Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Loss of function of XBP1 splicing activity of IRE1a favors B cell tolerance breakdown

ABSTRACT: Tolerance breakdown leads to the development of autoimmune diseases in an increasing manner. B cells strongly contribute to the pathogenesis of these diseases, notably via the production of autoantibodies leading to cell depletion, receptor modulation and organ damages. However, the molecular mechanisms of B cell tolerance breakdown are badly known. Autoimmune diseases are frequently aggregated in families in two or more generations. The study of these familial forms could therefore help to better describe common biological mechanisms leading to B cell tolerance breakdown. By Whole-Exome Sequencing, we describe here in a multiplex family with several members presenting autoantibody-mediated autoimmunity a new heterozygous mutation (p.R594C) in ERN1 gene, coding for IRE1α. Using human cell lines and a knock-in (KI) transgenic mouse model, we showed that this mutation leads to a profound defect of IRE1α ribonuclease activity on XBP1 splicing. The KI mice developed a broad panel of autoantibodies, however in a subclinical manner. These results suggest that a decrease of XBP1s production could contribute to B cell tolerance breakdown and give new insights into the function of IRE1α which are important to consider for the development or IRE1α targeting strategies.

ORGANISM(S): Mus musculus

PROVIDER: GSE234812 | GEO | 2023/11/20

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

CXCR5+PD-1+CD8+ T cells are a novel T helper cell sublineage and are negatively regulated by Stat5 [scRNA-Seq]

Project description:Many autoimmune diseases are characterized by the production of autoantibodies. The current view is that CD4+ Tfh cells are the main subset regulating autoreactive B cells. Here, we discover a distinct novel CXCR5+PD1+ Tfh subset of CD8+ T cells whose development and function are negatively regulated by Stat5. These CD8+ Tfh cells regulate the GC B cell response and control autoantibody production. Deficiency of Stat5 in CD8+ T cells leads to an increase of CD8+ Tfh cells, resulting in the breakdown of B cell tolerance and autoantibody production. CD8+ Tfh share similar gene signatures with CD4+ Tfh and require CD40L/CD40 and TCR/MHCI interactions to deliver help to B cells. Our study highlights the diversity of follicular T cell subsets that contribute to the breakdown of B-cell tolerance

2019-08-30 | GSE136641 | GEO

CXCR5+PD-1+CD8+ T cells are a distinct sublineage of CD8+ Tfh cells and Stat5 suppresses the expression of the Tfh-specific genes in CXCR5+PD-1+CD8+ T cells [RNA-Seq]

Project description:Many autoimmune diseases are characterized by the production of autoantibodies. The current view is that CD4+ Tfh cells are the main subset regulating autoreactive B cells. Here, we discover a novel CXCR5+PD1+ Tfh subset of CD8+ T cells whose development and function are negatively regulated by Stat5. These CD8+ Tfh cells regulate the GC B cell response and control autoantibody production. Deficiency of Stat5 in CD8+ T cells leads to an increase of CD8+ Tfh cells, resulting in the breakdown of B cell tolerance and autoantibody production. CD8+ Tfh cells share similar gene signatures with CD4+ Tfh cells and require CD40L/CD40 and TCR/MHCI interactions to deliver help to B cells. Our study highlights the diversity of follicular T cell subsets that contribute to the breakdown of B-cell tolerance

2019-08-30 | GSE136640 | GEO

Expression data from thymic epithelial cells of 5-6 weeks old C57BL/6J mice.

Project description:Defects in thymic epithelial cell development causes autoimmune diseases due to breakdown of central tolerance, including skin inflammation. IKKa may be essential to link central tolerance to skin inflammation. We used microarrays to examine the global gene expression with or without kinase inactive IKKa, and identified a distinct set of down-regulated genes in the presence of kinase-dead IKKa in thymic epithelial cells.

2017-04-01 | GSE52137 | GEO

TLR7 gene duplication accelerates autoimmunity and promotes nucleolar-specific B cells

Project description:Systemic autoimmune diseases such as lupus and scleroderma are characterized by the loss of tolerance to nuclear antigens, but the mechanisms by which specific autoantibodies are selected are unclear. Here we report that B cells containing the Y-linked autoimmune accelerator (Yaa) locus are intrinsically biased towards nucleolar antigens due to a duplication of TLR genes in the pseudoautosomal region that makes them more responsive to TLR7 ligands and augments the Btk-dependent signaling pathway. These findings provide genetic evidence that naturally occurring differences in expression of TLR7 have a dramatic impact on antigen selection in autoimmunity. Keywords: genetic modification, Yaa locus

2006-06-01 | GSE4445 | GEO

Targeting hepatic IRE1a for Treating GDF15-driven Anorexia in Chemotherapy

Project description:Anorexia and other side effects of chemotherapy significantly limit the clinical applications of these chemotherapeutic agents, with underlying mechanisms still unclear. A growing body of research reveals that elevated levels of circulating GDF15 after chemotherapy are essential in initiating anorexia and other side effects by activating GFRAL+ neurons in the brainstem. However, the full array of context-dependent transcriptional regulators controlling Gdf15 expression remains to be defined. This study reports that chemotherapy drugs acutely stimulate liver GDF15 production via selective activation of the hepatic stress sensor IRE1α, thereby controlling circulating GDF15 levels. Genetic ablation of hepatic IRE1α reduces circulating GDF15 and alleviates anorexia and body weight loss following chemotherapy drug treatments in tumor-bearing mice. Mechanistically, chemotherapy drugs activate hepatic IRE1α RNase activity to produce the active form of the transcription factor XBP1 to promotes the expression of Gdf15 gene in hepatocytes. Moreover, treatment with pharmacological IRE1α RNase inhibitor effectively suppresses liver Gdf15 expression and circulating GDF15 levels, resulting in improvements in chemotherapy-induced anorexia and body weight loss. Our results reveal a stress-responsive mechanism that mediates communication between the liver and brain. This mechanism can be targeted pharmacologically to alleviate anorexic side effects that accompany chemotherapy-induced body weight loss.

2024-04-22 | GSE235695 | GEO

TLR7 gene duplication accelerates autoimmunity and promotes nucleolar-specific B cells

2010-07-01 | E-GEOD-4445 | biostudies-arrayexpress

The IRE1α/XBP1 pathway expression is impaired in pediatric cholestatic liver disease explants

Project description:Background/Aims: Cholestatic liver diseases (CLD) are the leading indication for pediatric liver transplantation. Increased intrahepatic bile acid concentrations cause endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) is activated to maintain homeostasis. UPR dysregulation, including the inositol-requiring enzyme 1α/X-box protein 1 (IRE1α/XBP1) pathway, is associated with several adult liver diseases. We evaluated hepatic UPR expression in pediatric patients with end-stage CLD and hypothesize that an inability to appropriately activate the hepatic IRE1α/XBP1 pathway is associated with the pathogenesis of CLD. Methods: We evaluated 34 human liver explants. Cohorts included: pediatric CLD (Alagille, ALGS, and progressive familial intrahepatic cholestasis, PFIC), pediatric non-cholestatic liver disease controls (autoimmune hepatitis, AIH), adult CLD, and normal controls. We performed RNA-seq, quantitative PCR, and western blotting to measure expression differences of the hepatic UPR and other signaling pathways. Results: Metascape pathway analysis demonstrated that the KEGG ‘protein processing in ER’ pathway was downregulated in pediatric CLD compared to normal controls. Pediatric CLD had decreased hepatic IRE1α/XBP1 pathway gene expression and decreased protein expression of p-IRE1α compared to normal controls. These CLD changes were not disease-specific to ALGS or PFIC. IRE1α/XBP1 pathway gene expression was decreased in pediatric CLD compared to AIH disease controls. Conclusion: Pediatric CLD explants have decreased gene and protein expression of the protective IRE1α/XBP1 pathway and down-regulated KEGG protein processing in the ER pathways. IRE1α/XBP1 pathway expression differences occur when compared to both normal and non-cholestatic disease controls. Attenuated expression of the IRE1α/XBP1 pathway is associated with cholestatic diseases and could be targeted to treat pediatric CLD.

2022-06-23 | GSE206364 | GEO

BAFF neutralization impairs the clearance of dead adipocytes and promotes insulin resistance in obese mice

Project description:B cell-activating factor (BAFF) is critical for the survival and maturation of B2 cells. However, excess BAFF breaks the peripheral tolerance of B2-cells leading to the production of autoantibodies that cause autoimmune diseases. During obesity, BAFF is predominantly produced by white adipose tissue (WAT), and IgG autoantibodies against adipocytes are identified in the WAT of obese humans. However, it remains to be determined if the autoantibodies formed during obesity affect WAT remodeling and systemic insulin resistance. Here, we show that IgGs from high-fat diet (HFD)-induced obese mice bind to apoptotic adipocytes and promote their clearance by macrophages. Next, using murine models of obesity in which the gonadal WAT undergoes remodeling, unexpectedly we found that BAFF neutralization increased the number of dead adipocytes and exacerbated WAT inflammation and insulin resistance despite depletion of IgG autoantibodies. RNA sequencing of the stromal vascular fraction from the WAT revealed impaired B cell activation and phagocytosis pathways. In-vitro, the clearance of apoptotic adipocytes by macrophages was attenuated in the presence of IgGs from BAFF-neutralized mice compared to the control mice. Altogether, our study suggests a beneficial role of BAFF and IgG autoantibodies in WAT remodeling in obesity and the regulation of systemic insulin resistance.

2024-08-28 | GSE255950 | GEO

Chronic Activation of pDCs in Autoimmunity is linked to Dysregulated ER Stress and Metabolic Responses

Project description:Plasmacytoid dendritic cells (pDCs) chronically produce type I interferon (IFN-I) in multiple autoimmune diseases, such as systemic sclerosis (SSc) and systemic lupus erythematosus (SLE). Here, we report that the IRE1α-XBP1 branch of the unfolded protein response (UPR) inhibits the production of IFN-α by TLR7- or TLR9-activated pDCs. In SSc patients, pDCs demonstrated reduced expression of UPR marker genes, which inversely correlated with the levels of IFN-I-stimulated genes. CXCL4, a chemokine that is elevated in SSc patients, downregulated IRE1α-XBP1-controlled genes and promoted IFN-α production by pDCs. Mechanistically, IRE1α-XBP1 activation rewired glycolysis to serine biosynthesis by inducing phosphoglycerate dehydrogenase (PHGDH) expression. This process reduced pyruvate access to the tricarboxylic acid (TCA) cycle and blunted mitochondrial ATP generation and cAMP signaling, which are essential for pDC IFN-I responses. Notably, PHGDH expression was reduced in pDCs from patients with SSc and SLE, and pharmacological blockade of TCA cycle reactions inhibited IFN-I responses in pDCs from these patients. Hence, modulating the IRE1α-XBP1-PHGDH axis may represent a hitherto unexplored strategy for alleviating chronic pDC activation in autoimmune disorders.

2022-08-15 | GSE211230 | GEO

Gene expression in Bach2-deficient and wildtype CD4 single-positive thymocytes from mixed chimeric animals

Project description:The role of FoxP3+ regulatory T (Treg) cells in the maintenance of immunological tolerance is well established. Recently, genome-wide association studies (GWAS) in humans have associated polymorphisms within the BACH2 locus encoding the transcription factor BTB and CNC homology 1, basic leucine zipper transcription factor 2 (Bach2) with diverse allergic and autoimmune diseases including asthma, multiple sclerosis, Crohn's disease, celiac disease, generalized vitiligo and type 1 diabetes. Common to these diseases is a failure to adequately maintain immunological tolerance. However, a role for Bach2 in this process has not been established. Here, by assessing the phenotype of mice in which the Bach2 gene is disrupted, we demonstrate a non-redundant role for Bach2 in the prevention of a spontaneous lethal inflammatory disorder predominantly affecting the lung and gut with excessive T helper 2 (Th2) responses and formation of circulating autoantibodies. Bach2 was necessary for efficient induction of FoxP3 expression both during thymopoesis and upon stimulation of naïve peripheral CD4+ T cells under Treg polarizing conditions in vitro. Consequently, in bone marrow reconstitution experiments, Bach2 expression within the haematopoetic system was necessary for suppression of lethal autoimmunity in a manner that was FoxP3 dependent. These findings demonstrate a requirement for Bach2 in early lineage commitment of both thymic and induced Treg cells and point to shared mechanisms that underlie diverse allergic and autoimmune disorders that may serve as targets in the development of novel therapeutic strategies. Six samples were collected from separate mice: three Ly5.1+ wildtype thymocyte samples (biological replicates) and three Ly5.1- Bach2 knockout thymocyte samples (biological replicates).

2013-11-01 | E-GEOD-42598 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data