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

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.