scholarly journals Minimal Impact of a De Novo-Expressed  -Cell Autoantigen on Spontaneous Diabetes Development in NOD Mice

Diabetes ◽  
2007 ◽  
Vol 56 (4) ◽  
pp. 1059-1068 ◽  
Author(s):  
M. M. Martinic ◽  
A. E. Juedes ◽  
D. Bresson ◽  
D. Homann ◽  
K. Skak ◽  
...  
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.


Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 288-OR
Author(s):  
ANNIE PINEROS ◽  
ABHISHEK KULKARNI ◽  
KARA ORR ◽  
LINDSEY GLENN ◽  
CHRISTOPHER A. REISSAUS ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Gaurang Jhala ◽  
Claudia Selck ◽  
Jonathan Chee ◽  
Chun-Ting J. Kwong ◽  
Evan G. Pappas ◽  
...  

T-cell responses to insulin and its precursor proinsulin are central to islet autoimmunity in humans and non-obese diabetic (NOD) mice that spontaneously develop autoimmune diabetes. Mice have two proinsulin genes proinsulin -1 and 2 that are differentially expressed, with predominant proinsulin-2 expression in the thymus and proinsulin-1 in islet beta-cells. In contrast to proinsulin-2, proinsulin-1 knockout NOD mice are protected from autoimmune diabetes. This indicates that proinsulin-1 epitopes in beta-cells maybe preferentially targeted by autoreactive T cells. To study the contribution of proinsulin-1 reactive T cells in autoimmune diabetes, we generated transgenic NOD mice with tetracycline-regulated expression of proinsulin-1 in antigen presenting cells (TIP-1 mice) with an aim to induce immune tolerance. TIP-1 mice displayed a significantly reduced incidence of spontaneous diabetes, which was associated with reduced severity of insulitis and insulin autoantibody development. Antigen experienced proinsulin specific T cells were significantly reduced in in TIP-1 mice indicating immune tolerance. Moreover, T cells from TIP-1 mice expressing proinsulin-1 transferred diabetes at a significantly reduced frequency. However, proinsulin-1 expression in APCs had minimal impact on the immune responses to the downstream antigen islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP) and did not prevent diabetes in NOD 8.3 mice with a pre-existing repertoire of IGRP reactive T cells. Thus, boosting immune tolerance to proinsulin-1 partially prevents islet-autoimmunity. This study further extends the previously established role of proinsulin-1 epitopes in autoimmune diabetes in NOD mice.


2021 ◽  
Vol 12 ◽  
Author(s):  
Deepika Watts ◽  
Marthe Janßen ◽  
Mangesh Jaykar ◽  
Francesco Palmucci ◽  
Marc Weigelt ◽  
...  

Type 1 diabetes (T1D) represents a hallmark of the fatal multiorgan autoimmune syndrome affecting humans with abrogated Foxp3+ regulatory T (Treg) cell function due to Foxp3 gene mutations, but whether the loss of Foxp3+ Treg cell activity is indeed sufficient to promote β cell autoimmunity requires further scrutiny. As opposed to human Treg cell deficiency, β cell autoimmunity has not been observed in non-autoimmune-prone mice with constitutive Foxp3 deficiency or after diphtheria toxin receptor (DTR)-mediated ablation of Foxp3+ Treg cells. In the spontaneous nonobese diabetic (NOD) mouse model of T1D, constitutive Foxp3 deficiency did not result in invasive insulitis and hyperglycemia, and previous studies on Foxp3+ Treg cell ablation focused on Foxp3DTR NOD mice, in which expression of a transgenic BDC2.5 T cell receptor (TCR) restricted the CD4+ TCR repertoire to a single diabetogenic specificity. Here we revisited the effect of acute Foxp3+ Treg cell ablation on β cell autoimmunity in NOD mice in the context of a polyclonal TCR repertoire. For this, we took advantage of the well-established DTR/GFP transgene of DEREG mice, which allows for specific ablation of Foxp3+ Treg cells without promoting catastrophic autoimmune diseases. We show that the transient loss of Foxp3+ Treg cells in prediabetic NOD.DEREG mice is sufficient to precipitate severe insulitis and persistent hyperglycemia within 5 days after DT administration. Importantly, DT-treated NOD.DEREG mice preserved many clinical features of spontaneous diabetes progression in the NOD model, including a prominent role of diabetogenic CD8+ T cells in terminal β cell destruction. Despite the severity of destructive β cell autoimmunity, anti-CD3 mAb therapy of DT-treated mice interfered with the progression to overt diabetes, indicating that the novel NOD.DEREG model can be exploited for preclinical studies on T1D under experimental conditions of synchronized, advanced β cell autoimmunity. Overall, our studies highlight the continuous requirement of Foxp3+ Treg cell activity for the control of genetically pre-installed autoimmune diabetes.


Diabetes ◽  
2006 ◽  
Vol 55 (7) ◽  
pp. 2098-2105 ◽  
Author(s):  
P. Alard ◽  
J. N. Manirarora ◽  
S. A. Parnell ◽  
J. L. Hudkins ◽  
S. L. Clark ◽  
...  

2019 ◽  
Vol 7 (1) ◽  
pp. e000793
Author(s):  
William C Joesten ◽  
Audrey H Short ◽  
Michael A Kennedy

ObjectivesTo determine if spatial variations in gut permeability play a role in regulating type 1 diabetes (T1D) progression.Research design and methodsSpatially resolved duodenum, jejunum, ileum, and large intestine sections from end-stage T1D non-obese diabetic (NOD) mice were probed by immunohistochemistry to quantify zonulin levels as a measure of gut permeability in early-progressor and late-progressor NOD mice in comparison with non-progressor NOD mice and healthy NOR/LtJ control mice.ResultsZonulin levels were elevated in the small and large intestines in early-progressor and late-progressor NOD mice in comparison with non-progressor NOD mice and healthy NOR control mice. In early-onset mice, elevated zonulin levels were maximum in the duodenum and jejunum and decreased in the ileum and large intestine. In late-progressor mice, zonulin levels were elevated almost evenly along the small and large intestines. In non-progressor NOD mice, zonulin levels were comparable with NOR control levels in both the small and large intestines.ConclusionsElevated zonulin expression levels indicated that gut permeability was increased both in the small and large intestines in NOD mice that progressed to end-stage T1D in comparison with non-progressor NOD mice and healthy NOR control mice. Highest elevations in zonulin levels were observed in the duodenum and jejunum followed by the ileum and large intestines. Spatial variations in gut permeability appeared to play a role in regulating the rate and severity of T1D progression in NOD mice indicating that spatial variations in gut permeability should be investigated as a potentially important factor in human T1D progression.


1993 ◽  
Vol 178 (3) ◽  
pp. 793-803 ◽  
Author(s):  
P L Podolin ◽  
A Pressey ◽  
N H DeLarato ◽  
P A Fischer ◽  
L B Peterson ◽  
...  

The development of type I diabetes in the nonobese diabetic (NOD) mouse is under the control of multiple genes, one or more of which is linked to the major histocompatibility complex (MHC). The MHC class II region has been implicated in disease development, with expression of an I-E transgene in NOD mice shown to provide protection from insulitis and diabetes. To examine the effect of expressing an I-E+ or I-E- non-NOD MHC on the NOD background, three I-E+ and three I-E- NOD MHC congenic strains (NOD.H-2i5, NOD.H-2k, and NOD.H-2h2, and NOD.H-2h4, NOD.H-2i7, and NOD.H-2b, respectively) were developed. Of these strains, both I-E+ NOD.H-2h2 and I-E- NOD.H-2h4 mice developed insulitis, but not diabetes. The remaining four congenic strains were free of insulitis and diabetes. These results indicate that in the absence of the NOD MHC, diabetes fails to develop. Each NOD MHC congenic strain was crossed with the NOD strain to produce I-E+ and I-E- F1 mice; these mice thus expressed one dose of the NOD MHC and one dose of a non-NOD MHC on the NOD background. While a single dose of a non-NOD MHC provided a large degree of disease protection to all of the F1 strains, a proportion of I-E+ and I-E- F1 mice aged 5-12 mo developed insulitis and cyclophosphamide-induced diabetes. When I-E+ F1 mice were aged 9-17 mo, spontaneous diabetes developed as well. These data are the first to demonstrate that I-E+ NOD mice develop diabetes, indicating that expression of I-E in NOD mice is not in itself sufficient to prevent insulitis or diabetes. In fact, I-E- F1 strains were no more protected from diabetes than I-E+ F1 strains, suggesting that other non-NOD MHC-linked genes are important in protection from disease. Finally, transfer of NOD bone marrow into irradiated I-E+ F1 recipients resulted in high incidences of diabetes, indicating that expression of non-NOD MHC products in the thymus, in the absence of expression in bone marrow-derived cells, is not sufficient to provide protection from diabetes.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 848-848
Author(s):  
Allison Mayle ◽  
Grant Anthony Challen ◽  
Deqiang Sun ◽  
Mira Jeong ◽  
Min Luo ◽  
...  

Abstract Abstract 848 DNA methylation is an epigenetic modification in vertebrate genomes critical for regulation of gene expression. DNA methylation is catalyzed by a family of DNA methyltransferase enzymes, Dnmt1, Dnmt3a, and Dnmt3b. Dnmt1 is primarily a maintenance methyltransferase, targeting hemimethylated DNA to reestablish methylation marks after DNA replication. Dnmt3a and Dnmt3b are de novo methyltransferases that are essential for normal embryonic development. In humans, somatic mutations in DNTM3A have been identified in ∼20% of human acute myeloid leukemia (AML) and ∼10% of myelodysplastic syndrome (MDS) patients, but the mechanisms through which these mutations contribute to pathogenesis is not well understood. Congenital mutations in DNMT3B can cause ICF (immunodeficiency, centromeric instability, and facial anomalies) syndrome. These patients exhibit chromosomal instability due to heterochromatin decondensation and demethylation of satellite DNA. Our group has recently reported that Dnmt3a is essential for HSC differentiation (Challen Nature Genetics, 2011). Conditional knockout of Dnmt3a (Dnmt3a-KO) resulted in HSCs that could not sustain peripheral blood generation after serial transplantation, but phenotypically defined HSCs accumulated in the bone marrow. Dnmt3b is also highly expressed in HSCs, but its contribution to gene regulation in hematopoiesis is unclear. Here, we examine the role of Dnmt3b, alone and in combination with Dnmt3a KO, in the regulation of hematopoiesis. We performed conditional ablation of Dnmt3b, as well as Dnmt3a and Dnmt3b simultaneously using the Mx1-cre system. Unlike the Dnmt3a-KO HSCs, loss of Dnmt3b had a minimal impact on blood production. Even after several rounds of transplantation, 3b-KO HSCs performed similarly to WT controls. However, the Dnmt3ab-dKO (double knock-out) peripheral blood contribution was quickly and severely diminished, accompanied by a dramatic accumulation of Dnmt3ab-dKO HSCs in the bone marrow (Figure 1). The dKO phenotype paralleled that of the 3a-KO HSC, but was more extreme. To examine the impact of loss of Dnmt3a and -3b on DNA methylation in HSCs, we performed Whole Genome Bisulfite Sequencing (WGBS) on Dnmt3a-KO, Dnmt3ab- dKO and control HSCs. As we previously found with more limited DNA methylation analysis, loss of Dnmt3a led to both increases and decreases of DNA methylation at distinct genomic regions (Challen, Nature Genetics, 2011). However, loss of both Dnmt3a and -3b primarily resulted in loss of DNA methylation that was much more extensive than that seen in the 3a-KO. In addition, RNAseq of the mutant HSCs revealed increased expression of repetitive elements, inappropriate splicing, and truncation of 3ÕUTRs. To gain insight into the accumulation of Dnmt3ab-dKO HSCs in the bone marrow, we performed a time course analysis of the proliferation and apoptosis status of the HSCs. Every four weeks after transplantation of HSCs, we sacrificed a cohort of 3 control and 3 dKO mice, counted donor derived HSCs in the bone marrow, and analyzed their Ki67 and Annexin V expression. Up to 12 weeks post-transplant, no significant differences are seen in the expression of Ki67 or Annexin V. These data show that while Dnmt3b alone has minimal impact on DNA methylation in HSCs, Dnmt3a and -3b act synergistically to effect gene expression changes that permit HSC differentiation. In the absence of both of these de novo DNA methyltransferases, there is an immediate and extreme shift toward self-renewal of dKO HSCs. The Ki67 and Annexin V expression patterns suggest that a lack of de novo DNA methylation does not affect the proliferation or apoptosis of HSCs, but instead that the accumulation of HSCs and lack of peripheral blood contribution is primarily due to an imbalance between self-renewal and differentiation. By understanding the mechanisms through which Dnmt3a and -3b exert these effects, we should identify genes that are critical for normal hematopoietic differentiation. These genes may serve as targets for therapeutic intervention in malignancies caused by defective DNA methyltransferases. Figure 1: HSC composition of the bone marrow after secondary transplantation of control (left) and double Dnmt3a/3b KO (right) HSCs. After control HSC transplantation, HSCs comprise ∼0.01% of whole bone marrow. After transplantation of dKO HSCs, phenotypically-defined HSCs (KLS CD34–Flk2–) comprise ∼0.48% of bone marrow. Figure 1:. HSC composition of the bone marrow after secondary transplantation of control (left) and double Dnmt3a/3b KO (right) HSCs. After control HSC transplantation, HSCs comprise ∼0.01% of whole bone marrow. After transplantation of dKO HSCs, phenotypically-defined HSCs (KLS CD34–Flk2–) comprise ∼0.48% of bone marrow. Disclosures: No relevant conflicts of interest to declare.


2005 ◽  
Vol 175 (12) ◽  
pp. 8401-8408 ◽  
Author(s):  
Toshikatsu Shigihara ◽  
Akira Shimada ◽  
Yoichi Oikawa ◽  
Hiroyuki Yoneyama ◽  
Yasuhiko Kanazawa ◽  
...  

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