BACKGROUND: Reduced microbial diversity has been associated with inflammatory bowel disease (IBD) and probiotic bacteria have been proposed for its prevention and/or treatment. Nevertheless, comparative studies of strains of the same subspecies for specific health benefits are scarce. Here we compared two Bifidobacterium longum ssp. longum strains for their capacity to prevent experimental colitis. METHODS: Immunomodulatory properties of nine probiotic bifidobacteria were assessed by stimulation of murine splenocytes. The immune responses to B. longum ssp. longum CCM 7952 (Bl 7952) and CCDM 372 (Bl 372) were further characterized by stimulation of bone marrow-derived dendritic cell, HEK293/TLR2 or HEK293/NOD2 cells. A mouse model of dextran sulphate sodium (DSS)-induced colitis was used to compare their beneficial effects in vivo. RESULTS: The nine bifidobacteria exhibited strain-specific abilities to induce cytokine production. Bl 372 induced higher levels of both pro- and anti-inflammatory cytokines in spleen and dendritic cell cultures compared to Bl 7952. Both strains engaged TLR2 and contain ligands for NOD2. In a mouse model of DSS-induced colitis, Bl 7952, but not Bl 372, reduced clinical symptoms and preserved expression of tight junction proteins. Importantly, Bl 7952 improved intestinal barrier function as demonstrated by reduced FITC-dextran levels in serum. CONCLUSIONS: We have shown that Bl 7952, but not Bl 372, protected mice from the development of experimental colitis. Our data suggest that although some immunomodulatory properties might be widespread among the genus Bifidobacterium, others may be rare and characteristic only for a specific strain. Therefore, careful selection might be crucial in providing beneficial outcome in clinical trials with probiotics in IBD.
- MeSH
- Bifidobacterium klasifikace fyziologie MeSH
- dendritické buňky mikrobiologie patologie MeSH
- HEK293 buňky MeSH
- imunoenzymatické techniky MeSH
- kolitida chemicky indukované prevence a kontrola MeSH
- lidé MeSH
- modely nemocí na zvířatech * MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- probiotika farmakologie MeSH
- signální adaptorový protein Nod2 genetika metabolismus MeSH
- síran dextranu toxicita MeSH
- střeva mikrobiologie patofyziologie MeSH
- toll-like receptor 2 genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
UNLABELLED: An understanding of adherence ability is crucial in many areas, for example, in research on biofilms, evaluation of probiotics or in biotechnology. In all these analyses, the reproducible washing is very important in the prevention of false results. During washing, the force, direction of the flow, position of the pipette tip, number of washing cycles, type of washing solution and the way of removing the washing solution can be sources of inappropriate stress to attached cells. To overcome these problems, we here propose the use of high mass density solutions as flotation agents. As the density of bacteria is lower than that of the flotation solutions, nonattached or weakly attached bacteria are moved to the surface due to hydrostatic force. Caesium chloride, ammonium nitrate and sodium diatrizoate solutions, which are commonly used as FAs, were compared with a standard method of rinsing. Several concentrations of agents were used to investigate the optimal concentration and influence of hydrostatic pressure on adhered micro-organisms. We show that flotation is a rapid method for distinguishing between adhered and weakly attached or loosed cells with reproducible results. Due to its range of possible mass density concentration, the best FA was shown to be caesium chloride. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study that suggests using flotation agents to separate planktonic from adhered bacteria. When a high-density solution is used, buoyancy of bacteria ensures their segregation in the solution. Flotation agents could be used instead of washing procedure, which is inaccurate and hardly reproducible. High-density flotation agents could be used for more precise evaluation of bacterial adherence in many assays, such as research of biofilms or evaluation of probiotics.
Prebiotics are generally considered to promote the function or viability of probiotics via their fermentation, but their effect on the adherence of probiotics is still unclear. In this study, we examined the effect of 4 commercially available prebiotics [Orafti GR, Orafti P95, and Orafti Synergy (Beneo GmbH, Mannheim, Germany), and Vivinal (Friesland Foods Domo, Amersfoort, the Netherlands)] and 3 simple saccharides (glucose, galactose, and lactose) on the adherence of 5 probiotic type strains, 2 lactococci starter cultures, and 5 potential dairy probiotic strains from the Culture Collection of Dairy Microorganisms (Tábor, Czech Republic). Adherence was tested in microtiter plates on the following types of substrate: polystyrene alone and polystyrene coated with either porcine mucus or cocultures of the human colon cell lines Caco2 and HT29-MXT (1:9 ratio of HT29-MXT:Caco2). Adherence was evaluated as a change in fluorescence in the well of a microtiter plate. The most commonly observed effect (with a few exceptions) of prebiotics was decreased adherence of the tested strains observed on all types of substrate. The tested saccharides, which are part of the residual compounds of the used prebiotics, had a very similar effect-eliciting a decrease in adherence ability in the majority of the probiotic strains.
- MeSH
- Bifidobacterium izolace a purifikace MeSH
- Caco-2 buňky MeSH
- Enterococcus izolace a purifikace MeSH
- fermentace MeSH
- Lacticaseibacillus rhamnosus izolace a purifikace MeSH
- Lactobacillus acidophilus izolace a purifikace MeSH
- Lactococcus izolace a purifikace MeSH
- lidé MeSH
- mléčné výrobky mikrobiologie MeSH
- nádorové buněčné linie MeSH
- oligosacharidy aplikace a dávkování MeSH
- potravinářská mikrobiologie MeSH
- prasata MeSH
- prebiotika * MeSH
- probiotika * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Německo MeSH
- Nizozemsko MeSH
