scholarly journals Oligofructose as an adjunct in treatment of diabetes in NOD mice

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Clement Chan ◽  
Colin M. Hyslop ◽  
Vipul Shrivastava ◽  
Andrea Ochoa ◽  
Raylene A. Reimer ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Insulin Sensitivity ◽  
Gut Microbiota ◽  
Beta Cell ◽  
Beta Cells ◽  
Adjunctive Therapy ◽  
Remission Rate ◽  
Beta Cell Proliferation ◽  
Autoimmune Attack

Abstract In type 1 diabetes, restoration of normoglycemia can be achieved if the autoimmune attack on beta cells ceases and insulin requirement is met by the residual beta cells. We hypothesize that an adjunctive therapy that reduces insulin demand by increasing insulin sensitivity will improve the efficacy of an immunotherapy in reversing diabetes. We tested the gut microbiota-modulating prebiotic, oligofructose (OFS), as the adjunctive therapy. We treated non-obese diabetic mice with an immunotherapy, monoclonal anti-CD3 antibody (aCD3), with or without concurrent dietary supplement of OFS. After 8 weeks of OFS supplement, the group that received both aCD3 and OFS (aCD3 + OFS) had a higher diabetes remission rate than the group that received aCD3 alone. The aCD3 + OFS group had higher insulin sensitivity accompanied by reduced lymphocytic infiltrate into the pancreatic islets, higher beta-cell proliferation rate, higher pancreatic insulin content, and secreted more insulin in response to glucose. The addition of OFS also caused a change in gut microbiota, with a higher level of Bifidobacterium and lower Clostridium leptum. Hence, our results suggest that OFS can potentially be an effective therapeutic adjunct in the treatment of type 1 diabetes by improving insulin sensitivity and beta-cell function, leading to improved glycemic control.

scholarly journals Similarities Between Bacterial GAD and Human GAD65: Implications in Gut Mediated Autoimmune Type 1 Diabetes

2021 ◽  
Author(s):  
Monica Westley ◽  
Tiffany Richardson ◽  
Suhana Bedi ◽  
Baofeng Jia ◽  
Fiona S.L. Brinkman ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cells ◽  
Gut Microbiome ◽  
Pancreatic Beta Cells ◽  
Acid Decarboxylase ◽  
Host Immune System ◽  
Gamma Aminobutyric Acid ◽  
Human Gut ◽  
Autoimmune Attack

Abstract    A variety of islet autoantibodies (AAbs) can predict and possibly dictate eventual type 1 diabetes (T1D) diagnosis. Upwards of 75% of those with T1D are positive for AAbs against glutamic acid decarboxylase (GAD65), a producer of gamma-aminobutyric acid (GABA) in human pancreatic beta cells. Interestingly, bacterial populations within the human gut also express GAD65 and produce GABA. Evidence suggests that dysbiosis of the microbiome may correlate with T1D pathogenesis and physiology. Therefore, autoimmune linkages between the gut microbiome and islets susceptible to autoimmune attack need to be further elucidated. Utilizing silico analyses, we show here that 25 GAD sequences from different human gut bacterial sources show sequence and motif similarities to human beta cell GAD65. Our motif analyses determined that a majority of gut GAD sequences contain the pyroxical dependent decarboxylase domain of human GAD65 which is important for its enzymatic activity. Additionally, we showed overlap with known human GAD65 T-cell receptor epitopes which may implicate the immune destruction of beta cells. Thus, we propose a physiological hypothesis in which changes in the gut microbiome in those with T1D result in a release of bacterial GAD, thus causing miseducation of the host immune system. Due to the notable similarities, we found between humans and bacterial GAD, these deputized immune cells may then go on to target human beta cells leading to the development of T1D.

scholarly journals On the dynamics of the human endocrine pancreas and potential consequences for the development of type 1 diabetes

2019 ◽  
Vol 57 (4) ◽  
pp. 503-511 ◽  
Author(s):  
Oskar Skog ◽  
Olle Korsgren
Keyword(s):  
Cell Proliferation ◽  
Type 1 Diabetes ◽  
Beta Cell ◽  
Endocrine Pancreas ◽  
Blood Perfusion ◽  
Beta Cell Proliferation ◽  
Vascular Events ◽  
Islet Neogenesis ◽  
Islet Mass

Abstract Little is known about the human islet life span, and beta-cell neogenesis is generally considered rare in adults. However, based on available data on beta-cell proliferation, calculations can be made suggesting that the dynamics of the endocrine pancreas is considerable even during adulthood, with islet neogenesis and a sustained increase in size of already formed islets. Islet-associated hemorrhages, frequently observed in most mammals including humans, could account for a considerable loss of islet parenchyma balancing the constant beta-cell proliferation. Notably, in subjects with type 1 diabetes, periductal accumulation of leukocytes and fibrosis is frequently observed, findings that are likely to negatively affect islet neogenesis from endocrine progenitor cells present in the periductal area. Impaired neogenesis would disrupt the balance, result in loss of islet mass, and eventually lead to beta-cell deficiency and compromised glucose metabolism, with increased islet workload and blood perfusion of remaining islets. These changes would impose initiation of a vicious circle further increasing the frequency of vascular events and hemorrhages within remaining islets until the patient eventually loses all beta-cells and becomes c-peptide negative.

scholarly journals Human gut microbiota transferred to germ-free NOD mice modulate the progression towards type 1 diabetes regardless of the pace of beta cell function loss in the donor

Diabetologia ◽  
2019 ◽  
Vol 62 (7) ◽  
pp. 1291-1296 ◽  
Author(s):  
Vit Neuman ◽  
Ondrej Cinek ◽  
David P. Funda ◽  
Tomas Hudcovic ◽  
Jaroslav Golias ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Gut Microbiota ◽  
Beta Cell ◽  
Beta Cell Function ◽  
Cell Function ◽  
Nod Mice ◽  
Human Gut ◽  
Germ Free ◽  
Function Loss

Beta-cell markers and autoantigen expression by a human insulinoma cell line: similarities to native beta cells

1996 ◽  
Vol 150 (1) ◽  
pp. 113-120 ◽  
Author(s):  
M G Cavallo ◽  
F Dotta ◽  
L Monetini ◽  
S Dionisi ◽  
M Previti ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Monoclonal Antibodies ◽  
Beta Cell ◽  
Cell Line ◽  
Beta Cells ◽  
Cell Markers ◽  
Insulinoma Cell ◽  
Insulinoma Cell Line ◽  
Human Insulinoma

Abstract In the present study we have evaluated the expression of different beta-cell markers, islet molecules and autoantigens relevant in diabetes autoimmunity by a human insulinoma cell line (CM) in order to define its similarities with native beta cells and to discover whether it could be considered as a model for studies on immunological aspects of Type 1 diabetes. First, the positivity of the CM cell line for known markers of neuroendocrine derivation was determined by means of immunocytochemical analysis using different anti-islet monoclonal antibodies including A2B5 and 3G5 reacting with islet gangliosides, and HISL19 binding to an islet glycoprotein. Secondly, the expression and characteristics of glutamic acid decarboxylase (GAD) and of GM2-1 ganglioside, both known to be islet autoantigens in diabetes autoimmunity and expressed by human native beta cells, were investigated in the CM cell line. The pattern of ganglioside expression in comparison to that of native beta cells was also evaluated. Thirdly, the binding of diabetic sera to CM cells reacting with islet cytoplasmic antigens (ICA) was studied by immunohistochemistry. The results of this study showed that beta cell markers identified by anti-islet monoclonal antibodies A2B5, 3G5 and HISL-19 are expressed by CM cells; similarly, islet molecules such as GAD and GM2-1 ganglioside are present and possess similar characteristics to those found in native beta cells; the pattern of expression of other gangliosides by CM cells is also identical to human pancreatic islets; beta cell autoantigen(s) reacting with antibodies present in islet cell antibodies (ICA) positive diabetic sera identified by ICA binding are also detectable in this insulinoma cell line. We conclude that CM cells show close similarities to native beta cells with respect to the expression of neuroendocrine markers, relevant beta cell autoantigens in Type 1 diabetes (GAD, GM2-1, ICA antigen), and other gangliosides. Therefore, this insulinoma cell line may be considered as an ideal model for studies aimed at investigating autoimmune phenomena occurring in Type 1 diabetes. Journal of Endocrinology (1996) 150, 113–120

scholarly journals Beta Cell Autophagy in the Pathogenesis of Type 1 Diabetes

2021 ◽  
Author(s):  
Charanya Muralidharan ◽  
Amelia K Linnemann
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Beta Cells ◽  
Pancreatic Beta Cells ◽  
Potential Role ◽  
Cell Dysfunction ◽  
Unconventional Secretion ◽  
Insulin Dependent

Type 1 diabetes is an insulin-dependent, autoimmune disease where the pancreatic beta cells are destroyed resulting in hyperglycemia. This multi-factorial disease involves multiple environmental and genetic factors, and has no clear etiology. Accumulating evidence suggests that early signaling defects within the beta cells may promote a change in the local immune mileu, contributing to autoimmunity. Therefore, many studies have been focused on intrinsic beta cell mechanisms that aid in restoration of cellular homeostasis under environmental conditions that cause dysfunction. One of these intrinsic mechanisms to promote homeostasis is autophagy, defects in which are clearly linked with beta cell dysfunction in the context of type 2 diabetes. Recent studies have now also pointed towards beta cell autophagy defects in the context of type 1 diabetes. In this perspectives review, we will discuss the evidence supporting a role for beta cell autophagy in the pathogenesis of type 1 diabetes, including a potential role for unconventional secretion of autophagosomes/lysosomes in the changing dialogue between the beta cell and immune cells.

scholarly journals Type 1 diabetes risk genes mediate pancreatic beta cell survival in response to proinflammatory cytokines

2021 ◽  
Author(s):  
Paola Benaglio ◽  
Han Zhu ◽  
Mei-Lin Okino ◽  
Jian Yan ◽  
Ruth Elgamal ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Cell Survival ◽  
Beta Cells ◽  
High Throughput ◽  
Proinflammatory Cytokines ◽  
Pancreatic Beta Cell ◽  
Regulatory Elements ◽  
A Genome

Beta cells intrinsically contribute to the pathogenesis of type 1 diabetes (T1D), but the genes and molecular processes that mediate beta cell survival in T1D remain largely unknown. We combined high throughput functional genomics and human genetics to identify T1D risk loci regulating genes affecting beta cell survival in response to the proinflammatory cytokines IL-1b, IFNg, and TNFa. We mapped 38,931 cytokine-responsive candidate cis-regulatory elements (cCREs) active in beta cells using ATAC-seq and single nuclear ATAC-seq (snATAC-seq), and linked cytokine-responsive beta cell cCREs to putative target genes using single cell co-accessibility and HiChIP. We performed a genome-wide pooled CRISPR loss-of-function screen in EndoC-betaH1 cells, which identified 867 genes affecting cytokine-induced beta cell loss. Genes that promoted beta cell survival and had up-regulated expression in cytokine exposure were specifically enriched at T1D loci, and these genes were preferentially involved in inhibiting inflammatory response, ubiquitin-mediated proteolysis, mitophagy and autophagy. We identified 2,229 variants in cytokine-responsive beta cell cCREs altering transcription factor (TF) binding using high-throughput SNP-SELEX, and variants altering binding of TF families regulating stress, inflammation and apoptosis were broadly enriched for T1D association. Finally, through integration with genetic fine mapping, we annotated T1D loci regulating beta cell survival in cytokine exposure. At the 16p13 locus, a T1D variant affected TF binding in a cytokine-induced beta cell cCRE that physically interacted with the SOCS1 promoter, and increased SOCS1 activity promoted beta cell survival in cytokine exposure. Together our findings reveal processes and genes acting in beta cells during cytokine exposure that intrinsically modulate risk of T1D.

scholarly journals Investigation of the utility of the 1.1B4 cell as a model human beta cell line for study of persistent enteroviral infection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jessica R. Chaffey ◽  
Jay Young ◽  
Kaiyven A. Leslie ◽  
Katie Partridge ◽  
Pouria Akhbari ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Cell Line ◽  
Beta Cells ◽  
Cell Cultures ◽  
Enteroviral Infection ◽  
Beta Cell Line ◽  
Human Beta Cells ◽  
Human Beta Cell

AbstractThe generation of a human pancreatic beta cell line which reproduces the responses seen in primary beta cells, but is amenable to propagation in culture, has long been an important goal in diabetes research. This is particularly true for studies focussing on the role of enteroviral infection as a potential cause of beta-cell autoimmunity in type 1 diabetes. In the present work we made use of a clonal beta cell line (1.1B4) available from the European Collection of Authenticated Cell Cultures, which had been generated by the fusion of primary human beta-cells with a pancreatic ductal carcinoma cell, PANC-1. Our goal was to study the factors allowing the development and persistence of a chronic enteroviral infection in human beta-cells. Since PANC-1 cells have been reported to support persistent enteroviral infection, the hybrid 1.1B4 cells appeared to offer an ideal vehicle for our studies. In support of this, infection of the cells with a Coxsackie virus isolated originally from the pancreas of a child with type 1 diabetes, CVB4.E2, at a low multiplicity of infection, resulted in the development of a state of persistent infection. Investigation of the molecular mechanisms suggested that this response was facilitated by a number of unexpected outcomes including an apparent failure of the cells to up-regulate certain anti-viral response gene products in response to interferons. However, more detailed exploration revealed that this lack of response was restricted to molecular targets that were either activated by, or detected with, human-selective reagents. By contrast, and to our surprise, the cells were much more responsive to rodent-selective reagents. Using multiple approaches, we then established that populations of 1.1B4 cells are not homogeneous but that they contain a mixture of rodent and human cells. This was true both of our own cell stocks and those held by the European Collection of Authenticated Cell Cultures. In view of this unexpected finding, we developed a strategy to harvest, isolate and expand single cell clones from the heterogeneous population, which allowed us to establish colonies of 1.1B4 cells that were uniquely human (h1.1.B4). However, extensive analysis of the gene expression profiles, immunoreactive insulin content, regulated secretory pathways and the electrophysiological properties of these cells demonstrated that they did not retain the principal characteristics expected of human beta cells. Our data suggest that stocks of 1.1B4 cells should be evaluated carefully prior to their use as a model human beta-cell since they may not retain the phenotype expected of human beta-cells.

scholarly journals Phase II multicentre, double-blind, randomised trial of ustekinumab in adolescents with new-onset type 1 diabetes (USTEK1D): trial protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. e049595
Author(s):  
John W Gregory ◽  
Kymberley Carter ◽  
Wai Yee Cheung ◽  
Gail Holland ◽  
Jane Bowen-Morris ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Research Ethics ◽  
Beta Cells ◽  
Beta Cell Function ◽  
Cell Function ◽  
Double Blind ◽  
C Peptide ◽  
New Onset

IntroductionMost individuals newly diagnosed with type 1 diabetes (T1D) have 10%–20% of beta-cell function remaining at the time of diagnosis. Preservation of residual beta-cell function at diagnosis may improve glycaemic control and reduce longer-term complications.Immunotherapy has the potential to preserve endogenous beta-cell function and thereby improve metabolic control even in poorly compliant individuals. We propose to test ustekinumab (STELARA), a targeted and well-tolerated therapy that may halt T-cell and cytokine-mediated destruction of beta-cells in the pancreas at the time of diagnosis.Methods and analysisThis is a double-blind phase II study to assess the safety and efficacy of ustekinumab in 72 children and adolescents aged 12–18 with new-onset T1D.Participants should have evidence of residual functioning beta-cells (serum C-peptide level >0.2nmol/L in the mixed-meal tolerance test (MMTT) and be positive for at least one islet autoantibody (GAD, IA-2, ZnT8) to be eligible.Participants will be given ustekinumab/placebo subcutaneously at weeks 0, 4 and 12, 20, 28, 36 and 44 in a dose depending on the body weight and will be followed for 12 months after dose 1.MMTTs will be used to measure the efficacy of ustekinumab for preserving C-peptide area under the curve at week 52 compared with placebo. Secondary objectives include further investigations into the efficacy and safety of ustekinumab, patient and parent questionnaires, alternative methods for measuring insulin production and exploratory mechanistic work.Ethics and disseminationThis trial received research ethics approval from the Wales Research Ethics Committee 3 in September 2018 and began recruiting in December 2018.The results will be disseminated using highly accessed, peer-reviewed medical journals and presented at conferences.Trial registration numberISRCTN14274380.

scholarly journals Partners in Crime: Beta-Cells and Autoimmune Responses Complicit in Type 1 Diabetes Pathogenesis

2021 ◽  
Vol 12 ◽  
Author(s):  
Eliana Toren ◽  
KaLia S. Burnette ◽  
Ronadip R. Banerjee ◽  
Chad S. Hunter ◽  
Hubert M. Tse
Keyword(s):  
Type 1 Diabetes ◽  
Immune System ◽  
Beta Cell ◽  
Beta Cells ◽  
Pancreatic Beta Cells ◽  
Disease Etiology ◽  
Autoreactive T Cell ◽  
Beta Cell Heterogeneity ◽  
Beta Cell Response

Type 1 diabetes (T1D) is an autoimmune disease characterized by autoreactive T cell-mediated destruction of insulin-producing pancreatic beta-cells. Loss of beta-cells leads to insulin insufficiency and hyperglycemia, with patients eventually requiring lifelong insulin therapy to maintain normal glycemic control. Since T1D has been historically defined as a disease of immune system dysregulation, there has been little focus on the state and response of beta-cells and how they may also contribute to their own demise. Major hurdles to identifying a cure for T1D include a limited understanding of disease etiology and how functional and transcriptional beta-cell heterogeneity may be involved in disease progression. Recent studies indicate that the beta-cell response is not simply a passive aspect of T1D pathogenesis, but rather an interplay between the beta-cell and the immune system actively contributing to disease. Here, we comprehensively review the current literature describing beta-cell vulnerability, heterogeneity, and contributions to pathophysiology of T1D, how these responses are influenced by autoimmunity, and describe pathways that can potentially be exploited to delay T1D.

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