Detection of cephalopod allergen in food products by ELISA

Abstract

Mollusks including cephalopods are one significant cause for food allergy due to their major allergen, tropomyosin. To determine cephalopods in food products, we developed a sandwich enzyme-linked immunosorbent assay (ELISA) using a cephalopod tropomyosin-specific monoclonal antibody which was obtained using Japanese flying squid Todarodes pacificus tropomyosin as an immunogen. Our ELISA showed 96.4% reactivity (based on the reactivity to T. pacificus tropomyosin) to tropomyosin from octopus, but no substantial reactivity (< 0.1%) to those from other mollusks (shellfish) and crustaceans. No positive ELISA results were obtained for any cephalopod-free foods. The repeatability coefficients of variation were < 10% and the detection limit based on cephalopod standard protein was 0.24 ppm, sensitivity that meets the requirements of the current food labeling system in Japan. These results showed that the sandwich ELISA is highly specific to cephalopod tropomyosins, and may be useful as a detection method for cephalopods in food products.