Soybean glycinin- and β-conglycinin-induced intestinal immune responses in a murine model of allergy

Glycinin and β-conglycinin are major soybean allergens involved in food hypersensitivity. The study was aimed to investigate the soybean protein-induced intestinal immune responses and its possible mechanism. Balb/c mice were sensitised intragastrically with glycinin and β-conglycinin without an adjuvant for five weeks. Results showed that the sensitised mice displayed diarrhoea symptoms and jejunal morphological changes, including decreased villous height and thickened crypt depth. Both the histamine and immunoglobulin A levels in jejunum were increased in soybean allergen-sensitised mice. Moreover, the number of IgA+B cells and CD4+T cells in the jejunal lamina propria of sensitised mice were significantly increased. The expression levels of interleukin-4 and interferon-γ were increased, whereas the levels of IL-10 and transforming growth factor-β (TGF-β) were decreased in the jejunum mucosa. In conclusion, glycinin and β-conglycinin induce a mixed Th1/Th2 immune response. The suppression of IL-10 and TGF-β may play important roles in the development of intestinal allergic reactions.