Shrimp tropomyosin (Pen a 1) (Pen a 1)

Shrimp tropomyosin, specifically the Pen a 1 isoform, is a highly conserved alpha-helical coiled-coil protein that plays a fundamental role in the muscle contraction of crustaceans. It functions by binding to actin filaments and regulating the access of myosin heads to actin, thereby controlling the contraction-relaxation cycle (UniProt P13907). In clinical immunology, it is identified as the primary and dominant allergen responsible for shellfish allergy, affecting approximately 80% of shrimp-allergic individuals (PMID: 8144283). The protein is notably heat-stable and resistant to pepsin digestion, allowing it to maintain its allergenicity even after cooking and ingestion. Exposure to shrimp tropomyosin in sensitized individuals triggers an IgE-mediated immune response that can lead to severe clinical manifestations, including urticaria, angioedema, and life-threatening anaphylaxis (NIH/NCBI). Furthermore, its high sequence homology with tropomyosins in other invertebrates, such as dust mites and cockroaches, leads to significant cross-reactivity and complicates the management of allergic diseases. While not a traditional drug target, it is the central focus of allergen-specific immunotherapy (AIT) and diagnostic component-resolved diagnostics (CRD) (WHO/IUIS Allergen Nomenclature).

Other names

Met e 1TropomyosinCrustacean tropomyosinPen a 1.0101Major shrimp allergen

Induction of immune tolerance through allergen-specific immunotherapy or neutralization of IgE-mediated responses.