Extraction and Purification of Tropomyosin From Crabs Scylla olivacea and Charybdis ferriatus: Assessment of Allergenicity and Sensitizing Capacity Using Animal Experimental Model.

Tropomyosin is a significant allergen found in invertebrates and is recognized as one of the primary triggers of food-induced anaphylaxis. Though many researchers have done the characterization of allergic tropomyosin, a comparative analysis of the allergenicity of vertebrate (porcine) and invertebrate (crab) tropomyosin is still lacking. The present study aims to study the differences in IgE, tropomyosin-specific IgE, and histamine levels between vertebrate (porcine) and invertebrate tropomyosin (crab) using an animal experimental model. Tropomyosin was extracted from two selected crabs, marine water (Scylla olivacea) and freshwater (Charybdis ferriatus). A high level of systemic anaphylactic reactions was observed in the mice groups treated with crab tropomyosin. In addition, high levels of IgE, tropomyosin-specific IgE, and histamine levels as revealed by ELISA (Enzyme-Linked Immunosorbent Assay) analysis. Histopathological examination exhibited changes in the liver and gastrointestinal regions of the mice groups treated with crab tropomyosin. The variations in the amounts of transcription factors like T-bet, GATA-3, and Foxp3 were also evaluated through gene expression analysis. The presence of GATA-3' transcription factor was also identified in the spleen of mice treated with crab tropomyosin. This study helps for the better diagnosis and treatment of food allergies, especially shellfish allergies.