Seafood is an important component in human diet and nutrition worldwide. However, seafood also constitutes one of the most important groups of foods in the induction of immediate (type I) food hypersensitivity, which significantly impacts the quality of life and healthcare cost. Extensive efforts within the past two decades have revealed the molecular identities and immunological properties of the major fish and shellfish allergens. The major allergen involved in allergy and cross-reactivity among different fish species was identified as parvalbumin while that responsible for shellfish (crustaceans and mollusks) allergy was identified as tropomyosin. The cloning and expression of the recombinant forms of these seafood allergens facilitate the investigation on the detailed mechanisms leading to seafood allergies, mapping of IgE-binding epitopes, and assessment of their allergenicity and stability. Future research focusing on the immunological cross-reactivity and discovery of novel allergens will greatly facilitate the management of seafood allergies and the design of effective and life-long allergen-specific immunotherapies.

T cell epitope-based oral immunotherapy is effective in reducing allergic responses towards shrimp tropomyosin. This is a novel strategy for clinical management of shellfish allergy and is a model for mechanistic studies of oral immunotherapy.

Shellfish allergy caused by undesirable immunological responses upon ingestion of crustaceans and mollusks is a common cause of food allergy, especially in the Asia-Pacific region. While the prevalence of shellfish allergy is increasing, the mainstay of clinical diagnosis for these patients includes extract-based skin prick test and specific IgE measurement while clinical management consists of food avoidance and as-needed use of adrenaline autoinjector should they develop severe allergic reactions. Such a standard of care is unsatisfactory to both patients and healthcare practitioners. There is a pressing need to introduce more specific diagnostic methods, as well as effective and safe therapies for patients with shellfish allergy. Knowledge gained on the identifications and defining the immuno-molecular features of different shellfish allergens over the past two decades have gradually translated into the design of new diagnostic and treatment options for shellfish allergy. In this review, we will discuss the epidemiology, the molecular identification of shellfish allergens, recent progress in various diagnostic methods, as well as current development in immunotherapeutic approaches including the use of unmodified allergens, hypoallergens, immunoregulatory peptides and DNA vaccines for the prevention and treatment of shellfish allergy. The prospect of a “cure “for shellfish allergy is within reach.

Seafood allergy is a hypersensitive disorder with increasing prevalence worldwide. Effective and accurate diagnostic workup for seafood allergy is essential for clinicians and patients. Parvalbumin and tropomyosin are the most common fish and shellfish allergens, respectively. The diagnosis of seafood allergies is complicated by cross-reactivity among fish allergens and between shellfish allergens and other arthropods. Current clinical diagnosis of seafood allergy is a complex algorithm that includes clinical assessment, skin prick test, specific IgE measurement, and oral food challenges. Emerging diagnostic strategies, such as component-resolved diagnosis (CRD), which uses single allergenic components for assessment of epitope specific IgE, can provide critical information in predicting individualized sensitization patterns and risk of severe allergic reactions. Further understanding of the molecular identities and characteristics of seafood allergens can advance the development of CRD and lead to more precise diagnosis and improved clinical management of seafood allergies.