Protective effect of excretory-secretory protein from adult Trichinella spiralis on ovalbumin-induced allergic rhinitis in mice

Abstract

To investigate the protective effect of excretory-secretory protein (AES) from adult Trichinella spiralis on ovalbumin (OVA)-induced allergic rhinitis in mice. Eighteen female BALB/c mice were randomly divided into three groups, including the blank control group (Group A), OVA-induced rhinitis group (Group B) and AES treatment group (Group C). Mice in Group A were given PBS. Mice in Group B were intraperitoneally injected with antigen adjuvant suspension for systemic sensitization, once every other day for seven times; then, local excitation was intranasally induced with 5% OVA solution once a day for seven times to establish a mouse model of allergic rhinitis. In addition to induction of allergic rhinitis, mice in Group C were given 25 μg AES at baseline sensitization and local excitation. Following the final challenge, mice were observed for 30 min in each group, and the behavioral score was evaluated. The serum levels of IFN-γ, IL-4, IL-5, IL-10 and TGF-β were determined using an enzyme-linked immunosorbent assay in mice, and the pathological changes of mouse nasal mucosa were observed under a microscope. There was a significant difference in the mouse behavioral scores among the three groups (F = 110.12, P < 0.01). The mouse behavioral score was significantly higher in Group B than in Group A (7.17 ± 0.75 vs. 1.33 ± 0.52, P < 0.01), and more remarkable pathological damages of mouse nasal mucosa were seen in Group B than in Group A, while the mouse behavioral score was significantly decreased in Group C than in Group B (P < 0.01), and the pathological damages of mouse nasal mucosa remarkably alleviated in Group C relative to Group B. There was a significant difference in serum IFN-γ level among the three groups (F = 7.50, P < 0.01) and the serum IFN-γ level in Group B was significantly lower than in group A and C (both P < 0.05). There were significant differences in serum IL-4 (F = 470.81, P < 0.01) and IL-5 levels (F =68.20, P < 0.01) among the three groups, and significantly greater serum IL-4 and IL-5 levels were detected in Group B than in Group A (P < 0.01), while significantly lower serum IL-4 and IL-5 levels were detected in Group C than in Group B (P < 0.01). There were significant differences in serum IL-10 (F = 174.91, P < 0.01) and TGF-β levels (F = 9.39, P < 0.01) among the three groups, and significantly greater serum IL-10 and TGF-β levels were seen in Group C than in Group B (both P < 0.05). T. spiralis AES has a remarkable protective activity against OVA-induced allergic rhinitis in mice.