1
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Kennedy EC, Hawkes CP. Approaches to Measuring Beta Cell Reserve and Defining Partial Clinical Remission in Paediatric Type 1 Diabetes. CHILDREN (BASEL, SWITZERLAND) 2024; 11:186. [PMID: 38397298 PMCID: PMC10887271 DOI: 10.3390/children11020186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/26/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024]
Abstract
CONTEXT Type 1 diabetes (T1D) results from the autoimmune T-cell mediated destruction of pancreatic beta cells leading to insufficient insulin secretion. At the time of diagnosis of T1D, there is residual beta cell function that declines over the subsequent months to years. Recent interventions have been approved to preserve beta cell function in evolving T1D. OBJECTIVE The aim of this review is to summarise the approaches used to assess residual beta cell function in evolving T1D, and to highlight potential future directions. METHODS Studies including subjects aged 0 to 18 years were included in this review. The following search terms were used; "(type 1 diabetes) and (partial remission)" and "(type 1 diabetes) and (honeymoon)". References of included studies were reviewed to determine if additional relevant studies were eligible. RESULTS There are numerous approaches to quantifying beta cell reserve in evolving T1D. These include c-peptide measurement after a mixed meal or glucagon stimuli, fasting c-peptide, the urinary c-peptide/creatinine ratio, insulin dose-adjusted haemoglobin A1c, and other clinical models to estimate beta cell function. Other biomarkers may have a role, including the proinsulin/c-peptide ratio, cytokines, and microRNA. Studies using thresholds to determine if residual beta cell function is present often differ in values used to define remission. CONCLUSIONS As interventions are approved to preserve beta cell function, it will become increasingly necessary to quantify residual beta cell function in research and clinical contexts. In this report, we have highlighted the strengths and limitations of the current approaches.
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Affiliation(s)
- Elaine C Kennedy
- Department of Paediatrics and Child Health, University College Cork, T12 DC4A Cork, Ireland
- INFANT Research Centre, University College Cork, T12 DC4A Cork, Ireland
| | - Colin P Hawkes
- Department of Paediatrics and Child Health, University College Cork, T12 DC4A Cork, Ireland
- INFANT Research Centre, University College Cork, T12 DC4A Cork, Ireland
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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2
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Gomez-Muñoz L, Dominguez-Bendala J, Pastori RL, Vives-Pi M. Immunometabolic biomarkers for partial remission in type 1 diabetes mellitus. Trends Endocrinol Metab 2024; 35:151-163. [PMID: 37949732 DOI: 10.1016/j.tem.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 11/12/2023]
Abstract
Shortly after diagnosis of type 1 diabetes mellitus (T1DM) and initiation of insulin therapy, many patients experience a transient partial remission (PR) phase, also known as the honeymoon phase. This phase presents a potential therapeutic opportunity due to its association with immunoregulatory and β cell-protective mechanisms. However, the lack of biomarkers makes its characterization difficult. In this review, we cover the current literature addressing the discovery of new predictive and monitoring biomarkers that contribute to the understanding of the metabolic, epigenetic, and immunological mechanisms underlying PR. We further discuss how these peripheral biomarkers reflect attempts to arrest β cell autoimmunity and how these can be applied in clinical practice.
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Affiliation(s)
- Laia Gomez-Muñoz
- Immunology Section, Germans Trias i Pujol Research Institute, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Juan Dominguez-Bendala
- Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Ricardo L Pastori
- Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Marta Vives-Pi
- Immunology Section, Germans Trias i Pujol Research Institute, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; Ahead Therapeutics SL, 08193, Bellaterra, Barcelona, Spain.
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3
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Anindya R, Rutter GA, Meur G. New-onset type 1 diabetes and severe acute respiratory syndrome coronavirus 2 infection. Immunol Cell Biol 2023; 101:191-203. [PMID: 36529987 PMCID: PMC9877852 DOI: 10.1111/imcb.12615] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/09/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Type 1 diabetes (T1D) is a condition characterized by an absolute deficiency of insulin. Loss of insulin-producing pancreatic islet β cells is one of the many causes of T1D. Viral infections have long been associated with new-onset T1D and the balance between virulence and host immunity determines whether the viral infection would lead to T1D. Herein, we detail the dynamic interaction of pancreatic β cells with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the host immune system with respect to new-onset T1D. Importantly, β cells express the crucial entry receptors and multiple studies confirmed that β cells are infected by SARS-CoV-2. Innate immune system effectors, such as natural killer cells, can eliminate such infected β cells. Although CD4+ CD25+ FoxP3+ regulatory T (TREG ) cells provide immune tolerance to prevent the destruction of the islet β-cell population by autoantigen-specific CD8+ T cells, it can be speculated that SARS-CoV-2 infection may compromise self-tolerance by depleting TREG -cell numbers or diminishing TREG -cell functions by repressing Forkhead box P3 (FoxP3) expression. However, the expansion of β cells by self-duplication, and regeneration from progenitor cells, could effectively replace lost β cells. Appearance of islet autoantibodies following SARS-CoV-2 infection was reported in a few cases, which could imply a breakdown of immune tolerance in the pancreatic islets. However, many of the cases with newly diagnosed autoimmune response following SARS-CoV-2 infection also presented with significantly high HbA1c (glycated hemoglobin) levels that indicated progression of an already set diabetes, rather than new-onset T1D. Here we review the potential underlying mechanisms behind loss of functional β-cell mass as a result of SARS-CoV-2 infection that can trigger new-onset T1D.
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Affiliation(s)
- Roy Anindya
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Sangareddy, Telangana, India
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore City, Singapore.,Centre of Research of Centre Hospitalier de l'Université de Montréal (CRCHUM), Faculty of Medicine, University of Montréal, Montréal, QC, Canada
| | - Gargi Meur
- ICMR-National Institute of Nutrition, Hyderabad, Telangana, India
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4
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Marshall G, Cserny J, Wang CW, Looney B, Posgai AL, Bacher R, Keselowsky B, Brusko TM. Biomaterials-based nanoparticles conjugated to regulatory T cells provide a modular system for localized delivery of pharmacotherapeutic agents. J Biomed Mater Res A 2023; 111:185-197. [PMID: 36082558 PMCID: PMC9742177 DOI: 10.1002/jbm.a.37442] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/11/2022] [Accepted: 08/15/2022] [Indexed: 12/14/2022]
Abstract
Type 1 diabetes (T1D) presents with two therapeutic challenges: the need to correct underlying autoimmunity and restore β-cell mass. We harnessed the unique capacity of regulatory T cells (Tregs) and the T cell receptor (TCR) to direct tolerance induction along with tissue-localized delivery of therapeutic agents to restore endogenous β-cell function. Specifically, we designed a combinatorial therapy involving biomaterials-based poly(lactic-co-glycolic acid) nanoparticles co-loaded with the Treg growth factor, IL-2, and the β-cell regenerative agent, harmine (a tyrosine-regulated kinase 1A [DYRK1A] inhibitor), conjugated to the surface of Tregs. We observed continuous elution of IL-2 and harmine from nanoparticles for at least 7 days in vitro. When conjugated to primary human Tregs, IL-2 nanoparticles provided sufficient IL-2 receptor signaling to support STAT5 phosphorylation for sustained phenotypic stability and viability in culture. Inclusion of poly-L-lysine (PLL) during nanoparticle-cell coupling dramatically increased conjugation efficiency, providing sufficient IL-2 to support in vitro proliferation of IL-2-dependent CTLL-2 cells and primary murine Tregs. In 12-week-old female non-obese diabetic mice, adoptive transfer of IL-2/harmine nanoparticle-conjugated NOD.BDC2.5 Tregs, which express an islet antigen-specific TCR, significantly prevented diabetes demonstrating preserved in vivo viability. These data provide the preclinical basis to develop a biomaterials-optimized cellular therapy to restore immune tolerance and promote β-cell proliferation in T1D through receptor-targeted drug delivery within pancreatic islets.
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Affiliation(s)
| | - Judit Cserny
- Department of Pathology, Immunology and Laboratory Medicine, Diabetes Institute, College of Medicine, University of Florida, Gainesville, FL 32601, USA
| | | | | | - Amanda L. Posgai
- Department of Pathology, Immunology and Laboratory Medicine, Diabetes Institute, College of Medicine, University of Florida, Gainesville, FL 32601, USA
| | - Rhonda Bacher
- Department of Biostatistics, College of Public Health and Health Professions, and College of Medicine, University of Florida, Gainesville, FL
| | - Benjamin Keselowsky
- J. Crayton Pruitt Family Department of Biomedical Engineering, College of Engineering, University of Florida, Gainesville, FL 32601, USA
| | - Todd M. Brusko
- Inspira Therapeutics, Inc., Alachua, FL 32615, USA,Department of Pathology, Immunology and Laboratory Medicine, Diabetes Institute, College of Medicine, University of Florida, Gainesville, FL 32601, USA,Department of Pediatrics, Diabetes Institute, College of Medicine, University of Florida, Gainesville, FL 32601, USA,Correspondence to: Todd M. Brusko, PhD, Department of Pathology, University of Florida, College of Medicine, Box 100275, 1600 SW Archer Road, Gainesville, FL 32610; (352) 273-9255; Fax (352) 273-9339;
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5
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Gomez-Muñoz L, Perna-Barrull D, Caroz-Armayones JM, Murillo M, Rodriguez-Fernandez S, Valls A, Vazquez F, Perez J, Corripio R, Castaño L, Bel J, Vives-Pi M. Candidate Biomarkers for the Prediction and Monitoring of Partial Remission in Pediatric Type 1 Diabetes. Front Immunol 2022; 13:825426. [PMID: 35280980 PMCID: PMC8904370 DOI: 10.3389/fimmu.2022.825426] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/31/2022] [Indexed: 01/10/2023] Open
Abstract
The partial remission (PR) phase, a period experienced by most patients with type 1 diabetes (T1D) soon after diagnosis, is characterized by low insulin requirements and improved glycemic control. Given the great potential of this phase as a therapeutic window for immunotherapies because of its association with immunoregulatory mechanisms and β-cell protection, our objective was to find peripheral immunological biomarkers for its better characterization, monitoring, and prediction. The longitudinal follow-up of 17 pediatric patients with new-onset T1D over one year revealed that, during the PR phase, remitter patients show increased percentages of effector memory (EM) T lymphocytes, terminally differentiated EM T lymphocytes, and neutrophils in comparison to non-remitter patients. On the contrary, remitter patients showed lower percentages of naïve T lymphocytes, regulatory T cells (TREG), and dendritic cells (DCs). After a year of follow-up, these patients also presented increased levels of regulatory B cells and transitional T1 B lymphocytes. On the other hand, although none of the analyzed cytokines (IL-2, IL-6, TGF-β1, IL-17A, and IL-10) could distinguish or predict remission, IL-17A was increased at T1D diagnosis in comparison to control subjects, and remitter patients tended to maintain lower levels of this cytokine than non-remitters. Therefore, these potential monitoring immunological biomarkers of PR support that this stage is governed by both metabolic and immunological factors and suggest immunoregulatory attempts during this phase. Furthermore, since the percentage of TREG, monocytes, and DCs, and the total daily insulin dose at diagnosis were found to be predictors of the PR phase, we next created an index-based predictive model comprising those immune cell percentages that could potentially predict remission at T1D onset. Although our preliminary study needs further validation, these candidate biomarkers could be useful for the immunological characterization of the PR phase, the stratification of patients with better disease prognosis, and a more personalized therapeutic management.
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Affiliation(s)
- Laia Gomez-Muñoz
- Immunology Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - David Perna-Barrull
- Immunology Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Josep M. Caroz-Armayones
- Department of Political and Social Sciences, Health Inequalities Research Group (GREDS-EMCONET), Pompeu Fabra University, Barcelona, Spain
- Johns Hopkins University–Pompeu Fabra University Public Policy Center, Barcelona, Spain
| | - Marta Murillo
- Pediatrics Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Silvia Rodriguez-Fernandez
- Immunology Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Aina Valls
- Pediatrics Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Federico Vazquez
- Endocrinology Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Jacobo Perez
- Pediatric Endocrinology Department, Parc Taulí Hospital Universitari, Institut d’Investigació i Innovació Parc Taulí I3PT, Autonomous University of Barcelona, Sabadell, Spain
| | - Raquel Corripio
- Pediatric Endocrinology Department, Parc Taulí Hospital Universitari, Institut d’Investigació i Innovació Parc Taulí I3PT, Autonomous University of Barcelona, Sabadell, Spain
| | - Luis Castaño
- Cruces University Hospital, Biocruces Bizkaia Research Institute, UPV/EHU, CIBERDEM, CIBERER, Endo-ERN, Bilbao, Spain
| | - Joan Bel
- Pediatrics Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
| | - Marta Vives-Pi
- Immunology Department, Germans Trias i Pujol Research Institute and University Hospital, Autonomous University of Barcelona, Badalona, Spain
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6
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Arjomandnejad M, Kopec AL, Keeler AM. CAR-T Regulatory (CAR-Treg) Cells: Engineering and Applications. Biomedicines 2022; 10:287. [PMID: 35203496 PMCID: PMC8869296 DOI: 10.3390/biomedicines10020287] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/21/2022] [Accepted: 01/24/2022] [Indexed: 01/27/2023] Open
Abstract
Regulatory T cells are critical for maintaining immune tolerance. Recent studies have confirmed their therapeutic suppressive potential to modulate immune responses in organ transplant and autoimmune diseases. However, the unknown and nonspecific antigen recognition of polyclonal Tregs has impaired their therapeutic potency in initial clinical findings. To address this limitation, antigen specificity can be conferred to Tregs by engineering the expression of transgenic T-cell receptor (TCR) or chimeric antigen receptor (CAR). In contrast to TCR Tregs, CAR Tregs are major histocompatibility complex (MHC) independent and less dependent on interleukin-2 (IL-2). Furthermore, CAR Tregs maintain Treg phenotype and function, home to the target tissue and show enhanced suppressive efficacy compared to polyclonal Tregs. Additional development of engineered CAR Tregs is needed to increase Tregs' suppressive function and stability, prevent CAR Treg exhaustion, and assess their safety profile. Further understanding of Tregs therapeutic potential will be necessary before moving to broader clinical applications. Here, we summarize recent studies utilizing CAR Tregs in modulating immune responses in autoimmune diseases, transplantation, and gene therapy and future clinical applications.
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Affiliation(s)
- Motahareh Arjomandnejad
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA; (M.A.); (A.L.K.)
| | - Acadia L. Kopec
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA; (M.A.); (A.L.K.)
| | - Allison M. Keeler
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA; (M.A.); (A.L.K.)
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
- NeuroNexus Institute, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
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7
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Ben-Skowronek I, Sieniawska J, Pach E, Wrobel W, Skowronek A, Tomczyk Z, Rosolowska I. Potential Therapeutic Application of Regulatory T Cells in Diabetes Mellitus Type 1. Int J Mol Sci 2021; 23:ijms23010390. [PMID: 35008819 PMCID: PMC8745590 DOI: 10.3390/ijms23010390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/18/2021] [Accepted: 12/28/2021] [Indexed: 01/02/2023] Open
Abstract
The autoimmune reaction against the beta cells of the pancreatic islets in type 1 diabetes mellitus (T1DM) patients is active in prediabetes and during the development of the clinical manifestation of T1DM, but it decreases within a few years of the clinical manifestation of this disease. A key role in the pathogenesis of T1DM is played by regulatory T cell (Treg) deficiency or dysfunction. Immune interventions, such as potential therapeutic applications or the induction of the Treg-cell population in T1DM, will be important in the development of new types of treatment. The aim of this study was to evaluate innovative immune interventions as treatments for T1DM. After an evaluation of full-length papers from the PubMed database from 2010 to 2021, 20 trials were included for the final analysis. The analysis led to the following conclusions: Treg cells play an important role in the limitation of the development of T1DM, the activation or application of Tregs may be more effective in the early stages of T1DM development, and the therapeutic use of Treg cells in T1DM is promising but requires long-term observation in a large group of patients.
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8
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Dwyer AJ, Ritz JM, Mitchell JS, Martinov T, Alkhatib M, Silva N, Tucker CG, Fife BT. Enhanced CD4 + and CD8 + T cell infiltrate within convex hull defined pancreatic islet borders as autoimmune diabetes progresses. Sci Rep 2021; 11:17142. [PMID: 34433860 PMCID: PMC8387412 DOI: 10.1038/s41598-021-96327-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 08/03/2021] [Indexed: 11/16/2022] Open
Abstract
The notion that T cell insulitis increases as type 1 diabetes (T1D) develops is unsurprising, however, the quantitative analysis of CD4+ and CD8+ T cells within the islet mass is complex and limited with standard approaches. Optical microscopy is an important and widely used method to evaluate immune cell infiltration into pancreatic islets of Langerhans for the study of disease progression or therapeutic efficacy in murine T1D. However, the accuracy of this approach is often limited by subjective and potentially biased qualitative assessment of immune cell subsets. In addition, attempts at quantitative measurements require significant time for manual analysis and often involve sophisticated and expensive imaging software. In this study, we developed and illustrate here a streamlined analytical strategy for the rapid, automated and unbiased investigation of islet area and immune cell infiltration within (insulitis) and around (peri-insulitis) pancreatic islets. To this end, we demonstrate swift and accurate detection of islet borders by modeling cross-sectional islet areas with convex polygons (convex hulls) surrounding islet-associated insulin-producing β cell and glucagon-producing α cell fluorescent signals. To accomplish this, we used a macro produced with the freeware software ImageJ equipped with the Fiji Is Just ImageJ (FIJI) image processing package. Our image analysis procedure allows for direct quantification and statistical determination of islet area and infiltration in a reproducible manner, with location-specific data that more accurately reflect islet areas as insulitis proceeds throughout T1D. Using this approach, we quantified the islet area infiltrated with CD4+ and CD8+ T cells allowing statistical comparison between different age groups of non-obese diabetic (NOD) mice progressing towards T1D. We found significantly more CD4+ and CD8+ T cells infiltrating the convex hull-defined islet mass of 13-week-old non-diabetic and 17-week-old diabetic NOD mice compared to 4-week-old NOD mice. We also determined a significant and measurable loss of islet mass in mice that developed T1D. This approach will be helpful for the location-dependent quantitative calculation of islet mass and cellular infiltration during T1D pathogenesis and can be combined with other markers of inflammation or activation in future studies.
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Affiliation(s)
- Alexander J Dwyer
- Center for Immunology, Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota Medical School, 2101 6th St SE, Wallin Medical Biosciences Building, 3-146, Minneapolis, MN, 55455, USA
| | - Jacob M Ritz
- School of Physics and Astronomy, University of Minnesota, Twin Cities, Minneapolis, MN, USA
| | - Jason S Mitchell
- Center for Immunology, Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Tijana Martinov
- Clinical Research Division, Program in Immunology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Mohannad Alkhatib
- Center for Immunology, Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota Medical School, 2101 6th St SE, Wallin Medical Biosciences Building, 3-146, Minneapolis, MN, 55455, USA
| | - Nubia Silva
- Center for Immunology, Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota Medical School, 2101 6th St SE, Wallin Medical Biosciences Building, 3-146, Minneapolis, MN, 55455, USA
| | - Christopher G Tucker
- Center for Immunology, Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota Medical School, 2101 6th St SE, Wallin Medical Biosciences Building, 3-146, Minneapolis, MN, 55455, USA
| | - Brian T Fife
- Center for Immunology, Department of Medicine, Division of Rheumatic and Autoimmune Diseases, University of Minnesota Medical School, 2101 6th St SE, Wallin Medical Biosciences Building, 3-146, Minneapolis, MN, 55455, USA.
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9
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Narsale A, Lam B, Moya R, Lu T, Mandelli A, Gotuzzo I, Pessina B, Giamporcaro G, Geoffrey R, Buchanan K, Harris M, Bergot AS, Thomas R, Hessner MJ, Battaglia M, Serti E, Davies JD. CD4+CD25+CD127hi cell frequency predicts disease progression in type 1 diabetes. JCI Insight 2021; 6:136114. [PMID: 33301420 PMCID: PMC7934872 DOI: 10.1172/jci.insight.136114] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 12/02/2020] [Indexed: 12/16/2022] Open
Abstract
Transient partial remission, a period of low insulin requirement experienced by most patients soon after diagnosis, has been associated with mechanisms of immune regulation. A better understanding of such natural mechanisms of immune regulation might identify new targets for immunotherapies that reverse type 1 diabetes (T1D). In this study, using Cox model multivariate analysis, we validated our previous findings that patients with the highest frequency of CD4+CD25+CD127hi (127-hi) cells at diagnosis experience the longest partial remission, and we showed that the 127-hi cell population is a mix of Th1- and Th2-type cells, with a significant bias toward antiinflammatory Th2-type cells. In addition, we extended these findings to show that patients with the highest frequency of 127-hi cells at diagnosis were significantly more likely to maintain β cell function. Moreover, in patients treated with alefacept in the T1DAL clinical trial, the probability of responding favorably to the antiinflammatory drug was significantly higher in those with a higher frequency of 127-hi cells at diagnosis than those with a lower 127-hi cell frequency. These data are consistent with the hypothesis that 127-hi cells maintain an antiinflammatory environment that is permissive for partial remission, β cell survival, and response to antiinflammatory immunotherapy.
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Affiliation(s)
- Aditi Narsale
- San Diego Biomedical Research Institute, San Diego, California, USA
| | - Breanna Lam
- San Diego Biomedical Research Institute, San Diego, California, USA
| | - Rosa Moya
- San Diego Biomedical Research Institute, San Diego, California, USA
| | - TingTing Lu
- Immune Tolerance Network, Bethesda, Maryland, USA
| | - Alessandra Mandelli
- San Raffaele Diabetes Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Hospital, Milan, Italy
| | - Irene Gotuzzo
- San Raffaele Diabetes Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Hospital, Milan, Italy
| | - Benedetta Pessina
- San Raffaele Diabetes Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Hospital, Milan, Italy
| | - Gianmaria Giamporcaro
- San Raffaele Diabetes Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Hospital, Milan, Italy
| | - Rhonda Geoffrey
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Kerry Buchanan
- Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia.,Department of Pediatric Endocrinology, Queensland Children's Hospital, South Brisbane, Queensland, Australia
| | - Mark Harris
- Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia.,Department of Pediatric Endocrinology, Queensland Children's Hospital, South Brisbane, Queensland, Australia
| | - Anne-Sophie Bergot
- Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Ranjeny Thomas
- Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Martin J Hessner
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Manuela Battaglia
- San Raffaele Diabetes Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Hospital, Milan, Italy
| | | | - Joanna D Davies
- San Diego Biomedical Research Institute, San Diego, California, USA
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10
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Zhong T, Tang R, Gong S, Li J, Li X, Zhou Z. The remission phase in type 1 diabetes: Changing epidemiology, definitions, and emerging immuno-metabolic mechanisms. Diabetes Metab Res Rev 2020; 36:e3207. [PMID: 31343814 DOI: 10.1002/dmrr.3207] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 07/15/2019] [Accepted: 07/18/2019] [Indexed: 12/18/2022]
Abstract
Type 1 diabetes mellitus (T1DM) is characterized by irreversible islet β cell destruction. During the progression of this disease, some patients with T1DM experience a phase of remission known as honeymoon or partial remission (PR) that is mainly characterized by satisfactory glycemic control and the transient recovery of islet β cell function. This special phase is a good model for studying the mechanism of β cell protection, might serve as a proper intervention period for immunotherapy, and may be related to disease prognosis. This special stage is highly valuable for studies aiming to identify possible targets that may be used to cure T1DM. An in-depth understanding of the diagnosis, epidemiology, and possible mechanisms of the PR phase is highly needed. In general, patients enter the PR phase approximately 3 months after starting insulin therapy, and this phase could be sustained for 6 to 9 months. Current research increasingly focuses on the metabolic and immunological aspects to constantly update our understanding of this phase. This review concentrates on the PR phase of T1DM to provide a comprehensive outlook of its epidemiology, diagnostic criteria, and underlying immune metabolic mechanisms.
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Affiliation(s)
- Ting Zhong
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
| | - Rong Tang
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
| | - Siyuan Gong
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
| | - Juan Li
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
| | - Xia Li
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
| | - Zhiguang Zhou
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, National Clinical Research Center for Metabolic Disease, Changsha, China
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11
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Grohová A, Dáňová K, Špíšek R, Palová-Jelínková L. Cell Based Therapy for Type 1 Diabetes: Should We Take Hyperglycemia Into Account? Front Immunol 2019; 10:79. [PMID: 30804929 PMCID: PMC6370671 DOI: 10.3389/fimmu.2019.00079] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/11/2019] [Indexed: 12/16/2022] Open
Abstract
Diabetes mellitus is characterized by long standing hyperglycemia leading to numerous life-threatening complications. For type 1 diabetes mellitus, resulting from selective destruction of insulin producing cells by exaggerated immune reaction, the only effective therapy remains exogenous insulin administration. Despite accurate compliance to treatment of certain patients, transient episodes of hyperglycemia cannot be completely eliminated by this symptomatic treatment. Novel immunotherapeutic approaches based on tolerogenic dendritic cells, T regulatory cells and mesenchymal stem cells (MSCs) have been tested in clinical trials, endeavoring to directly modulate the autoimmune destruction process in pancreas. However, hyperglycemia itself affects the immune system and the final efficacy of cell-based immunotherapies could be affected by the different glycemic control of enrolled patients. The present review explores the impact of hyperglycemia on immune cells while providing greater insight into the molecular mechanisms of high glucose action and subsequent metabolic reprogramming of different immune cells. Furthermore, over-production of mitochondrial reactive oxygen species, formation of advanced glycation end products as a consequence of hyperglycemia and their downstream signalization in immune cells are also discussed. Since hyperglycemia in patients with type 1 diabetes mellitus might have an impact on immune-interventional treatment, the maintenance of a tight glucose control seems to be beneficial in patients considered for cell-based therapy.
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Affiliation(s)
- Anna Grohová
- SOTIO a.s., Prague, Czechia.,Department of Immunology, Second Faculty of Medicine, University Hospital Motol, Charles University in Prague, Prague, Czechia.,Department of Pediatrics, Charles University in Prague, Second Faculty of Medicine, University Hospital Motol, Prague, Czechia
| | - Klára Dáňová
- SOTIO a.s., Prague, Czechia.,Department of Immunology, Second Faculty of Medicine, University Hospital Motol, Charles University in Prague, Prague, Czechia
| | - Radek Špíšek
- SOTIO a.s., Prague, Czechia.,Department of Immunology, Second Faculty of Medicine, University Hospital Motol, Charles University in Prague, Prague, Czechia
| | - Lenka Palová-Jelínková
- SOTIO a.s., Prague, Czechia.,Department of Immunology, Second Faculty of Medicine, University Hospital Motol, Charles University in Prague, Prague, Czechia
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12
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Hull CM, Peakman M, Tree TIM. Regulatory T cell dysfunction in type 1 diabetes: what's broken and how can we fix it? Diabetologia 2017; 60:1839-1850. [PMID: 28770318 PMCID: PMC6448885 DOI: 10.1007/s00125-017-4377-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 05/17/2017] [Indexed: 01/07/2023]
Abstract
Type 1 diabetes is an autoimmune disease characterised by the destruction of insulin producing beta cells in the pancreas. Whilst it remains unclear what the original triggering factors for this destruction are, observations from the natural history of human type 1 diabetes, including incidence rates in twins, suggest that the disease results from a combination of genetic and environmental factors. Whilst many different immune cells have been implicated, including members of the innate and adaptive immune systems, a view has emerged over the past 10 years that beta cell damage is mediated by the combined actions of CD4+ and CD8+ T cells with specificity for islet autoantigens. In health, these potentially pathogenic T cells are held in check by multiple regulatory mechanisms, known collectively as 'immunological tolerance'. This raises the question as to whether type 1 diabetes develops, at least in part, as a result of a defect in one or more of these control mechanisms. Immunological tolerance includes both central mechanisms (purging of the T cell repertoire of high-affinity autoreactive T cells in the thymus) and peripheral mechanisms, a major component of which is the action of a specialised subpopulation of T cells, known as regulatory T cells (Tregs). In this review, we highlight the evidence suggesting that a reduction in the functional capacity of different Treg populations contributes to disease development in type 1 diabetes. We also address current controversies regarding the putative causes of this defect and discuss strategies to correct it as a means to reduce or prevent islet destruction in a clinical setting.
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Affiliation(s)
- Caroline M Hull
- Programme of Infection and Immunity, Department of Immunobiology, Faculty of Life Sciences and Medicine, King's College London, Borough Wing, Guy's Hospital, London, SE1 9RT, UK.
| | - Mark Peakman
- Programme of Infection and Immunity, Department of Immunobiology, Faculty of Life Sciences and Medicine, King's College London, Borough Wing, Guy's Hospital, London, SE1 9RT, UK
- NIHR Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK
| | - Timothy I M Tree
- Programme of Infection and Immunity, Department of Immunobiology, Faculty of Life Sciences and Medicine, King's College London, Borough Wing, Guy's Hospital, London, SE1 9RT, UK.
- NIHR Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK.
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13
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Hull CM, Nickolay LE, Estorninho M, Richardson MW, Riley JL, Peakman M, Maher J, Tree TI. Generation of human islet-specific regulatory T cells by TCR gene transfer. J Autoimmun 2017; 79:63-73. [DOI: 10.1016/j.jaut.2017.01.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 01/12/2017] [Indexed: 01/12/2023]
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14
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Treiber G, Prietl B, Fröhlich-Reiterer E, Lechner E, Ribitsch A, Fritsch M, Rami-Merhar B, Steigleder-Schweiger C, Graninger W, Borkenstein M, Pieber TR. Cholecalciferol supplementation improves suppressive capacity of regulatory T-cells in young patients with new-onset type 1 diabetes mellitus - A randomized clinical trial. Clin Immunol 2015; 161:217-24. [PMID: 26277548 DOI: 10.1016/j.clim.2015.08.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/28/2015] [Accepted: 08/07/2015] [Indexed: 12/14/2022]
Abstract
It is unknown if cholecalciferol is able to modify defects in regulatory T cells (Tregs) in type 1 diabetes (T1D). In this randomized, double-blind, placebo controlled trial 30 young patients with new-onset T1D were assigned to cholecalciferol (70IU/kgbodyweight/day) or placebo for 12months. Tregs were determined by FACS-analysis and functional tests were assessed with ex vivo suppression co-cultures at months 0, 3, 6 and 12. Suppressive capacity of Tregs increased (p<0.001) with cholecalciferol from baseline (-1.59±25.6%) to 3 (30.5±39.4%), 6 (44.6±23.8%) and 12months (37.2±25.0%) and change of suppression capacity from baseline to 12months was significantly higher (p<0.05) with cholecalciferol (22.2±47.2%) than placebo (-16.6±21.1%). Serum calcium and parathormone stayed within normal range. This is the first study, which showed that cholecalciferol improved suppressor function of Tregs in patients with T1D and vitamin D could serve as one possible agent in the development of immunomodulatory combination therapies for T1D.
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Affiliation(s)
- Gerlies Treiber
- Division of Endocrinology and Metabolism, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
| | - Barbara Prietl
- Division of Endocrinology and Metabolism, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
| | - Elke Fröhlich-Reiterer
- Department of General Paediatrics, Medical University Graz, Auenbruggerplatz 34, 8036 Graz, Austria.
| | - Evelyne Lechner
- Division of Endocrinology and Metabolism, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
| | - Anja Ribitsch
- Division of Endocrinology and Metabolism, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
| | - Maria Fritsch
- Department of Paediatrics, Medical University Vienna, Währinger Gürtel 18-20, 1090 Wien, Austria.
| | - Birgit Rami-Merhar
- Department of Paediatrics, Medical University Vienna, Währinger Gürtel 18-20, 1090 Wien, Austria.
| | - Claudia Steigleder-Schweiger
- Department of Paediatrics, Paracelsus Medical University Salzburg, Müllner Hauptstraße 48, 5020 Salzburg, Austria.
| | - Winfried Graninger
- Division of Rheumatology and Immunology, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
| | - Martin Borkenstein
- Department of General Paediatrics, Medical University Graz, Auenbruggerplatz 34, 8036 Graz, Austria.
| | - Thomas R Pieber
- Division of Endocrinology and Metabolism, Medical University Graz, Auenbruggerplatz 15, 8036 Graz, Austria.
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15
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Segovia-Gamboa N, Rodríguez-Arellano ME, Rangel-Cruz R, Sánchez-Díaz M, Ramírez-Reyes JC, Faradji R, González-Domínguez É, Sánchez-Torres C. Tolerogenic dendritic cells induce antigen-specific hyporesponsiveness in insulin- and glutamic acid decarboxylase 65-autoreactive T lymphocytes from type 1 diabetic patients. Clin Immunol 2014; 154:72-83. [PMID: 24993292 DOI: 10.1016/j.clim.2014.06.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 06/18/2014] [Accepted: 06/20/2014] [Indexed: 12/19/2022]
Abstract
Tolerogenic dendritic cells (tDC) constitute a promising therapy for autoimmune diseases, since they can anergize T lymphocytes recognizing self-antigens. Patients with type 1 diabetes mellitus (T1D) have autoreactive T cells against pancreatic islet antigens (insulin, glutamic acid decarboxylase 65 -GAD65-). We aimed to determine the ability of tDC derived from T1D patients to inactivate their insulin- and GAD65-reactive T cells. CD14+ monocytes and CD4+CD45RA- effector/memory lymphocytes were isolated from 25 patients. Monocyte-derived DC were generated in the absence (control, cDC) or presence of IL-10 and TGF-β1 (tDC), and loaded with insulin or GAD65. DC were cultured with T lymphocytes (primary culture), and cell proliferation and cytokine secretion were determined. These lymphocytes were rechallenged with insulin-, GAD65- or candidin-pulsed cDC (secondary culture) to assess whether tDC rendered T cells hyporesponsive to further stimulation. In the primary cultures, tDC induced significant lower lymphocyte proliferation and IL-2 and IFN-γ secretion than cDC; in contrast, tDC induced higher IL-10 production. Lymphocytes from 60% of patients proliferated specifically against insulin or GAD65 (group 1), whereas 40% did not (group 2). Most patients from group 1 had controlled glycemia. The secondary cultures showed tolerance induction to insulin or GAD65 in 14 and 10 patients, respectively. A high percentage of these patients (70-80%) belonged to group 1. Importantly, tDC induced antigen-specific T-cell hyporesponsiveness, since the responses against unrelated antigens were unaffected. These results suggest that tDC therapy against multiple antigens might be useful in a subset of T1D patients.
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Affiliation(s)
- Norma Segovia-Gamboa
- Department of Molecular Biomedicine, Centro de Investigación y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN). Av. I.P.N. 2508, C.P. 07360, Mexico City, Mexico
| | | | - Rafael Rangel-Cruz
- Department of Endocrinology, Hospital Regional "Lic. Adolfo López Mateos", ISSSTE, Av. Universidad 1321, Mexico City, Mexico
| | - Moisés Sánchez-Díaz
- Department of Pediatrics, Hospital Regional "Lic. Adolfo López Mateos", ISSSTE, Av. Universidad 1321, Mexico City, Mexico
| | - Julio César Ramírez-Reyes
- Department of Pediatrics, Hospital Regional "Lic. Adolfo López Mateos", ISSSTE, Av. Universidad 1321, Mexico City, Mexico
| | - Raquel Faradji
- Medicina Interna, Asociación Médica, Centro Médico ABC, Sur 136 #116, Mexico City, Mexico
| | - Érika González-Domínguez
- Department of Molecular Biomedicine, Centro de Investigación y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN). Av. I.P.N. 2508, C.P. 07360, Mexico City, Mexico
| | - Carmen Sánchez-Torres
- Department of Molecular Biomedicine, Centro de Investigación y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN). Av. I.P.N. 2508, C.P. 07360, Mexico City, Mexico.
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16
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Abstract
Type 1 diabetes mellitus (T1DM) is the result of autoimmune destruction of pancreatic β cells in genetically predisposed individuals with impaired immune regulation. The insufficiency in the modulation of immune attacks on the β cells might be partly due to genetic causes; indeed, several of the genetic variants that predispose individuals to T1DM have functional features of impaired immune regulation. Whilst defects in immune regulation in patients with T1DM have been identified, many patients seem to have immune regulatory capacities that are indistinguishable from those of healthy individuals. Insight into the regulation of islet autoimmunity might enable us to restore immune imbalances with therapeutic interventions. In this Review, we discuss the current knowledge on immune regulation and dysfunction in humans that is the basis of tissue-specific immune regulation as an alternative to generalized immune suppression.
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Affiliation(s)
- Bart O Roep
- Leiden University Medical Center, Department of Immunohaematology & Blood Transfusion, P. O. Box 9600, NL-2300 RC Leiden, Netherlands
| | - Timothy I M Tree
- Department of Immunobiology, King's College London, School of Medicine, London SE1 9RT, UK
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17
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Low frequency of regulatory T cells in the peripheral blood of children with type 1 diabetes diagnosed under the age of five. Arch Immunol Ther Exp (Warsz) 2012; 60:307-13. [PMID: 22684085 DOI: 10.1007/s00005-012-0177-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 05/11/2012] [Indexed: 10/28/2022]
Abstract
The highest annual increase in the incidence of type 1 diabetes (T1D) in children under the age of 5 years and aggressive process of β-cell destruction in this age group indicate the need to assess the immune system. The aim of this study was to evaluate regulatory T cells (Tregs) frequency in the peripheral blood of children <5 years of age with newly diagnosed T1D in comparison with diabetic children diagnosed at a later age and healthy controls. 40 children with newly diagnosed T1D (20 children <5 years of age and 20 older patients) and 40 age-matched controls were included in this study. Flow cytometric analysis of Tregs was performed using the following markers: CD4, CD25, CD127, FoxP3, IL-10, and TGF-β. Apoptosis was measured using anti-active caspase 3 monoclonal antibody. Fasting C-peptide and HbA1c were monitored as well. We showed that T1D children <5 years had lower C-peptide concentration than diabetic children ≥5 years of age (0.32 vs. 0.80 ng/ml, respectively, p = 0.0005). There was lower frequency of CD4(+)CD25(high)CD127(low)FoxP3(+) Tregs in T1D children <5 years than ≥5 years of age (0.87 vs. 1.56 %, respectively, p = 0.017). Diabetic children <5 years had lower CD4(+)CD25(high)CD127(low)FoxP3(+), CD4(+)CD25(high)IL-10, and CD4(+)CD25(high)TGF-β Tregs compared to age-matched controls. There was no difference in Tregs apoptosis between the examined groups. This study highlights the distinctiveness of diabetes in children <5 years of age. Understanding the differences of immune system activity in the young diabetic children would open the way to identify children at risk for T1D and enables the use of novel forms of intervention.
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18
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Szypowska A, Stelmaszczyk-Emmel A, Demkow U, Luczynski W. Evaluation of T regulatory cell apoptosis in children with newly recognized type 1 diabetes mellitus. Eur J Med Res 2011; 15 Suppl 2:198-201. [PMID: 21147651 PMCID: PMC4360305 DOI: 10.1186/2047-783x-15-s2-198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Type 1 diabetes is a metabolic disease characterized by an autoimmune, T-cell dependent destruction of insulin producing pancreatic beta cells. T regulatory cells (Tregs) are critical regulators of immune tolerance. OBJECTIVE The aim of the study was to investigate CD4 +CD25 highFoxP3 cell apoptosis in the peripheral blood of children with newly diagnosed type 1 diabetes mellitus. METHODS 34 children (15 girls and 19 boys) with new onset of type 1 diabetes mellitus, of the mean age 6.9 ±5.2 (range 0.9-17.5 yr) and 18 healthy controls (8 girls, 10 boys) of the mean age 7.3 ±4.6 (1.9-17.5 yr) were included into the study. Flow cytometric analysis of Tregs was performed using the following markers: anti-CD4, anti-CD25 and transcription factor FoxP3. Apoptosis was measured using anti-active caspase-3 monoclonal antibody. The percentage of apoptotic cells was measured within CD4 +CD25 highFoxP3+ cells. RESULTS AND CONCLUSION There was no statistically significant difference in the percentage of apoptotic CD4 +CD25 highFoxP3 + cells between children with diabetes and healthy subjects; the median value 0 (range 0-26.8) vs. 0 (range 0-2.6), respectively (P = 0.302). Further, clinical studies on a larger cohort of diabetic children are needed to evaluate T regulatory cell apoptosis, especially for future immune-based therapy.
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19
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Kaminitz A, Askenasy EM, Yaniv I, Stein J, Askenasy N. Apoptosis of purified CD4+ T cell subsets is dominated by cytokine deprivation and absence of other cells in new onset diabetic NOD mice. PLoS One 2010; 5:e15684. [PMID: 21209873 PMCID: PMC3013115 DOI: 10.1371/journal.pone.0015684] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 11/22/2010] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Regulatory T cells (Treg) play a significant role in immune homeostasis and self-tolerance. Excessive sensitivity of isolated Treg to apoptosis has been demonstrated in NOD mice and humans suffering of type 1 diabetes, suggesting a possible role in the immune dysfunction that underlies autoimmune insulitis. In this study the sensitivity to apoptosis was measured in T cells from new onset diabetic NOD females, comparing purified subsets to mixed cultures. PRINCIPAL FINDINGS Apoptotic cells are short lived in vivo and death occurs primarily during isolation, manipulation and culture. Excessive susceptibility of CD25(+) T cells to spontaneous apoptosis is characteristic of isolated subsets, however disappears when death is measured in mixed splenocyte cultures. In variance, CD25(-) T cells display balanced sensitivity to apoptosis under both conditions. The isolation procedure removes soluble factors, IL-2 playing a significant role in sustaining Treg viability. In addition, pro- and anti-apoptotic signals are transduced by cell-to-cell interactions: CD3 and CD28 protect CD25(+) T cells from apoptosis, and in parallel sensitize naïve effector cells to apoptosis. Treg viability is modulated both by other T cells and other subsets within mixed splenocyte cultures. Variations in sensitivity to apoptosis are often hindered by fast proliferation of viable cells, therefore cycling rates are mandatory to adequate interpretation of cell death assays. CONCLUSIONS The sensitivity of purified Treg to apoptosis is dominated by cytokine deprivation and absence of cell-to-cell interactions, and deviate significantly from measurements in mixed populations. Balanced sensitivity of naïve/effector and regulatory T cells to apoptosis in NOD mice argues against the concept that differential susceptibility affects disease evolution and progression.
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Affiliation(s)
- Ayelet Kaminitz
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Enosh M. Askenasy
- Soroka Medical School, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Isaac Yaniv
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Department of Pediatric Hematology-Oncology, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Jerry Stein
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- Bone Marrow Transplant Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Nadir Askenasy
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
- * E-mail:
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20
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Glisic S, Ehlenbach S, Jailwala P, Waukau J, Jana S, Ghosh S. Inducible regulatory T cells (iTregs) from recent-onset type 1 diabetes subjects show increased in vitro suppression and higher ITCH levels compared with controls. Cell Tissue Res 2010; 339:585-95. [PMID: 20143240 DOI: 10.1007/s00441-009-0900-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 10/13/2009] [Indexed: 12/30/2022]
Abstract
CD4+CD25+(high) regulatory T cells (Tregs) play a pivotal role in the control of the immune response. A growing body of evidence suggests the reduced function of these cells in autoimmune diseases, including type 1 diabetes (T1D). Restoration of their function can potentially delay further disease development. In the present study, we have converted conventional effector T cells into induced Tregs (iTregs) in recent-onset (RO) T1D (n=9) and compared them with the same cells generated in controls (n=12) and in long-standing (LS) T1D subjects (n=9). The functional potential of in-vitro-generated Tregs was measured by using an in vitro proliferation assay. We noted that the suppressive potential of iTregs exceeded that of natural regulatory T cells (nTregs) only in the RO T1D subjects. We showed that iTregs from RO T1D subjects had increased expression of Foxp3, E3 ubiquitin ligase (ITCH) and TGF-beta-inducible early gene 1 (TIEG1) compared with control and LS T1D subjects. We also expanded natural, thymically derived Tregs (nTregs) and compared the functional ability of these cells between subject groups. Expanded cells from all three subject groups were suppressive. RO T1D subjects were the only group in which both iTregs and expanded Tregs were functional, suggesting that the inflammatory milieu impacts in vitro Treg generation. Future longitudinal studies should delineate the actual contribution of the stage of disease to the quality of in-vitro-generated Tregs.
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Affiliation(s)
- Sanja Glisic
- Max McGee National Center for Juvenile Diabetes and Human Molecular Genetic Center, Department of Pediatrics, Medical College of Wisconsin, Children's Hospital of Wisconsin, Milwaukee, 53226, USA
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21
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Jana S, Jailwala P, Haribhai D, Waukau J, Glisic S, Grossman W, Mishra M, Wen R, Wang D, Williams CB, Ghosh S. The role of NF-kappaB and Smad3 in TGF-beta-mediated Foxp3 expression. Eur J Immunol 2009; 39:2571-83. [PMID: 19701891 DOI: 10.1002/eji.200939201] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The transcription factor Foxp3 is essential for the development of functional, natural Treg (nTreg), which plays a prominent role in self-tolerance. Suppressive Foxp3(+) Treg cells can be generated from naïve T cells ex vivo, following TCR and TGF-beta1 stimulations. However, the molecular contributions from the different arms of these pathways leading to Foxp3 expression are not fully understood. TGF-beta1-activated Smad3 plays a major role in the expression of Foxp3, since TGF-beta1-induced-Treg generation from Smad3(-/-) mice is markedly reduced and abolished by inactivating Smad2. In the TCR pathway, deletion of Bcl10, which activates NF-kappaB, markedly reduces both IL-2 and Foxp3 production. However, partial rescue of Foxp3 expression occurs on addition of exogenous IL-2. TGF-beta1 significantly attenuates NF-kappaB binding to the Foxp3 promoter, while inducing Foxp3 expression. Furthermore, deletion of p50, a NF-kappaB subunit, results in increased Foxp3 expression despite a decline in the IL-2 production. We posit several TCR-NF-kappaB pathways, some increasing (Bcl10-IL-2-Foxp3) while others decreasing (p50-Foxp3) Foxp3 expression, with the former predominating. A better understanding of Foxp3 regulation could be useful in dissecting the cause of Treg dysfunction in several autoimmune diseases and for generating more potent TGF-beta1-induced-Treg cells for therapeutic purposes.
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Affiliation(s)
- Srikanta Jana
- The Max McGee National Center for Juvenile Diabetes and Human Molecular Genetics Center, Medical College of Wisconsin and Children's Research Institute of Children's Hospital of Wisconsin, WI 53226, USA
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22
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Price CL, Knight SC. Methylglyoxal: possible link between hyperglycaemia and immune suppression? Trends Endocrinol Metab 2009; 20:312-7. [PMID: 19709901 DOI: 10.1016/j.tem.2009.03.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 03/31/2009] [Accepted: 03/31/2009] [Indexed: 11/25/2022]
Abstract
No matter the cause of diabetes, the result is always hyperglycaemia. This excess glucose metabolism drives several damage pathways and raises concentrations of the reactive dicarbonyl, methylglyoxal (MG). MG can modify the structure and function of target molecules by forming advanced glycation end-products (AGEs) that act through their receptor (RAGE) to perpetuate vascular and neuronal injury responsible for long-term complications of diabetes. Diabetes patients also suffer lower resistance to many common infections, although the cause(s) for this lower resistance remains elusive. Here, we review recent evidence concerning immune suppression in diabetes and discuss the effects of MG on components of the immune system. We suggest that MG could be a missing link between hyperglycaemia and immune suppression in diabetes.
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Affiliation(s)
- Claire L Price
- Antigen Presentation Research Group, Imperial College London Faculty of Medicine, Level 7W, NWLH campus, Watford Road, Harrow, Middlesex, HA1 3UJ, UK
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23
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Jailwala P, Waukau J, Glisic S, Jana S, Ehlenbach S, Hessner M, Alemzadeh R, Matsuyama S, Laud P, Wang X, Ghosh S. Apoptosis of CD4+ CD25(high) T cells in type 1 diabetes may be partially mediated by IL-2 deprivation. PLoS One 2009; 4:e6527. [PMID: 19654878 PMCID: PMC2716541 DOI: 10.1371/journal.pone.0006527] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Accepted: 07/02/2009] [Indexed: 01/26/2023] Open
Abstract
Background Type 1 diabetes (T1D) is a T-cell mediated autoimmune disease targeting the insulin-producing pancreatic β cells. Naturally occurring FOXP3+CD4+CD25high regulatory T cells (Tregs) play an important role in dominant tolerance, suppressing autoreactive CD4+ effector T cell activity. Previously, in both recent-onset T1D patients and β cell antibody-positive at-risk individuals, we observed increased apoptosis and decreased function of polyclonal Tregs in the periphery. Our objective here was to elucidate the genes and signaling pathways triggering apoptosis in Tregs from T1D subjects. Principal Findings Gene expression profiles of unstimulated Tregs from recent-onset T1D (n = 12) and healthy control subjects (n = 15) were generated. Statistical analysis was performed using a Bayesian approach that is highly efficient in determining differentially expressed genes with low number of replicate samples in each of the two phenotypic groups. Microarray analysis showed that several cytokine/chemokine receptor genes, HLA genes, GIMAP family genes and cell adhesion genes were downregulated in Tregs from T1D subjects, relative to control subjects. Several downstream target genes of the AKT and p53 pathways were also upregulated in T1D subjects, relative to controls. Further, expression signatures and increased apoptosis in Tregs from T1D subjects partially mirrored the response of healthy Tregs under conditions of IL-2 deprivation. CD4+ effector T-cells from T1D subjects showed a marked reduction in IL-2 secretion. This could indicate that prior to and during the onset of disease, Tregs in T1D may be caught up in a relatively deficient cytokine milieu. Conclusions In summary, expression signatures in Tregs from T1D subjects reflect a cellular response that leads to increased sensitivity to apoptosis, partially due to cytokine deprivation. Further characterization of these signaling cascades should enable the detection of genes that can be targeted for restoring Treg function in subjects predisposed to T1D.
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Affiliation(s)
- Parthav Jailwala
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Jill Waukau
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Sanja Glisic
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Srikanta Jana
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Sarah Ehlenbach
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Martin Hessner
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Ramin Alemzadeh
- Children's Hospital of Wisconsin Diabetes Center, Pediatric Endocrinology and Metabolism, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Shigemi Matsuyama
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Purushottam Laud
- Division of Biostatistics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Xujing Wang
- Department of Physics & the Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Soumitra Ghosh
- The Max McGee National Research Center for Juvenile Diabetes and The Human and Molecular Genetics Center, Department of Pediatrics at the Medical College of Wisconsin and the Children's Research Institute of the Children's Hospital of Wisconsin, Milwaukee, Wisconsin, United States of America
- * E-mail:
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Lawson JM, Tremble J, Dayan C, Beyan H, Leslie RDG, Peakman M, Tree TIM. Increased resistance to CD4+CD25hi regulatory T cell-mediated suppression in patients with type 1 diabetes. Clin Exp Immunol 2009; 154:353-9. [PMID: 19037920 DOI: 10.1111/j.1365-2249.2008.03810.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Type I diabetes (T1D) is a T cell-mediated autoimmune disease characterized by loss of tolerance to islet autoantigens, leading to the destruction of insulin-producing beta cells. Peripheral tolerance to self is maintained in health through several regulatory mechanisms, including a population of CD4+CD25hi naturally occurring regulatory T cells (T(regs)), defects in which could contribute to loss of self-tolerance in patients with T1D. We have reported previously that near to T1D onset, patients demonstrate a reduced level of suppression by CD4+CD25hi T(regs) of autologous CD4+CD25- responder cells. Here we demonstrate that this defective regulation is also present in subjects with long-standing T1D (> 3 years duration; P = 0.009). No difference was observed in forkhead box P3 or CD127 expression on CD4+CD25hi T cells in patients with T1D that could account for this loss of suppression. Cross-over co-culture assays demonstrate a relative resistance to CD4+CD25hi T(reg)-mediated suppression within the CD4+CD25- T cells in all patients tested (P = 0.002), while there appears to be heterogeneity in the functional ability of CD4+CD25hi T(regs) from patients. In conclusion, this work demonstrates that defective regulation is a feature of T1D regardless of disease duration and that an impaired ability of responder T cells to be suppressed contributes to this defect.
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Affiliation(s)
- J M Lawson
- King's College London, Department of Immunobiology, King's College London, London, UK
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25
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Genetic association of HLA DQB1 with CD4+CD25+(high) T-cell apoptosis in type 1 diabetes. Genes Immun 2009; 10:334-40. [PMID: 19295543 DOI: 10.1038/gene.2009.14] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Type 1 diabetes (T1D) has a strong genetic component and the major locus lies in the HLA DQB1 region. We found earlier an increased apoptosis with decreased viability and function of the CD4+CD25+(high) T-cell subset (Treg) in human subjects with recent-onset T1D and in multiple autoantibody-positive, high at-risk individuals. Tregs normally inhibit or delay onset of T1D in animal models and increased Treg apoptosis could bring on or accelerate disease from effector T-cell-mediated destruction of insulin-producing beta cells. In this study, we test the hypothesis that HLA DQB1 genotypes are associated with increased CD4+CD25+(high) T-cell apoptosis. HLA DQ-based genetic risk status was significantly associated with CD4+CD25+(high) T-cell apoptosis, after adjustment for age, gender and phenotypic status (n=83, F=4.04 (d.f.=3), P=0.01). Unaffected, autoantibody-negative high risk HLA DQB1 control subjects showed increased CD4+CD25+(high) apoptosis levels compared with low risk HLA DQB1 control subjects (n=26, P=0.002), confirming that the association precedes disease. The association of specific HLA DQB1 genotypes with Treg apoptosis was also tested, showing significance for HLA DQB1*0302, DQB1*0201 and HLA DQB1*0602 alleles. Our study shows an association of HLA DQB1 genotypes with CD4+CD25+(high) T-cell apoptosis, which implicates CD4+CD25+(high) T-cell apoptosis as a new intermediate trait for T1D.
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Strauss L, Bergmann C, Whiteside TL. Human circulating CD4+CD25highFoxp3+ regulatory T cells kill autologous CD8+ but not CD4+ responder cells by Fas-mediated apoptosis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2009; 182:1469-80. [PMID: 19155494 PMCID: PMC3721355 DOI: 10.4049/jimmunol.182.3.1469] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Mechanisms utilized by human regulatory T cells (Treg) for elimination of effector cells may vary. We investigated the possibility that the mechanism of Treg suppression depends on Fas/FasL-mediated apoptosis of responder cells (RC). CD4(+)CD25(high)Foxp3(+) Treg and autologous CD4(+)CD25(-) and CD8(+)CD25(-) subsets of RC were isolated from blood of 25 cancer patients and 15 normal controls and cocultured in the presence of OKT3 and IL-2 (150 or 1000 IU/ml). Suppression of RC proliferation was measured in CFSE assays. RC and Treg apoptosis was monitored by 7-aminoactinomycin D staining in flow-based cytotoxicity assays. Treg from all subjects expressed CD95(+), but only Treg from cancer patients expressed CD95L. These Treg, when activated via TCR plus IL-2, up-regulated CD95 and CD95L expression (p < 0.001) and suppressed CD8(+) RC proliferation (p < 0.001) by inducing Fas-mediated apoptosis. However, Treg cocultured with CD4(+) RC suppressed proliferation independently of Fas/FasL. In cocultures, Treg were found to be resistant to apoptosis in the presence of 1000 IU/ml IL-2, but at lower IL-2 concentrations (150 IU/ml) they became susceptible to RC-induced death. Thus, Treg and RC can reciprocally regulate Treg survival, depending on IL-2 concentrations present in cocultures. This divergent IL-2-dependent resistance or sensitivity of Treg and RC to apoptosis is amplified in patients with cancer.
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Affiliation(s)
- Laura Strauss
- University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213
| | - Christoph Bergmann
- University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213
- Department of Otorhinolarnygology, University of Duisburg-Essen, Essen, Germany
| | - Theresa L. Whiteside
- University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213
- Departments of Pathology, Immunology and Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15232
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Secor ER, Singh A, Guernsey LA, McNamara JT, Zhan L, Maulik N, Thrall RS. Bromelain treatment reduces CD25 expression on activated CD4+ T cells in vitro. Int Immunopharmacol 2009; 9:340-6. [PMID: 19162239 DOI: 10.1016/j.intimp.2008.12.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Revised: 11/18/2008] [Accepted: 12/17/2008] [Indexed: 12/14/2022]
Abstract
Bromelain (Br), an extract from pineapple stem with cysteine protease activity, exerts anti-inflammatory effects in a number of inflammatory models. We have previously shown that Br treatment decreased activated CD4(+) T cells and has a therapeutic role in an ovalbumin-induced murine model of allergic airway disease. The current study was designed to determine the effect of Br on CD4(+) T cell activation, specifically the expression of CD25 in vitro. CD25 is up regulated upon T cell activation, found as a soluble fraction (sCD25) and is a therapeutic target in inflammation, autoimmunity and allergy. Br treatment of anti-CD3 stimulated CD4(+) T cells reduced CD25 expression in a dose and time dependent manner. This reduction of CD25 was dependent on the proteolytic action of Br as the addition of E64 (a cysteine protease inhibitor) abrogated this response. The concentration of sCD25 was increased in supernatants of Br treated activated CD4(+) T cells as compared to control cells, suggesting that Br proteolytically cleaved cell-surface CD25. This novel mechanism of action identifies how Br may exert its therapeutic benefits in inflammatory conditions.
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Affiliation(s)
- Eric R Secor
- Department of Immunology, University of Connecticut Health Center 263 Farmington Ave, MC1319Farmington, CT 06030, USA.
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Bibliography. Current world literature. Diabetes and the endocrine pancreas II. Curr Opin Endocrinol Diabetes Obes 2008; 15:383-93. [PMID: 18594281 DOI: 10.1097/med.0b013e32830c6b8e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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