P774 Metagenomics and metabolomics of patients with inflammatory bowel disease and their unaffected relatives
Vancamelbeke M.*1, Sabino J.1, Deroover L.1, Vandermeulen G.1, Luypaerts A.1, Ferrante M.1,2, Falony G.3, Vieira-Silva S.3, Verbeke K.1, Raes J.3, Cleynen I.4, Vermeire S.1,2
1KU Leuven, Department of Clinical and Experimental Medicine, Translational Research Center for Gastrointestinal Disorders, Leuven, Belgium 2University Hospitals Leuven, Department of Gastroenterology and Hepatology, Leuven, Belgium 3Rega Institute for Medical Research, VIB, KU Leuven, Department of Microbiology and Immunology, Laboratory of Molecular Bacteriology, Leuven, Belgium 4KU Leuven, Department of Human Genetics, Laboratory for Complex Genetics, Leuven, Belgium
Dysbiosis, intestinal barrier dysfunction and metabolic alterations of the gut microbiota have been implicated in the pathogenesis of inflammatory bowel disease. We studied the faecal microbiome and metabolome, as well as intestinal permeability of multiple-affected families with Crohn's disease (CD) or ulcerative colitis (UC) to investigate which factors are associated with disease.
Faecal and urine samples were obtained from 84 individuals of 19 families (37 CD, 11 UC and 36 unaffected first-degree relatives (FDR)). Faecal microbial profiling was done using 16S rDNA paired-end sequencing (Illumina MiSeq). Sequencing depth was downsized to 10,000 reads/sample. Taxonomic annotation was performed with the RDP classifier. Faecal volatile organic metabolites were measured using GC-MS. Metabolite data were relatively quantified to an internal standard, and subject-specific compounds were discarded. Metabolite profiles were clustered by PLS-DA (Unscrambler). Small intestinal permeability (IP) was measured using a 2-hour lactulose-mannitol urine test. Statistical analyses were conducted in R with multiple testing correction (Benjamini-Hochberg).
Microbial richness and composition were significantly different in patients with CD compared to UC and FDR (p<0.05), whereas these comparisons were not significant for UC versus FDR. Vector fitting confirmed diagnosis as the main driver of the variability in microbial composition (p<0.001), followed by family ID (p=0.02). The genera discriminating CD and FDR included 16 known and new genera, such as
Significantly different metagenomic and metabolomic profiles were observed between CD patients and healthy individuals with a shared familial background.
- Posted in: Poster presentations: Microbiology (2017)