scholarly journals MBD2 acts as a repressor to maintain the homeostasis of the Th1 program in type 1 diabetes by regulating the STAT1-IFN-γ axis

Author(s):  
Tiantian Yue ◽  
Fei Sun ◽  
Faxi Wang ◽  
Chunliang Yang ◽  
Jiahui Luo ◽  
...  

AbstractThe methyl-CpG-binding domain 2 (MBD2) interprets DNA methylome-encoded information through binding to the methylated CpG DNA, by which it regulates target gene expression at the transcriptional level. Although derailed DNA methylation has long been recognized to trigger or promote autoimmune responses in type 1 diabetes (T1D), the exact role of MBD2 in T1D pathogenesis, however, remains poorly defined. Herein, we generated an Mbd2 knockout model in the NOD background and found that Mbd2 deficiency exacerbated the development of spontaneous T1D in NOD mice. Adoptive transfer of Mbd2−/− CD4 T cells into NOD.scid mice further confirmed the observation. Mechanistically, Th1 stimulation rendered the Stat1 promoter to undergo a DNA methylation turnover featured by the changes of DNA methylation levels or patterns along with the induction of MBD2 expression, which then bound to the methylated CpG DNA within the Stat1 promoter, by which MBD2 maintains the homeostasis of Th1 program to prevent autoimmunity. As a result, ectopic MBD2 expression alleviated CD4 T cell diabetogenicity following their adoptive transfer into NOD.scid mice. Collectively, our data suggest that MBD2 could be a viable target to develop epigenetic-based therapeutics against T1D in clinical settings.

2021 ◽  
Vol 12 ◽  
Author(s):  
Mei-Ling Yang ◽  
Fernanda M. C. Sodré ◽  
Mark J. Mamula ◽  
Lut Overbergh

The generation of post-translational modifications (PTMs) in human proteins is a physiological process leading to structural and immunologic variety in proteins, with potentially altered biological functions. PTMs often arise through normal responses to cellular stress, including general oxidative changes in the tissue microenvironment and intracellular stress to the endoplasmic reticulum or immune-mediated inflammatory stresses. Many studies have now illustrated the presence of ‘neoepitopes’ consisting of PTM self-proteins that induce robust autoimmune responses. These pathways of inflammatory neoepitope generation are commonly observed in many autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, and type 1 diabetes (T1D), among others. This review will focus on one specific PTM to self-proteins known as citrullination. Citrullination is mediated by calcium-dependent peptidylarginine deiminase (PAD) enzymes, which catalyze deimination, the conversion of arginine into the non-classical amino acid citrulline. PADs and citrullinated peptides have been associated with different autoimmune diseases, notably with a prominent role in the diagnosis and pathology of rheumatoid arthritis. More recently, an important role for PADs and citrullinated self-proteins has emerged in T1D. In this review we will provide a comprehensive overview on the pathogenic role for PADs and citrullination in inflammation and autoimmunity, with specific focus on evidence for their role in T1D. The general role of PADs in epigenetic and transcriptional processes, as well as their crucial role in histone citrullination, neutrophil biology and neutrophil extracellular trap (NET) formation will be discussed. The latter is important in view of increasing evidence for a role of neutrophils and NETosis in the pathogenesis of T1D. Further, we will discuss the underlying processes leading to citrullination, the genetic susceptibility factors for increased recognition of citrullinated epitopes by T1D HLA-susceptibility types and provide an overview of reported autoreactive responses against citrullinated epitopes, both of T cells and autoantibodies in T1D patients. Finally, we will discuss recent observations obtained in NOD mice, pointing to prevention of diabetes development through PAD inhibition, and the potential role of PAD inhibitors as novel therapeutic strategy in autoimmunity and in T1D in particular.


2011 ◽  
Vol 140 (5) ◽  
pp. S-369
Author(s):  
Luigi Notari ◽  
Shu Yan ◽  
Rex Sun ◽  
Viktoriya Grinchuk ◽  
Jennifer A. Stiltz ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Juan Huang ◽  
Qiyuan Tan ◽  
Ningwen Tai ◽  
James Alexander Pearson ◽  
Yangyang Li ◽  
...  

Type 1 diabetes is an autoimmune disease caused by T cell-mediated destruction of insulin-producing β cells. BDC2.5 T cells in BDC2.5 CD4+ T cell receptor transgenic Non-Obese Diabetic (NOD) mice (BDC2.5+ NOD mice) can abruptly invade the pancreatic islets resulting in severe insulitis that progresses rapidly but rarely leads to spontaneous diabetes. This prevention of diabetes is mediated by T regulatory (Treg) cells in these mice. In this study, we investigated the role of interleukin 10 (IL-10) in the inhibition of diabetes in BDC2.5+ NOD mice by generating Il-10-deficient BDC2.5+ NOD mice (BDC2.5+Il-10-/- NOD mice). Our results showed that BDC2.5+Il-10-/- NOD mice displayed robust and accelerated diabetes development. Il-10 deficiency in BDC2.5+ NOD mice promoted the generation of neutrophils in the bone marrow and increased the proportions of neutrophils in the periphery (blood, spleen, and islets), accompanied by altered intestinal immunity and gut microbiota composition. In vitro studies showed that the gut microbiota from BDC2.5+Il-10-/- NOD mice can expand neutrophil populations. Moreover, in vivo studies demonstrated that the depletion of endogenous gut microbiota by antibiotic treatment decreased the proportion of neutrophils. Although Il-10 deficiency in BDC2.5+ NOD mice had no obvious effects on the proportion and function of Treg cells, it affected the immune response and activation of CD4+ T cells. Moreover, the pathogenicity of CD4+ T cells was much increased, and this significantly accelerated the development of diabetes when these CD4+ T cells were transferred into immune-deficient NOD mice. Our study provides novel insights into the role of IL-10 in the modulation of neutrophils and CD4+ T cells in BDC2.5+ NOD mice, and suggests important crosstalk between gut microbiota and neutrophils in type 1 diabetes development.


2021 ◽  
Author(s):  
Farooq Syed ◽  
Divya Singhal ◽  
Koen Raedschelders ◽  
Preethi Krishnan ◽  
Robert N. Bone ◽  
...  

Background: Activation of stress pathways intrinsic to the β cell are thought to both accelerate β cell death and increase β cell immunogenicity in type 1 diabetes (T1D). However, information on the timing and scope of these responses is lacking. Methods: To identify temporal and disease-related changes in islet β cell protein expression, data independent acquisition-mass spectrometry was performed on islets collected longitudinally from NOD mice and NOD-SCID mice rendered diabetic through T cell adoptive transfer. Findings: In islets collected from female NOD mice at 10, 12, and 14 weeks of age, we found a time-restricted upregulation of proteins involved in the maintenance of β cell function and stress mitigation, followed by loss of expression of protective proteins that heralded diabetes onset. Pathway analysis identified EIF2 signaling and the unfolded protein response, mTOR signaling, mitochondrial function, and oxidative phosphorylation as commonly modulated pathways in both diabetic NOD mice and NOD-SCID mice rendered acutely diabetic by adoptive transfer, highlighting this core set of pathways in T1D pathogenesis. In immunofluorescence validation studies, β cell expression of protein disulfide isomerase A1 (PDIA1) and 14-3-3b were found to be increased during disease progression in NOD islets, while PDIA1 plasma levels were increased in pre-diabetic NOD mice and in the serum of children with recent-onset T1D compared to age and sex-matched non-diabetic controls. Interpretation: We identified a common and core set of modulated pathways across distinct mouse models of T1D and identified PDIA1 as a potential human biomarker of β cell stress in T1D.


2016 ◽  
Vol 18 (3) ◽  
pp. 178-187 ◽  
Author(s):  
Marie-Pierre Belot ◽  
Kambiz Nadéri ◽  
Clémence Mille ◽  
Pierre-Yves Boëlle ◽  
Alexandra Benachi ◽  
...  

2019 ◽  
Vol 240 (3) ◽  
pp. 403-416 ◽  
Author(s):  
Yoko Yagishita ◽  
Akira Uruno ◽  
Dionysios V Chartoumpekis ◽  
Thomas W Kensler ◽  
Masayuki Yamamoto

The transcription factor Nrf2 (NF-E2-related factor 2) plays a critical role in oxidative stress responses. Although activation of Nrf2 signaling is known to exert anti-inflammatory effects, the function of Nrf2 in inflammation-mediated autoimmune disorders, such as type 1 diabetes, is not well established. To address the roles of Nrf2 in protection against autoreactive T-cell-induced type 1 diabetes, we used non-obese diabetic (NOD) mice, which are a polygenic model of human type 1 diabetes, to generate a genetic model for assessment of the contribution of Nrf2 activation to prevention and/or treatment of type 1 diabetes. Because Keap1 (Kelch-like ECH-associated protein 1) negatively regulates Nrf2, we used Keap1 gene knockdown driven by either hypomorphic or knockout Keap1 alleles, which enhanced Nrf2 signaling to moderate or excess levels, respectively. Nrf2 activation in the NOD::Keap1 FA/– mice inhibited T-cell infiltration within or near the islets, ameliorated impairment of insulin secretion and prevented the development of diabetes mellitus. Notably, Nrf2 activation decreased both the plasma interferon-γ (IFN-γ) levels and the IFN-γ-positive cell numbers in the pancreatic islets. The amelioration of diabetes was also observed in the NOD mice with two hypomorphic Keap1 alleles (Keap1FA/FA) by intermediate activation of Nrf2. Both NOD::Keap1FA/– and NOD::Keap1FA/FA mice had a decreased incidence of diabetes mellitus, demonstrating that activation of Nrf2 signaling prevented the onset of type 1 diabetes mellitus in NOD mice. Thus, Nrf2 appears to be a potential target for the prevention and treatment of type 1 diabetes.


2018 ◽  
Author(s):  
◽  
Tobechukwu Kenneth Ukah

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Type 1 diabetes (T1D) is a chronic disease condition characterized by destruction of the insulin-producing [beta]-cells by self-reactive lymphocytes of the immune system. While some immunotherapeutic approaches against T1D directly target and modulate diabetogenic specific T cells or the entire T cell repertoire, other efforts utilize antigen presenting cells or T cell-regulating molecules to control the T cells. In chapter II, we set out to determine the role of regulatory cytokines, IL-4 and IL-13 in T1D progression. IL-4 and IL-13 are widely reported as anti-inflammatory cytokines, and both can signal via the IL-4R[alpha]/IL-13R[alpha]1 heteroreceptor (HR). To determine the role of these cytokines in T1D development, we generated NOD mice in which the IL-13R[alpha]1 arm of the HR is deleted, thereby rendering the HR nonfunctional. Surprisingly, the findings indicate that NOD mice lacking the HR (13R-/-) display resistance to T1D as the rise in blood glucose level (BGL) and islet inflammation were significantly delayed in these HR-deficient relative to HR-sufficient (13R+/+) mice. In fact, the frequency and spleen-to-pancreas dynamics of both Th1 and Th17 cells were affected in 13R-/- mice. This outcome is likely due to an increase in the frequency of mTGF[beta][subscript +]Foxp3[subscript int] regulatory T cells and persistence of CD206[subscript +] macrophage in the pancreas as both types of cells confer resistance to T1D upon transfer to 13R+/+ mice. These findings reveal new insights as to the role environmental IL-4/IL-13 and the HR play in peripheral tolerance and the development of T1D. In chapter III, we investigate the source of newly formed β-cells during recovery from overt T1D under a combination therapy that involves an immunoglobulin chimera, Ig-GAD2 and bone marrow cells transfer. This combination therapy proved effective in driving immune modulation of diabetogenic-specific T cells and repair of the islet vasculature leading to the formation of new endogenous [beta]-cells that were able to thrive and restore long-lasting normoglycemia. Our new findings reveal and suggest that the combination therapy leads to the formation of healthy islets by inducing division of residual β-cells and differentiation of precursor cells. Furthermore, while the pancreas is cleared of immune infiltration during recovery from disease, both the lymph nodes and spleen displayed a significant reduction in Th17 cells, and the disease did not rebound. These circumstances are relevant to humans as intervention could be made at early as well as late stages after diagnosis. Overall, these results provide insights on future immunotherapeutic measures of T1D using regulatory cytokines or intervention with an antigen-specific therapy.


2019 ◽  
Vol 104 (9) ◽  
pp. 4199-4213 ◽  
Author(s):  
Xinyu Xu ◽  
Min Shen ◽  
Ruiling Zhao ◽  
Yun Cai ◽  
Hemin Jiang ◽  
...  

Abstract Objective Impaired follicular regulatory T (Tfr) cells enhance T follicular helper cells activity, resulting in the expansion of autoreactive B cells and autoantibody production. However, the role of Tfr cells in the pathogenesis of type 1 diabetes (T1D) is unclear. Design We evaluated the expression and changes in function of circulating Tfr cells by studying patients with T1D alongside those with type 2 diabetes (T2D), first-degree relatives of T1D patients, and healthy controls. We also investigated the effects of Tfr cells on disease development in nonobese diabetic (NOD) mice and in an adoptive transfer model. Results Tfr cells were significantly decreased in both patient groups. However, they showed different correlations with fasting C-peptide (C-P) and the area under the curve of blood C-P in patients with T1D and T2D. The frequency of Tfr cells was associated with the number of positive autoantibodies and the titer of glutamic acid decarboxylase autoantibody in T1D patients. Furthermore, Tfr cells decreased significantly after 1 year of follow-up. We also observed Tfr cells in four T1D patients treated with rituximab. After rituximab therapy, the frequency of C-X-C motif chemokine receptor 5 (CXCR5)+ programmed death 1+ Tfr cells was decreased and of CXCR5+ inducible costimulator+ Tfr cells was increased in three patients. We also found that Tfr cells were associated with the development of diabetes in NOD mice and an adoptive transfer model. Conclusions Tfr cell deficiency could be involved in the pathogenesis of T1D. Therapy with Tfr cells has potential value for T1D. Modulation of these cells may enhance protective immunity to inhibit autoimmune diabetes.


Diabetes ◽  
2012 ◽  
Vol 61 (11) ◽  
pp. 2881-2892 ◽  
Author(s):  
R. Parsa ◽  
P. Andresen ◽  
A. Gillett ◽  
S. Mia ◽  
X.-M. Zhang ◽  
...  

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