Emerging molecular and environmental biomarkers of shrimp allergy in African Americans in the US.

Abstract

Shrimp allergy (SA), a major cause of food-induced anaphylaxis, represents a disproportionate and under-characterized burden among African American (AA) populations in the United States. Unlike many childhood food allergies, SA is often persistent and commonly presents in adolescence or adulthood, suggesting a role for cumulative environmental exposures in disrupting oral tolerance. A key diagnostic challenge in AA communities is the high prevalence of IgE sensitization to shrimp tropomyosin (Pen a 1), which shares strong structural homology with cockroach and house dust mite tropomyosins, leading to frequent cross-reactive but clinically irrelevant sensitization in urban settings. This review critically examines molecular and environmental biomarkers of SA with a focus on AA populations. We assess the limitations of extract-based IgE testing and component-resolved diagnostics, highlighting how single-component assays may overestimate true clinical allergy. We emphasize the added value of functional assays, particularly the basophil activation test, in distinguishing sensitization from challenge-confirmed allergies. Mechanistically, we discuss how chronic exposure to indoor arthropod allergens, air pollution, and socioenvironmental stressors may drive epithelial barrier dysfunction, IL-33 release, and amplification of type 2 immune pathways, lowering reaction thresholds and influencing disease persistence. We identify key gaps, including limited oral food challenge-confirmed data and underrepresentation of AA cohorts. Finally, we propose equity-centered, integrative research frameworks combining molecular diagnostics, functional assays, environmental assessment, and multi-omics to improve diagnostic precision and advance clinical equity in SA care.