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Nemoto S, Uchida K, Ohno H. Implications of Genetic Factors Underlying Mouse Hydronephrosis: Cautionary Considerations on Phenotypic Interpretation in Genetically Engineered Mice. Int J Mol Sci 2024; 25:7203. [PMID: 39000307 PMCID: PMC11241513 DOI: 10.3390/ijms25137203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 06/24/2024] [Accepted: 06/26/2024] [Indexed: 07/16/2024] Open
Abstract
Hydronephrosis, the dilation of kidneys due to abnormal urine retention, occurs spontaneously in certain inbred mouse strains. In humans, its occurrence is often attributed to acquired urinary tract obstructions in adults, whereas in children, it can be congenital. However, the genetic factors underlying hydronephrosis pathogenesis remain unclear. We investigated the cause of hydronephrosis by analyzing tetraspanin 7 (Tspan7) gene-modified mice, which had shown a high incidence of hydronephrosis-like symptoms. We found that these mice were characterized by low liver weights relative to kidney weights and elevated blood ammonia levels, suggesting liver involvement in hydronephrosis. Gene expression analysis of the liver suggested that dysfunction of ornithine transcarbamylase (OTC), encoded by the X chromosome gene Otc and involved in the urea cycle, may contribute as a congenital factor in hydronephrosis. This OTC dysfunction may be caused by genomic mutations in X chromosome genes contiguous to Otc, such as Tspan7, or via the genomic manipulations used to generate transgenic mice, including the introduction of Cre recombinase DNA cassettes and cleavage of loxP by Cre recombinase. Therefore, caution should be exercised in interpreting the hydronephrosis phenotype observed in transgenic mice as solely a physiological function of the target gene.
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Affiliation(s)
- Shino Nemoto
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Kazuyo Uchida
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Hiroshi Ohno
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
- Laboratory for Immune Regulation, Graduate School of Medical and Pharmaceutical Sciences, Chiba University, Chiba 260-0856, Japan
- Immunobiology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama 230-0045, Japan
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2
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Chamoto K, Yaguchi T, Tajima M, Honjo T. Insights from a 30-year journey: function, regulation and therapeutic modulation of PD1. Nat Rev Immunol 2023; 23:682-695. [PMID: 37185300 DOI: 10.1038/s41577-023-00867-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2023] [Indexed: 05/17/2023]
Abstract
PD1 was originally discovered in 1992 as a molecule associated with activation-induced cell death in T cells. Over the past 30 years, it was found that PD1 has a critical role in avoiding overactivation-induced cell death and autoimmunity, whereas its inhibition unleashes anticancer immunity. Here, we outline the journey from the discovery of PD1 to its role as a breakthrough target in cancer immunotherapy. We describe its regulation and function and examine how a mechanistic understanding of PD1 signalling suggests a central function in setting the T cell activation threshold, thereby controlling T cell proliferation, differentiation, exhaustion and metabolic status. This threshold theory, in combination with new insights into T cell metabolism and a better understanding of immune cell modulation by the microbiota, can provide guidance for the development of efficient combination therapies. Moreover, we discuss the mechanisms underlying immune-related adverse events after PD1-targeted therapy and their possible treatment.
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Affiliation(s)
- Kenji Chamoto
- Division of Immunology and Genomic Medicine, Center for Cancer Immunotherapy and Immunobiology, Kyoto University Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Tomonori Yaguchi
- Division of Immunology and Genomic Medicine, Center for Cancer Immunotherapy and Immunobiology, Kyoto University Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Masaki Tajima
- Division of Integrated High-Order Regulatory Systems, Center for Cancer Immunotherapy and Immunobiology, Kyoto University Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Tasuku Honjo
- Division of Immunology and Genomic Medicine, Center for Cancer Immunotherapy and Immunobiology, Kyoto University Graduate School of Medicine, Kyoto University, Kyoto, Japan.
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3
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Sugiura D, Okazaki IM, Maeda TK, Maruhashi T, Shimizu K, Arakaki R, Takemoto T, Ishimaru N, Okazaki T. PD-1 agonism by anti-CD80 inhibits T cell activation and alleviates autoimmunity. Nat Immunol 2022; 23:399-410. [PMID: 35145298 DOI: 10.1038/s41590-021-01125-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 12/20/2021] [Indexed: 12/11/2022]
Abstract
Targeted blockade of the checkpoint molecule programmed cell death 1 (PD-1) can activate tumor-specific T cells to destroy tumors, whereas targeted potentiation of PD-1 is expected to suppress autoreactive T cells and alleviate autoimmune diseases. However, the development of methods to potentiate PD-1 remains challenging. Here we succeeded in eliciting PD-1 function by targeting the cis-PD-L1-CD80 duplex, formed by binding of CD80 to the PD-1 ligand PD-L1, that attenuates PD-L1-PD-1 binding and abrogates PD-1 function. By generating anti-CD80 antibodies that detach CD80 from the cis-PD-L1-CD80 duplex and enable PD-L1 to engage PD-1 in the presence of CD80, we demonstrate that the targeted dissociation of cis-PD-L1-CD80 duplex elicits PD-1 function in the condition where PD-1 function is otherwise restricted. We demonstrate using murine models that the removal of PD-1 restriction is effective in alleviating autoimmune disease symptoms. Our findings establish a method to potentiate PD-1 function and propose the removal of restraining mechanisms as an efficient strategy to potentiate the function of inhibitory molecules.
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Affiliation(s)
- Daisuke Sugiura
- Laboratory of Molecular Immunology, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.,Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Il-Mi Okazaki
- Laboratory of Molecular Immunology, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.,Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Takeo K Maeda
- Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Takumi Maruhashi
- Laboratory of Molecular Immunology, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.,Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Kenji Shimizu
- Laboratory of Molecular Immunology, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.,Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Rieko Arakaki
- Department of Oral Molecular Pathology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Tatsuya Takemoto
- Laboratory for Embryology, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Naozumi Ishimaru
- Department of Oral Molecular Pathology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Taku Okazaki
- Laboratory of Molecular Immunology, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan. .,Laboratory for Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan.
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4
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The Price of Success: Immune-Related Adverse Events from Immunotherapy in Lung Cancer. Curr Oncol 2021; 28:4392-4407. [PMID: 34898551 PMCID: PMC8628657 DOI: 10.3390/curroncol28060373] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/19/2021] [Accepted: 10/31/2021] [Indexed: 12/19/2022] Open
Abstract
Cancer immunotherapy has the goal of enhancing a patient’s intrinsic immune processes in order to mount a successful immune response against tumor cells. Cancer cells actively employ tactics to evade, delay, alter, or attenuate the anti-tumor immune response. Immune checkpoint inhibitors (ICIs) modulate endogenous regulatory immune mechanisms to enhance immune system activation, and have become the mainstay of therapy in many cancer types. This activation occurs broadly and as a result, activation is supraphysiologic and relatively non-specific, which can lead to immune-related adverse events (irAEs), the frequency of which depends on the patient, the cancer type, and the specific ICI antibody. Careful assessment of patients for irAEs through history taking, physical exam, and routine laboratory assessments are key to identifying irAEs at early stages, when they can potentially be managed more easily and before progressing to higher grades or more serious effects. Generally, most patients with low grade irAEs are eligible for re-challenge with ICIs, and the use of corticosteroids to address an irAE is not associated with poorer patient outcomes. This paper reviews immune checkpoint inhibitors (ICIs) including their mechanisms of action, usage, associated irAEs, and their management.
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Abstract
Anti-PD-1 therapies can activate tumor-specific T cells to destroy tumors. However, whether and how T cells with different antigen specificity and affinity are differentially regulated by PD-1 remain vaguely understood. Upon antigen stimulation, a variety of genes is induced in T cells. Recently, we found that T cell receptor (TCR) signal strength required for the induction of genes varies across different genes and PD-1 preferentially inhibits the induction of genes that require stronger TCR signal. As each T cell has its own response characteristics, inducibility of genes likely differs across different T cells. Accordingly, the inhibitory effects of PD-1 are also expected to differ across different T cells. In the current study, we investigated whether and how factors that modulate T cell responsiveness to antigenic stimuli influence PD-1 function. By analyzing TCRs with different affinities to peptide-MHC complexes (pMHC) and pMHCs with different affinities to TCR, we demonstrated that PD-1 inhibits the expression of TCR-inducible genes efficiently when TCR:pMHC affinity is low. In contrast, affinities of peptides to MHC and MHC expression levels did not affect PD-1 sensitivity of TCR-inducible genes although they markedly altered the dose responsiveness of T cells by changing the efficiency of pMHC formation, suggesting that the strength of individual TCR signal is the key determinant of PD-1 sensitivity. Accordingly, we observed a preferential expansion of T cells with low-affinity to tumor-antigen in PD-1-deficient mice upon inoculation of tumor cells. These results demonstrate that PD-1 imposes qualitative control of T cell responses by preferentially suppressing low-affinity T cells.
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Kumar S, Sarthi P, Mani I, Ashraf MU, Kang MH, Kumar V, Bae YS. Epitranscriptomic Approach: To Improve the Efficacy of ICB Therapy by Co-Targeting Intracellular Checkpoint CISH. Cells 2021; 10:2250. [PMID: 34571899 PMCID: PMC8466810 DOI: 10.3390/cells10092250] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 02/07/2023] Open
Abstract
Cellular immunotherapy has recently emerged as a fourth pillar in cancer treatment co-joining surgery, chemotherapy and radiotherapy. Where, the discovery of immune checkpoint blockage or inhibition (ICB/ICI), anti-PD-1/PD-L1 and anti-CTLA4-based, therapy has revolutionized the class of cancer treatment at a different level. However, some cancer patients escape this immune surveillance mechanism and become resistant to ICB-therapy. Therefore, a more advanced or an alternative treatment is required urgently. Despite the functional importance of epitranscriptomics in diverse clinico-biological practices, its role in improving the efficacy of ICB therapeutics has been limited. Consequently, our study encapsulates the evidence, as a possible strategy, to improve the efficacy of ICB-therapy by co-targeting molecular checkpoints especially N6A-modification machineries which can be reformed into RNA modifying drugs (RMD). Here, we have explained the mechanism of individual RNA-modifiers (editor/writer, eraser/remover, and effector/reader) in overcoming the issues associated with high-dose antibody toxicities and drug-resistance. Moreover, we have shed light on the importance of suppressor of cytokine signaling (SOCS/CISH) and microRNAs in improving the efficacy of ICB-therapy, with brief insight on the current monoclonal antibodies undergoing clinical trials or already approved against several solid tumor and metastatic cancers. We anticipate our investigation will encourage researchers and clinicians to further strengthen the efficacy of ICB-therapeutics by considering the importance of epitranscriptomics as a personalized medicine.
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Affiliation(s)
- Sunil Kumar
- Department of Biological Sciences, Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea; (M.U.A.); (M.-H.K.)
- Science Research Center (SRC) for Immune Research on Non-lymphoid Organ (CIRNO), Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea
| | - Parth Sarthi
- University Department of Botany, M.Sc. Biotechnology, Ranchi University, Ranchi 834008, India;
| | - Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi 110049, India;
| | - Muhammad Umer Ashraf
- Department of Biological Sciences, Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea; (M.U.A.); (M.-H.K.)
- Science Research Center (SRC) for Immune Research on Non-lymphoid Organ (CIRNO), Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea
| | - Myeong-Ho Kang
- Department of Biological Sciences, Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea; (M.U.A.); (M.-H.K.)
- Science Research Center (SRC) for Immune Research on Non-lymphoid Organ (CIRNO), Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea
| | - Vishal Kumar
- Department of Pharmaceutical Science, Dayananda Sagar University, Bengaluru 560078, India;
| | - Yong-Soo Bae
- Department of Biological Sciences, Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea; (M.U.A.); (M.-H.K.)
- Science Research Center (SRC) for Immune Research on Non-lymphoid Organ (CIRNO), Sungkyunkwan University, Jangan-gu, Suwon 16419, Gyeonggi-do, Korea
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Nandi D, Pathak S, Verma T, Singh M, Chattopadhyay A, Thakur S, Raghavan A, Gokhroo A, Vijayamahantesh. T cell costimulation, checkpoint inhibitors and anti-tumor therapy. J Biosci 2021. [PMID: 32345776 DOI: 10.1007/s12038-020-0020-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The hallmarks of the adaptive immune response are specificity and memory. The cellular response is mediated by T cells which express cell surface T cell receptors (TCRs) that recognize peptide antigens in complex with major histocompatibility complex (MHC) molecules on antigen presenting cells (APCs). However, binding of cognate TCRs with MHC-peptide complexes alone (signal 1) does not trigger optimal T cell activation. In addition to signal 1, the binding of positive and negative costimulatory receptors to their ligands modulates T cell activation. This complex signaling network prevents aberrant activation of T cells. CD28 is the main positive costimulatory receptor on naı¨ve T cells; upon activation, CTLA4 is induced but reduces T cell activation. Further studies led to the identification of additional negative costimulatory receptors known as checkpoints, e.g. PD1. This review chronicles the basic studies in T cell costimulation that led to the discovery of checkpoint inhibitors, i.e. antibodies to negative costimulatory receptors (e.g. CTLA4 and PD1) which reduce tumor growth. This discovery has been recognized with the award of the 2018 Nobel prize in Physiology/Medicine. This review highlights the structural and functional roles of costimulatory receptors, the mechanisms by which checkpoint inhibitors work, the challenges encountered and future prospects.
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Affiliation(s)
- Dipankar Nandi
- Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, India
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8
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Wing JB, Lim EL, Sakaguchi S. Control of foreign Ag-specific Ab responses by Treg and Tfr. Immunol Rev 2020; 296:104-119. [PMID: 32564426 DOI: 10.1111/imr.12888] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/11/2020] [Accepted: 05/21/2020] [Indexed: 12/15/2022]
Abstract
Regulatory T cells (Tregs) expressing the transcription factor Foxp3 play a critical role in the control of immune homeostasis including the regulation of humoral immunity. Recently, it has become clear that a specialized subset of Tregs, T-follicular regulatory cells (Tfr), have a particular role in the control of T-follicular helper (Tfh) cell-driven germinal center (GC) responses. Following similar differentiation signals as received by Tfh, Tfr gain expression of characteristic chemokine receptors and transcription factors such as CXCR5 and BCL6 allowing them to travel to the B-cell follicle and deliver in situ suppression. It seems clear that Tfr are critical for the prevention of autoimmune antibody induction. However, their role in the control of foreign antigen-specific antibody responses appears more complex with various reports demonstrating either increased or decreased antigen-specific antibody responses following inhibition of Tfr function. Due to their recent discovery, our understanding of Tfr formation and function still has many gaps. In this review, we discuss our current knowledge of both Tregs and Tfr in the context of humoral immunity and how these cells might be manipulated in order to better control vaccine responses.
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Affiliation(s)
- James B Wing
- Laboritory of Human Immunology (Single Cell Immunology), Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Ee Lyn Lim
- Laboratory of Experimental Immunology, Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Shimon Sakaguchi
- Laboratory of Experimental Immunology, Immunology Frontier Research Center, Osaka University, Suita, Japan.,Department of Experimental Pathology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
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9
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Ramos-Casals M, Brahmer JR, Callahan MK, Flores-Chávez A, Keegan N, Khamashta MA, Lambotte O, Mariette X, Prat A, Suárez-Almazor ME. Immune-related adverse events of checkpoint inhibitors. Nat Rev Dis Primers 2020; 6:38. [PMID: 32382051 PMCID: PMC9728094 DOI: 10.1038/s41572-020-0160-6] [Citation(s) in RCA: 669] [Impact Index Per Article: 167.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/02/2020] [Indexed: 02/06/2023]
Abstract
Cancer immunotherapies have changed the landscape of cancer treatment during the past few decades. Among them, immune checkpoint inhibitors, which target PD-1, PD-L1 and CTLA-4, are increasingly used for certain cancers; however, this increased use has resulted in increased reports of immune-related adverse events (irAEs). These irAEs are unique and are different to those of traditional cancer therapies, and typically have a delayed onset and prolonged duration. IrAEs can involve any organ or system. These effects are frequently low grade and are treatable and reversible; however, some adverse effects can be severe and lead to permanent disorders. Management is primarily based on corticosteroids and other immunomodulatory agents, which should be prescribed carefully to reduce the potential of short-term and long-term complications. Thoughtful management of irAEs is important in optimizing quality of life and long-term outcomes.
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Affiliation(s)
- Manuel Ramos-Casals
- Department of Autoimmune Diseases, ICMiD, Barcelona, Spain. .,Laboratory of Autoimmune Diseases Josep Font, IDIBAPS-CELLEX, Barcelona, Spain. .,Department of Medicine, University of Barcelona, Hospital Clínic, Barcelona, Spain.
| | - Julie R. Brahmer
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD, USA
| | - Margaret K. Callahan
- Melanoma and Immunotherapeutics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA,Weill Cornell Medical College, New York, NY, USA,Parker Institute for Cancer Immunotherapy, Memorial Sloan Kettering Cancer Center, New York, NY
| | | | - Niamh Keegan
- Melanoma and Immunotherapeutics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA,Weill Cornell Medical College, New York, NY, USA
| | - Munther A. Khamashta
- Lupus Clinic, Rheumatology Department, Dubai Hospital, Dubai, United Arab Emirates
| | - Olivier Lambotte
- APHP Médecine Interne/Immunologie Clinique, Hôpital Bicêtre, Paris, France,Université Paris-Saclay – INSERM U1184 - CEA, Immunology of Viral Infections and Autoimmune Diseases, IDMIT Department, IBFJ, Fontenay-aux-Roses and Le Kremlin-Bicêtre, France
| | - Xavier Mariette
- Université Paris-Saclay, INSERM, CEA, Centre de recherche en Immunologie des infections virales et des maladies auto-immunes ; AP-HP.Université Paris-Saclay, Hôpital Bicêtre, Rheumatology Department, Le Kremlin Bicêtre, France
| | - Aleix Prat
- Translational Genomic and Targeted Therapeutics in Solid Tumors, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain,Department of Medical Oncology, Hospital Clínic of Barcelona, Barcelona, Spain
| | - Maria E. Suárez-Almazor
- Section of Rheumatology/Clinical Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Okazaki T, Okazaki IM. Stimulatory and Inhibitory Co-signals in Autoimmunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1189:213-232. [PMID: 31758536 DOI: 10.1007/978-981-32-9717-3_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Co-receptors cooperatively regulate the function of immune cells to optimize anti-infectious immunity while limiting autoimmunity by providing stimulatory and inhibitory co-signals. Among various co-receptors, those in the CD28/CTLA-4 family play fundamental roles in the regulation of lymphocytes by modulating the strength, quality, and/or duration of the antigen receptor signal. The development of the lethal lymphoproliferative disorder and various tissue-specific autoimmune diseases in mice deficient for CTLA-4 and PD-1, respectively, clearly demonstrates their pivotal roles in the development and the maintenance of immune tolerance. The recent success of immunotherapies targeting CTLA-4 and PD-1 in the treatment of various cancers highlights their critical roles in the regulation of cancer immunity in human. In addition, the development of multifarious autoimmune diseases as immune-related adverse events of anti-CTLA-4 and anti-PD-1/PD-L1 therapies and the successful clinical application of the CD28 blocking therapy using CTLA-4-Ig to the treatment of arthritis assure their crucial roles in the regulation of autoimmunity in human. Accumulating evidences in mice and humans indicate that genetic and environmental factors strikingly modify effects of the targeted inhibition and potentiation of co-signals. In this review, we summarize our current understanding of the roles of CD28, CTLA-4, and PD-1 in autoimmunity. Deeper understandings of the context-dependent and context-independent functions of co-signals are essential for the appropriate usage and the future development of innovative immunomodulatory therapies for a diverse array of diseases.
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Affiliation(s)
- Taku Okazaki
- Division of Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan.
| | - Il-Mi Okazaki
- Division of Immune Regulation, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
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11
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Friedrich SK, Lang PA, Friebus-Kardash J, Duhan V, Bezgovsek J, Lang KS. Mechanisms of lymphatic system-specific viral replication and its potential role in autoimmune disease. Clin Exp Immunol 2019; 195:64-73. [PMID: 30444956 DOI: 10.1111/cei.13241] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2018] [Indexed: 12/15/2022] Open
Abstract
Viral infections can be fatal because of the direct cytopathic effects of the virus or the induction of a strong, uncontrolled inflammatory response. Virus and host intrinsic characteristics strongly modulate the outcome of viral infections. Recently we determined the circumstances under which enhanced replication of virus within the lymphoid tissue is beneficial for the outcome of a disease. This enforced viral replication promotes anti-viral immune activation and, counterintuitively, accelerates virus control. In this review we summarize the mechanisms that contribute to enforced viral replication. Antigen-presenting cells and CD169+ macrophages exhibit enforced viral replication after infection with the model viruses lymphocytic choriomeningitis virus (LCMV) and vesicular stomatitis virus (VSV). Ubiquitin-specific peptidase 18 (Usp18), an endogenous type I interferon blocker in CD169+ macrophages, has been identified as a proviral gene, as are B cell activating factor (BAFF) and carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). Lymphotoxins (LT) strongly enhance viral replication in the spleen and lymph nodes. All these factors modulate splenic architecture and thereby promote the development of CD169+ macrophages. Tumor necrosis factor alpha (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cell signaling (NF-κB) have been found to promote the survival of infected CD169+ macrophages, thereby similarly promoting enforced viral replication. Association of autoimmune disease with infections is evident from (1) autoimmune phenomena described during a chronic virus infection; (2) onset of autoimmune disease simultaneous to viral infections; and (3) experimental evidence. Involvement of virus infection during onset of type I diabetes is strongly evident. Epstein-Bar virus (EBV) infection was discussed to be involved in the pathogenesis of systemic lupus erythematosus. In conclusion, several mechanisms promote viral replication in secondary lymphatic organs. Identifying such factors in humans is a challenge for future studies.
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Affiliation(s)
- S-K Friedrich
- University of Duisburg-Essen, Institute of Immunology, Medical Faculty, Essen, Germany
| | - P A Lang
- Heinrich-Heine-University, Insitute of Molecular Medicine II, Düsseldorf, Germany
| | - J Friebus-Kardash
- University of Duisburg-Essen, Institute of Immunology, Medical Faculty, Essen, Germany
| | - V Duhan
- University of Duisburg-Essen, Institute of Immunology, Medical Faculty, Essen, Germany
| | - J Bezgovsek
- University of Duisburg-Essen, Institute of Immunology, Medical Faculty, Essen, Germany
| | - K S Lang
- University of Duisburg-Essen, Institute of Immunology, Medical Faculty, Essen, Germany
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12
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Tseng CC, Lin YZ, Lin CH, Li RN, Tsai WC, Ou TT, Wu CC, Sung WY, Yen JH. Genetic and epigenetic alteration of the programmed cell death 1 in rheumatoid arthritis. Eur J Clin Invest 2019; 49:e13094. [PMID: 30810221 DOI: 10.1111/eci.13094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 02/10/2019] [Accepted: 02/24/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Rheumatoid arthritis (RA) is an autoimmune disease where both genetics and epigenetics are contributing factors. In order to discover genetic and epigenetic associations with RA and its phenotypes, we analysed RNA expression, DNA variations and DNA methylation of programmed cell death 1 (PDCD1) in a cohort of RA patients and healthy controls. METHODS RA patients (n = 206) and healthy controls (n = 234) were included for analysis of PDCD1 expression, PDCD1 polymorphisms and PDCD1 methylation. Differences in continuous variables between groups were compared by applying t tests. Associations between phenotypes and genotypes were evaluated with contingency tables. Sensitivity analyses were conducted to confirm the robustness of results, considering potential confounding factors and different treatment response definitions. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated. RESULTS Higher expression of PDCD1 was found in RA compared to controls (P < 0.001), with similar PDCD1 polymorphisms in RA and controls. rs36084323 decreased inadequate response to conventional synthetic disease-modifying antirheumatic drugs (OR = 0.37, 95% CI = 0.19-0.72, P = 0.003), and rs41386349 increased rheumatoid factor seropositivity (OR = 11.89, 95% CI = 1.57-89.87, P = 0.003). Sensitivity analysis adjusting for further potential confounders and using different treatment response definition indicated similar results. Additionally, DNA methylation change at regulatory region of PDCD1 was detected in RA (P = 0.036). CONCLUSION Altogether, this was the first study to suggest genetic and epigenetic changes of PDCD1 in RA subsets and RA. Independent prospective cohorts are awaited to address the implications of these genetic and epigenetic changes in disease pathogenesis and phenotypes of RA.
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Affiliation(s)
- Chia-Chun Tseng
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Internal Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan
| | - Yuan-Zhao Lin
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chia-Hui Lin
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ruei-Nian Li
- Department of Biomedical Science and Environmental Biology, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Wen-Chan Tsai
- Division of Rheumatology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Tsan-Teng Ou
- Division of Rheumatology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Cheng-Chin Wu
- Division of Rheumatology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Wan-Yu Sung
- Division of Rheumatology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Jeng-Hsien Yen
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Division of Rheumatology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.,Institute of Biomedical Science, National Sun Yat-Sen University, Kaohsiung, Taiwan
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13
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Balancing cancer immunotherapy and immune-related adverse events: The emerging role of regulatory T cells. J Autoimmun 2019; 104:102310. [PMID: 31421963 DOI: 10.1016/j.jaut.2019.102310] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 07/24/2019] [Indexed: 02/06/2023]
Abstract
Advances in our understanding οf tumor immunity have prompted a paradigm shift in oncology, with the emergence of immunotherapy, where therapeutic agents are used to target immune cells rather than cancer cells. A real breakthrough in the field of immunotherapy came with the use of immune checkpoint inhibitors (ICI), namely antagonistic antibodies that block key immune regulatory molecules (checkpoint molecules), such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed cell death protein (PD-1) and its ligand PD-L1, that under physiologic conditions suppress T cell effector function. However, despite the enormous success, a significant proportion of patients do not respond, while responses are frequently accompanied by life-threatening autoimmune related adverse events (irAEs). A major impediment in the effectiveness of ICI immunotherapy is the tumoral resistance, which is dependent on the immunosuppressive nature of tumor microenvironment (TME). Regulatory T cells (Tregs) are among the most abundant suppressive cells in the TME and their presence has been correlated with tumor progression, invasiveness as well as metastasis. Tregs are characterized by the expression of the transcription factor Foxp3 and various mechanisms ranging from cell-to-cell contact to secretion of inhibitory molecules have been implicated in their function. Notably, Tregs amply express most of the checkpoint molecules such as CTLA4, PD1 and LAG3 and therefore represent a direct target of ICI immunotherapy. Taking into consideration the critical role of Tregs in maintenance of immune homeostasis and avoidance of autoimmunity it is plausible that targeting of Tregs by ICI immunotherapy results in the development of irAEs. Since the use of ICI becomes common, and new immune checkpoint molecules are currently under clinical trials for the treatment of cancer, the occurrence of irAEs is expected to dramatically rise. Herein we review the current literature focusing on the role of Tregs in cancer evolution, ICI response and development of irAEs. Unraveling the complex mechanisms that hinder the tumor immune surveillance and in particular how ICI immunotherapy imprint on Treg activities to promote cancer regression while avoid development of irAEs, will empower the design of novel immunotherapeutic modalities in cancer with increased efficacy and diminished adverse events.
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Jain S, Chen F. Developmental pathology of congenital kidney and urinary tract anomalies. Clin Kidney J 2018; 12:382-399. [PMID: 31198539 PMCID: PMC6543978 DOI: 10.1093/ckj/sfy112] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Indexed: 12/18/2022] Open
Abstract
Congenital anomalies of the kidneys or lower urinary tract (CAKUT) are the most common causes of renal failure in children and account for 25% of end-stage renal disease in adults. The spectrum of anomalies includes renal agenesis; hypoplasia; dysplasia; supernumerary, ectopic or fused kidneys; duplication; ureteropelvic junction obstruction; primary megaureter or ureterovesical junction obstruction; vesicoureteral reflux; ureterocele; and posterior urethral valves. CAKUT originates from developmental defects and can occur in isolation or as part of other syndromes. In recent decades, along with better understanding of the pathological features of the human congenital urinary tract defects, researchers using animal models have provided valuable insights into the pathogenesis of these diseases. However, the genetic causes and etiology of many CAKUT cases remain unknown, presenting challenges in finding effective treatment. Here we provide an overview of the critical steps of normal development of the urinary system, followed by a description of the pathological features of major types of CAKUT with respect to developmental mechanisms of their etiology.
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Affiliation(s)
- Sanjay Jain
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Feng Chen
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, MO, USA
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15
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Freitas CMT, Johnson DK, Weber KS. T Cell Calcium Signaling Regulation by the Co-Receptor CD5. Int J Mol Sci 2018; 19:E1295. [PMID: 29701673 PMCID: PMC5983667 DOI: 10.3390/ijms19051295] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/19/2018] [Accepted: 04/24/2018] [Indexed: 12/21/2022] Open
Abstract
Calcium influx is critical for T cell effector function and fate. T cells are activated when T cell receptors (TCRs) engage peptides presented by antigen-presenting cells (APC), causing an increase of intracellular calcium (Ca2+) concentration. Co-receptors stabilize interactions between the TCR and its ligand, the peptide-major histocompatibility complex (pMHC), and enhance Ca2+ signaling and T cell activation. Conversely, some co-receptors can dampen Ca2+ signaling and inhibit T cell activation. Immune checkpoint therapies block inhibitory co-receptors, such as cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) and programmed death 1 (PD-1), to increase T cell Ca2+ signaling and promote T cell survival. Similar to CTLA-4 and PD-1, the co-receptor CD5 has been known to act as a negative regulator of T cell activation and to alter Ca2+ signaling and T cell function. Though much is known about the role of CD5 in B cells, recent research has expanded our understanding of CD5 function in T cells. Here we review these recent findings and discuss how our improved understanding of CD5 Ca2+ signaling regulation could be useful for basic and clinical research.
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Affiliation(s)
- Claudia M Tellez Freitas
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84604, USA.
| | - Deborah K Johnson
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84604, USA.
| | - K Scott Weber
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84604, USA.
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16
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Suarez-Almazor ME, Kim ST, Abdel-Wahab N, Diab A. Review: Immune-Related Adverse Events With Use of Checkpoint Inhibitors for Immunotherapy of Cancer. Arthritis Rheumatol 2017; 69:687-699. [PMID: 28085999 DOI: 10.1002/art.40043] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 01/10/2017] [Indexed: 12/16/2022]
Affiliation(s)
| | - Sang T Kim
- The University of Texas MD Anderson Cancer Center, Houston
| | - Noha Abdel-Wahab
- The University of Texas MD Anderson Cancer Center, Houston, and Assiut University Hospitals, Assiut, Egypt
| | - Adi Diab
- The University of Texas MD Anderson Cancer Center, Houston
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17
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Lim TS, Chew V, Sieow JL, Goh S, Yeong JPS, Soon AL, Ricciardi-Castagnoli P. PD-1 expression on dendritic cells suppresses CD8 + T cell function and antitumor immunity. Oncoimmunology 2015; 5:e1085146. [PMID: 27141339 DOI: 10.1080/2162402x.2015.1085146] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/31/2015] [Accepted: 08/14/2015] [Indexed: 12/31/2022] Open
Abstract
Programmed death one (PD-1) is a well-established co-inhibitory regulator that suppresses proliferation and cytokine production of T cells. Despite remarkable progress in delineating the functional roles of PD-1 on T lymphocytes, little is known about the regulatory role of PD-1 expressed on myeloid cells such as dendritic cells (DCs). Here, we show that CD8+ T cells can be more potently activated to secrete IL-2 and IFNγ by PD-1-deficient DCs compared to wild-type DCs. Adoptive transfer of PD-1-deficient DCs demonstrated their superior capabilities in inducing antigen-specific CD8+ T cell proliferation in vivo. In addition, we provide first evidence demonstrating the existence of peripheral blood DCs and CD11c+ tumor-infiltrating myeloid cells that co-express PD-1 in patients with hepatocellular carcinoma (HCC). The existence of PD-1-expressing HCC-infiltrating DCs (HIDCs) was further supported in a mouse model of HCC. Intratumoral transfer of PD-1-deficient DCs rendered recipient mice resistant to the growth of HCC by promoting tumor-infiltrating CD8+ effector T cells to secrete perforin and granzyme B. This novel finding provides a deeper understanding of the role of PD-1 in immune regulation and has significant implications for cancer immunotherapies targeting PD-1.
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Affiliation(s)
- Tong Seng Lim
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), 8A Biomedical Grove, IMMUNOS Building #4, BIOPOLIS, Singapore; A. Menarini Biomarkers Singapore Pte Ltd, 30 Pasir Panjang Road, #08-32, Mapletree Business City, Singapore
| | - Valerie Chew
- SingHealth Translational Immunology and Inflammation Center (STIIC), Duke-NUS Medical School, The Academia , 20 College Road, Discovery Tower Level 8 , Singapore
| | - Je Lin Sieow
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , 8A Biomedical Grove, IMMUNOS Building #4, BIOPOLIS , Singapore
| | - Siting Goh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , 8A Biomedical Grove, IMMUNOS Building #4, BIOPOLIS , Singapore
| | - Joe Poh-Sheng Yeong
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), 8A Biomedical Grove, IMMUNOS Building #4, BIOPOLIS, Singapore; Department of Pathology, Singapore General Hospital, 20 College Road, Academia, Diagnostics Tower, Singapore
| | - Ai Ling Soon
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , 8A Biomedical Grove, IMMUNOS Building #4, BIOPOLIS , Singapore
| | - Paola Ricciardi-Castagnoli
- Genomics, Genetics and Biology Innovation Pole (PoloGGB), Piazza Gambuli, Edificio D, 3° Piano, Perugia, Italy; A. Menarini Biomarkers Singapore Pte Ltd, 30 Pasir Panjang Road, #08-32, Mapletree Business City, Singapore
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18
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Abstract
Maintenance of peripheral tolerance is essential for homeostasis of the immune system. While central tolerance mechanisms result in deletion of the majority of self-reactive T cells, T lymphocytes specific for self-antigens also escape this process and circulate in the periphery. To control the development of autoimmunity, multiple mechanisms of peripheral tolerance have evolved, including T cell anergy, deletion, and suppression by regulatory T (Treg) cells. The pathway consisting of the programmed cell death 1 (PD-1) receptor (CD279) and its ligands PD-L1 (B7-H1, CD274) and PD-L2 (B7-DC; CD273) plays a vital role in the induction and maintenance of peripheral tolerance. This pathway also regulates the balance between stimulatory and inhibitory signals needed for effective immunity and maintenance of T cell homeostasis. In contrast to this important beneficial role in maintaining T cell homeostasis, PD-1 mediates potent inhibitory signals that prevent the expansion and function of T effector cells and have detrimental effects on antiviral and antitumor immunity. Despite the compelling studies on the significant functional role of PD-1 in mediating inhibition of activated T cells, little is known about how PD-1 blocks T cell activation. Here, we will provide a brief overview of the signaling events that are regulated by PD-1 triggering, and we will discuss their implications on cell intrinsic and extrinsic mechanisms that determine the fate and function of T effector cells.
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19
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Chang JH, Chung Y. Regulatory T cells in B cell follicles. Immune Netw 2014; 14:227-36. [PMID: 25360073 PMCID: PMC4212083 DOI: 10.4110/in.2014.14.5.227] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 09/05/2014] [Accepted: 09/12/2014] [Indexed: 01/08/2023] Open
Abstract
Understanding germinal center reactions is crucial not only for the design of effective vaccines against infectious agents and malignant cells but also for the development of therapeutic intervention for the treatment of antibody-mediated immune disorders. Recent advances in this field have revealed specialized subsets of T cells necessary for the control of B cell responses in the follicle. These cells include follicular regulatory T cells and Qa-1-restricted cluster of differentiation (CD)8+ regulatory T cells. In this review, we discuss the current knowledge related to the role of regulatory T cells in the B cell follicle.
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Affiliation(s)
- Jae-Hoon Chang
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Korea
| | - Yeonseok Chung
- College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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20
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Springer DA, Allen M, Hoffman V, Brinster L, Starost MF, Bryant M, Eckhaus M. Investigation and identification of etiologies involved in the development of acquired hydronephrosis in aged laboratory mice with the use of high-frequency ultrasound imaging. PATHOBIOLOGY OF AGING & AGE RELATED DISEASES 2014; 4:24932. [PMID: 25143818 PMCID: PMC4119937 DOI: 10.3402/pba.v4.24932] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 06/16/2014] [Indexed: 11/14/2022]
Abstract
Laboratory mice develop naturally occurring lesions that affect biomedical research. Hydronephrosis is a recognized pathologic abnormality of the mouse kidney. Acquired hydronephrosis can affect any mouse, as it is caused by any naturally occurring disease that impairs free urine flow. Many etiologies leading to this condition are of particular significance to aging mice. Non-invasive ultrasound imaging detects renal pelvic dilation, renal enlargement, and parenchymal loss for pre-mortem identification of this condition. High-frequency ultrasound transducers produce high-resolution images of small structures, ideal for detecting organ pathology in mice. Using a 40 MHz linear array transducer, we obtained high-resolution images of a diversity of pathologic lesions occurring within the abdomen of seven geriatric mice with acquired hydronephrosis that enabled a determination of the underlying etiology. Etiologies diagnosed from the imaging results include pyelonephritis, neoplasia, urolithiasis, mouse urologic syndrome, and spontaneous hydronephrosis, and were confirmed at necropsy. A retrospective review of abdominal scans from an additional 149 aging mice shows that the most common etiologies associated with acquired hydronephrosis are mouse urologic syndrome and abdominal neoplasia. This report highlights the utility of high-frequency ultrasound for surveying research mice for age-related pathology, and is the first comprehensive report of multiple cases of acquired hydronephrosis in mice.
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Affiliation(s)
- Danielle A. Springer
- Murine Phenotyping Core, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Michele Allen
- Murine Phenotyping Core, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Victoria Hoffman
- Office of Research Services, Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Lauren Brinster
- Office of Research Services, Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Matthew F. Starost
- Office of Research Services, Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Mark Bryant
- Office of Research Services, Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Michael Eckhaus
- Office of Research Services, Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
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21
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A rheostat for immune responses: the unique properties of PD-1 and their advantages for clinical application. Nat Immunol 2014; 14:1212-8. [PMID: 24240160 DOI: 10.1038/ni.2762] [Citation(s) in RCA: 682] [Impact Index Per Article: 68.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 10/09/2013] [Indexed: 02/08/2023]
Abstract
PD-1, a negative coreceptor expressed on antigen-stimulated T cells and B cells, seems to serve as a 'rheostat' of the immune response. The molecular mechanisms of the functions of PD-1, in conjunction with the mild, chronic and strain-specific autoimmune phenotypes of PD-1-deficient mice, in contrast to the devastating fatal autoimmune disease of mice deficient in the immunomodulatory receptor CTLA-4, suggest that immunoregulation by PD-1 is rather antigen specific and is mainly cell intrinsic. Such unique properties make PD-1 a powerful target for immunological therapy, with highly effective clinical applications for cancer treatment.
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22
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Lehmann B, Schwab I, Böhm S, Lux A, Biburger M, Nimmerjahn F. FcγRIIB: a modulator of cell activation and humoral tolerance. Expert Rev Clin Immunol 2014; 8:243-54. [DOI: 10.1586/eci.12.5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Abstract
T(reg) cells are essential for the maintenance of immune homeostasis and prevention of autoimmunity. In humoral immune responses, loss of T(reg) cell function causes increased levels of serum autoantibodies, hyper-IgE, spontaneous generation of germinal centres, and enhanced numbers of specialised T follicular helper cells (T(fh) cells) controlled by the lineage-defining transcription factor BCL-6 (B-cell lymphoma 6). Recent studies have demonstrated that a subset of T(reg) cells [T follicular regulatory (T(freg)) cells] are able to co-opt the follicular T-cell program by gaining expression of BCL-6 and travelling to the follicle where they have an important role in the control of expansion of T(fh) cells and the germinal centre reaction. However, the mechanisms by which they exert this control are still under investigation. In this review, we discuss the effects of T(reg) cells on humoral immunity and the mechanisms by which they exert their regulatory function.
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Affiliation(s)
- James B Wing
- Department of Experimental Immunology, WPI Immunology Frontier Research Center, Osaka University, Suita 565-0871, Osaka, Japan
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24
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Nishiura H, Iwamoto S, Kido M, Aoki N, Maruoka R, Ikeda A, Chiba T, Watanabe N. Interleukin-21 and tumor necrosis factor-α are critical for the development of autoimmune gastritis in mice. J Gastroenterol Hepatol 2013; 28:982-91. [PMID: 23425147 DOI: 10.1111/jgh.12144] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/29/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIM Autoimmune gastritis (AIG), an organ-specific autoimmune disease, is accompanied by achlorhydria, pernicious anemia, gastric carcinoid tumors, and gastric cancer. Patients with AIG initially respond to corticosteroids but have a great potential to relapse after treatment is withdrawn. This study examines the roles of cytokines in order to identify potential therapeutic options for AIG patients. METHODS Using a mouse model of AIG, we monitored disease progression and administered antibodies in vivo to block cytokines. RESULTS We developed a mouse model of AIG with early onset and rapid progression in which neonatal thymectomy (NTx) was performed on programmed cell death 1-deficient (PD-1(-/-) ) mice on the BALB/c background. Using NTx-PD-1(-/-) mice, we found that in AIG lesions, interferon-γ, and tumor necrosis factor (TNF)-α together with interleukin-21 (IL-21) were highly expressed in the inflamed gastric mucosa. In addition, as with the injection of dexamethasone, in vivo administration of either anti-TNF-α or anti-IL-21 suppressed the development of AIG in NTx-PD-1(-/-) mice. CONCLUSIONS These data reveal the essential role of IL-21 in the development of AIG and suggest that in addition to corticosteroids, anti-TNF-α as well as anti-IL-21 have the potential to induce the remission of AIG, offering additional therapeutic options for AIG patients.
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Affiliation(s)
- Hisayo Nishiura
- Department of Gastroenterology and Hepatology, Kyoto University, Sakyo-ku, Kyoto, Japan
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25
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BALB/c-Fcgr2bPdcd1 mouse expressing anti-urothelial antibody is a novel model of autoimmune cystitis. Sci Rep 2012; 2:317. [PMID: 22432050 PMCID: PMC3307042 DOI: 10.1038/srep00317] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 02/23/2012] [Indexed: 01/22/2023] Open
Abstract
We report the impact of anti-urothelial autoantibody (AUAb) on urinary bladder phenotype in BALB/c mice deficient of the FcγRIIb and PD-1. AUAb was present in serum samples from approximately half of the double-knockout (DKO) mice, as detected by immunofluorescence and immunoblots for urothelial proteins including uroplakin IIIa. The AUAb-positive DKO mice showed degeneration of urothelial plaque and umbrella cells, along with infiltration of inflammatory cells in the suburothelial layer. TNFα and IL-1β were upregulated in the bladder and the urine of AUAb-positive DKO mice. Voiding behavior of mice was analyzed by the Voided Stain on Paper method. 10-week-old and older AUAb-positive DKO mice voided significantly less urine per void than did wild type (WT) mice. Furthermore, administration of the AUAb-containing serum to WT mice significantly reduced their urine volume per void. In summary, this report presents a novel comprehensive mouse model of autoimmune cystitis.
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26
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Nishiura H, Kido M, Aoki N, Iwamoto S, Maruoka R, Ikeda A, Chiba T, Ziegler SF, Watanabe N. Increased Susceptibility to Autoimmune Gastritis in Thymic Stromal Lymphopoietin Receptor-Deficient Mice. THE JOURNAL OF IMMUNOLOGY 2011; 188:190-7. [DOI: 10.4049/jimmunol.1003787] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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27
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Fcγ receptor IIB (FcγRIIB) maintains humoral tolerance in the human immune system in vivo. Proc Natl Acad Sci U S A 2011; 108:18772-7. [PMID: 22065769 DOI: 10.1073/pnas.1111810108] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Maintenance of immunological tolerance is crucial to prevent development of autoimmune disease. The production of autoantibodies is a hallmark of many autoimmune diseases and studies in mouse model systems suggest that inhibitory signaling molecules may be important checkpoints of humoral tolerance. By generating humanized mice with normal and functionally impaired Fcγ receptor IIB (FcγRIIB) variants, we show that the inhibitory Fcγ-receptor is a checkpoint of humoral tolerance in the human immune system in vivo. Impaired human FcγRIIB function resulted in the generation of higher levels of serum immunoglobulins, the production of different autoantibody specificities, and a higher proportion of human plasmablasts and plasma cells in vivo. Our results suggest that the inhibitory FcγRIIB may be an important checkpoint of humoral tolerance in the human immune system.
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Okazaki T, Okazaki IM, Wang J, Sugiura D, Nakaki F, Yoshida T, Kato Y, Fagarasan S, Muramatsu M, Eto T, Hioki K, Honjo T. PD-1 and LAG-3 inhibitory co-receptors act synergistically to prevent autoimmunity in mice. ACTA ACUST UNITED AC 2011; 208:395-407. [PMID: 21300912 PMCID: PMC3039848 DOI: 10.1084/jem.20100466] [Citation(s) in RCA: 231] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A new mouse model of spontaneous autoimmune disease reveals an important role for the inhibitory co-receptor LAG-3 in suppressing autoimmunity. Stimulatory and inhibitory co-receptors play fundamental roles in the regulation of the immune system. We describe a new mouse model of spontaneous autoimmune disease. Activation-induced cytidine deaminase–linked autoimmunity (aida) mice harbor a loss-of-function mutation in the gene encoding lymphocyte activation gene 3 (LAG-3), an inhibitory co-receptor. Although LAG-3 deficiency alone did not induce autoimmunity in nonautoimmune-prone mouse strains, it induced lethal myocarditis in BALB/c mice deficient for the gene encoding the inhibitory co-receptor programmed cell death 1 (PD-1). In addition, LAG-3 deficiency alone accelerated type 1 diabetes mellitus in nonobese diabetic mice. These results demonstrate that LAG-3 acts synergistically with PD-1 and/or other immunoregulatory genes to prevent autoimmunity in mice.
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Affiliation(s)
- Taku Okazaki
- Division of Immune Regulation, Institute for Genome Research, University of Tokushima, Kuramoto, Tokushima, Japan.
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Wang J, Okazaki IM, Yoshida T, Chikuma S, Kato Y, Nakaki F, Hiai H, Honjo T, Okazaki T. PD-1 deficiency results in the development of fatal myocarditis in MRL mice. Int Immunol 2010; 22:443-52. [PMID: 20410257 DOI: 10.1093/intimm/dxq026] [Citation(s) in RCA: 184] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The deficiency of programmed cell death 1 (PD-1, Pdcd1), a negative immuno-receptor belonging to the CD28/cytotoxic T lymphocyte antigen 4 (CTLA-4) family, can support various tissue-specific autoimmune conditions. Here, we analyzed the effect of PD-1 deficiency in MRL mice that is genetically predisposed to systemic autoimmunity. MRL-Pdcd1(-)(/-) mice developed a fatal myocarditis, which is reminiscent of CTLA-4-deficient (Ctla4(-)(/-)) mice. Massive infiltration of CD4(+) and CD8(+) T cells and myeloid cells was found in hearts of MRL-Pdcd1(-)(/-) mice concomitant with the production of high-titer auto-antibodies against cardiac myosin. In contrast to Ctla4(-)(/-) mice in which most of the CD4(+) T cells are non-specifically activated and invade various organs, T cells in the heart but not in the spleen and lymph nodes are activated in MRL-Pdcd1(-)(/-) mice, suggesting that myocarditis is mediated by antigen-specific autoimmune response. Heart infiltrating myeloid cells strongly suppressed the allogenic response of T cells in vitro, suggesting that these Mac1(+)Gr1(+) myeloid cells are phenotypically similar to myeloid suppressor cells, which can be found in tumor-bearing hosts. These findings unravel the hidden heart-specific autoimmune predisposition of MRL mice and provide MRL-Pdcd1(-)(/-) mice as a useful animal model of lymphocytic myocarditis.
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Affiliation(s)
- Jian Wang
- Department of Immunology and Genomic Medicine, Kyoto University, Yoshida-Konoe, Sakyo-ku, Japan
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31
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Chen F. Genetic and developmental basis for urinary tract obstruction. Pediatr Nephrol 2009; 24:1621-32. [PMID: 19085015 PMCID: PMC2844875 DOI: 10.1007/s00467-008-1072-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 11/15/2008] [Accepted: 11/18/2008] [Indexed: 12/31/2022]
Abstract
Urinary tract obstruction results in obstructive nephropathy and uropathy. It is the most frequent cause of renal failure in infants and children. In the past two decades studies of transgenic models and humans have greatly enhanced our understanding of the genetic factors and developmental processes important in urinary tract obstruction. The emerging picture is that development of the urinary tract requires precise integration of a variety of progenitor cell populations of different embryonic origins. Such integration is controlled by an intricate signaling network that undergoes dynamic changes as the embryo develops. Most congenital forms of urinary tract obstruction result from the disruption of diverse factors and genetic pathways involved in these processes, especially in the morphogenesis of the urinary conduit or the functional aspects of the pyeloureteral peristaltic machinery.
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Affiliation(s)
- Feng Chen
- Renal Division, Department of Internal Medicine, Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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PD-1 deficiency reveals various tissue-specific autoimmunity by H-2b and dose-dependent requirement of H-2g7 for diabetes in NOD mice. Proc Natl Acad Sci U S A 2008; 105:3533-8. [PMID: 18299579 DOI: 10.1073/pnas.0710951105] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Although many autoimmune diseases are associated with particular HLA/H-2 haplotypes, the mechanisms through which specific HLA/H-2 haplotypes afford autoimmune susceptibility remain enigmatic. Here, we analyzed the effects of the diabetes-associated (H-2(g7)) and an antidiabetogenic (H-2(b)) H-2 haplotypes in NOD mice deficient for programmed cell death-1 (PD-1, Pdcd1), a unique model of type 1 diabetes that confers complete penetrance and rapid onset of the disease. NOD-H2(b/b)Pdcd1(-/-) mice were completely protected from diabetes, confirming that H-2(g7) is indispensable for diabetes even in the absence of PD-1. However, NOD-H2(b/b)Pdcd1(-/-) mice developed autoimmune inflammation in multiple tissues including peripheral nerves, stomachs, and exocrine tissues, demonstrating that autoreactive T cells are generated in the context of H-2(b). These autoreactive T cells damaged target tissues only in the absence of PD-1, confirming that PD-1 deficiency unravels the hidden autoimmune susceptibility of the strain by reducing the threshold of T cell activation. Transfer experiments revealed that CD4 T cells are the effector cells of neuritis, and nerve-infiltrating CD4 T cells are strongly deviated toward Th1. Interestingly, neuritogenic T cells were also generated in the context of H-2(g7), in sharp contrast to the strict requirement of H-2(g7) for diabetes. In addition, 60% of the NOD-H2(b/g7)Pdcd1(-/-) mice developed diabetes, suggesting that H-2(b) does not dominantly suppress diabetes and that H-2(g7) induces diabetes in a dose-dependent fashion.
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Abstract
Receptors for immunoglobulins [Fc-receptors (FcRs)] are widely expressed throughout the immune system. By binding to the antibody Fc-portion, they provide a link between the specificity of the adaptive immune system and the powerful effector functions triggered by innate immune effector cells. By virtue of coexpression of activating and inhibitory FcRs on the same cell, they set a threshold for immune cell activation by immune complexes (ICs). Besides their involvement in the efferent phase of an immune response, they are also important for modulating adaptive immune responses by regulating B cell and dendritic cell (DC) activation. Deletion of the inhibitory FcR leads to the loss of tolerance in the humoral immune system and the development of autoimmune disease. Uptake of ICs by FcRs on DCs and the concommitant triggering of activating and inhibitory signaling pathways will determine the strength of the initiated T-cell response. Loss of this balanced signaling results in uncontrolled responses that can lead to the damage of healthy tissues and ultimately to the initiation of autoimmune processes. In this chapter, we will discuss how coexpression of different activating and inhibitory receptors on different immune cells of the innate and adaptive immune system modulates cell activity. Moreover, we will focus on exogenous factors that can influence the balanced triggering of activating and inhibitory FcRs, such as the cytokine milieu and the role of differential antibody glycosylation.
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Tarasenko T, Dean JA, Bolland S. FcgammaRIIB as a modulator of autoimmune disease susceptibility. Autoimmunity 2007; 40:409-17. [PMID: 17729034 DOI: 10.1080/08916930701464665] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Antibodies are secreted to recognize and in some cases directly neutralize pathogens. Another important means by which they are essential components of the immune system is through binding to Fc receptors. Effector responses triggered by antibody binding of Fc receptors affect a host of important cellular responses such as phagocytosis, inflammatory cytokine release, antigen presentation, and regulation of humoral responses. A crucial check on this antibody-mediated signal is through the inhibitory receptor, FcgammaRIIB. In this review we discuss how dysregulation of FcgammaRIIB can result in a lowered threshold for autoimmunity in mice and humans. We close with a discussion of the potential for applying these findings to immunotherapy.
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Affiliation(s)
- Tatyana Tarasenko
- Autoimmunity and Functional Genomics Section, Laboratory of Immunogenetics, Rockville, MD 20852, USA
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Zeng Y, Wu XX, Homma Y, Yoshimura N, Iwaki H, Kageyama S, Yoshiki T, Kakehi Y. Uroplakin III-delta4 messenger RNA as a promising marker to identify nonulcerative interstitial cystitis. J Urol 2007; 178:1322-7; discussion 1327. [PMID: 17698128 DOI: 10.1016/j.juro.2007.05.125] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE Interstitial cystitis remains a poorly understood urological condition characterized by chronic pelvic pain and increased urinary frequency in the absence of any known etiology. Urothelial dysfunction and other abnormalities are presumed to be involved in the disease. Uroplakins that are expressed by urothelial cells are thought to have an important role as major barrier proteins on the apical surface of the urothelium. MATERIALS AND METHODS Gene expression of uroplakin Ia, Ib, II, III and III-delta4 was quantitatively measured in bladder biopsy samples from 29 patients with interstitial cystitis and 16 control subjects using real-time reverse transcriptase-polymerase chain reaction. RESULTS The mRNA levels of the uroplakin Ia, Ib and II genes were relatively low and uroplakin III was relatively high in interstitial cystitis bladders compared to normal controls, although not significantly. Uroplakin III-delta4, a splicing variant of uroplakin III, was significantly up-regulated in interstitial cystitis samples (p <0.001). When patients with interstitial cystitis were divided into those with and without ulcerative changes, the uroplakin III and III-delta4 genes were significantly up-regulated only in patients with nonulcerative interstitial cystitis. Even more interesting was the finding that up-regulation of uroplakin III-delta4 was much more prominent than that of uroplakin III, that is 26.5 vs 5.6-fold compared to the median values of normal subjects. CONCLUSIONS Although the clinical implications of the over expression of uroplakin III and III-delta4 in nonulcerative interstitial cystitis bladders remains to be clarified, from the diagnostic viewpoint uroplakin III-delta4 is a potential marker for identifying nonulcerative interstitial cystitis.
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Affiliation(s)
- Yu Zeng
- Department of Urology, Kagawa University Faculty of Medicine, Kagawa, Japan
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Jenkins D, Woolf AS. Uroplakins: new molecular players in the biology of urinary tract malformations. Kidney Int 2006; 71:195-200. [PMID: 17183244 DOI: 10.1038/sj.ki.5002053] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The uroplakins (UPs) are a family of proteins which associate with each other and form plaques on the apical surface of the urothelium. These plaques contribute to a permeability barrier, preventing the influx of urine from the urinary tract lumen. Urinary tract malformations associated with human and mouse UP mutations, the human fetal expression patterns of UPs and experiments in Xenopus oocytes are collectively revealing new functions for the UPs, forcing us to view these proteins in a new light. Rather than simply being products of the urothelial differentiation program, they may be a group of proteins central to the process of urinary tract differentiation itself.
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Affiliation(s)
- D Jenkins
- Clinical Genetics Unit, Weatherall Institute of Molecular Medicine, University of Oxford, UK
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Nimmerjahn F. Activating and inhibitory FcγRs in autoimmune disorders. ACTA ACUST UNITED AC 2006; 28:305-19. [PMID: 17115158 DOI: 10.1007/s00281-006-0052-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2006] [Accepted: 09/29/2006] [Indexed: 10/24/2022]
Abstract
Autoimmune disorders are characterized by the destruction of self-tissues by the immune system. Multiple checkpoints are in place to prevent autoreactivity under normal circumstances. Coexpression of activating and inhibitory Fc receptors (FcR) represents such a checkpoint by establishing a threshold for immune cell activation. In many human autoimmune diseases, however, balanced FcR expression is disturbed. Analysis of murine model systems provides strong evidence that aberrant FcR expression can result in uncontrolled immune responses and the initiation of autoimmune disease. This review will summarize this data and explain how this information might be used to better understand human autoimmune diseases and to develop novel therapeutic strategies.
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Affiliation(s)
- Falk Nimmerjahn
- Laboratory of Molecular Genetics and Immunology, 1230 York Avenue, New York, NY, 10021, USA,
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Okazaki T, Honjo T. The PD-1-PD-L pathway in immunological tolerance. Trends Immunol 2006; 27:195-201. [PMID: 16500147 DOI: 10.1016/j.it.2006.02.001] [Citation(s) in RCA: 536] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 12/22/2005] [Accepted: 02/08/2006] [Indexed: 12/12/2022]
Abstract
Since the first observation of spontaneous autoimmune diseases in programmed cell death 1 (PD-1) knockout mice, PD-1 has been postulated to have essential roles in the regulation of autoimmunity but the precise mechanism was largely unknown. Recent studies clearly demonstrated that PD-1 has dual roles in immunological tolerance: induction and maintenance of peripheral tolerance. PD-1 ligands (PD-Ls) on antigen-presenting cells have been shown to switch off autoreactive T cells and induce peripheral tolerance, whereas those on parenchymal cells prevent tissue destruction by suppressing effector T cells to maintain tolerance. In addition, PD-1 and other immuno-inhibitory receptors have been shown to collaborate in the regulation of tolerance. Here, we review recent studies on the role of PD-1 in immunological tolerance and discuss possible clinical applications of PD-1 manipulation.
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Affiliation(s)
- Taku Okazaki
- 21st Century Center of Excellence Program, Graduate School of Medicine, Kyoto University, Yoshida-Konoe, Sakyo-ku, Kyoto, 606-8501, Japan
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