Project description:Gut microbiome research is rapidly moving towards the functional characterization of the microbiota by means of shotgun meta-omics. Here, we selected a cohort of healthy subjects from an indigenous and monitored Sardinian population to analyze their gut microbiota using both shotgun metagenomics and shotgun metaproteomics. We found a considerable divergence between genetic potential and functional activity of the human healthy gut microbiota, in spite of a quite comparable taxonomic structure revealed by the two approaches. Investigation of inter-individual variability of taxonomic features revealed Bacteroides and Akkermansia as remarkably conserved and variable in abundance within the population, respectively. Firmicutes-driven butyrogenesis (mainly due to Faecalibacterium spp.) was shown to be the functional activity with the higher expression rate and the lower inter-individual variability in the study cohort, highlighting the key importance of the biosynthesis of this microbial by-product for the gut homeostasis. The taxon-specific contribution to functional activities and metabolic tasks was also examined, giving insights into the peculiar role of several gut microbiota members in carbohydrate metabolism (including polysaccharide degradation, glycan transport, glycolysis and short-chain fatty acid production). In conclusion, our results provide useful indications regarding the main functions actively exerted by the gut microbiota members of a healthy human cohort, and support metaproteomics as a valuable approach to investigate the functional role of the gut microbiota in health and disease.
Project description:Cytomegalovirus (CMV) is a prevalent β-herpesvirus that persists asymptomatically in immunocompetent hosts. In people with HIV-1 (PWH), CMV is associated with HIV-1 persistence and particular inflammatory-related co-morbidities. The true causative role of CMV in HIV-associated pathologies however remains unclear given that nearly all PWH are coinfected with CMV. In this study, we examined acute phase immune and virological dynamics in cohorts of SIV-infected rhesus macaques (RMs) that were naturally seropositive or -negative for rhesus CMV (RhCMV). We observed prior to SIV, RhCMV expanded a polyclonal population of target CCR5+CD4+ T cells in gut and lymph nodes (LN) that expressed the chemotactic receptor CXCR3 and were largely not specific for RhCMV. Upon SIV infection, RhCMV+ RMs exhibited higher peak viremia and elevated levels of SIV DNA in the upper and lower intestine. Greater seeding of SIV DNA was associated with a maintenance of CCR5-expressing CD4+ T cells that were enriched within the RhCMV+ gut along a CXCR3-CXCL9 chemotactic axis. Overall, the data suggest that RhCMV can promote SIV susceptibility within a diverse, polyclonal pool of CD4 T cells that are not entirely RhCMV-specific.
Project description:Interventions: Patients with the detection of either cytomegalic cells or IHC-CMV cells were diagnosed with CMV colitis.,Patients older than 18 years with clinical suspicion of CMV colitis but negative biopsy for CMV.,Asymptomatic patients underwent colonoscopy for screening.;Diagnostic,Diagnostic,Diagnostic;CMV colitis,Non-CMV colitis ,Healthy volunteers
Primary outcome(s): Diagnostic performance After colonoscopy Sensitivity, Specificity