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1.
  • Bergemalm, Daniel, 1977-, et al. (author)
  • Systemic Inflammation in Preclinical Ulcerative Colitis
  • 2021
  • In: Gastroenterology. - : AGA Institute. - 0016-5085 .- 1528-0012. ; 161:5, s. 1526-1539.e9
  • Journal article (peer-reviewed)abstract
    • Background & Aims: Preclinical ulcerative colitis is poorly defined. We aimed to characterize the preclinical systemic inflammation in ulcerative colitis, using a comprehensive set of proteins.Methods: We obtained plasma samples biobanked from individuals who developed ulcerative colitis later in life (n = 72) and matched healthy controls (n = 140) within a population-based screening cohort. We measured 92 proteins related to inflammation using a proximity extension assay. The biologic relevance of these findings was validated in an inception cohort of patients with ulcerative colitis (n = 101) and healthy controls (n = 50). To examine the influence of genetic and environmental factors on these markers, a cohort of healthy twin siblings of patients with ulcerative colitis (n = 41) and matched healthy controls (n = 37) were explored.Results: Six proteins (MMP10, CXCL9, CCL11, SLAMF1, CXCL11 and MCP-1) were up-regulated (P < .05) in preclinical ulcerative colitis compared with controls based on both univariate and multivariable models. Ingenuity Pathway Analyses identified several potential key regulators, including interleukin-1β, tumor necrosis factor, interferon-gamma, oncostatin M, nuclear factor-κB, interleukin-6, and interleukin-4. For validation, we built a multivariable model to predict disease in the inception cohort. The model discriminated treatment-naïve patients with ulcerative colitis from controls with leave-one-out cross-validation (area under the curve = 0.92). Consistently, MMP10, CXCL9, CXCL11, and MCP-1, but not CCL11 and SLAMF1, were significantly up-regulated among the healthy twin siblings, even though their relative abundances seemed higher in incident ulcerative colitis.Conclusions: A set of inflammatory proteins are up-regulated several years before a diagnosis of ulcerative colitis. These proteins were highly predictive of an ulcerative colitis diagnosis, and some seemed to be up-regulated already at exposure to genetic and environmental risk factors.
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  • Chen, Jie, et al. (author)
  • Bidirectional Mendelian Randomisation Analysis Provides Evidence for the Causal Involvement of Dysregulation of CXCL9, CCL11 and CASP8 in the Pathogenesis of Ulcerative Colitis
  • 2023
  • In: Journal of Crohn's & Colitis. - : Oxford University Press. - 1873-9946 .- 1876-4479. ; 17:5, s. 777-785
  • Journal article (peer-reviewed)abstract
    • Background and Aims Systemic inflammation is well recognised to be associated with ulcerative colitis [UC], but whether these effects are causal or consequential remains unclear. We aimed to define potential causal relationship of cytokine dysregulation with different tiers of evidence. Methods We first synthesised serum proteomic profiling data from two multicentred observational studies, in which a panel of systemic inflammatory proteins was analysed to examine their associations with UC risk. To further dissect observed associations, we then performed a bidirectional two-sample Mendelian randomisation [TSMR] analysis from both forward and reverse directions using five genome-wide association study [GWAS] summary level data for serum proteomic profiles and the largest GWAS of 28 738 European-ancestry individuals for UC risk. Results Pooled analysis of serum proteomic data identified 14 proteins to be associated with the risk of UC. Forward MR analysis using only cis-acting protein quantitative trait loci [cis-pQTLs] or trans-pQTLs further validated causal associations of two chemokines and the increased risk of UC: C-X-C motif chemokine ligand 9 [CXCL9] [OR 1.45, 95% CI 1.08, 1.95, p = 0.012] and C-C motif chemokine ligand 11 [CCL11] [OR 1.14, 95% CI 1.09, 1.18, p = 3.89 x 10(-10)]. Using both cis- and trans-acting pQTLs, an association of caspase-8 [CASP8] [OR 1.04, 95% CI 1.03, 1.05, p = 7.63 x 10(-19)] was additionally identified. Reverse MR did not find any influence of genetic predisposition to UC on any of these three inflammation proteins. Conclusion Pre-existing elevated levels of CXCL9, CCL11 and CASP8 may play a role in the pathogenesis of UC.
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  • Kalla, Rahul, et al. (author)
  • EPIGENETIC ALTERATIONS IN IBD : DEFINING GEOGRAPHICAL, GENETIC, AND IMMUNEIN-FLAMMATORY INFLUENCES ON THE CIRCULATING METHYLOME
  • 2021
  • In: Gut. - : BMJ Publishing Group Ltd. - 0017-5749 .- 1468-3288. ; 70:Suppl. 4, s. A5-A5
  • Journal article (other academic/artistic)abstract
    • Introduction: DNA methylation may provide critical insights into gene-environment interactions in inflammatory bowel disease (IBD).Methods: Using the multi-centre IBD Character inception cohort (295 controls, 154 CD, 161 UC, 28 IBD-U), epigenome-wide methylation was profiled using Illumina HumanMethylation450 platform. Differentially methylated position analysis was performed using age, sex and cell proportions as covariates. Integration of paired genomic and transcriptomic layers was done with Multi-Omics Factor Analysis v2 (MOFA). Unsupervised principal component analyses were performed to examine correlates of treatment escalation and clinical predictors of disease severity.Results: We report 137 differentially methylated positions (DMP) in whole blood in IBD, including VMP1/MIR21 (p=9.11×10-15) and RPS6KA2 (6.43×10-13); with consistency seen across Scandinavia and UK. Cell of origin analysis preferentially implicated the monocyte lineage. Dysregulated loci demonstrate strong genetic influence, notably VMP1 (p=1.53×10-15). Age acceleration is seen in IBD (coefficient 0.94, p<2.2x10-16). Several immuno-active genes demonstrated highly significant correlations between methylation and gene expression in IBD, in particular OSM: IBD r -0.32, p 3.64×10-7 vs. non-IBD r -0.14, p=0.77). Multi-omic integration of methylome, genome and transcriptome also identified specific pathways that associate with immune activation, response and regulation at disease inception. At follow up, a signature of 3 DMPs (TAP1, TESPA1, RPTOR) associated with treatment escalation to biological agents or surgery (hazard ratio of 5.19 (CI:2.14-12.56, logrank p=9.70×10-4).Conclusion: This study highlights the stability of the IBD-specific circulating methylome across regions with shared ancestry. Through integrative multi-omic analyses we identify key pro-inflammatory genes that are upregulated in IBD at inception. Furthermore, differential methylation within certain genes such as TAP1 associate with disease course over time.
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  • Nowak, Jan Krzysztof, et al. (author)
  • Age, Inflammation, and Disease Location Are Critical Determinants of Intestinal Expression of SARS-CoV-2 Receptor ACE2 and TMPRSS2 in Inflammatory Bowel Disease
  • 2020
  • In: Gastroenterology. - : American Gastroenterology Association Institute. - 0016-5085 .- 1528-0012. ; 159:3, s. 1151-1154
  • Journal article (other academic/artistic)abstract
    • Although the respiratory tract is implicated as the primary portal of entry of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), gastrointestinal involvement is well-reported, associated with nausea, vomiting, diarrhea, and highly persistent viral particle shedding in feces.(1,2)There is critical need to establish factors determining susceptibility to Coronavirus Disease 2019 (COVID-19) in patients with inflammatory bowel disease (IBD). Age, comorbidity, disease activity, and exposure to immunomodulatory and biological therapies provide the basis for new guidelines for risk stratification and shielding.(3)We hypothesize that expression levels of the SARS-CoV-2 spike protein receptor, angiotensin-converting enzyme 2 (ACE2),(4) may also determine susceptibility to SARS-CoV-2-inflicted damage. Transmembrane serine protease 2 (TMPRSS2) primes the viral spike protein,(5) allowing for the potent binding of ACE2. Both are known to be highly expressed in healthy ileal epithelium, with lower levels in epithelial cells in the colon. We report dysregulated mucosal ACE2 and TMPRSS2 expression in the colon and ileum in IBD, and identify the critical determinants of altered expression.
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8.
  • Nowak, Jan K., et al. (author)
  • Characterization of the circulating transcriptomic landscape in inflammatory bowel disease provides evidence for dysregulation of multiple transcription factors including NFE2, SPI1, CEBPB, and IRF2
  • 2022
  • In: Journal of Crohn's & Colitis. - : Oxford University Press. - 1873-9946 .- 1876-4479. ; 16:8, s. 1255-1268
  • Journal article (peer-reviewed)abstract
    • AIM: To assess the pathobiological and translational importance of whole blood transcriptomic analysis in inflammatory bowel disease (IBD).METHODS: We analyzed whole blood expression profiles from paired-end sequencing in a discovery cohort of 590 Europeans recruited across six countries in the IBD Character initiative (newly diagnosed patients with Crohn's disease [CD, n = 156], ulcerative colitis [UC, n = 167], and controls [n = 267]), exploring differential expression (DESeq2), co-expression networks (WGCNA), and transcription factor involvement (EPEE, ChEA, DoRothEA). Findings were validated by analysis of an independent replication cohort (99 CD, 100 UC, and 95 controls). In the discovery cohort, we also defined baseline expression correlates of future treatment escalation using cross-validated elastic-net and random forest modelling, along with a pragmatic ratio detection procedure.RESULTS: Disease-specific transcriptomes were defined in IBD (8697 transcripts), CD (7152), and UC (8521), with the most highly significant changes in single genes, including CD177 (log2-fold change [LFC] = 4.63, p = 4.05 × 10 -118), MCEMP1 (LFC = 2.45, p = 7.37 × 10 -109), and S100A12 (LFC = 2.31, p = 2.15 × 10 -93). Significantly over-represented pathways included IL-1 (p = 1.58 × 10 -11), IL-4, and IL-13 (p = 8.96 × 10 -9). Highly concordant results were obtained using multiple regulatory activity inference tools applied to the discovery and replication cohorts. These analyses demonstrated central roles in IBD for the transcription factors NFE2, SPI1 (PU.1), CEBPB, and IRF2, all regulators of cytokine signaling, based on a consistent signal across cohorts and transcription factor ranking methods. A number of simple transcriptome-based models were associated with the need for treatment escalation, including the binary CLEC5A/CDH2 expression ratio in UC (hazard ratio = 23.4, 95% CI 5.3-102.0).CONCLUSION: Transcriptomic analysis has allowed for a detailed characterization of IBD pathobiology, with important potential translational implications.
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9.
  • Olbjern, Christine, et al. (author)
  • Fecal microbiota profiles in treatment-naive pediatric inflammatory bowel disease : associations with disease phenotype, treatment, and outcome
  • 2019
  • In: Clinical and Experimental Gastroenterology. - Macclesfield, United Kingdom : DOVE MEDICAL PRESS LTD. - 1178-7023. ; 12, s. 37-49
  • Journal article (peer-reviewed)abstract
    • Purpose: Imbalance in the microbiota, dysbiosis, has been identified in inflammatory bowel disease (IBD). We explored the fecal microbiota in pediatric patients with treatment-naive IBD, non-IBD patients with gastrointestinal symptoms and healthy children, its relation to IBD subgroups, and treatment outcomes. Patients and methods: Fecal samples were collected from 235 children below 18 years of age. Eighty children had Crohns disease (CD), 27 ulcerative colitis (UC), 3 IBD unclassified, 50 were non-IBD symptomatic patients, and 75 were healthy. The bacterial abundance of 54 predefined DNA markers was measured with a 16S rRNA DNA-based test using GA-Map (TM) technology at diagnosis and after therapy in IBD patients. Results: Bacterial abundance was similarly reduced in IBD and non-IBD patients in 51 of 54 markers compared to healthy patients (Pamp;lt;0.001). Only Prevotella was more abundant in patients (Pamp;lt;0.01). IBD patients with ileocolitis or total colitis had more Ruminococcus gnavus (P=0.02) than patients with colonic CD or left-sided UC. CD patients with upper gastrointestinal manifestations had higher Veillonella abundance (Pamp;lt;0.01). IBD patients (58%) who received biologic therapy had lower baseline Firmicutes and Mycoplasma hominis abundance (Pamp;lt;0.01) than conventionally treated. High Proteobacteria abundance was associated with stricturing/penetrating CD, surgery (Pamp;lt;0.01), and nonmucosal healing (Pamp;lt;0.03). Low Faecalibacterium prausnitzii abundance was associated with prior antibiotic therapy (P=0.001), surgery (P=0.02), and nonmucosal healing (Pamp;lt;0.03). After therapy, IBD patients had unchanged dysbiosis. Conclusion: Fecal microbiota profiles differentiated IBD and non-IBD symptomatic children from healthy children, but displayed similar dysbiosis in IBD and non-IBD symptomatic patients. Pretreatment fecal microbiota profiles may be of prognostic value and aid in treatment individualization in pediatric IBD as severe dysbiosis was associated with an extensive, complicated phenotype, biologic therapy, and nonmucosal healing. The dysbiosis persisted after therapy, regardless of treatments and mucosal healing.
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  • Shubhakar, Archana, et al. (author)
  • Serum N-Glycomic Biomarkers Predict Treatment Escalation in Inflammatory Bowel Disease
  • 2023
  • In: Journal of Crohn's & Colitis. - : Oxford University Press. - 1873-9946 .- 1876-4479. ; 17:6, s. 919-932
  • Journal article (peer-reviewed)abstract
    • Biomarkers to guide clinical decision-making at diagnosis of inflammatory bowel disease (IBD) are urgently needed. We investigated a composite serum N-glycomic biomarker to predict future disease course in a discovery cohort of 244 newly diagnosed IBD patients. Forty-seven individual glycan peaks were analysed using ultra-high performance liquid chromatography identifying 105 glycoforms from which 24 derived glycan traits were calculated. Multivariable logistic regression was performed to determine associations of derived glycan traits with disease. Cox proportional hazard models were used to predict treatment escalation from first-line treatment to biologics or surgery (hazard ratio (HR) 25.9, p=1.1×10-12; 95% confidence interval (CI), 8.52-78.78). Application to an independent replication cohort of 54 IBD patients yielded a HR of 5.1 (p=1.1×10-5; 95% CI, 2.54-10.1). These data demonstrate the prognostic capacity of serum N-glycan biomarkers and represent a step towards personalized medicine in IBD.
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11.
  • Sun, Yuhao, et al. (author)
  • The Contribution of Genetic Risk and Lifestyle Factors in the Development of Adult-Onset Inflammatory Bowel Disease : A Prospective Cohort Study
  • 2023
  • In: American Journal of Gastroenterology. - : Lippincott Williams & Wilkins. - 0002-9270 .- 1572-0241. ; 118:3, s. 511-522
  • Journal article (peer-reviewed)abstract
    • INTRODUCTION: The joint associations across genetic risk, modifiable lifestyle factors, and inflammatory bowel disease (IBD) remains unclear.METHODS: Genetic susceptibility to Crohn's disease (CD) and ulcerative colitis (UC) was estimated by polygenic risk scores and further categorized into high, intermediate, and low genetic risk categories. Weighted healthy lifestyle scores were constructed based on 5 common lifestyle factors and categorized into favorable (4 or 5 healthy lifestyle factors), intermediate (3 healthy lifestyle factors), and unfavorable (0-2 healthy lifestyle factors) groups. Cox proportional hazards regression model was used to estimate the hazard ratios (HR) and 95% confidence interval (CI) for their associations.RESULTS: During the 12-year follow-up, 707 cases with CD and 1576 cases with UC were diagnosed in the UK Biobank cohort. Genetic risk and unhealthy lifestyle categories were monotonically associated with CD and UC risk with no multiplicative interaction between them. The HR of CD and UC were 2.24 (95% CI 1.75-2.86) and 2.15 (95% CI 1.82-2.53) for those with a high genetic risk, respectively. The HR of CD and UC for individuals with an unfavorable lifestyle were 1.94 (95% CI 1.61-2.33) and 1.98 (95% CI 1.73-2.27), respectively. The HR of individuals with a high genetic risk but a favorable lifestyle (2.33, 95% CI 1.58-3.44 for CD, and 2.05, 95% CI 1.58-2.66 for UC) were reduced nearly by half, compared with those with a high genetic risk but an unfavorable lifestyle (4.40, 95% CI 2.91-6.66 for CD and 4.44, 95% CI 3.34-5.91 for UC).DISCUSSION: Genetic and lifestyle factors were independently associated with susceptibility to incident CD and UC. Adherence to a favorable lifestyle was associated with a nearly 50% lower risk of CD and UC among participants at a high genetic risk.
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12.
  • Vatn, Simen Svendsen, et al. (author)
  • Mucosal Gene Transcript Signatures in Treatment Naïve Inflammatory Bowel Disease : A Comparative Analysis of Disease to Symptomatic and Healthy Controls in the European IBD-Character Cohort
  • 2022
  • In: Clinical and Experimental Gastroenterology. - : Dove Medical Press Ltd.. - 1178-7023. ; 15, s. 5-25
  • Journal article (peer-reviewed)abstract
    • Background: Studies of the mucosal transcriptomic landscape have given new insight into the pathogenesis of inflammatory bowel disease (IBD). Recently, the predictive biomarker potential of gene expression signatures has been explored. To further investigate the mucosal gene expression in IBD, we recruited a cohort of treatment naïve patients and compared them to both symptomatic and healthy controls.Methods: Altogether, 323 subjects were included: Crohn's disease (N = 75), ulcerative colitis (N = 87) and IBD unclassified (N = 3). Additionally, there were two control groups: symptomatic controls (N = 131) and healthy controls (N = 27). Mucosal biopsies were collected during ileocolonoscopy and gene expression in inflamed and non-inflamed mucosa was explored. Gene expression profiling was performed using Agilent G3 Human Gene Expression 860K v3 One-Color microarray. We recorded information about treatment escalation to anti-TNF agents or surgery, and anti-TNF response, to explore predictive opportunities of the mucosal transcriptome.Results: Gene expression profiles in symptomatic controls in whom IBD had been excluded resembled that of IBD patients and diverged from that of healthy controls. In non-inflamed Crohn's disease and ulcerative colitis, gene set enrichment analysis revealed dysregulation of pathways involved in basic cellular biological processes. Mitochondria-associated pathways were dysregulated both in non-inflamed and inflamed Crohn's disease and ulcerative colitis (>2.6 normalized enrichment scores <-1.8). Gene expression signatures of Crohn's disease and ulcerative colitis did not predict time for treatment escalation (p = 0.175). No significant association was found between gene expression signatures and anti-TNF response.Conclusion: Non-inflamed samples are probably superior to inflamed samples when exploring gene expression signatures in IBD and might reveal underlying mechanisms central for disease initiation. The gene expression signatures of the control groups were related to if they were symptomatic or not, which may have important implications for future study designs.
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