HELIUS cohort
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ABSTRACT:
PROVIDER: EGAS00001002969 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Environmental influences such as infections and dietary changes strongly affect a host’s microbiota. In the steady state, however, host genetics may influence the microbiota composition, as suggested by the greater similarity between the microbiomes of identical twin pairs compared to non-identical twins. Understanding the role of polymorphic mechanisms in regulating the commensal communities is complicated by the variability of human genomes and microbiomes, and by microbial sensitivity to the environment. Animal studies allow genetic modifications, but are also sensitive to influences known as ‘cage’ or ‘legacy’ effects. Here, we analyzed ex-germ-free mice of various genetic backgrounds, including immunodeficient and Major Histocompatibility Complex (MHC)-congenic strains repopulated with identical input microbiota. We found that the host’s genetic polymorphic mechanisms did indeed affect the gut microbiome and that both innate (e.g. anti-microbial peptides, complement, pentraxins and enzymes affecting microbial survival), as well as adaptive (both MHC-dependent and MHC-independent) pathways influenced the microbiota. These polymorphic mechanisms regulated only a limited number of microbial lineages (independently of their abundance). In addition, our comparative analyses suggested that some microbes might benefit from the specific immune responses that they elicit.
2019-08-29 | GSE136572 | GEO
Project description:The gut microbiota plays an important role in host health. Microbiota dysbiosis has been implicated in the global epidemic of Metabolic Syndrome (MetS) and could impair host metabolism by noxious metabolites. It has been well established that the gut microbiota is shaped by host immune factors. However, the effect of T cells on the gut microbiota is yet unknown. Here, we performed a metagenomic whole-genome shotgun sequencing (mWGS) study of the microbiota of TCRb-/- mice, which lack alpha/beta T cells.
2024-05-06 | GSE262397 | GEO
Project description:Non-alcoholic fatty liver disease (NAFLD) is a sexually dimorphic disease influenced by dietary factors. Here, we assess the metabolic and hepatic effects of dietary amino acid (AA) source in Western diet (WD)-induced NAFLD in male and female mice. The AA source was either casein or a free AA mixture mimicking the composition of casein. As expected, males fed a casein-based WD displayed glucose intolerance, fasting hyperglycemia, and insulin-resistance and developed NAFLD associated with changes in hepatic gene expression and dysbiosis. In contrast, males fed the AA-based WD showed no steatosis, a similar gene expression profile as males fed a control diet, and a distinct microbiota composition compared to males fed a casein-based WD. Females were protected against WD-induced liver damage, hepatic gene expression, and gut microbiota changes regardless of the AA source. Thus, free dietary AA intake prevents the unhealthy metabolic outcomes of a WD in a sex-specific manner.
2024-01-01 | GSE234591 | GEO
Project description:Gut Microbiota Composition in Patients Living with HIV
| PRJNA762595 | ENA
Project description:This study shows that the consumption of cheese modulates the diversity of the oral microbiota. The persistence of exogenous bacteria in the oral cavity appears to be linked to thesalivary proteome composition, which are influenced by oxidative stress. The origin of this oxidative stress has not been determined.
2024-10-17 | PXD041306 | Pride
Project description:Host Defense Peptides (HDPs) such as cathelicidins are multifunctional effectors of the innate immune system with both antimicrobial and pleiotropic immunomodulatory functions. Chicken cathelicidin-2 (CATH-2) has multiple immunomodulatory effects in vitro and the D-amino acid analog of this peptide has been shown to partially protect young chicks from a bacterial infection. However, the mechanisms responsible for CATH-2 mediated in vivo protection have not been investigated so far. In this study, D-CATH-2 was administered in ovo and the immune status and microbiota of the chicks were investigated at 7 days posthatch to elucidate the in vivo mechanisms of the peptide. In three consecutive studies, no effects on numbers and functions of immune cells were found and only small changes were seen in gene expression of PBMCs. Between studies, intestinal microbiota composition was highly variable, suggesting that it was strongly influenced by environmental factors. In both studies, in ovo D-CATH-2 treatment caused significant reduction of Ruminococcaceae and Butyricicoccus in the cecum and Escherichia/Shigella in both ileum and cecum. In conclusion, this study shows that, in the absence of an infectious stimulus, in ovo administration of a CATH-2 analog alters the microbiota composition, but does not affect the chicks immune system posthatch.
2018-04-01 | GSE97771 | GEO
Project description:The gut microbiota is closely associated with digestion, metabolism, immunity, and host health. The imbalance of the microbial community in livestock directly affects their well-being and, consequently, productivity. The composition and diversity of the gut microbiota are influenced not only by host genetics but also by environmental factors such as the microbial complexity of the rearing environment, feeds, and antibiotics. Here, we focus on the comparison of gut microbial communities in miniature pigs developed for xenotransplantation in specific pathogen-free (SPF) and conventional (non-SPF) facilities. To identify the disparities in gut microbial composition and functionality between these two environments, 16S RNA metagenome sequencing was conducted using fecal samples. The results revealed that the non-SPF pigs had higher gut microbiota diversity than the SPF pigs. The genera Streptococcus and Ruminococcus were more abundant in SPF pigs than in non-SPF pigs. Blautia, Bacteroides, and Roseburia were exclusively observed in SPF pigs, whereas Prevotella was exclusively found in non-SPF pigs. Carbohydrate and nucleotide metabolism, as well as environmental information processing, were predicted to be enriched in SPF pigs. In addition, energy and lipid metabolism, along with processes related to genetic information, cellular communication, and diseases, were predicted to be enriched in non-SPF pigs. This study makes an important contribution to elucidating the impact of environments harboring a variety of microorganisms, including pathogens, on the gut microbiota of miniature pigs. Furthermore, we sought to provide foundational data on the characteristics of the gut microbiota in genetically modified pigs, which serve as source animals for xenotransplantation.
2024-04-22 | GSE264183 | GEO
Project description:Rationale: Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections and hospitalizations in infants worldwide. Known risk factors, however, incompletely explain the variability of RSV disease severity among children. We postulate that severity of RSV infection is influenced in part by modulation of the host immune response by the local microbial ecosystem at the time of infection. Objectives: To define whether different nasopharyngeal microbiota profiles are associated with distinct host transcriptome profiles and severity in children with RSV infection. Methods: We analyzed the nasopharyngeal microbiota profiles of young children with mild and severe RSV disease and healthy matched controls by 16S-rRNA sequencing. In parallel, we analyzed whole blood gene expression profiles to study the relationship between microbial community composition, the RSV-induced host transcriptional response and clinical disease severity. Measurements and Main results: We identified five nasopharyngeal microbiota profiles characterized by enrichment of H. influenzae, Streptococcus, Corynebacterium, Moraxella or S. aureus. RSV infection and RSV hospitalization were positively associated with H. influenzae and Streptococcus, and negatively associated with S. aureus abundance, independent of age. The host response to RSV was defined by overexpression of interferon-related genes, and this was independent of the microbiota composition. On the other hand, transcriptome profiles of RSV infected children with H. influenzae and Streptococcus-dominated microbiota were characterized by greater overexpression of genes linked to toll-like receptor-signaling and neutrophil activation and were more frequently hospitalized Conclusions: Our data suggest an immunomodulatory role for the resident nasopharyngeal microbial community early in RSV infection, potentially affecting RSV disease severity.
2016-05-09 | GSE77087 | GEO
Project description:A mucus layer covers and protects the intestinal epithelial cells from direct contact with microbes. This mucus layer not only prevents inflammation but also plays an essential role in microbiota colonization, indicating the complex interplay between mucus composition-microbiota and intestinal health. However, it is unknown whether the mucus layer is influenced by age or sex and whether this contributes to reported differences in intestinal diseases in males and females or with ageing. Therefore, in this study we investigated the effect of age on mucus thickness, intestinal microbiota composition and immune composition in relation to sex. The ageing induced shrinkage of the colonic mucus layer was associated with bacterial penetration and direct contact of bacteria with the epithelium in both sexes. Additionally, several genes involved in the biosynthesis of mucus were downregulated in old mice, especially in males, and this was accompanied by a decrease in abundances of various Lactobacillus species and unclassified Clostridiales type IV and XIV and increase in abundance of the potential pathobiont Bacteroides vulgatus. The changes in mucus and microbiota in old mice were associated with enhanced activation of the immune system as illustrated by a higher percentage of effector T cells in old mice. Our data contribute to a better understanding of the interplay between mucus-microbiota-and immune responses and ultimately may lead to more tailored design of strategies to modulate mucus production in targeted groups.
2017-08-28 | GSE94515 | GEO