Similarly, recent studies on the mechanisms of probiotics highlight their effects on epithelial barrier function via Toll-like

receptor 2 signaling and the generation of regulatory dendritic cells and regulatory CD4+Foxp3+ T cells in peripheral tissues CP-690550 mouse [12, 13]. The latter mechanism is linked to the administration of a collection of five strains which induced a high IL-10/IL-12 ratio in co-culture with immune cells [12]. Administration of these strains was shown to have a therapeutic effect in experimental mouse models of inflammatory bowel disease, atopic dermatitis, and rheumatoid arthritis and was associated with enrichment of CD4(+)Foxp3(+) Tregs in the inflamed regions [12]. The cell products of probiotics that are responsible for modulation of cytokine induction are largely not known but might involve modifications of some of the known Microbe Associated Molecular Patterns (MAMPs) such lipoteichoic acids (LTA) [14–16] and (lipo)proteins selleck chemicals llc localized on the bacterial cell surface [17] which interact with Toll-like receptors. Additionally cell-surface associated bacterial glycosylated proteins or exopolysaccharides [18] may interact with other host pattern recognition receptors including the C-type lectins and scavenger receptors

found on antigen presenting cells [19]. These extracellular and secreted products produced by probiotic cells are the likely targets for strain-dependent interactions with host cells and have been the focus of several recent reviews [6, 20, 21]. Certain strains of Lactobacillus plantarum are marketed as probiotics and reported to confer various health effects including immunomodulation [22]. The genome sequence of L. plantarum strain WCFS1 is known [23] and extensive bioinformatics tools [24, 25], molecular models

[26], and a database of genome hybridization profiles [27, 28] are available for this organism. It is a single colony isolate of strain 5-FU supplier NCIMB8826, which was shown to survive gastrointestinal passage after oral administration to healthy volunteers [29]. Global gene expression profiling of L. plantarum WCFS1 in the intestinal contents of the human gut and conventionally-raised and germ-free mice has shown that this organism adapts for growth in vivo by modification of its cell-surface composition and metabolism in a diet-dependent manner [30–34]. Human duodenal transcriptional response profiles have also been obtained in response to ingestion of L. plantarum WCFS1 [35, 36]. Notably, exponential phase and stationary phase L. plantarum WCFS1 cells elicited distinct human duodenal transcript profiles which appeared to mainly result from differential modulation of canonical NF-κβ-dependent signaling pathways associated with immune tolerance [35].