On the other hand, gut microbiota signalling through TLR-5 and MyD88 dependent pathways regulates IgG and IgE levels against bacterial and non-bacterial antigens in mice64–66, also signalling through various pattern recognition receptor such as TLR-2 and TLR-4 has been associated with IgE mediated eccema67 and food allergy in humans68, suggesting that microbiota produced metabolites or specific structural components could stimulate innate immunity and influence systemic antibody levels. This evidence concerns the gene TLR5 and food allergy.