Comparison of Antiallergic Effects of Pneumococcal Conjugate Vaccine and Pneumococcal Polysaccharide Vaccine in a Murine Model of Allergic Rhinitis

Objectives/HypothesisPneumococcal vaccines have been widely used, and Streptococcus pneumoniae has been suggested to be an effective therapeutic agent in allergic disease. ObjectivesThe present study was performed to evaluate the effects of pneumococcal polysaccharide vaccine (PV) and pneumococcal protein conjugate vaccine (PCV), and to examine differences between the vaccines in a murine model of allergic rhinitis. Study DesignIn vivo study using an animal model. SettingCatholic Research Institutes of Medical Science. MethodsAllergic rhinitis was induced in 40 BALB/c mice by intraperitoneal sensitization and intranasal challenge with Dermatophagoides farinae (Derf). The animals were divided into four groups: control, Derf, PV, and PCV. Interferon-, interleukin-13, and interleukin-10 levels in nasal lavage fluid and Derf-specific immunoglobulin E levels in serum were measured. The levels of T-bet, GATA-3, and Foxp3 mRNA expression in splenic mononuclear cells were determined. The number of CD4(+)CD25(+)Foxp3(+) regulatory T cells in splenic mononuclear cells was compared between groups by flow cytometry. ResultsAllergic symptom scores, T-bet and GATA-3 mRNA levels, serum Derf-specific immunoglobulin E levels, and tissue eosinophil counts were lower in the PV and PCV groups than the Derf group (P<0.05). The regulatory T (Treg) cell indicators, Foxp3 mRNA, and percentages of CD4(+)CD25(+)Foxp3(+) T cells were increased in the PV and PCV groups (P<0.05). Conclusion and Clinical RelevanceBoth PV and PCV suppressed the allergen-specific T helper 2 response and induced regulatory T cells in a murine model of allergic rhinitis. However, PV and PCV may activate Treg cells via different mechanisms. Level of EvidenceN/A. Laryngoscope, 123:2371-2377, 2013