Project description:Celiac disease (CeD) is an intestinal immune-mediated disorder caused by gluten ingestion in genetically predisposed subjects. CeD is characterized by villous atrophy, altered intestinal permeability, crypt hyperplasia and innate and adaptive immune response. This study aimed to develop and validate the use of intestinal organoids from celiac patients to study CeD. A repository of organoids from duodenum of non-celiac and celiac patients was generated and characterized accordingly to standard procedures. RNA-seq analysis was employed to study the global gene expression program of CeD (n=3) and non-CeD (n=3) organoids sets. While the three celiac derived organoids shared similar transcriptional signatures the NC samples set appeared more heterogeneous. We found 486 genes differentially expressed between the two groups. Of them, 299 genes were downregulated (FC<2; FDR<0.05) and 187 were upregulated in CeD (FC >2; FDR<0.05). We observed CeD organoids had significantly altered expression of genes associated with barrier function, innate immunity, and stem cell function.
Project description:In vitro models of autoimmunity are constrained by an inability to culture affected epithelium alongside the complex tissue-resident immune microenvironment. Celiac disease (CeD) is an autoimmune disease where dietary gluten-derived peptides bind the MHC- II molecules HLA-DQ2 or -DQ8 to initiate immune-mediated duodenal mucosal injury. Here, we generated air-liquid interface (ALI) duodenal organoids from endoscopic biopsies that preserve epithelium alongside native mesenchyme and tissue-resident immune cells as a unit without requiring reconstitution. The ALI organoid immune diversity spanned T, B, plasma, NK and myeloid cells with extensive T and B cell receptor repertoires. HLA-DQ2.5-restricted gluten peptides selectively instigated epithelial destruction in HLA-DQ2.5-expressing CeD patient organoids, which was antagonized by MHC-II or NKG2C/D blockade. Gluten epitopes stimulated a CeD organoid network response in lymphoid and myeloid subsets alongside anti-TG2 autoantibody production. Functional studies in CeD organoids revealed IL-7 as a novel gluten-inducible pathogenic modulator which regulated CD8+ T cell-NKG2C/D expression and was necessary and sufficient for epithelial destruction. Further, endogenous IL-7 was markedly induced in patient biopsies from active CeD versus remission disease, predominantly in lamina propria mesenchyme. By preserving epithelium alongside diverse immune populations, this human in vitro CeD model recapitulates gluten-dependent pathology, facilitates mechanistic investigation, and establishes proof-of-principle for organoid modeling of autoimmunity.
Project description:The pathogenesis of celiac disease (CeD) remains incompletely understood. Traditional diagnostic techniques for CeD include serological testing and endoscopic examination; however, they have limitations. Therefore, there is a need to identify novel noninvasive biomarkers for CeD diagnosis. We analyzed duodenal and plasma samples from CeD patients by four-dimensional data-dependent acquisition (4D-DIA) proteomics. Differentially expressed proteins (DEPs) were identified for functional analysis and to propose blood biomarkers associated with CeD diagnosis. In duodenal and plasma samples, respectively, 897 and 140 DEPs were identified. Combining weighted gene co-expression network analysis(WGCNA) with the DEPs, five key proteins were identified across three machine learning methods. FGL2 and TXNDC5 were significantly elevated in the CeD group, while CHGA expression showed an increasing trend, but without statistical significance. The receiver operating characteristic curve results indicated an area under the curve (AUC) of 0.7711 for FGL2 and 0.6978 for TXNDC5, with a combined AUC of 0.8944. Exploratory analysis using Mfuzz and three machine learning methods identified four plasma proteins potentially associated with CeD pathological grading (Marsh classification): FABP, CPOX, BHMT, and PPP2CB. We conclude that FGL2 and TXNDC5 deserve exploration as potential sensitive, noninvasive diagnostic biomarkers for CeD.
Project description:For celiac disease (CeD) the diagnosis and response to treatment is determined by histological evaluation of gut biopsies which depend on proper biopsy orientation and has poor inter-observer reproducibility. Biopsy proteome measurement that reports on the tissue state can be obtained by mass spectrometry (MS) analysis of formalin-fixed paraffin embedded (FFPE) tissue. Here we aimed to transform biopsy proteome data into numerical scores that would give observer-independent measures of mucosal remodeling in CeD. A pipeline was established that employs glass-mounted FFPE sections for MS-based proteome analysis. Proteome data was converted to a numerical score using two different approaches, by calculating a rank-based enrichment score and by training a machine-learning algorithm to calculate a disease-state prediction value. The scoring approaches were compared to each other and to histology using a validation cohort of 18 CeD patients comparing biopsies collected before and after treatment with gluten-free diet (GFD). Biopsies from non-CeD individuals (n = 18) served as controls.
Project description:The common gamma chain (γc) is required for productive signaling by interleukin (IL)-15, IL-21 and IL-2, which are critically involved in immune activation and regulation. IL-21 and IL-15 are implicated in the pathogenesis of type-1 diabetes, graft-versus-host disease, and celiac disease (CeD), a gluten-mediated autoimmune-like enteropathy. Attempts to treat type-1 diabetes and graft-versus-host disease with biologics targeting one particular cytokine have failed. Both IL-15 and IL-21 have been suggested to drive activation of cytotoxic T cells (CTL) that are the effectors mediating tissue destruction in CeD and organ-specific autoimmune disorders. We show that the concomitant upregulation of IL-15 and IL-21 occurs only in full-blown CeD with villous atrophy. BNZ-2, a peptide that targets the γc, was able to block the cooperative IL-15/IL-21 mediated transcriptional activation of human tissue-resident intraepithelial CTL. Importantly, this inhibition was specific and did not interfere with IL-2 signaling, a cytokine with known immunoregulatory functions. Moreover, BNZ-2 blocked gluten-induced IFN-γ production in small intestinal organ cultures from CeD patients. These observations identify BNZ-2 as a therapeutic candidate for immune disorders in which IL-15 and IL-21 cooperate to induce CTL-mediated tissue damage.
Project description:Celiac disease (CeD) is a food sensitivity characterized by a breakdown of oral tolerance to gluten proteins in genetically predisposed individuals, although the underlying mechanisms are incompletely understood. To evaluate a functional role of bacterial proteases in CeD, we colonized germ-free or clean SPF mice with P.aeruginosa PA14 or P.aeruginosa PA14 disrupted in lasB gene (elastase). We show gluten-independent, PAR-2 mediated upregulation of inflammatory pathways by LasB in C57BL/6 mice without villus blunting. In mice expressing CeD risk genes, P. aeruginosa elastase synergized with gluten to induce more severe inflammation that was associated with moderate villus blunting.
Project description:The prevailing theory of autoimmune disease, that the body creates autoantibodies that attack “self,” was developed during an era when culture-based methods vastly underestimated the number of microbes capable of persisting in and on Homo sapiens. Thanks to the advent of culture-independent tools, the human body is now known to harbor billions of microbes whose collective genomes work in concert with the human genome. Thus, the human genome can no longer be studied in isolation. Some of these microbes persist by slowing the activity of the vitamin D receptor nuclear receptor, affecting the expression of endogenous antimicrobials and other key components of the innate immune system. It seems that bacteria that cause autoimmune disease accumulate over a lifetime, with individuals picking up pathogens with greater ease over time, as the immune response becomes increasingly compromised. Any one autoimmune disease is likely due to many different microbes within the metagenomic microbiota. This helps explain the high levels of comorbidity observed among patients with autoimmune conditions. What are commonly believed to be autoantibodies may instead be created in response to this metagenomic microbiota when the adaptive immune system is forced to deal with disintegration of infected cells. Similarly, haplotypes associated with autoimmune conditions vary widely among individuals and populations. They are more suggestive of a regional infectious model rather than a model in which an illness is caused by inherited variation of HLA haplotypes
Project description:We have shown that worms that possess mutations in two electron transport chain subunits live longer due to mtROS signalling. Wild type worms can also live longer by treatment with the pro-oxidant paraquat. Paraquat treatment is not additive to the mutations in the ETC subunits. We aimed to determine the underlying changes in gene expression that were common to both paraquat treatment and the two mutations. We also have shown genetically that the mtROS signal that leads to extended lifespan is dependent on CED-4. We generated double mutants that lack functional CED-4 with the two mutations in the ETC subunits. We have found that a large number of gene expression changes by mtROS signalling are reverted by loss of CED-4. Young adult C. elegans were grown using a 4-hour synchronized lay and harvested by hand picking. At least three biological repeats were obtained for each condition. Worm RNA was extracted and prepared for hybridization to Affymetrix chips. We compared the gene expression patterns of genetic mutants and the wild type treated with paraquat all against a wild type control. We sought to obtain a common pattern of expression between two genetic mutants, isp-1 and nuo-6, and paraquat treatment.