Humoral immune response in mice immunised by oral and subcutaneous routes with Isosoy proteins

This study compares the allergenic potential of Isosoy®, a soy germen commercialised as isoflavone for dietary supplements, with crude soy extract (CSE) and purified isoflavone. Specific antibodies (IgG, IgE and IgG1) generated in Swiss mice by oral and subcutaneous route with Isosoy® also recognised proteins of crude soy extract, but no reaction against purified isoflavone, like clearly demonstrated by ELISA, Western blot and immunoprecipitation assay. These results are in agreement with the same protein profile between Isosoy® and CSE observed by polyacrylamide gel electrophoresis (SDS-PAGE). The immunoprecipitation assay demonstrates that Isosoy® boiling cannot inactivate the interaction with specific antibodies generated by oral route with unboiled Isosoy®. Results suggest that Isosoy® could lead to allergic reactions even after heat treatment.