UNDERSTANDING THE HUMAN GUT MICROBIOTA IN INFLAMMATORY BOWEL DISEASES

AGUILERA, PABLO; CEREZO JIMENA; MILANO, CLAUDIA; QUESADA, SOFÍA; SPIAZZI, RENATA; ALBERTO PENAS-STEINHARDT; ROSSO, AYELÉN DAIANA; CIMOLAI, MARÍA CECILIA; CONLON, CAROLINA; BELFORTE, FIORELLA S.

Congreso; LXVII Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica; 2022

BACKGROUND: Inflammatory Bowel Disease (IBD) is the most common form of intestinal inflammation associated with a deregulated immune-system response to commensal microbiota in a genetically susceptible host. IBD includes ulcerative colitis (UC) and Crohn disease (CD). In the present study we aim to describe the unknown gut microbiota of IBD-patients in comparison with healthy individuals of the Argentine population. METHODS: We evaluated 13 non-IBD-controls, 20 UC-patients and 14 CD-patients from Hospital Alejandro Posadas Buenos Aires. Fecal DNA was extracted and hypervariable regions V3-V4 of the bacterial 16SR-gene were sequenced using a MiSeq-Platform and analyzed with the QIIME2 environment. Differential functional pathways were evaluated using PICRUSt. Core microbiota was defined as the set of amplicon sequence variants detected in 50--100% of the samples with a relative abundance threshold value above 0.01% (calculated with Core microbiome from R package). RESULTS: However, differences in alpha diversity were found in CD compared to controls (Shannon q=0.04). The genus Bifidobacterium was found to be overrepresented in UC compared to controls. Our analyzes also Beta diversity was significantly different between groups (UniFrac distances PERMANOVA p-value