Effects of Nasal Instillation of Staphylococcal Enterotoxin B on Allergic Inflammation in Mice

Abstract

Background and Objectives The role of Staphylococcus aureus enterotoxin B (SEB) in allergic rhinitis remains controversial. We used a mouse model of airway allergy to determine the effects of nasal instillation of SEB on allergic inflammation. Materials and Method BALB/c mice were intranasally sensitized with compound of Aspergillus melleus proteinase (AMp) and ovalbumin (ova) in the presence (group 3) or absence of SEB (group 2). Control mice were intranasally sensitized with either phosphate buffered saline (PBS)(group 1) or SEB (group 4) alone. The production of serum antigen-specific antibodies and total IgE, and concentrations of cytokines including interleukin-4 (IL-4), IL-5, interferon- (IFN-) in nasal lavage fluid (NLF) and broncoalveolar lavage fluid (BALF) were compared among the groups. Pathologic studies for eosinophilic infiltrations in the nasal mucosa and peribronchial area were also conducted. Results Serum ova-specific immunoglobulin E (IgE) & immunoglobulin G1 (IgG1) were significantly increased in group 2 and 3 compared to group 1. The concentrations of IL-4 in BALF were significantly increased in group 2, 3, and 4 compared to group 1. The concentrations of IL-5 in BALF and NLF were significantly increased in Group 2, 3, and 4 compared to group 1. The concentrations of IFN- were significantly increased in group 3 and 4 compared to group 2 although there was no significant difference among the groups in NLF. Group 2 demonstrates increased infiltration of eosinophils in the nasal mucosa and peribronchial area compared to group 3 and 4. Conclusion These results suggest that the nasal exposure to SEB did not aggravate inflammation in allergic mice.