Recognition of an extensive range of IgE-reactive proteins in cod extract

Allergy to fish is one of the most common food allergies. Gad c 1 is the only fish allergen which has been purified and characterized. Other allergens have been detected by Western blot in cod extracts. We have now improved the Western-blot procedure in order to characterize fish IgE-reactive proteins from extracts prepared under different conditions: pre-rigor mortis and post rigor mortis. EDTA addition or not. and DEAE ion-exchange chromatography. Several IgE-reactive protein bands have been identified over a wide molecular-weight range. In particular, the 104- and 130-kDa IgE-reactive protein bands were detected, These new bands may correspond to aggregates, as EDTA increased the relative amount of the 60-, 67-, 104-, and 130-kDa IgE-reactive protein bands in Western blot, All these bands were also detected by an antiparvalbumin monoclonal antibody. specific to the first calcium-binding site, The longer period of storage increased the relative amounts of the 41-, 80-, 104-, and 130-kDa IgE-reactive protein bands, The 18-kDa band was detected only in fish stored for several days, In conclusion, we have described IgE-reactive protein bands over a wide molecular-weight range (12-130 kDa) in Western blot of cod extract, and shown that EDTA and storage conditions may influence the relative distribution of IgE-reactive protein bands.