A novel synbiotic concept derived from cow's milk-free source materials reduced allergic symptoms in preventive and therapeutic models for hen's egg allergy

Background: For applications in severe cow's milk allergic (CMA) infants, a new synbiotic concept was designed from source materials and probiotic bacteria that were cultured completely cow's milkfree. The preventive and therapeutic effects of this concept were tested in models for hen's egg allergy. Methods: Mice were orally sensitised once a week for 5 weeks to ovalbumin (OVA) using cholera toxin as an adjuvant. Non-sensitised mice received cholera toxin in PBS only. Mice were either fed the synbiotic concept (short-chain fructo-, long-chain fructo-and acidic oligosaccharides plus Bifidobacterium breve M-16V) continuously from day-14 or for 3 weeks starting after the last sensitisation. Anaphylactic shock reactions, a drop in body temperature and acute allergic skin responses were measured as clinically-related allergic symptoms upon challenge to OVA. Allergen-specific IgE and mMCP-1, as a reflection of intestinal mast cell degranulation were measured in serum. TGF-beta and IL-10 were determined in ileum using PCR. Results: Anaphylactic shock symptoms, a drop in body temperature, an acute allergic skin response, enhanced levels of mMCP-1 and specific OVA-IgE were observed in sensitised mice. Interestingly, the synbiotic concept reduced anaphylactic shock symptoms, the changes in body temperature and the acute allergic skin response in both the preventive and therapeutic settings. In the therapeutic setting mMCP-1 was also reduced. mRNA expression of TGF-beta, but not of IL-10, was enhanced in the preventive setting. Conclusion: A new synbiotic concept, suitable for the dietary management of severe CMA, shows relevant immunomodulatory capacity if fed to both naïve and already sensitised mice, suggesting potential benefits on allergy-related parameters in humans. Although an increase in local TGF-beta expression was observed, further research is needed to elucidate the mechanisms underlying the observed effects.