49I-9

Food allergic reactions are often considered to be IgE-mediated, where cross-linking of food allergen-specific IgE molecules on the surface of mast cells and basophils occurs following ingestion of the food allergen to which the individual is sensitive, causing immediate and late-phase reactions. Soybean is a member of the legume family of plants that includes peanuts. Soybean, together with milk, peanuts and eggs, are the major allergenic foods. A number of soy proteins that bind antibodies, especially IgE, have been identified. To discover soybean allergens associated IgE, we exploited this technology for the identification of soybean allergy associated antigens eliciting antibodies in the autologous host.

The major goal of this study is to define the antigens of soybean allergy that can be used as disease marker for immunotherapeutics and diagnosis.

We performed a serological analysis of cDNA expression library (SEREX) to identify soy proteins associated with sera of patients with atopic dermatitis. A cDNA expression library was constructed from soybean seeds and was screened with sera of 20 patients with atopic dermatitis to soybean ingestion.

Twelve clones were identified after this immunoscreening. These clones are Glycinin G4 (X02626), b-conglycinin b-subunit (S44893), Profilin (AJ223982), Kunitz-trypsin inhibitor (S45092), Gly m Bd 30K (J05560), Enolase, Cytosolic malate dehydrogenase, 3-ketoacyl-CoA thiolase(AY383736) and four unidentified genes. We are currently working the functional characterization of these allergens.

We showed that the IgE antibodies in sera of the patients with atopic dermatitis recognize several proteins through serological analysis of recombinant cDNA expression libraries (SEREX). These proteins were assumed to be possible allergens eliciting IgE-mediated food allergies in the patients.