Prophylaxis of intranasally induced pollen allergy in a BALB/C mouse model using a potential prebiotic β-1, 4 mannobiose.

Background: Dietary supplementation with unique prebiotic nondigestible carbohydrates has been shown to suppress allergy. In the present study, the prophylactic efficacy of a disaccharide β-1, 4 mannobiose (MNB) in a BALB/C mouse model of intranasally-induced pollen allergy was characterized.

Methods: Balb/c mice were pretreated with MNB orally and sensitized with pollen extract intraperitoneally and intranasally and challenged with histamine and crude pollen extract. Outcomes were measured as clinical signs, antibody isotypes, cytokine gene and protein expression patterns.

Results: The MNB-treated mice had lower sneezing frequency as compared to the positive control mice (P < 0.05). The low dose MNB-treated mice had less histamine (P < 0.05). However, the Cry j1 and Cry j 2-specific IgE, IgG, IgG1 and IgG2a antibody activity did not differ between groups (P > 0.05). The MNB-treated mice had increased IFN-γ (P < 0.05), and decreased IL-4 (P < 0.05). Mice in the high dose group had increased IL-10 (P < 0.05). However, TGF-β and IL-17 concentration did not differ between groups (P > 0.05). Both total and Cry j1 and Cry j 2-specific IgA were increased in the high dose group. Real-time RT-PCR analysis indicated that IL-4 and IL-17 mRNA expression were lower in MNB-treated mice (P < 0.05).

Conclusions: This work provides insights into using MNB as a potential prebiotic immunomodulator via decreased clinical signs, improved type1/type 2 balance, and IgA production, thus validating the potential use of MNB as a prophylactic prebiotic candidate to attenuate allergic response.