title: Transcriptomic response of immune signalling pathways in intestinal epithelial cells exposed to lipopolysaccharides, Gram-negative bacteria or potentially probiotic microbes.
abstract: In order to understand the appropriate use of potentially probiotic Gram-positive microbes through their introduction in the gut microbiome, it is necessary to understand the influence of individual bacteria on the host-response system at a cellular level. In the present study, we have shown that lipopolysaccharides, flagellated Gram-negative bacteria, potentially probiotic Gram-positive bacteria and yeast interact differently with human intestinal epithelial cells with a custom-designed expression microarray evaluating 17 specific host-response pathways. Only lipopolysaccharides and flagellated Gram-negative bacteria induced inflammatory response, while a subset of Gram-positive microbes had anti-inflammatory potential. The main outcome from the study was the differential regulation of the central mitogen-activated protein kinase signalling pathway by these Gram-positive microbes versus commensal/pathogenic Gram-negative bacteria. The microarray was efficient to highlight the impact of individual bacteria on the response of intestinal epithelial cells, but quantitative real-time polymerase chain reaction validation demonstrated some underestimation for down-regulated genes by the microarray. This immune array will allow us to better understand the mechanisms underlying microbe-induced host immune responses.
authors.affiliation: Lallemand Human Nutrition, Montreal, QC Canada.
authors.forename: J
authors.initials: J
authors.lastname: Audy
authors.forename: O
authors.initials: O
authors.lastname: Mathieu
authors.forename: J
authors.initials: J
authors.lastname: Belvis
authors.forename: T A
authors.initials: TA
authors.lastname: Tompkins
mesh_terms: D001422:Bacterial Adhesion; D001644:Bifidobacterium / Q000276:immunology; D015536:Down-Regulation; D004847:Epithelial Cells / Q000276:immunology* / Q000382:microbiology; D005786:Gene Expression Regulation; D015894:Genome, Human; D019073:HT29 Cells; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000382:microbiology; D016906:Interleukin-9 / Q000276:immunology; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology* / Q000382:microbiology; D007778:Lactobacillus / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology*; D020935:MAP Kinase Signaling System; D020411:Oligonucleotide Array Sequence Analysis; D019936:Probiotics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012475:Salmonella / Q000276:immunology*; D014158:Transcription, Genetic; D059467:Transcriptome; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: C508607:IL9 protein, human; D016906:Interleukin-9; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha