A bioengineered version of a common bacteria used in cheese production could be a key to stopping food allergies from developing.

European researchers have reported in the Journal of Allergy and Clinical Immunology that mice pre-treated with genetically modified Lactococcus lactis bacteria and then deliberately sensitised to cow's milk had a significantly smaller allergic reaction after an oral food challenge.

The Lactococcus lactis bacteria had been "transfected" so they would secrete an anti-inflammatory cytokine, interleukin-10 (IL-10).

Researchers Christophe Frossard and Philippe Eigenmann, from the University Hospital of Geneva in Switzerland, and Lothar Steidler, from the University of Cork in Ireland, reported that the Lactococcus lactis strain had "significantly" reduced anaphylaxis in the mice as well as suppressing production of the antigen-specific immunoglobins IgE (the trigger for powerful immune reactions) and IgG.

As well, the bacteria increased production in the gut of the protective immunoglobin IgA.

"These findings open interesting potential options in human beings for the prevention of allergies elicited through sensitization in the gut," they wrote.

"These results suggest that a mico-organism bioengineered to deliver IL-10 in the gut can decrease food-induced anaphylaxis and provide and option to prevent IgE-type sensitization to common food allergens."