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Dekkers MC, Lambooij JM, Pu X, Fagundes RR, Enciso-Martinez A, Kats K, Giepmans BNG, Guigas B, Zaldumbide A. Extracellular vesicles derived from stressed beta cells mediate monocyte activation and contribute to islet inflammation. Front Immunol 2024; 15:1393248. [PMID: 39114661 PMCID: PMC11303142 DOI: 10.3389/fimmu.2024.1393248] [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: 02/28/2024] [Accepted: 07/08/2024] [Indexed: 08/10/2024] Open
Abstract
Objective Beta cell destruction in type 1 diabetes (T1D) results from the combined effect of inflammation and recurrent autoimmunity. In recent years, the role played by beta cells in the development of T1D has evolved from passive victims of the immune system to active contributors in their own destruction. We and others have demonstrated that perturbations in the islet microenvironment promote endoplasmic reticulum (ER) stress in beta cells, leading to enhanced immunogenicity. Among the underlying mechanisms, secretion of extracellular vesicles (EVs) by beta cells has been suggested to mediate the crosstalk with the immune cell compartment. Methods To study the role of cellular stress in the early events of T1D development, we generated a novel cellular model for constitutive ER stress by modulating the expression of HSPA5, which encodes BiP/GRP78, in EndoC-βH1 cells. To investigate the role of EVs in the interaction between beta cells and the immune system, we characterized the EV miRNA cargo and evaluated their effect on innate immune cells. Results Analysis of the transcriptome showed that HSPA5 knockdown resulted in the upregulation of signaling pathways involved in the unfolded protein response (UPR) and changes the miRNA content of EVs, including reduced levels of miRNAs involved in IL-1β signaling. Treatment of primary human monocytes with EVs from stressed beta cells resulted in increased surface expression of CD11b, HLA-DR, CD40 and CD86 and upregulation of IL-1β and IL-6. Conclusion These findings indicate that the content of EVs derived from stressed beta cells can be a mediator of islet inflammation.
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Affiliation(s)
- Mette C. Dekkers
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Joost M. Lambooij
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
- Leiden University Center of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Xudong Pu
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Raphael R. Fagundes
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Agustin Enciso-Martinez
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
- Oncode institute, Leiden University Medical Center, Leiden, Netherlands
- Amsterdam Vesicle Center, Biomedical Engineering and Physics and Laboratory of Experimental Clinical Chemistry, Amsterdam University Medical Center (UMC), University of Amsterdam, Amsterdam, Netherlands
| | - Kim Kats
- Department of Biomedical Sciences, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Ben N. G. Giepmans
- Department of Biomedical Sciences, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Bruno Guigas
- Leiden University Center of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Arnaud Zaldumbide
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
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2
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Callebaut A, Guyer P, Derua R, Buitinga M, Manganaro A, Yi X, Sodré FMC, Vig S, Suleiman M, Marchetti P, Eizirik DL, Kent SC, Mathieu C, James EA, Overbergh L. CD4+ T Cells From Individuals With Type 1 Diabetes Respond to a Novel Class of Deamidated Peptides Formed in Pancreatic Islets. Diabetes 2024; 73:728-742. [PMID: 38387030 PMCID: PMC11043062 DOI: 10.2337/db23-0588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 02/05/2024] [Indexed: 02/24/2024]
Abstract
The β-cell plays a crucial role in the pathogenesis of type 1 diabetes, in part through the posttranslational modification of self-proteins by biochemical processes such as deamidation. These neoantigens are potential triggers for breaking immune tolerance. We report the detection by LC-MS/MS of 16 novel Gln and 27 novel Asn deamidations in 14 disease-related proteins within inflammatory cytokine-stressed human islets of Langerhans. T-cell clones responsive against one Gln- and three Asn-deamidated peptides could be isolated from peripheral blood of individuals with type 1 diabetes. Ex vivo HLA class II tetramer staining detected higher T-cell frequencies in individuals with the disease compared with control individuals. Furthermore, there was a positive correlation between the frequencies of T cells specific for deamidated peptides, insulin antibody levels at diagnosis, and duration of disease. These results highlight that stressed human islets are prone to enzymatic and biochemical deamidation and suggest that both Gln- and Asn-deamidated peptides can promote the activation and expansion of autoreactive CD4+ T cells. These findings add to the growing evidence that posttranslational modifications undermine tolerance and may open the road for the development of new diagnostic and therapeutic applications for individuals living with type 1 diabetes. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Aïsha Callebaut
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
- Center for Translational Immunology, Benaroya Research Institute, Seattle, WA
| | - Perrin Guyer
- Center for Translational Immunology, Benaroya Research Institute, Seattle, WA
| | - Rita Derua
- Laboratory of Protein Phosphorylation and Proteomics, KU Leuven, Leuven, Belgium
| | - Mijke Buitinga
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Anthony Manganaro
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA
| | - Xiaoyan Yi
- ULB Center for Diabetes Research, Medical Faculty, Université Libre de Bruxelles, Brussels, Belgium
| | | | - Saurabh Vig
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Mara Suleiman
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Decio L. Eizirik
- ULB Center for Diabetes Research, Medical Faculty, Université Libre de Bruxelles, Brussels, Belgium
| | - Sally C. Kent
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA
| | - Chantal Mathieu
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Eddie A. James
- Center for Translational Immunology, Benaroya Research Institute, Seattle, WA
| | - Lut Overbergh
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
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3
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Shahedi F, Foma AM, Mahmoudi-Aznaveh A, Mazlomi MA, Azizi Z, Khorramizadeh MR. Differentiation of Pancreatic Beta Cells: Dual Acting of Inflammatory Factors. Curr Stem Cell Res Ther 2024; 19:832-839. [PMID: 37150985 DOI: 10.2174/1574888x18666230504093649] [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: 12/20/2022] [Revised: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 05/09/2023]
Abstract
In the past decades, scientists have made outstanding efforts to treat diabetes. However, diabetes treatment is still far from satisfactory due to the complex nature of the disease and the challenges encountered in resolving it. Inflammatory factors are key regulators of the immune system's response to pathological insults, organ neogenesis, rejuvenation of novel cells to replace injured cells and overwhelming disease conditions. Currently, the available treatments for type 1 diabetes include daily insulin injection, pancreatic beta cell or tissue transplantation, and gene therapy. Cell therapy, exploiting differentiation, and reprogramming various types of cells to generate pancreatic insulin-producing cells are novel approaches for the treatment of type 1 diabetes. A better understanding of the inflammatory pathways offers valuable and improved therapeutic options to provide more advanced and better treatments for diabetes. In this review, we investigated different types of inflammatory factors that participate in the pathogenesis of type 1 diabetes, their possible dual impacts on the differentiation, reprogramming, and fusion of other stem cell lines into pancreatic insulin-producing beta cells, and the possibility of applying these factors to improve the treatment of this disease.
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Affiliation(s)
- Faeze Shahedi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Arron Munggela Foma
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Azam Mahmoudi-Aznaveh
- Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Mazlomi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Zahra Azizi
- Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Khorramizadeh
- Biosensor Research Center, Endocrinology and Metabolism Molecular- Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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4
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Lerner A, Benzvi C, Vojdani A. Cross-reactivity and sequence similarity between microbial transglutaminase and human tissue antigens. Sci Rep 2023; 13:17526. [PMID: 37845267 PMCID: PMC10579360 DOI: 10.1038/s41598-023-44452-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/09/2023] [Indexed: 10/18/2023] Open
Abstract
Microbial transglutaminase (mTG) is a bacterial survival factor, frequently used as a food additive to glue processed nutrients. As a result, new immunogenic epitopes are generated that might drive autoimmunity. Presently, its contribution to autoimmunity through epitope similarity and cross-reactivity was investigated. Emboss Matcher was used to perform sequence alignment between mTG and various antigens implicated in many autoimmune diseases. Monoclonal and polyclonal antibodies made specifically against mTG were applied to 77 different human tissue antigens using ELISA. Six antigens were detected to share significant homology with mTG immunogenic sequences, representing major targets of common autoimmune conditions. Polyclonal antibody to mTG reacted significantly with 17 out of 77 tissue antigens. This reaction was most pronounced with mitochondrial M2, ANA, and extractable nuclear antigens. The results indicate that sequence similarity and cross-reactivity between mTG and various tissue antigens are possible, supporting the relationship between mTG and the development of autoimmune disorders 150W.
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Affiliation(s)
- Aaron Lerner
- Chaim Sheba Medical Center, The Zabludowicz Research Center for Autoimmune Diseases, Tel Hashomer, Israel.
- Ariel University, Ariel, Israel.
| | - Carina Benzvi
- Chaim Sheba Medical Center, The Zabludowicz Research Center for Autoimmune Diseases, Tel Hashomer, Israel
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5
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Mo S, Wang Y, Wu W, Zhao H, Jiang H, Qin S. Identifying target ion channel-related genes to construct a diagnosis model for insulinoma. Front Genet 2023; 14:1181307. [PMID: 37772258 PMCID: PMC10523017 DOI: 10.3389/fgene.2023.1181307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 08/25/2023] [Indexed: 09/30/2023] Open
Abstract
Background: Insulinoma is the most common functional pancreatic neuroendocrine tumor (PNET) with abnormal insulin hypersecretion. The etiopathogenesis of insulinoma remains indefinable. Based on multiple bioinformatics methods and machine learning algorithms, this study proposed exploring the molecular mechanism from ion channel-related genes to establish a genetic diagnosis model for insulinoma. Methods: The mRNA expression profile dataset of GSE73338 was applied to the analysis, which contains 17 insulinoma samples, 63 nonfunctional PNET (NFPNET) samples, and four normal islet samples. Differently expressed ion channel-related genes (DEICRGs) enrichment analyses were performed. We utilized the protein-protein interaction (PPI) analysis and machine learning of LASSO and support vector machine-recursive feature elimination (SVM-RFE) to identify the target genes. Based on these target genes, a nomogram diagnostic model was constructed and verified by a receiver operating characteristic (ROC) curve. Moreover, immune infiltration analysis, single-gene gene set enrichment analysis (GSEA), and gene set variation analysis (GSVA) were executed. Finally, a drug-gene interaction network was constructed. Results: We identified 29 DEICRGs, and enrichment analyses indicated they were primarily enriched in ion transport, cellular ion homeostasis, pancreatic secretion, and lysosome. Moreover, the PPI network and machine learning recognized three target genes (MCOLN1, ATP6V0E1, and ATP4A). Based on these target genes, we constructed an efficiently predictable diagnosis model for identifying insulinomas with a nomogram and validated it with the ROC curve (AUC = 0.801, 95% CI 0.674-0.898). Then, single-gene GSEA analysis revealed that these target genes had a significantly positive correlation with insulin secretion and lysosome. In contrast, the TGF-beta signaling pathway was negatively associated with them. Furthermore, statistically significant discrepancies in immune infiltration were revealed. Conclusion: We identified three ion channel-related genes and constructed an efficiently predictable diagnosis model to offer a novel approach for diagnosing insulinoma.
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Affiliation(s)
- Shuangyang Mo
- Gastroenterology Department, Liuzhou People’s Hospital Affiliated to Guangxi Medical University, Liuzhou, China
- Gastroenterology Department, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Yingwei Wang
- Gastroenterology Department, Liuzhou People’s Hospital Affiliated to Guangxi Medical University, Liuzhou, China
| | - Wenhong Wu
- Gastroenterology Department, Liuzhou People’s Hospital Affiliated to Guangxi Medical University, Liuzhou, China
| | - Huaying Zhao
- Gastroenterology Department, Liuzhou People’s Hospital Affiliated to Guangxi Medical University, Liuzhou, China
| | - Haixing Jiang
- Gastroenterology Department, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Shanyu Qin
- Gastroenterology Department, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
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6
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Moustakas AK, Nguyen H, James EA, Papadopoulos GK. Autoimmune susceptible HLA class II motifs facilitate the presentation of modified neoepitopes to potentially autoreactive T cells. Cell Immunol 2023; 390:104729. [PMID: 37301094 DOI: 10.1016/j.cellimm.2023.104729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/27/2023] [Accepted: 05/11/2023] [Indexed: 06/12/2023]
Abstract
Rheumatoid arthritis (RA), multiple sclerosis (MS), type 1 diabetes (T1D), and celiac disease (CD), are strongly associated with susceptible HLA class II haplotypes. The peptide-binding pockets of these molecules are polymorphic, thus each HLA class II protein presents a distinct set of peptides to CD4+ T cells. Peptide diversity is increased through post-translational modifications, generating non-templated sequences that enhance HLA binding and/or T cell recognition. The high-risk HLA-DR alleles that confer susceptibility to RA are notable for their ability to accommodate citrulline, promoting responses to citrullinated self-antigens. Likewise, HLA-DQ alleles associated with T1D and CD favor the binding of deamidated peptides. In this review, we discuss structural features that promote modified self-epitope presentation, provide evidence supporting the relevance of T cell recognition of such antigens in disease processes, and make a case that interrupting the pathways that generate such epitopes and reprogramming neoepitope-specific T cells are key strategies for effective therapeutic intervention.
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Affiliation(s)
- Antonis K Moustakas
- Department of Food Science and Technology, Faculty of Environmental Sciences, Ionian University, GR26100 Argostoli, Cephalonia, Greece
| | - Hai Nguyen
- Center for Translational Immunology, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
| | - Eddie A James
- Center for Translational Immunology, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA.
| | - George K Papadopoulos
- Laboratory of Biophysics, Biochemistry, Bioprocessing and Bioproducts, Faculty of Agricultural Technology, Technological Educational Institute of Epirus, GR47100 Arta, Greece
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7
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Lichti CF, Wan X. Using mass spectrometry to identify neoantigens in autoimmune diseases: The type 1 diabetes example. Semin Immunol 2023; 66:101730. [PMID: 36827760 PMCID: PMC10324092 DOI: 10.1016/j.smim.2023.101730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/24/2023]
Abstract
In autoimmune diseases, recognition of self-antigens presented by major histocompatibility complex (MHC) molecules elicits unexpected attack of tissue by autoantibodies and/or autoreactive T cells. Post-translational modification (PTM) may alter the MHC-binding motif or TCR contact residues in a peptide antigen, transforming the tolerance to self to autoreactivity. Mass spectrometry-based immunopeptidomics provides a valuable mechanism for identifying MHC ligands that contain PTMs and can thus provide valuable insights into pathogenesis and therapeutics of autoimmune diseases. A plethora of PTMs have been implicated in this process, and this review highlights their formation and identification.
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Affiliation(s)
- Cheryl F Lichti
- Department of Pathology and Immunology, Division of Immunobiology, The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8118, St. Louis, MO 63110, USA.
| | - Xiaoxiao Wan
- Department of Pathology and Immunology, Division of Immunobiology, The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8118, St. Louis, MO 63110, USA.
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8
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Foster A, Bhattacharjee P, Tresoldi E, Pakusch M, Cameron FJ, Mannering SI. Glutamine deamidation does not increase the immunogenicity of C-peptide in people with type 1 diabetes. J Transl Autoimmun 2022; 6:100180. [PMID: 36619657 PMCID: PMC9811213 DOI: 10.1016/j.jtauto.2022.100180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/18/2022] [Accepted: 12/19/2022] [Indexed: 12/28/2022] Open
Abstract
Type 1 diabetes (T1D) is a T-cell mediated autoimmune disease in which the insulin-producing beta cells are destroyed. While it is clear that full-length C-peptide, derived from proinsulin, is a major antigen in human T1D it is not clear how and why C-peptide becomes a target of the autoimmune CD4+ T-cell responses in T1D. Neoepitopes formed by the conversion of glutamine (Q) residues to glutamic acid (E) by deamidation are central to the immune pathogenesis of coeliac disease and have been implicated in autoimmune responses in T1D. Here, we asked if the immunogenicity of full-length C-peptide, which comprises four glutamine residues, was enhanced by deamidation, which we mimicked by substituting glutamic acid for glutamine residue. First, we used a panel of 18 well characterized CD4+ T-cell lines specific for epitopes derived from human C-peptide. In all cases, when the substitution fell within the cognate epitope the response was diminished, or in a few cases unchanged. In contrast, when the substitution fell outside the epitope recognized by the TCR responses were unchanged or slightly augmented. Second, we compared CD4+ T-cell proliferation responses, against deamidated and unmodified C-peptide, in the peripheral blood of people with or without T1D using the CFSE-based proliferation assay. While, as reported previously, responses were detected to unmodified C-peptide, no deamidated C-peptide was consistently more stimulatory than native C-peptide. Overall responses were weaker to deamidated C-peptide compared to unmodified C-peptide. Hence, we conclude that deamidated C-peptide does not play a role in beta-cell autoimmunity in people with T1D.
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Affiliation(s)
- Abby Foster
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia
| | - Pushpak Bhattacharjee
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia
| | - Eleonora Tresoldi
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia
| | - Miha Pakusch
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia
| | - Fergus J. Cameron
- Department of Endocrinology and Diabetes, Royal Children's Hospital, Australia,Murdoch Children's Research Institute, Parkville, VIC, Australia,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Stuart I. Mannering
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Australia,Department of Medicine, University of Melbourne, St. Vincent's Hospital, Fitzroy, Victoria, 3065, Australia,Corresponding author. St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria, 3065, Melbourne, Australia
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9
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Yang ML, Kibbey RG, Mamula MJ. Biomarkers of autoimmunity and beta cell metabolism in type 1 diabetes. Front Immunol 2022; 13:1028130. [PMID: 36389721 PMCID: PMC9647083 DOI: 10.3389/fimmu.2022.1028130] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/13/2022] [Indexed: 09/10/2023] Open
Abstract
Posttranslational protein modifications (PTMs) are an inherent response to physiological changes causing altered protein structure and potentially modulating important biological functions of the modified protein. Besides cellular metabolic pathways that may be dictated by PTMs, the subtle change of proteins also may provoke immune attack in numerous autoimmune diseases. Type 1 diabetes (T1D) is a chronic autoimmune disease destroying insulin-producing beta cells within the pancreatic islets, a result of tissue inflammation to specific autoantigens. This review summarizes how PTMs arise and the potential pathological consequence of PTMs, with particular focus on specific autoimmunity to pancreatic beta cells and cellular metabolic dysfunction in T1D. Moreover, we review PTM-associated biomarkers in the prediction, diagnosis and in monitoring disease activity in T1D. Finally, we will discuss potential preventive and therapeutic approaches of targeting PTMs in repairing or restoring normal metabolic pathways in pancreatic islets.
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Affiliation(s)
- Mei-Ling Yang
- Section of Rheumatology, Allergy and Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Richard G. Kibbey
- Section of Endocrinology, Department of Internal Medicine, Yale University, New Haven, CT, United States
| | - Mark J. Mamula
- Section of Rheumatology, Allergy and Immunology, Department of Internal Medicine, Yale University, New Haven, CT, United States
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10
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Hu A, Zou H, Chen B, Zhong J. Posttranslational modifications in diabetes: Mechanisms and functions. Rev Endocr Metab Disord 2022; 23:1011-1033. [PMID: 35697961 DOI: 10.1007/s11154-022-09740-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/20/2022] [Indexed: 12/15/2022]
Abstract
As one of the most widespread chronic diseases, diabetes and its accompanying complications affect approximately one tenth of individuals worldwide and represent a growing cause of morbidity and mortality. Accumulating evidence has proven that the process of diabetes is complex and interactive, involving various cellular responses and signaling cascades by posttranslational modifications (PTMs). Therefore, understanding the mechanisms and functions of PTMs in regulatory networks has fundamental importance for understanding the prediction, onset, diagnosis, progression, and treatment of diabetes. In this review, we offer a holistic summary and illustration of the crosstalk between PTMs and diabetes, including both types 1 and 2. Meanwhile, we discuss the potential use of PTMs in diabetes treatment and provide a prospective direction for deeply understanding the metabolic diseases.
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Affiliation(s)
- Ang Hu
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
| | - Haohong Zou
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
| | - Bin Chen
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
- The First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Jianing Zhong
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China.
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11
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Maggi J, Carrascal M, Soto L, Neira O, Cuéllar MC, Aravena O, James EA, Abian J, Jaraquemada D, Catalan D, Aguillón JC. Isolation of HLA-DR-naturally presented peptides identifies T-cell epitopes for rheumatoid arthritis. Ann Rheum Dis 2022; 81:1096-1105. [PMID: 35459695 DOI: 10.1136/annrheumdis-2021-220371] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/08/2022] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Rheumatoid arthritis (RA) immunopathogenesis revolves around the presentation of poorly characterised self-peptides by human leucocyte antigen (HLA)-class II molecules on the surface of antigen-presenting cells to autoreactive CD4 +T cells. Here, we analysed the HLA-DR-associated peptidome of synovial tissue (ST) and of dendritic cells (DCs) pulsed with synovial fluid (SF) or ST, to identify potential T-cell epitopes for RA. METHODS HLA-DR/peptide complexes were isolated from RA ST samples (n=3) and monocyte-derived DCs, generated from healthy donors carrying RA-associated shared epitope positive HLA-DR molecules and pulsed with RA SF (n=7) or ST (n=2). Peptide sequencing was performed by high-resolution mass spectrometry. The immunostimulatory capacity of selected peptides was evaluated on peripheral blood mononuclear cells from patients with RA (n=29) and healthy subjects (n=12) by flow cytometry. RESULTS We identified between 103 and 888 HLA-DR-naturally presented peptides per sample. We selected 37 native and six citrullinated (cit)-peptides for stimulation assays. Six of these peptides increased the expression of CD40L on CD4 +T cells patients with RA, and specifically triggered IFN-γ expression on RA CD4 +T cells compared with healthy subjects. Finally, the frequency of IFN-γ-producing CD4 +T cells specific for a myeloperoxidase-derived peptide showed a positive correlation with disease activity. CONCLUSIONS We significantly expanded the peptide repertoire presented by HLA-DR molecules in a physiologically relevant context, identifying six new epitopes recognised by CD4 +T cells from patients with RA. This information is important for a better understanding of the disease immunopathology, as well as for designing tolerising antigen-specific immunotherapies.
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Affiliation(s)
- Jaxaira Maggi
- Immune Regulation and Tolerance Research Group, Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile Facultad de Medicina, Santiago, Chile
| | - Montserrat Carrascal
- Biological and Environmental Proteomics Group, IIBB-CSIC, IDIBAPS, Barcelona, Spain
| | - Lilian Soto
- Immune Regulation and Tolerance Research Group, Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile Facultad de Medicina, Santiago, Chile
- Departamento de Medicina, Unidad del Dolor, Hospital Clinico de la Universidad de Chile Jose Joaquin Aguirre, Santiago, Chile
| | - Oscar Neira
- Servicio de Reumatología, Hospital del Salvador, Universidad de Chile, Santiago, Chile
| | - María C Cuéllar
- Servicio de Reumatología, Hospital del Salvador, Universidad de Chile, Santiago, Chile
| | - Octavio Aravena
- Immune Regulation and Tolerance Research Group, Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile Facultad de Medicina, Santiago, Chile
| | - Eddie A James
- Translational Research Program, Benaroya Research Institute, Seattle, Washington, USA
| | - Joaquin Abian
- Biological and Environmental Proteomics Group, IIBB-CSIC, IDIBAPS, Barcelona, Spain
| | - Dolores Jaraquemada
- Immunology Unit, Cell Biology, Physiology and Immunology Department, Institut de Biotecnologia i Biomedicina, Universitat de Barcelona, Barcelona, Spain
| | - Diego Catalan
- Immune Regulation and Tolerance Research Group, Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile Facultad de Medicina, Santiago, Chile
| | - Juan C Aguillón
- Immune Regulation and Tolerance Research Group, Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Universidad de Chile Facultad de Medicina, Santiago, Chile
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12
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den Hollander NHM, Roep BO. From Disease and Patient Heterogeneity to Precision Medicine in Type 1 Diabetes. Front Med (Lausanne) 2022; 9:932086. [PMID: 35903316 PMCID: PMC9314738 DOI: 10.3389/fmed.2022.932086] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/13/2022] [Indexed: 12/12/2022] Open
Abstract
Type 1 diabetes (T1D) remains a devastating disease that requires much effort to control. Life-long daily insulin injections or an insulin pump are required to avoid severe complications. With many factors contributing to disease onset, T1D is a complex disease to cure. In this review, the risk factors, pathophysiology and defect pathways are discussed. Results from (pre)clinical studies are highlighted that explore restoration of insulin production and reduction of autoimmunity. It has become clear that treatment responsiveness depends on certain pathophysiological or genetic characteristics that differ between patients. For instance, age at disease manifestation associated with efficacy of immune intervention therapies, such as depleting islet-specific effector T cells or memory B cells and increasing immune regulation. The new challenge is to determine in whom to apply which intervention strategy. Within patients with high rates of insulitis in early T1D onset, therapy depleting T cells or targeting B lymphocytes may have a benefit, whereas slow progressing T1D in adults may be better served with more sophisticated, precise and specific disease modifying therapies. Genetic barcoding and immune profiling may help determining from which new T1D endotypes patients suffer. Furthermore, progressed T1D needs replenishment of insulin production besides autoimmunity reversal, as too many beta cells are already lost or defect. Recurrent islet autoimmunity and allograft rejection or necrosis seem to be the most challenging obstacles. Since beta cells are highly immunogenic under stress, treatment might be more effective with stress reducing agents such as glucagon-like peptide 1 (GLP-1) analogs. Moreover, genetic editing by CRISPR-Cas9 allows to create hypoimmunogenic beta cells with modified human leukocyte antigen (HLA) expression that secrete immune regulating molecules. Given the differences in T1D between patients, stratification of endotypes in clinical trials seems essential for precision medicines and clinical decision making.
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Affiliation(s)
- Nicoline H M den Hollander
- Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands.,Graduate School, Utrecht University, Utrecht, Netherlands
| | - Bart O Roep
- Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
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13
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Gootjes C, Zwaginga JJ, Roep BO, Nikolic T. Functional Impact of Risk Gene Variants on the Autoimmune Responses in Type 1 Diabetes. Front Immunol 2022; 13:886736. [PMID: 35603161 PMCID: PMC9114814 DOI: 10.3389/fimmu.2022.886736] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/08/2022] [Indexed: 11/17/2022] Open
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that develops in the interplay between genetic and environmental factors. A majority of individuals who develop T1D have a HLA make up, that accounts for 50% of the genetic risk of disease. Besides these HLA haplotypes and the insulin region that importantly contribute to the heritable component, genome-wide association studies have identified many polymorphisms in over 60 non-HLA gene regions that also contribute to T1D susceptibility. Combining the risk genes in a score (T1D-GRS), significantly improved the prediction of disease progression in autoantibody positive individuals. Many of these minor-risk SNPs are associated with immune genes but how they influence the gene and protein expression and whether they cause functional changes on a cellular level remains a subject of investigation. A positive correlation between the genetic risk and the intensity of the peripheral autoimmune response was demonstrated both for HLA and non-HLA genetic risk variants. We also observed epigenetic and genetic modulation of several of these T1D susceptibility genes in dendritic cells (DCs) treated with vitamin D3 and dexamethasone to acquire tolerogenic properties as compared to immune activating DCs (mDC) illustrating the interaction between genes and environment that collectively determines risk for T1D. A notion that targeting such genes for therapeutic modulation could be compatible with correction of the impaired immune response, inspired us to review the current knowledge on the immune-related minor risk genes, their expression and function in immune cells, and how they may contribute to activation of autoreactive T cells, Treg function or β-cell apoptosis, thus contributing to development of the autoimmune disease.
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Affiliation(s)
- Chelsea Gootjes
- Laboratory of Immunomodulation and Regenerative Cell Therapy, Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
| | - Jaap Jan Zwaginga
- Laboratory of Immunomodulation and Regenerative Cell Therapy, Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
| | - Bart O Roep
- Laboratory of Immunomodulation and Regenerative Cell Therapy, Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
| | - Tatjana Nikolic
- Laboratory of Immunomodulation and Regenerative Cell Therapy, Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
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14
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Hu A, Hu Z, Ye J, Liu Y, Lai Z, Zhang M, Ji W, Huang L, Zou H, Chen B, Zhong J. Metformin exerts anti-tumor effects via Sonic hedgehog signaling pathway by targeting AMPK in HepG2 cells. Biochem Cell Biol 2022; 100:142-151. [PMID: 34990285 DOI: 10.1139/bcb-2021-0409] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Metformin, a traditional first-line pharmacologic treatment for type 2 diabetes, has recently been shown to impart anti-cancer effects on hepatocellular carcinoma (HCC). However, the molecular mechanism of metformin on its antitumor activity is still not completely clear. The Sonic hedgehog (Shh) signaling pathway is closely associated with the initiation and progression of HCC. Therefore, the aim of the current study was to investigate the effects of metformin on the biological behavior of HCC and the underlying functional mechanism of metformin on the Shh pathway. The HCC cellular was induced in HepG2 cells by recombinant human Shh (rhShh). The effects of metformin on proliferation and metastasis were evaluated by proliferation, wound healing and invasion assays in vitro. The mRNA and protein expression levels of proteins related to the Shh pathway were measured by western blotting, quantitative PCR and immunofluorescence staining. Metformin inhibited rhShh-induced proliferation and metastasis. Furthermore, metformin decreased mRNA and protein expression of components of the Shh pathway including Shh, Ptch, Smo and Gli-1. Silencing of AMPK in the presence of metformin revealed that metformin could exert its inhibitory effect via AMPK. Our findings demonstrate that metformin can suppress the migration and invasion of HepG2 cells via AMPK-mediated inhibition of the Shh pathway.
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Affiliation(s)
- Ang Hu
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Zeming Hu
- First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China;
| | - Jianming Ye
- First Affiliated Hospital of Gannan Medical University, 477808, Ganzhou, Jiangxi, China;
| | - Yuwen Liu
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Zhonghong Lai
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Mi Zhang
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Weichao Ji
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Lili Huang
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Haohong Zou
- Gannan Medical University, 74554, Ganzhou, Jiangxi, China;
| | - Bin Chen
- First Affiliated Hospital of Gannan Medical University, 477808, Ganzhou, Jiangxi, China;
| | - Jianing Zhong
- Gannan Medical University, 74554, Ganzhou, China, 341000;
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15
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Callebaut A, Bruggeman Y, Zamit C, Sodré FMC, Irla M, Mathieu C, Buitinga M, Overbergh L. Aberrant expression of transglutaminase 2 in pancreas and thymus of NOD mice underscores the importance of deamidation in neoantigen generation. Front Endocrinol (Lausanne) 2022; 13:908248. [PMID: 35966081 PMCID: PMC9367685 DOI: 10.3389/fendo.2022.908248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 07/06/2022] [Indexed: 11/17/2022] Open
Abstract
Post-translational modifications can lead to a break in immune tolerance in autoimmune diseases such as type 1 diabetes (T1D). Deamidation, the conversion of glutamine to glutamic acid by transglutaminase (TGM) enzymes, is a post-translational modification of interest, with deamidated peptides being reported as autoantigens in T1D. However, little is known about how Tgm2, the most ubiquitously expressed Tgm isoform, is regulated and how tolerance against deamidated peptides is lost. Here, we report on the aberrant expression and regulation of Tgm2 in the pancreas and thymus of NOD mice. We demonstrate that Tgm2 expression is induced by the inflammatory cytokines IL1β and IFNγ in a synergistic manner and that murine pancreatic islets of NOD mice have higher Tgm2 levels, while Tgm2 levels in medullary thymic epithelial cells are reduced. We thus provide the first direct evidence to our knowledge that central tolerance establishment against deamidated peptides might be impaired due to lower Tgm2 expression in NOD medullary thymic epithelial cells, which together with the aberrantly high levels of deamidated peptides in NOD β-cells underscores the role of deamidation in amplifying T-cell reactivity.
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Affiliation(s)
- Aїsha Callebaut
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
| | - Ylke Bruggeman
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
| | - Cloé Zamit
- CNRS, INSERM, Centre d’Immunologie de Marseille-Luminy, Aix-Marseille University, Marseille, France
| | - Fernanda Marques Câmara Sodré
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
- Department of Microbiology, University of Sao Paulo, Sao Paulo, Brazil
| | - Magali Irla
- CNRS, INSERM, Centre d’Immunologie de Marseille-Luminy, Aix-Marseille University, Marseille, France
| | - Chantal Mathieu
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
| | - Mijke Buitinga
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
- Department of Nutrition and Movement Sciences, Maastricht University, Maastricht, Netherlands
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, Netherlands
| | - Lut Overbergh
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
- *Correspondence: Lut Overbergh,
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16
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Catriona C, Paolo P. SARS-CoV-2 induced post-translational protein modifications: A trigger for developing autoimmune diabetes? Diabetes Metab Res Rev 2022; 38:e3508. [PMID: 34990520 PMCID: PMC9015335 DOI: 10.1002/dmrr.3508] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Emerging evidence indicates a bi-directional relationship between SARS-CoV-2 and diabetes. The possibility exists that SARS-CoV-2 could induce diabetes, but it is not yet clear whether this might be a fulminant-type diabetes, autoimmune diabetes, or a new-onset transient hyperglycaemia. This viewpoint discusses mechanisms by which SARS-CoV-2 might trigger type 1 diabetes mellitus (T1DM). Specifically, we looked at the role of post-translational protein modifications (PTMs) and the generation of neoepitopes as a potential mechanism in the induction of islet autoimmunity, and the pathways via which coronavirus infections might exacerbate the formation of PTMs and, in so doing, provoke the onset of T1DM.
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Affiliation(s)
| | - Pozzilli Paolo
- Department of MedicineUnit of Endocrinology and DiabetesCampus Bio‐Medico UniversityRomeItaly
- Blizard InstituteBarts and The London School of Medicine and DentistryUniversity of LondonLondonUK
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17
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Thomaidou S, Slieker RC, van der Slik AR, Boom J, Mulder F, Munoz-Garcia A, 't Hart LM, Koeleman B, Carlotti F, Hoeben RC, Roep BO, Mei H, Zaldumbide A. Long RNA Sequencing and Ribosome Profiling of Inflamed β-Cells Reveal an Extensive Translatome Landscape. Diabetes 2021; 70:2299-2312. [PMID: 34554924 DOI: 10.2337/db20-1122] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 06/11/2021] [Indexed: 11/13/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease characterized by autoreactive T cell-mediated destruction of the insulin-producing pancreatic β-cells. Increasing evidence suggest that the β-cells themselves contribute to their own destruction by generating neoantigens through the production of aberrant or modified proteins that escape central tolerance. We recently demonstrated that ribosomal infidelity amplified by stress could lead to the generation of neoantigens in human β-cells, emphasizing the participation of nonconventional translation events in autoimmunity, as occurring in cancer or virus-infected tissues. Using a transcriptome-wide profiling approach to map translation initiation start sites in human β-cells under standard and inflammatory conditions, we identify a completely new set of polypeptides derived from noncanonical start sites and translation initiation within long noncoding RNA. Our data underline the extreme diversity of the β-cell translatome and may reveal new functional biomarkers for β-cell distress, disease prediction and progression, and therapeutic intervention in T1D.
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Affiliation(s)
- Sofia Thomaidou
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Roderick C Slieker
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
- Department of Epidemiology and Biostatistics, Amsterdam Public Health Institute, Amsterdam UMC, location VUMC, Amsterdam, the Netherlands
| | - Arno R van der Slik
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands
| | - Jasper Boom
- Sequencing Analysis Support Core, Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, the Netherlands
| | - Flip Mulder
- Center for Molecular Medicine, Utrecht Medical Center, Utrecht, the Netherlands
| | - Amadeo Munoz-Garcia
- Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Leen M 't Hart
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Bobby Koeleman
- Center for Molecular Medicine, Utrecht Medical Center, Utrecht, the Netherlands
| | - Françoise Carlotti
- Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Rob C Hoeben
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Bart O Roep
- Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Department of Diabetes Immunology, Arthur Riggs Diabetes & Metabolism Research Institute, City of Hope, Duarte, CA
| | - Hailiang Mei
- Sequencing Analysis Support Core, Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, the Netherlands
| | - Arnaud Zaldumbide
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, the Netherlands
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18
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Amdare N, Purcell AW, DiLorenzo TP. Noncontiguous T cell epitopes in autoimmune diabetes: From mice to men and back again. J Biol Chem 2021; 297:100827. [PMID: 34044020 PMCID: PMC8233151 DOI: 10.1016/j.jbc.2021.100827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 11/30/2022] Open
Abstract
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that affects the insulin-producing beta cells of the pancreatic islets. The nonobese diabetic mouse is a widely studied spontaneous model of the disease that has contributed greatly to our understanding of T1D pathogenesis. This is especially true in the case of antigen discovery. Upon review of existing knowledge concerning the antigens and peptide epitopes that are recognized by T cells in this model, good concordance is observed between mouse and human antigens. A fascinating recent illustration of the contribution of the nonobese diabetic mouse in the area of epitope identification is the discovery of noncontiguous CD4+ T cell epitopes. This novel epitope class is characterized by the linkage of an insulin-derived peptide to, most commonly, a fragment of a natural cleavage product of another beta cell secretory granule constituent. These so-called hybrid insulin peptides are also recognized by T cells in patients with T1D, although the precise mechanism for their generation has yet to be defined and is the subject of active investigation. Although evidence from the tumor immunology arena documented the existence of noncontiguous CD8+ T cell epitopes, generated by proteasome-mediated peptide splicing involving transpeptidation, such CD8+ T cell epitopes were thought to be a rare immunological curiosity. However, recent advances in bioinformatics and mass spectrometry have challenged this view. These developments, coupled with the discovery of hybrid insulin peptides, have spurred a search for noncontiguous CD8+ T cell epitopes in T1D, an exciting frontier area still in its infancy.
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Affiliation(s)
- Nitin Amdare
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Teresa P DiLorenzo
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA; Division of Endocrinology, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, USA; Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York, USA; The Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, New York, USA.
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19
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Vig S, Lambooij JM, Zaldumbide A, Guigas B. Endoplasmic Reticulum-Mitochondria Crosstalk and Beta-Cell Destruction in Type 1 Diabetes. Front Immunol 2021; 12:669492. [PMID: 33936111 PMCID: PMC8085402 DOI: 10.3389/fimmu.2021.669492] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022] Open
Abstract
Beta-cell destruction in type 1 diabetes (T1D) results from the combined effect of inflammation and recurrent autoimmunity. In response to inflammatory signals, beta-cells engage adaptive mechanisms where the endoplasmic reticulum (ER) and mitochondria act in concert to restore cellular homeostasis. In the recent years it has become clear that this adaptive phase may trigger the development of autoimmunity by the generation of autoantigens recognized by autoreactive CD8 T cells. The participation of the ER stress and the unfolded protein response to the increased visibility of beta-cells to the immune system has been largely described. However, the role of the other cellular organelles, and in particular the mitochondria that are central mediator for beta-cell survival and function, remains poorly investigated. In this review we will dissect the crosstalk between the ER and mitochondria in the context of T1D, highlighting the key role played by this interaction in beta-cell dysfunctions and immune activation, especially through regulation of calcium homeostasis, oxidative stress and generation of mitochondrial-derived factors.
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Affiliation(s)
- Saurabh Vig
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Joost M. Lambooij
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Arnaud Zaldumbide
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Bruno Guigas
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
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20
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Roep BO, Thomaidou S, van Tienhoven R, Zaldumbide A. Type 1 diabetes mellitus as a disease of the β-cell (do not blame the immune system?). Nat Rev Endocrinol 2021; 17:150-161. [PMID: 33293704 PMCID: PMC7722981 DOI: 10.1038/s41574-020-00443-4] [Citation(s) in RCA: 233] [Impact Index Per Article: 77.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/04/2020] [Indexed: 02/07/2023]
Abstract
Type 1 diabetes mellitus is believed to result from destruction of the insulin-producing β-cells in pancreatic islets that is mediated by autoimmune mechanisms. The classic view is that autoreactive T cells mistakenly destroy healthy ('innocent') β-cells. We propose an alternative view in which the β-cell is the key contributor to the disease. By their nature and function, β-cells are prone to biosynthetic stress with limited measures for self-defence. β-Cell stress provokes an immune attack that has considerable negative effects on the source of a vital hormone. This view would explain why immunotherapy at best delays progression of type 1 diabetes mellitus and points to opportunities to use therapies that revitalize β-cells, in combination with immune intervention strategies, to reverse the disease. We present the case that dysfunction occurs in both the immune system and β-cells, which provokes further dysfunction, and present the evidence leading to the consensus that islet autoimmunity is an essential component in the pathogenesis of type 1 diabetes mellitus. Next, we build the case for the β-cell as the trigger of an autoimmune response, supported by analogies in cancer and antitumour immunity. Finally, we synthesize a model ('connecting the dots') in which both β-cell stress and islet autoimmunity can be harnessed as targets for intervention strategies.
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Affiliation(s)
- Bart O Roep
- Department of Diabetes Immunology, Diabetes & Metabolism Research Institute, Beckman Research Institute at City of Hope, Los Angeles, CA, USA.
- Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands.
| | - Sofia Thomaidou
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - René van Tienhoven
- Department of Diabetes Immunology, Diabetes & Metabolism Research Institute, Beckman Research Institute at City of Hope, Los Angeles, CA, USA
| | - Arnaud Zaldumbide
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
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21
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Callebaut A, Derua R, Vig S, Delong T, Mathieu C, Overbergh L. Identification of Deamidated Peptides in Cytokine-Exposed MIN6 Cells through LC-MS/MS Using a Shortened Digestion Time and Inspection of MS2 Spectra. J Proteome Res 2020; 20:1405-1414. [PMID: 33372785 DOI: 10.1021/acs.jproteome.0c00801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Enzymatic deamidation, the conversion of glutamine (Gln) into glutamic acid (Glu) residues, mediated by tissue transglutaminase enzymes, can provoke autoimmunity by generating altered self-epitopes, a process well-known in celiac disease and more recently also described in type 1 diabetes (T1D). To identify deamidated proteins, liquid chromatography-tandem mass spectrometry is the method of choice. However, as nonenzymatic deamidations on asparagine (Asn) and to a minor extent on Gln are frequently induced in vitro during proteomics sample preparation, the accurate detection of in vivo deamidation can be hampered. Here we report on the optimization of a method to reduce in vitro generated deamidation by 70% using improved trypsin digestion conditions (90 min/pH 8). We also point to the critical importance of manual inspection of MS2 spectra, considering that only 55% of the high quality peptides with Gln deamidation were assigned correctly using an automated search algorithm. As proof of principal, using these criteria, we showed a significant increase in levels of both Asn and Gln deamidation in cytokine-exposed murine MIN6 β-cells, paralleled by an increase in tissue transglutaminase activity. These findings add evidence to the hypothesis that deamidation is occurring in stressed β-cell proteins and can be involved in the autoimmune process in T1D.
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Affiliation(s)
- Aïsha Callebaut
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, 3000 Leuven, Belgium
| | - Rita Derua
- Laboratory of Protein Phosphorylation and Proteomics, KU Leuven, 3000 Leuven, Belgium.,SyBioMa, KU Leuven, 3000 Leuven, Belgium
| | - Saurabh Vig
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, 3000 Leuven, Belgium
| | - Thomas Delong
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz, Aurora, Colorado 80045, United States
| | - Chantal Mathieu
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, 3000 Leuven, Belgium
| | - Lut Overbergh
- Laboratory for Clinical and Experimental Endocrinology, KU Leuven, 3000 Leuven, Belgium
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22
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Akhbari P, Richardson SJ, Morgan NG. Type 1 Diabetes: Interferons and the Aftermath of Pancreatic Beta-Cell Enteroviral Infection. Microorganisms 2020; 8:microorganisms8091419. [PMID: 32942706 PMCID: PMC7565444 DOI: 10.3390/microorganisms8091419] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/09/2020] [Accepted: 09/11/2020] [Indexed: 02/07/2023] Open
Abstract
Enteroviruses (EVs) have long been implicated in the pathogenesis of type 1 diabetes (T1D), and accumulating evidence has associated virus-induced autoimmunity with the loss of pancreatic beta cells in T1D. Inflammatory cytokines including interferons (IFN) form a primary line of defence against viral infections, and their chronic elevation is a hallmark feature of many autoimmune diseases. IFNs play a key role in activating and regulating innate and adaptive immune responses, and to do so they modulate the expression of networks of genes and transcription factors known generically as IFN stimulated genes (ISGs). ISGs in turn modulate critical cellular processes ranging from cellular metabolism and growth regulation to endoplasmic reticulum (ER) stress and apoptosis. More recent studies have revealed that IFNs also modulate gene expression at an epigenetic as well as post-transcriptional and post-translational levels. As such, IFNs form a key link connecting the various genetic, environmental and immunological factors involved in the initiation and progression of T1D. Therefore, gaining an improved understanding of the mechanisms by which IFNs modulate beta cell function and survival is crucial in explaining the pathogenesis of virally-induced T1D. This should provide the means to prevent, decelerate or even reverse beta cell impairment.
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23
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Abstract
Proteins succumb to numerous post-translational modifications (PTMs). These relate to enzymatic or non-enzymatic reactions taking place in either the intracellular or extracellular compartment. While intracellular oxidative changes are mainly due to redox stress, extracellular PTMs may be induced in an inflammatory micro milieu that is rich in reactive species. The increasing recognition of oxidative modifications as a causing agent or side-effect of pathophysiological states and diseases puts oxidative PTMS (oxPTMs) into the spotlight of inflammation research. Pathological hyper-modification of proteins can lead to accumulation, aggregation, cell stress, altered antigenic peptides, and damage-associated molecular pattern (DAMP)-like recognition by host immunity. Such processes are linked to cardiovascular disease and autoinflammation. At the same time, a detailed understanding of the mechanisms governing inflammatory responses to oxPTMs may capitalize on new therapeutic routes for enhancing adaptive immune responses as needed, for instance, in oncology. We here summarize some of the latest developments of oxPTMs in disease diagnosis and therapy. Potential target proteins and upcoming technologies, such as gas plasmas, are outlined for future research that may aid in identifying the molecular basis of immunogenic vs. tolerogenic oxPTMs.
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24
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Balakrishnan S, Kumar P, Prabhakar BS. Post-translational modifications contribute to neoepitopes in Type-1 diabetes: Challenges for inducing antigen-specific tolerance. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140478. [PMID: 32599298 DOI: 10.1016/j.bbapap.2020.140478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 05/20/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022]
Abstract
Type-1 Diabetes (T1D) is the major autoimmune disease affecting the juvenile population in which insulin-producing pancreatic β-cells are destroyed by self-reactive T-cells and B-cells. Emerging studies have identified the presence of autoantibodies and altered T-cell reactivity against several autoantigens in individuals who are at risk of developing T1D even before the clinical onset of diabetes. Whilst these findings could lead to the development of predictive biomarkers for early diagnosis, growing evidence on the generation of neoepitopes, epitope spreading and diverse antigen repertoire in T1D poses a major challenge for developing approaches to induce antigen-specific tolerance. Mechanisms of neoepitope generation include post-translational modifications of existing epitopes, aberrant translational products, peptide fusion, and differences in MHC binding registers. Here, we focus our discussion on how post-translational modifications can give rise to immunogenic neoepitopes in T1D and present our perspective on how it could affect the development of therapeutic approaches to induce antigen-specific tolerance.
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Affiliation(s)
- Sivasangari Balakrishnan
- Department of Microbiology and Immunology, University of Illinois-College of Medicine, Chicago, IL, United States of America.
| | - Prabhakaran Kumar
- Department of Microbiology and Immunology, University of Illinois-College of Medicine, Chicago, IL, United States of America.
| | - Bellur S Prabhakar
- Department of Microbiology and Immunology, University of Illinois-College of Medicine, Chicago, IL, United States of America.
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25
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Nakayasu ES, Qian WJ, Evans-Molina C, Mirmira RG, Eizirik DL, Metz TO. The role of proteomics in assessing beta-cell dysfunction and death in type 1 diabetes. Expert Rev Proteomics 2019; 16:569-582. [PMID: 31232620 PMCID: PMC6628911 DOI: 10.1080/14789450.2019.1634548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/18/2019] [Indexed: 12/17/2022]
Abstract
Introduction: Type 1 diabetes (T1D) is characterized by autoimmune-induced dysfunction and destruction of the pancreatic beta cells. Unfortunately, this process is poorly understood, and the current best treatment for type 1 diabetes is the administration of exogenous insulin. To better understand these mechanisms and to develop new therapies, there is an urgent need for biomarkers that can reliably predict disease stage. Areas covered: Mass spectrometry (MS)-based proteomics and complementary techniques play an important role in understanding the autoimmune response, inflammation and beta-cell death. MS is also a leading technology for the identification of biomarkers. This, and the technical difficulties and new technologies that provide opportunities to characterize small amounts of sample in great depth and to analyze large sample cohorts will be discussed in this review. Expert opinion: Understanding disease mechanisms and the discovery of disease-associated biomarkers are highly interconnected goals. Ideal biomarkers would be molecules specific to the different stages of the disease process that are released from beta cells to the bloodstream. However, such molecules are likely to be present in trace amounts in the blood due to the small number of pancreatic beta cells in the human body and the heterogeneity of the target organ and disease process.
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Affiliation(s)
- Ernesto S. Nakayasu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Wei-Jun Qian
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Carmella Evans-Molina
- Center for Diabetes and Metabolic Diseases, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Raghavendra G. Mirmira
- Center for Diabetes and Metabolic Diseases, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Decio L. Eizirik
- ULB Center for Diabetes Research, Medical Faculty, Université Libre de Bruxelles, Brussels, Belgium
| | - Thomas O. Metz
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
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26
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Purcell AW, Sechi S, DiLorenzo TP. The Evolving Landscape of Autoantigen Discovery and Characterization in Type 1 Diabetes. Diabetes 2019; 68:879-886. [PMID: 31010879 PMCID: PMC6477901 DOI: 10.2337/dbi18-0066] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 01/29/2019] [Indexed: 12/20/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that is caused, in part, by T cell-mediated destruction of insulin-producing β-cells. High risk for disease, in those with genetic susceptibility, is predicted by the presence of two or more autoantibodies against insulin, the 65-kDa form of glutamic acid decarboxylase (GAD65), insulinoma-associated protein 2 (IA-2), and zinc transporter 8 (ZnT8). Despite this knowledge, we still do not know what leads to the breakdown of tolerance to these autoantigens, and we have an incomplete understanding of T1D etiology and pathophysiology. Several new autoantibodies have recently been discovered using innovative technologies, but neither their potential utility in monitoring disease development and treatment nor their role in the pathophysiology and etiology of T1D has been explored. Moreover, neoantigen generation (through posttranslational modification, the formation of hybrid peptides containing two distinct regions of an antigen or antigens, alternative open reading frame usage, and translation of RNA splicing variants) has been reported, and autoreactive T cells that target these neoantigens have been identified. Collectively, these new studies provide a conceptual framework to understand the breakdown of self-tolerance, if such modifications occur in a tissue- or disease-specific context. A recent workshop sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases brought together investigators who are using new methods and technologies to identify autoantigens and characterize immune responses toward these proteins. Researchers with diverse expertise shared ideas and identified resources to accelerate antigen discovery and the detection of autoimmune responses in T1D. The application of this knowledge will direct strategies for the identification of improved biomarkers for disease progression and treatment response monitoring and, ultimately, will form the foundation for novel antigen-specific therapeutics. This Perspective highlights the key issues that were addressed at the workshop and identifies areas for future investigation.
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Affiliation(s)
- Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Salvatore Sechi
- Division of Diabetes, Endocrinology, and Metabolic Diseases, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Teresa P DiLorenzo
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY
- Division of Endocrinology, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY
- Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY
- Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY
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27
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Bioluminescent reporter assay for monitoring ER stress in human beta cells. Sci Rep 2018; 8:17738. [PMID: 30532033 PMCID: PMC6288136 DOI: 10.1038/s41598-018-36142-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 11/13/2018] [Indexed: 12/17/2022] Open
Abstract
During type 1 diabetes development, cells in the islets of Langerhans engage adaptive mechanisms in response to inflammatory signals to cope with stress, to restore cellular homeostasis, and to preserve cell function. Disruption of these mechanisms may induce the formation of a repertoire of stress-induced neoantigens, which are critical in the loss of tolerance to beta cells and the development of autoimmunity. While multiple lines of evidence argue for a critical role of the endoplasmic reticulum in these processes, the lack of tools to specifically monitor beta cell stress hampers the development of therapeutic interventions focusing on maintaining endoplasmic reticulum homeostasis. Here we designed and evaluated a stress-induced reporter in which induction of stress correlates with increased light emission. This Gaussia luciferase-based reporter system employs the unconventional cytoplasmic splicing of XBP1 to report ER stress in cells exposed to known ER-stress inducers. Linking this reporter to a human beta cell-specific promotor allows tracing ER-stress in isolated human beta cells as well as in the EndoC-βH1 cell line. This reporter system represents a valuable tool to assess ER stress in human beta cells and may aid the identification of novel therapeutics that can prevent beta cell stress in human pancreatic islets.
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28
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Yang ML, Doyle HA, Clarke SG, Herold KC, Mamula MJ. Oxidative Modifications in Tissue Pathology and Autoimmune Disease. Antioxid Redox Signal 2018; 29:1415-1431. [PMID: 29088923 PMCID: PMC6166690 DOI: 10.1089/ars.2017.7382] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Various autoimmune syndromes are characterized by abnormalities found at the level of tissues and cells, as well as by microenvironmental influences, such as reactive oxygen species (ROS), that alter intracellular metabolism and protein expression. Moreover, the convergence of genetic, epigenetic, and even environmental influences can result in B and T lymphocyte autoimmunity and tissue pathology. Recent Advances: This review describes how oxidative stress to cells and tissues may alter post-translational protein modifications, both directly and indirectly, as well as potentially lead to aberrant gene expression. For example, it has been clearly observed in many systems how oxidative stress directly amplifies carbonyl protein modifications. However, ROS also lead to a number of nonenzymatic spontaneous modifications including deamidation and isoaspartate modification as well as to enzyme-mediated citrullination of self-proteins. ROS have direct effects on DNA methylation, leading to influences in gene expression, chromosome inactivation, and the silencing of genetic elements. Finally, ROS can alter many other cellular pathways, including the initiation of apoptosis and NETosis, triggering the release of modified intracellular autoantigens. CRITICAL ISSUES This review will detail specific post-translational protein modifications, the pathways that control autoimmunity to modified self-proteins, and how products of ROS may be important biomarkers of tissue pathogenesis. FUTURE DIRECTIONS A clear understanding of the many pathways affected by ROS will lead to potential therapeutic manipulations to alter the onset and/or progression of autoimmune disease.
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Affiliation(s)
- Mei-Ling Yang
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
| | - Hester A Doyle
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
| | - Steven G Clarke
- 3 Department of Chemistry and Biochemistry, University of California , Los Angeles, Los Angeles, California
| | - Kevan C Herold
- 2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut.,4 Department of Immunobiology, Yale University School of Medicine , New Haven, Connecticut
| | - Mark J Mamula
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
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29
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Thomaidou S, Zaldumbide A, Roep BO. Islet stress, degradation and autoimmunity. Diabetes Obes Metab 2018; 20 Suppl 2:88-94. [PMID: 30230178 PMCID: PMC6174957 DOI: 10.1111/dom.13387] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/18/2018] [Accepted: 05/30/2018] [Indexed: 12/15/2022]
Abstract
β-cell destruction in type 1 diabetes (T1D) results from the effect of inflammation and autoimmunity. In response to inflammatory signals, islet cells engage adaptive mechanisms to restore and maintain cellular homeostasis. Among these mechanisms, the unfolded protein response (UPR) leads to a reduction of the general protein translation rate, increased production of endoplasmic reticulum chaperones and the initiation of degradation by activation of the ER associated degradation pathway (ERAD) in which newly synthetized proteins are ubiquitinylated and processed through the proteasome. This adaptive phase is also believed to play a critical role in the development of autoimmunity by the generation of neoantigens. While we have previously investigated the effect of stress on transcription, translation and post-translational events as possible source for neoantigens, the participation of the degradation machinery, yet crucial in the generation of antigenic peptides, remains to be investigated in the context of T1D pathology. In this review, we will describe the relation between the unfolded protein response and the Ubiquitin Proteasome System (UPS) and address the role of the cellular degradation machinery in the generation of antigens. Learning from tumour immunology, we propose how these processes may unmask β-cells by triggering the generation of aberrant peptides recognized by the immune cells.
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Affiliation(s)
- Sofia Thomaidou
- Department of Cell and Chemical BiologyLeiden University Medical CenterLeidenThe Netherlands
| | - Arnaud Zaldumbide
- Department of Cell and Chemical BiologyLeiden University Medical CenterLeidenThe Netherlands
| | - Bart O. Roep
- Department of Immunohematology and Blood bank Leiden University Medical CenterLeiden University Medical CenterLeidenThe Netherlands
- Department of Diabetes ImmunologyDiabetes & Metabolism Research Institute at the Beckman Research InstituteDuarteCalifornia
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30
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Clark M, Kroger CJ, Tisch RM. Type 1 Diabetes: A Chronic Anti-Self-Inflammatory Response. Front Immunol 2017; 8:1898. [PMID: 29312356 PMCID: PMC5743904 DOI: 10.3389/fimmu.2017.01898] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/12/2017] [Indexed: 12/16/2022] Open
Abstract
Inflammation is typically induced in response to a microbial infection. The release of proinflammatory cytokines enhances the stimulatory capacity of antigen-presenting cells, as well as recruits adaptive and innate immune effectors to the site of infection. Once the microbe is cleared, inflammation is resolved by various mechanisms to avoid unnecessary tissue damage. Autoimmunity arises when aberrant immune responses target self-tissues causing inflammation. In type 1 diabetes (T1D), T cells attack the insulin producing β cells in the pancreatic islets. Genetic and environmental factors increase T1D risk by in part altering central and peripheral tolerance inducing events. This results in the development and expansion of β cell-specific effector T cells (Teff) which mediate islet inflammation. Unlike protective immunity where inflammation is terminated, autoimmunity is sustained by chronic inflammation. In this review, we will highlight the key events which initiate and sustain T cell-driven pancreatic islet inflammation in nonobese diabetic mice and in human T1D. Specifically, we will discuss: (i) dysregulation of thymic selection events, (ii) the role of intrinsic and extrinsic factors that enhance the expansion and pathogenicity of Teff, (iii) defects which impair homeostasis and suppressor activity of FoxP3-expressing regulatory T cells, and (iv) properties of β cells which contribute to islet inflammation.
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Affiliation(s)
- Matthew Clark
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Charles J Kroger
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Roland M Tisch
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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31
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Abstract
PURPOSE OF REVIEW By necessity, the vast majority of information we have on autoreactive T cells in human type 1 diabetes (T1D) has come from the study of peripheral blood of donors with T1D. It is not clear how representative the peripheral autoreactive T-cell repertoire is of the autoreactive T cells infiltrating the islets in T1D. We will summarize and discuss what is known of the immunohistopathology of insulitis, the T-cell receptor repertoire expressed by islet-infiltrating T cells, and the autoreactivity and function of islet-infiltrating T cells in T1D. RECENT FINDINGS Recovery and analysis of live, islet-infiltrating T cells from the islets of cadaveric donors with T1D revealed a broad repertoire and proinflammatory phenotype of CD4 T-cell autoreactivity to peptide targets from islet proteins, including proinsulin, as well as CD4 T-cell reactivity to a number of post-translationally modified peptides, including peptides with citrullinations and hybrid insulin peptide fusions. Islet-infiltrating CD8 T cells were also derived and required further isolation and characterization. SUMMARY The recovery of live, islet-infiltrating T cells from donors with T1D, reactive with a broad range of known targets and post-translationally modified peptides, allows for the specific functional analysis of islet-infiltrating T cells for the development of antigen-specific immunotherapies.
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Affiliation(s)
- Sally C Kent
- Division of Diabetes, Department of Medicine, Diabetes Center of Excellence, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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32
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Autoimmunity against a defective ribosomal insulin gene product in type 1 diabetes. Nat Med 2017; 23:501-507. [PMID: 28263308 DOI: 10.1038/nm.4289] [Citation(s) in RCA: 166] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/23/2017] [Indexed: 02/08/2023]
Abstract
Identification of epitopes that are recognized by diabetogenic T cells and cause selective beta cell destruction in type 1 diabetes (T1D) has focused on peptides originating from native beta cell proteins. Translational errors represent a major potential source of antigenic peptides to which central immune tolerance is lacking. Here, we describe an alternative open reading frame within human insulin mRNA encoding a highly immunogenic polypeptide that is targeted by T cells in T1D patients. We show that cytotoxic T cells directed against the N-terminal peptide of this nonconventional product are present in the circulation of individuals diagnosed with T1D, and we provide direct evidence that such CD8+ T cells are capable of killing human beta cells and thereby may be diabetogenic. This study reveals a new source of nonconventional polypeptides that act as self-epitopes in clinical autoimmune disease.
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33
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Analysis of self-antigen specificity of islet-infiltrating T cells from human donors with type 1 diabetes. Nat Med 2016; 22:1482-1487. [PMID: 27798614 DOI: 10.1038/nm.4203] [Citation(s) in RCA: 224] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 09/14/2016] [Indexed: 12/13/2022]
Abstract
A major therapeutic goal for type 1 diabetes (T1D) is to induce autoantigen-specific tolerance of T cells. This could suppress autoimmunity in those at risk for the development of T1D, as well as in those with established disease who receive islet replacement or regeneration therapy. Because functional studies of human autoreactive T cell responses have been limited largely to peripheral blood-derived T cells, it is unclear how representative the peripheral T cell repertoire is of T cells infiltrating the islets. Our knowledge of the insulitic T cell repertoire is derived from histological and immunohistochemical analyses of insulitis, the identification of autoreactive CD8+ T cells in situ, in islets of human leukocyte antigen (HLA)-A2+ donors and isolation and identification of DQ8 and DQ2-DQ8 heterodimer-restricted, proinsulin-reactive CD4+ T cells grown from islets of a single donor with T1D. Here we present an analysis of 50 of a total of 236 CD4+ and CD8+ T cell lines grown from individual handpicked islets or clones directly sorted from handpicked, dispersed islets from nine donors with T1D. Seventeen of these T cell lines and clones reacted to a broad range of studied native islet antigens and to post-translationally modified peptides. These studies demonstrate the existence of a variety of islet-infiltrating, islet-autoantigen reactive T cells in individuals with T1D, and these data have implications for the design of successful immunotherapies.
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34
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An insulin-IAPP hybrid peptide is an endogenous antigen for CD4 T cells in the non-obese diabetic mouse. J Autoimmun 2016; 78:11-18. [PMID: 27802879 DOI: 10.1016/j.jaut.2016.10.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 10/19/2016] [Accepted: 10/20/2016] [Indexed: 12/28/2022]
Abstract
BDC-6.9, a diabetogenic CD4 T cell clone isolated from a non-obese diabetic (NOD) mouse, responds to pancreatic islet cells from NOD but not BALB/c mice. We recently reported that a hybrid insulin peptide (HIP), 6.9HIP, formed by linkage of an insulin C-peptide fragment and a fragment of islet amyloid polypeptide (IAPP), is the antigen for BDC-6.9. We report here that the core 12-mer peptide from 6.9HIP, centered on the hybrid peptide junction, is also highly antigenic for BDC-6.9. In agreement with the observation that BALB/c islet cells fail to stimulate the T cell clone, a single amino acid difference in the BALB/c IAPP sequence renders the BALB/c version of the HIP only weakly antigenic. Mutant peptide analysis indicates that each parent molecule-insulin C-peptide and IAPP-donates residues critical for antigenicity. Through mass spectrometric analysis, we determine the distribution of naturally occurring 6.9HIP across chromatographic fractions of proteins from pancreatic beta cells. This distribution closely matches the profile of the T cell response to the fractions, confirming that 6.9HIP is the endogenous islet antigen for the clone. Using a new MHC II tetramer reagent, 6.9HIP-tet, we show that T cells specific for the 6.9HIP peptide are prevalent in the pancreas of diabetic NOD mice. Further study of HIPs and HIP-reactive T cells could yield valuable insight into key factors driving progression to diabetes and thereby inform efforts to prevent or reverse this disease.
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35
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Roep BO, Kracht MJ, van Lummel M, Zaldumbide A. A roadmap of the generation of neoantigens as targets of the immune system in type 1 diabetes. Curr Opin Immunol 2016; 43:67-73. [PMID: 27723537 DOI: 10.1016/j.coi.2016.09.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/16/2016] [Accepted: 09/28/2016] [Indexed: 01/08/2023]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of the insulin-producing beta cells. Beta cell dysfunction caused by an inflammatory microenvironment is believed to trigger the peripheral activation of CD4 and CD8 autoreactive T cells. This review will compile post-transcriptional and post-translational modifications (PTM) involved in the generation of beta cell neoantigens and proposes a reconstruction of the sequence of events connecting environmental changes and autoimmunity.
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Affiliation(s)
- Bart O Roep
- Department of Diabetes Immunology, Diabetes and Metabolism Research Institute at the Beckman Research Institute of the City of Hope, Duarte, CA, USA; Department of Immunohematology & Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.
| | - Maria Jl Kracht
- Department of Immunohematology & Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands; Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Menno van Lummel
- Department of Immunohematology & Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Arnaud Zaldumbide
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
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36
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McLaughlin RJ, Spindler MP, van Lummel M, Roep BO. Where, How, and When: Positioning Posttranslational Modification Within Type 1 Diabetes Pathogenesis. Curr Diab Rep 2016; 16:63. [PMID: 27168063 PMCID: PMC4863913 DOI: 10.1007/s11892-016-0752-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Autoreactive T cells specific for islet autoantigens develop in type 1 diabetes (T1D) by escaping central as well as peripheral tolerance. The current paradigm for development of islet autoimmunity is just beginning to include the contribution of posttranslationally modified (PTM) islet autoantigens, for which the immune system may be ignorant rather than tolerant. As a result, PTM is the latest promising lead in the quest to understand how the break in peripheral tolerance occurs in T1D. However, it is not completely clear how, where, or when these modifications take place. Currently, only a few PTM antigens have been well-thought-out or identified in T1D, and methods for identifying and characterizing new PTM antigens are rapidly improving. This review will address both reported and potential new sources of modified islet autoantigens and discuss how islet neo-autoantigen generation may contribute to the development and progression of T1D.
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Affiliation(s)
- Rene J McLaughlin
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, E3-Q, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | - Matthew P Spindler
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, E3-Q, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | - Menno van Lummel
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, E3-Q, PO Box 9600, 2300 RC, Leiden, The Netherlands
| | - Bart O Roep
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, E3-Q, PO Box 9600, 2300 RC, Leiden, The Netherlands.
- Department of Diabetes Immunology, Diabetes & Metabolism Research Institute, Beckman Research Institute of City of Hope, Duarte, CA, 91010, USA.
- Danish Diabetes Academy, Søndre Blvd. 29, 5000, Odense, Denmark.
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37
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Kracht MJL, Zaldumbide A, Roep BO. Neoantigens and Microenvironment in Type 1 Diabetes: Lessons from Antitumor Immunity. Trends Endocrinol Metab 2016; 27:353-362. [PMID: 27094501 DOI: 10.1016/j.tem.2016.03.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 03/15/2016] [Accepted: 03/20/2016] [Indexed: 12/24/2022]
Abstract
Type 1 diabetes (T1D) is characterized by the selective and progressive destruction of insulin-producing beta cells by the immune system. An incomplete thymic selection against self-reactive islet antigens partly explains how these T cells reach the periphery and become diabetogenic. Increasing evidence suggest that beta cells themselves also participate to their own demise by generating neoepitopes that could be recognized by the immune surveillance machinery. In this regard, these T cells eradicate self-tissue by mechanisms analogous to a classical antitumor response. Cancer immunotherapy has exploited mutations and transcriptional and translational errors to trigger a specific antitumor response. In this opinion article, we aim at merging insight in antitumor immunology and autoimmunity to reveal processes that had previously been ignored to create beta cell-specific neoantigens.
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Affiliation(s)
- Maria J L Kracht
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands; Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Arnaud Zaldumbide
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Bart O Roep
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands; Department of Diabetes Immunology, Diabetes and Metabolism Research Institute at the Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.
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