Study on the regulatory effects and mechanisms of action of bifidobacterial exopolysaccharides on anaphylaxes in mice

Abstract

This study used bifidobacterial exopolysaccharides (EPSs) from the selected strains of Bifidobacterium bifidum WBBI01 and WBIN03, Bifidobacterium breve WBBR04, Bifidobacterium infantis WBAN07 and Bifidobacterium longum WBLO01 to explore the EPSs regulatory effect on anaphylaxis in mice. First of all, allergy mouse models were established via subcutaneous injection followed by OVA gavage, and then the EPSs from the five Bifidobacteria were fed into the mice via continuous gavage. Samples were taken from the mice periodically to determine the changes of cytokine levels in serum, including those of IgE, IgG, IL-4, IL-5, IL-13 and INF-γ. The test revealed that the EPSs from B. breve WBBR04 could considerably relieve food allergy in the mouse models, but the effect of B. infantis WBAN07 was unsatisfactory. Based on the above conclusions, the EPSs of B. bifidum WBBR04 and WBIN03, B. breve WBBR04, and B. longum WBLO01 were respectively incubated with the small intestine tissue sections of an allergic mouse model. The resulting culture supernatants were then tested. Based on the above, it can be concluded that EPS of B. breve WBBR04 can enhance the intestinal barrier integrity by attaching themselves onto the inner walls of the small intestine, hence effectively isolating the allergens and preventing food allergy.

Keywords: Allergy model; Barrier; Bifidobacterial exopolysaccharide.