Role of Toll-like Receptor 2 in a Mouse Model of Allergic Rhinitis / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Mammalian Toll-like receptors (TLR) participate in innate immune responses to microbial pathogens. Recent interest has been focused on the concept that TLR-induced innate responses can modulate subsequent adaptive immune responses. The objective of this study is to determine whether TLR 2 stimulation in vivo would modulate subsequent allergic responses in an Aspergillus fumigatus (Af) murine model of allergic rhinitis (AR). MATERIALS AND METHOD: Mice were sensitized via intraperitoneal injection with Af antigen and alum, and received a series of three daily intranasal Af antigen challenge. A TLR 2 agonist, PamCys was administrated intranasally one day before sensitization or one day before the first intranasal allergen challenge. Adaptive immune profiles and response to Af challenge were assessed. RESULTS: PamCys decreased the allergen induced nasal recruitment of eosinophils and interleukin (IL)-5 in nasal lavage fluids compared with mice treated with no PamCys. Serologic data revealed that PamCys downregulated Af-specific IgE in the sera of PamCys-treated mice. In addition, spleen cells from the PamCys-treated mice displayed attenuated Af-specific IL-4 and IL-5, but increased interferon (IFN)- and immunosuppressive IL-10. CONCLUSION: The present study demonstrate that TLR 2 agonist decreases allergic responses in this AR model by shifting T helper 2 (Th2) biased immune parameters towards Th1 dominance.