The 6th International Dietary Fibre Conference took place in Paris from 1-3 June 2015. Sensus presented a poster with the title “The interaction of dietary fibres with the immune system as measured in vitro: the example of inulin” by D. Meyer, L. Vogt and P. de Vos.
The interaction of inulin with the immune system can take place at different levels and so far most attention has been given to the consequences of the changes in microbiota and its activity due to inulin consumption. Fermentation products, like short chain fatty acids, may interact with G protein coupled receptors which affects the production of cytokines, bifidobacteria may produce bacteriocins and other products inhibiting growth of potential pathogens, all leading to an improved performance of the immune system. This may for instance lead to a lowered risk for travellers’ diarrhoea with oligofructose consumption. Direct interaction of inulin with the immune system has been suggested, but so far data are limited. This prompted us to carry out in vitro studies with human peripheral mononuclear cells to gain more insight in these potential direct effects. These studies showed that such direct interaction can take place, which receptors are involved, what the consequences are for the production of important pro-inflammatory and anti-inflammatory cytokines and moreover, how the chain length of the inulins influences these effects. With another in vitro system we could show that the barrier function of human intestinal cells can be protected by the activation of the same receptors by inulin.
These data suggest that also direct interaction of inulin with the human immune system could lead to immune modulation with potentially beneficial effects for the host. Final evidence for this requires additional trials with human volunteers.