Prebiotic oligosaccharides enhance immuno-regulatory capacities of probiotic bacteria-proof of concept of synbiotic approach

The combination of probiotic bacteria with prebiotics (synbiotics) is considered to selectively manipulate the composition of the microbiota in direction to health benefits of the host which is of special interest in the view of the growing application of synbiotics in treatment of diseases and food. Aim of the study was to investigate the impact of different bacterial strains in combination with prebiotic oligosaccharides on the cytokine release of human monocyte-derived dendritic cells (MoDC). Immature MoDC prepared from peripheral blood of healthy non-atopic volunteers were stimulated with a Lactobacillus and Bifidobacterium strain (107-105cfu) in the presence of different combinations of prebiotic GOS (galacto oligosaccharides), FOS (fructose oligosaccharides) and AOS (pectin derived acidic oligosaccharides). IL-12 p70 and IL-10 were analyzed after 24h in the supernatants. Incubation of MoDC with different concentrations of the Lactobacillus and Bifidobacterium strain in combination with prebiotic oligosaccharides revealed that GOS/FOS (9:1) and GOS/ FOS/AOS (9:1:2) had a significant additive effect on bacteriainduced IL-10 secretion of human MoDC, the ability of these prebiotic oligosaccharides to increase IL-12p70 production was less pronounced. Cytokine-enhancement of bacteria-treated human MoDC by GOS/FOS and GOS/FOS/AOS suggests immunoregulatory capacities in vitro. Thus, the tested Bifidobacterium and Lactobacillus strains in combination with prebiotic oligosaccharides might be considered as health promoting synbiotics providing new strategies for the therapeutical treatment of diseases including skin diseases, allergy or infection and open new aspects for the application in food.