Cloning, expression and characterization of four soy allergens that cross react with bovine caseins

CURCIARELLO, RENATA; CANDREVA ANGELA MARÍA; SMALDINI, PAOLA; GONZÁLEZ, VIRGINIA; BRUNO BLANCH LUIS; PARISI, GUSTAVO; FOSSATI, C. ALBERTO; PETRUCCELLI SILVANA; DOCENA GUILLERMO H.

Viña del Mar, CHILE

Congreso; 9th Latin American Congress of Immunology; 2009

Asociación Latinoamericana de Inmunología, Sociedad Chilena de Inmunología, IUIS

Cow’s milk (CM) allergy is the main food allergy worldwide. Soy-based formulas are widely used as dairy substitute for treatment. However, soy intolerance is frequently observed. We hypothesize that this side effect is due to cross reactive allergens. Our objective was to obtain four recombinant soy allergens that were previously characterized as cross-reactive components. We expressed in E. coli A5A4B3, Gly m α-conglycinin, Gly m Bd 30K/p34 and Gly m Bd 28K/p28) that were immunochemically recognized by ELISA and EAST using CM-specific polyclonal antisera, monoclonal antibodies and IgE-containing sera from CM allergic patients. We in vivo tested this cross-reactivity in a murine model of CM food allergy (clinical signs after oral challenge, cutaneous tests, splenocyte proliferation, etc). Based on bioinformatics data we further expressed a potential peptide that contains the immunodominat cross-reactive epitopes, which also resulted reactive with several CM-specific antibodies. In conclusion, we obtained four recombinant soy allergens, and detected three possible epitopes that may be responsible for the cross-reactivity observed. These results will be relevant in an attempt to reduce the allergenicity of soy components, and may constitute the basis for a potential therapy for tolerance induction.