Pulsed Ultraviolet Light Reduces Immunoglobulin E Binding to Atlantic White Shrimp (Litopenaeus setiferus) Extract

Susan Percival,Sandra Shriver,Wade Yang,Si-Yin Chung

doi:10.3390/ijerph8072569

Abstract

Pulsed ultraviolet light (PUV), a novel food processing and preservation technology, has been shown to reduce allergen levels in peanut and soybean samples. In this study, the efficacy of using PUV to reduce the reactivity of the major shrimp allergen, tropomyosin (36-kDa), and to attenuate immunoglobulin E (IgE) binding to shrimp extract was examined. Atlantic white shrimp (Litopenaeus setiferus) extract was treated with PUV (3 pulses/s, 10 cm from light source) for 4 min. Tropomyosin was compared in the untreated, boiled, PUV-treated and [boiled+PUV]-treated samples, and changes in the tropomyosin levels were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). IgE binding of the treated extract was analyzed via immunoblot and enzyme-linked immunosorbent assay (ELISA) using pooled human plasma containing IgE antibodies against shrimp allergens. Results showed that levels of tropomyosin and IgE binding were reduced following PUV treatment. However, boiling increased IgE binding, while PUV treatment could offset the increased allergen reactivity caused by boiling. In conclusion, PUV treatment reduced the reactivity of the major shrimp allergen, tropomyosin, and decreased the IgE binding capacity of the shrimp extract.

Highlights

In the United States, approximately 6% of children and 3.7% of adults are affected by one or more food allergies
Our objective was to examine the efficacy of Pulsed ultraviolet light (PUV) exposure on the inactivation of major shrimp allergen by measuring changes in tropomyosin level and immunoglobulin E (IgE) binding
PUV treatment led to a reduction in both tropomyosin level and IgE binding

Summary

Introduction

In the United States, approximately 6% of children and 3.7% of adults are affected by one or more food allergies. Eight major food sources, including cow’s milk, shellfish, egg, fish, tree nuts, peanuts, soybean, and wheat, account for approximately 85% of all food allergies [1]. Allergies to shellfish, such as shrimp, affect 0.1% of American children and 2% of American adults, making shellfish allergies the most common type of food allergy in adults [2]. Tropomyosin plays an important role in muscular contraction, as well as in the regulation of cellular structure and motility [6] Present in both vertebrates and invertebrates, tropomyosin is known to elicit an allergic reaction only when it is derived from invertebrate sources, such as crustaceans, arachnids, insects and mollusks [5]. Two additional shrimp allergens have been identified: myosin light chain (20-kDa) [7] and arginine kinase (40-kDa) [8,9,10]

Objectives

Results

Conclusion