Shellfish Allergy: a Comprehensive Review

Abstract

Shellfish allergy is of increasing concern, as its prevalence has risen in recent years. Many advances have been made in allergen characterization. B cell epitopes in the major allergen tropomyosin have been characterized. In addition to tropomyosin, arginine kinase, sarcoplasmic calcium-binding protein, and myosin light chain have recently been reported in shellfish. All are proteins that play a role in muscular contraction. Additional allergens such as hemocyanin have also been described. The effect of processing methods on these allergens has been studied, revealing thermal stability and resistance to peptic digestion in some cases. Modifications after Maillard reactions have also been addressed, although in some cases with conflicting results. In recent years, new hypoallergenic molecules have been developed, which constitute a new therapeutic approach to allergic disorders. A recombinant hypoallergenic tropomyosin has been developed, which opens a new avenue in the treatment of shellfish allergy. Cross-reactivity with species that are not closely related is common in shellfish-allergic patients, as many of shellfish allergens are widely distributed panallergens in invertebrates. Cross-reactivity with house dust mites is well known, but other species can also be involved in this phenomenon.

Mite-Induced Asthma and IgE Levels to Shrimp, Mite, Tropomyosin, Arginine Kinase, and Der p 10 Are the Most Relevant Risk Factors for Challenge-Proven Shrimp Allergy

“…Shrimp is considered one of the “big 8” food allergens in children [1], and represents one of the most common causes of allergic reactions to foods in this age group [2]. As reported in a recent meta-analysis [3], the prevalence of self-reported shellfish allergy in Europe is 1.3%, while that of shrimp challenge positivity is about 0.1%, and is more common in older patients.…”

Heterogeneity in Allergy to Mollusks: A Clinical-Immunological Study in a Population From the North of Spain

“…The presence of different epitopes in each of these groups, and in each mollusk in particular, could be the cause of the variability we observed. The sequence homology of tropomyosin in crustaceans is high, 98%, as it is between mollusks, 68% to 88%, while between crustaceans and mollusks it ranges from 56% to 68% [6,8]. We found no differences when we compared the immunoblotting patterns of patients who were allergic only to mollusks with those of patients who were allergic to mollusks and crustaceans.…”

“…The homology in the protein sequence of tropomyosin in crustaceans is high (98%), as is that between mollusks (68%-88%). Between crustaceans and mollusks, homology ranges from 56% to 68% [6][7][8].…”

Recent Advances in Experimental Allergy

“…Allergy to shellfish in one of the leading causes of death by anaphylaxis in humans [64]. Leung et al [65] investigated the use of allergen-specific immunotherapy in the context of shrimp allergy in a mouse model.…”