+ Tregs to restrict murine tumor growth. Immunotherapy 2011; 3:949-69. [DOI: 10.2217/imt.11.81] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Background: The presence of Tregs in tumors is associated with compromised tumor-specific immune responses and has a clear negative impact on survival of cancer patients. Thus, downregulation of Tregs is considered as a promising cancer immunotherapeutic approach. We have reported previously that neem leaf glycoprotein (NLGP) prophylaxis restricts tumor growth in mice by immune activation. In continuation, here, involvement of NLGP in the modulation of Tregs in association with tumor growth restriction is investigated. Results: NLGP downregulates CD4+CD25+Foxp3+ Tregs within tumors. NLGP-mediated downregulation of CCR4 along with its ligand CCL22 restricts Treg migration at the tumor site. NLGP is not apoptotic to Tregs but significantly downregulates the expression of Foxp3, CTLA4 and GITR. It also reverses the functional impairment of T-effector cells by Tregs, in terms of IFN-γ secretion, cellular proliferation and tumor cell cytotoxicity. NLGP also facilitates reconditioning of tumor microenvironment (hostile) by increasing IFN-γ and IL-12 but decreasing IL-10, TGF-β, VEGF and IDO, creating an antitumor niche. Interaction between Foxp3, p-NFATc3 and p-Smad2/3, needed for successful Treg function, is also inhibited by NLGP. Conclusion: All of these coordinated events might result in inhibition of Treg associated-tumor growth and therefore increased survivability of mice having NLGP treatment before or/and after tumor inoculation. Thus, the possibility of NLGP being an excellent tool as a T-cell anergy breaker by abrogating the suppressor functions of Tregs in cancer needs to be explored further in the clinic.
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Affiliation(s)
- Tathagata Chakraborty
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Anamika Bose
- Department of Molecular Medicine, Bose Institute, CIT Scheme, Kolkata, India
| | - Subhasis Barik
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Kuntal Kanti Goswami
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Saptak Banerjee
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Shyamal Goswami
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Diptendu Ghosh
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | - Soumyabrata Roy
- Department of Immunoregulation & Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, SP Mukherjee Road, Kolkata 700026, India
| | | | - Koustav Sarkar
- Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA, USA
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Kaminitz A, Yolcu ES, Askenasy EM, Stein J, Yaniv I, Shirwan H, Askenasy N. Effector and naturally occurring regulatory T cells display no abnormalities in activation induced cell death in NOD mice. PLoS One 2011; 6:e21630. [PMID: 21738739 PMCID: PMC3124542 DOI: 10.1371/journal.pone.0021630] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 06/03/2011] [Indexed: 12/23/2022] Open
Abstract
Background Disturbed peripheral negative regulation might contribute to evolution of autoimmune insulitis in type 1 diabetes. This study evaluates the sensitivity of naïve/effector (Teff) and regulatory T cells (Treg) to activation-induced cell death mediated by Fas cross-linking in NOD and wild-type mice. Principal Findings Both effector (CD25−, FoxP3−) and suppressor (CD25+, FoxP3+) CD4+ T cells are negatively regulated by Fas cross-linking in mixed splenocyte populations of NOD, wild type mice and FoxP3-GFP tranegenes. Proliferation rates and sensitivity to Fas cross-linking are dissociated in Treg cells: fast cycling induced by IL-2 and CD3/CD28 stimulation improve Treg resistance to Fas-ligand (FasL) in both strains. The effector and suppressor CD4+ subsets display balanced sensitivity to negative regulation under baseline conditions, IL-2 and CD3/CD28 stimulation, indicating that stimulation does not perturb immune homeostasis in NOD mice. Effective autocrine apoptosis of diabetogenic cells was evident from delayed onset and reduced incidence of adoptive disease transfer into NOD.SCID by CD4+CD25− T cells decorated with FasL protein. Treg resistant to Fas-mediated apoptosis retain suppressive activity in vitro. The only detectable differential response was reduced Teff proliferation and upregulation of CD25 following CD3-activation in NOD mice. Conclusion These data document negative regulation of effector and suppressor cells by Fas cross-linking and dissociation between sensitivity to apoptosis and proliferation in stimulated Treg. There is no evidence that perturbed AICD in NOD mice initiates or promotes autoimmune insulitis.
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Affiliation(s)
- Ayelet Kaminitz
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
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Pandiyan P, Conti HR, Zheng L, Peterson AC, Mathern DR, Hernández-Santos N, Edgerton M, Gaffen SL, Lenardo MJ. CD4(+)CD25(+)Foxp3(+) regulatory T cells promote Th17 cells in vitro and enhance host resistance in mouse Candida albicans Th17 cell infection model. Immunity 2011; 34:422-34. [PMID: 21435589 DOI: 10.1016/j.immuni.2011.03.002] [Citation(s) in RCA: 207] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/20/2011] [Accepted: 03/02/2011] [Indexed: 12/16/2022]
Abstract
Th17 cells and CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells are thought to promote and suppress inflammatory responses, respectively. Here we explore why under Th17 cell polarizing conditions, Treg cells did not suppress, but rather upregulated, the expression of interleukin-17A (IL-17A), IL-17F, and IL-22 from responding CD4(+) T cells (Tresp cells). Upregulation of IL-17 cytokines in Tresp cells was dependent on consumption of IL-2 by Treg cells, especially at early time points both in vitro and in vivo. During an oral Candida albicans infection in mice, Treg cells induced IL-17 cytokines in Tresp cells, which markedly enhanced fungal clearance and recovery from infection. These findings show how Treg cells can promote acute Th17 cell responses to suppress mucosal fungus infections and reveal that Treg cells have a powerful capability to fight infections besides their role in maintaining tolerance or immune homeostasis.
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Affiliation(s)
- Pushpa Pandiyan
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Berretta F, St-Pierre J, Piccirillo CA, Stevenson MM. IL-2 Contributes to Maintaining a Balance between CD4+Foxp3+ Regulatory T Cells and Effector CD4+ T Cells Required for Immune Control of Blood-Stage Malaria Infection. THE JOURNAL OF IMMUNOLOGY 2011; 186:4862-71. [DOI: 10.4049/jimmunol.1003777] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Chougnet CA, Tripathi P, Lages CS, Raynor J, Sholl A, Fink P, Plas DR, Hildeman DA. A major role for Bim in regulatory T cell homeostasis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:156-63. [PMID: 21098226 PMCID: PMC3066029 DOI: 10.4049/jimmunol.1001505] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We have previously shown that regulatory T cells (Treg) accumulate dramatically in aged animals and negatively impact the ability to control persistent infection. However, the mechanisms underlying the age-dependent accrual of Treg remain unclear. In this study, we show that Treg accumulation with age is progressive and likely not the result of increased thymic output, increased peripheral proliferation, or from enhanced peripheral conversion. Instead, we found that Treg from aged mice are more resistant to apoptosis than Treg from young mice. Although Treg from aged mice had increased expression of functional IL-7Rα, we found that IL-7R signaling was not required for maintenance of Treg in vivo. Notably, aged Treg exhibit decreased expression of the proapoptotic molecule Bim compared with Treg from young mice. Furthermore, in the absence of Bim, Treg accumulate rapidly, accounting for >25% of the CD4(+) T cell compartment by 6 mo of age. Additionally, accumulation of Treg in Bim-deficient mice occurred after the cells left the transitional recent thymic emigrant compartment. Mechanistically, we show that IL-2 drives preferential proliferation and accumulation of Bim(lo) Treg. Collectively, our data suggest that chronic stimulation by IL-2 leads to preferential expansion of Treg having low expression of Bim, which favors their survival and accumulation in aged hosts.
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Affiliation(s)
- Claire A Chougnet
- Division of Molecular Immunology, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA.
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Kaminitz A, Askenasy EM, Yaniv I, Stein J, Askenasy N. Apoptosis of purified CD4+ T cell subsets is dominated by cytokine deprivation and absence of other cells in new onset diabetic NOD mice. PLoS One 2010; 5:e15684. [PMID: 21209873 PMCID: PMC3013115 DOI: 10.1371/journal.pone.0015684] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 11/22/2010] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Regulatory T cells (Treg) play a significant role in immune homeostasis and self-tolerance. Excessive sensitivity of isolated Treg to apoptosis has been demonstrated in NOD mice and humans suffering of type 1 diabetes, suggesting a possible role in the immune dysfunction that underlies autoimmune insulitis. In this study the sensitivity to apoptosis was measured in T cells from new onset diabetic NOD females, comparing purified subsets to mixed cultures. PRINCIPAL FINDINGS Apoptotic cells are short lived in vivo and death occurs primarily during isolation, manipulation and culture. Excessive susceptibility of CD25(+) T cells to spontaneous apoptosis is characteristic of isolated subsets, however disappears when death is measured in mixed splenocyte cultures. In variance, CD25(-) T cells display balanced sensitivity to apoptosis under both conditions. The isolation procedure removes soluble factors, IL-2 playing a significant role in sustaining Treg viability. In addition, pro- and anti-apoptotic signals are transduced by cell-to-cell interactions: CD3 and CD28 protect CD25(+) T cells from apoptosis, and in parallel sensitize naïve effector cells to apoptosis. Treg viability is modulated both by other T cells and other subsets within mixed splenocyte cultures. Variations in sensitivity to apoptosis are often hindered by fast proliferation of viable cells, therefore cycling rates are mandatory to adequate interpretation of cell death assays. CONCLUSIONS The sensitivity of purified Treg to apoptosis is dominated by cytokine deprivation and absence of cell-to-cell interactions, and deviate significantly from measurements in mixed populations. Balanced sensitivity of naïve/effector and regulatory T cells to apoptosis in NOD mice argues against the concept that differential susceptibility affects disease evolution and progression.
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Affiliation(s)
- Ayelet Kaminitz
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Enosh M. Askenasy
- Soroka Medical School, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Isaac Yaniv
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Department of Pediatric Hematology-Oncology, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Jerry Stein
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Bone Marrow Transplant Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Nadir Askenasy
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- * E-mail:
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50
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Simonetta F, Chiali A, Cordier C, Urrutia A, Girault I, Bloquet S, Tanchot C, Bourgeois C. Increased CD127 expression on activated FOXP3+CD4+ regulatory T cells. Eur J Immunol 2010; 40:2528-38. [PMID: 20690182 DOI: 10.1002/eji.201040531] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Regulatory T cells (Treg) are commonly identified by CD25 (IL-2R alpha) surface expression and/or intracellular expression of the FOXP3 transcription factor. In addition, Treg are also characterized by low CD127 (IL-7R alpha) expression when compared to conventional T cells and their biology in the periphery is considered essentially independent of IL-7. We further investigated CD127 expression on Treg and we demonstrated differential CD127 expression depending on Treg subsets considered. Notably, we observed high CD127 expression on inducible costimulatory molecule (ICOS)- and CD103-expressing Treg subsets. Since these two markers reflect activation status, we addressed whether Treg activation modulated CD127 expression. We demonstrated that in contrast to conventional T cells, Treg significantly upregulated CD127 expression during in vitro and in vivo activation using adoptive transfer and contact dermatitis models. High CD127 expression on Treg was also predominantly detected ex vivo in some specific sites, notably bone marrow and skin. Importantly, higher CD127 expression on Treg correlated with higher phosphorylation of STAT5 upon IL-7 exposure. High CD127 expression on Treg also provided survival advantage upon in vitro incubation with IL-7. We thus demonstrated that low CD127 expression is not an intrinsic characteristic of Treg and we identified activated Treg as a potential target of endogenous or therapeutic IL-7.
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