QuoteShellfish is the #1 cause of food allergy in adults in the Unites
States (1). A recent survey found that 1 in 50 Americans has shellfish allergy (2). Most shellfish species, provoking allergic reactions belong to the class crustacea, which includes shrimp, crab, crawfish and lobster with shrimp being the leading culprit. Since 1970 shrimp consumption has more than tripled and it is expected that allergy to shellfish will continue to be on the rise
QuoteTropomyosin is a highly conserved protein, with multiple isoforms that is found in both muscle and non-muscle cells of all species of vertebrates and invertebrates (Table 1). Allergenic tropomyosins are found in invertebrates such as crustaceans, arachnids
(house dust mites), insects (cockroaches) and mollusks (e.g. squid). but there is a lack of allergenic cross-reactivity between these tropomyosins and those from vertebrates such as bony fish, beef, pork or chicken, which are considered nonallergenic (8,10)
QuoteClinically relevant allergenic tropomyosin in crustaceans other than shrimp are found in lobster (Pan s 1, Hom a 1) (11-12), crab (Cha f 1) (13), squid (Tod p 1) (14), snail (Tur c 1) (15) and oyster (Cra g 1) (16). Those identified in other invertebrates are found in house dust mites (Der f 10, Der p 10) (17-18), and cockroaches (Per a 7, Bla g 7) (10,19-21). Immunological cross-reactivity has been demonstrated between crustaceans, cockroaches and House dust mites, suggesting that tropomyosin is an important crosssensitising panallergen (4,10). Some studies suggest that this cross-reactivity may be clinically relevant. Sensitization and allergic symptoms to ingested snails and shrimp have been reported following specific immunotherapy with dust mite (6) . IgE antibody 36 kD reactivity to shrimp among Orthodox Jews, unexposed to shellfish, was demonstrated and appeared to result from cross-reacting tropomyosin in subjects allergic to mite and/or cockroach (22).