Two Classes of Allergens, Parvalbumins and Higher Molecular Weight Substances, in Japanese Eel and Bigeye Tuna

Abstract

When assessed by ELISA using sera from five fish-sensitive subjects (1-5), the allergenicity of nine species of fish was found to vary not only among fish species but also among individual patients. In gel filtration on Sephadex G-75 of the crude extracts from Japanese eel and bigeye tuna, allergens were recognized in two fractions, i.e., Fr. I, near the void volume and Fr. II, in the later fractions. Subject 3 and 4 sera reacted to Fr. I, subject 1 and 2 sera reacted to Fr. II, and subject 5 serum reacted both Frs. I and II. The four allergens (Angj 1.01 and 1.02 from Japanese eel and Thu o 1.01 and 1.02 from bigeye tuna) for subjects 1 and 2 were isolated from Fr. II by reverse-phase HPLC on TSKgel ODS-120T. They were all identified as parvalbumins, based on their molecular weights, amino acid compositions, and positive reactions with a monoclonal anti-carp parvalbumin antibody. In conclusion, the major allergens in Japanese eel and bigeye tuna are parvalbumins and/or higher molecular weight substances, depending on patients.