Effect of transglutaminase cross-linking on the allergenicity of tofu based on a BALB/c mouse model

Abstract

Soybean products are limited in terms of safe consumption because of the sensitization of raw materials. In this study, the allergenicity of cross-linked tofu with microbial transglutaminase (MTG) was evaluated on the basis of a BALB/c mouse model. The mice were randomly divided into five groups. Cholera toxin was used as an adjuvant to sensitize the mice through intragastric administration, and tofu was given orally to investigate its sensitization effect on the mice. The allergy symptoms, body temperature, and weight of the mice were detected. The immunoglobulin E (IgE), immunoglobulin G (IgG), and spleen cytokines of the mice were determined through an enzyme-linked immunosorbent assay. The regulation of the differentiation balance of the different subsets of splenic T lymphocyte (Th1, Th2) and regulatory T cells (Tregs) in the mice was measured through flow cytometry. Results showed that the mice administered with MTG-cross-linked tofu had fewer allergic symptoms compared with those of the control group. The concentrations of serum-specific IgE and IgG, plasma histamine, and mast cell protease 1 (mMCP-1) significantly decreased. The Th2-related cytokine levels reduced, and the IFN-γ levels increased. The proportion of Th2 cells decreased, and the proportion of CD4⁺CD25⁺Foxp⁺ Tregs increased as the percentage of Th1 cells increased. Therefore, the sensitization of enzymatic cross-linked tofu decreased.