Characterization of systemic allergenicity of tropomyosin from shrimp (Macrobrachium nipponense) and anaphylactic reactions in digestive tract

Abstract

BACKGROUND Tropomyosin (TM) is the major allergen of crustaceans. The allergenicity of TM from Macrobrachium nipponense (MnTM) and the anaphylactic reaction in the digestive tract are still unclear. The aim of this study was to evaluate the allergenicity of MnTM and the anaphylactic reaction in the digestive tract. RESULTS Serum IgE and IgG1 binding ability in the TM group were significantly higher than those in the PBS and CT groups (P < 0.01) and CP group (P < 0.05), while serum IgG and IgG2a binding ability showed no obvious difference between the four groups (P > 0.05). The levels of cytokines IL‐4, IL‐5 and IL‐13 in TM and CP groups were significantly higher than those in PBS and CT groups. Histamine and β‐hexosaminidase in the TM and CP groups from basophil cell models were significantly higher than those in the PBS group. The highest mRNA expression of IL‐4 and IL‐13 was in the jejunum from TM‐sensitized mice. Histopathological analysis showed that more immune cells infiltrated into the jejunum than the duodenum and ileum from the TM‐sensitized mice. CONCLUSIONS MnTM could promote an allergic response in mice and lead to degranulation in basophil cells. The jejunum was more easily affected by MnTM than duodenum and ileum, and the jejunum may be the major site of allergic response in the digestive tract. © 2020 Society of Chemical Industry

Digestion-Resistant Linear Epitopes as Dominant Contributors to Strong Allergenicity of Tropomyosin in Antarctic Krill (Euphausia superba)

“…31 Therefore, the degranulation of mast cells and the levels of histamine and mMCP-1 in plasma are important markers of anaphylaxis in mice. 32 The degranulation of mast cells in toluidine blue-stained spleen sections of 6 groups of mice was observed and counted under the optical microscope (Figure 2A,B). The splenic mast cells of mice in the NS groups were dark blue spheres with a complete structure.…”

“…When an allergen re-enters the body, the activated specific IgE receptors (FcεRI) on the surface of mast cells will be cross-linked with it, leading to the degranulation of mast cells and the release of histamine, mMCP-1, and other mediators . Therefore, the degranulation of mast cells and the levels of histamine and mMCP-1 in plasma are important markers of anaphylaxis in mice . The degranulation of mast cells in toluidine blue-stained spleen sections of 6 groups of mice was observed and counted under the optical microscope (Figure A,B).…”

An overview of tropomyosin as an important seafood allergen: Structure, cross‐reactivity, epitopes, allergenicity, and processing modifications

“…As a continuous coiled‐coil parallel homodimer, TM follows a repetitive “abcdefg” heptamer pattern (Figure 1a). The entire structure of TM is made up of about 40 of these heptad repeats from “a” to “g,” where sites “a” and “d” are mostly occupied by nonpolar residues, and sites “b,” “c,” “e,” “f,” and “g” are mostly occupied by polar or ionic residues (James et al., 2018; Xie et al., 2020). Also, the acid residues are generally located at “e,” and the alkaline residues are located at “g.” The electrostatic interaction between acid and alkaline residues is beneficial to the stability of the coils.…”

Molecular Characterization and Cross-Allergenicity of Tropomyosin from Freshwater Crustaceans

“…Similarly, monoallergies to either freshwater or marine or estuarine crustaceans have been clinically described. 3,4 Currently, some freshwater crustacean species are reported to cause food allergies, including giant river prawn (Macrobrachium rosenbergii), 5,6 riceland prawn (Macrobrachium lanchesteri), 3,7 oriental river prawn (Macrobrachium nipponense), 8 Siberian prawn (Exopalaemon modestus), 9 red swamp crayfish (Procambarus clarkii), 10−13 and narrow-clawed crayfish (Pontastacus leptodactylus). 14 In Thailand, four species of freshwater crustaceans are commonly consumed: giant river prawn (M. rosenbergii), riceland prawn (M. lanchesteri), red swamp crayfish (P. clarkii), and red claw crayfish (C. quadricarinatus).…”

“…Currently, some freshwater crustacean species are reported to cause food allergies, including giant river prawn (Macrobrachium rosenbergii), , riceland prawn (Macrobrachium lanchesteri), , oriental river prawn (Macrobrachium nipponense), Siberian prawn (Exopalaemon modestus), red swamp crayfish (Procambarus clarkii), − and narrow-clawed crayfish (Pontastacus leptodactylus) . In Thailand, four species of freshwater crustaceans are commonly consumed: giant river prawn (M.…”