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- Kalla, Rahul, et al.
(author)
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EPIGENETIC ALTERATIONS IN IBD : DEFINING GEOGRAPHICAL, GENETIC, AND IMMUNEIN-FLAMMATORY INFLUENCES ON THE CIRCULATING METHYLOME
- 2021
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In: Gut. - : BMJ Publishing Group Ltd. - 0017-5749 .- 1468-3288. ; 70:Suppl. 4, s. A5-A5
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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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| 2. |
- Salihovic, Samira, Associate Senior Lecturer, 1985-, et al.
(author)
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Identification and validation of a blood- based diagnostic lipidomic signature of pediatric inflammatory bowel disease
- 2024
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In: Nature Communications. - : NATURE PORTFOLIO. - 2041-1723. ; 15:1
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Journal article (peer-reviewed)abstract
- Improved biomarkers are needed for pediatric inflammatory bowel disease. Here we identify a diagnostic lipidomic signature for pediatric inflammatory bowel disease by analyzing blood samples from a discovery cohort of incident treatment-na & iuml;ve pediatric patients and validating findings in an independent inception cohort. The lipidomic signature comprising of only lactosyl ceramide (d18:1/16:0) and phosphatidylcholine (18:0p/22:6) improves the diagnostic prediction compared with high-sensitivity C-reactive protein. Adding high-sensitivity C-reactive protein to the signature does not improve its performance. In patients providing a stool sample, the diagnostic performance of the lipidomic signature and fecal calprotectin, a marker of gastrointestinal inflammation, does not substantially differ. Upon investigation in a third pediatric cohort, the findings of increased lactosyl ceramide (d18:1/16:0) and decreased phosphatidylcholine (18:0p/22:6) absolute concentrations are confirmed. Translation of the lipidomic signature into a scalable diagnostic blood test for pediatric inflammatory bowel disease has the potential to support clinical decision making. Diagnostic blood-based biomarkers of pediatric IBD are limited. Here, the authors demonstrate a diagnostic lipidomic signature, comprising only of two molecular lipids. Translation of this signature into a scalable test has the potential to support clinical decision making.
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