title: The Role of IL-17 in a Lipopolysaccharide-Induced Rhinitis Model.
abstract: OBJECTIVE
  Lipopolysaccharide (LPS) is a cell wall component of Gram-negative bacteria and important for pro-inflammatory mediators. This study aimed to establish a rhinitis model using ovalbumin (OVA) and LPS in order to evaluate the role of interleukin (IL)-17 in the pathogenesis of an LPS-induced non-eosionophilic rhinitis model.
  
  
  METHODS
  Mice were divided into 4 groups and each group consisted of 10 mice (negative control group, allergic rhinitis model group, 1-μg LPS treatment group, and 10-μg LPS treatment group). BALB/c mice were sensitized with OVA and 1 or 10 μg of LPS, and challenged intranasally with OVA. Multiple parameters of rhinitis were also evaluated to establish the LPS-induced rhinitis model. IL-17 knockout mice were used to check if the LPS-induced rhinitis model were dependent on IL-17. Eosinophil and neutrophil infiltration, and mRNA and protein expression profiles of cytokine in nasal mucosa or spleen cell culture were evaluated using molecular, biochemical, histopathological, and immunohistological methods.
  
  
  RESULTS
  In the LPS-induced rhinitis model, neutrophil infiltration increased in the nasal mucosa, and systemic and nasal IL-17 and interferon-gamma (IFN-γ) levels also increased as compared with the OVA-induced allergic rhinitis model. These findings were LPS-dose-dependent. In IL-17 knockout mice, those phenotypes (neutrophil infiltration, IL-17, and IFN-γ) were reversed, showing IL-17 dependency of LPS-induced rhinitis. The expression of vascular endothelial growth factor (VEGF), an important mediator for inflammation and angiogenesis, decreased in IL-17 knockout mice, showing the relationship between IL-17 and VEGF.
  
  
  CONCLUSIONS
  This study established an LPS-induced rhinitis model dependent on IL-17, characterized by neutrophil infiltration and increased expression of IL-17.
authors.affiliation: Department of Otorhinolaryngology, Dankook University College of Medicine, Cheonan, Korea.|Department of Premedical Course, Dankook University College of Medicine, Cheonan, Korea.
authors.forename: Jun Sang
authors.initials: JS
authors.lastname: Bae
authors.affiliation: Department of Otorhinolaryngology, Dankook University College of Medicine, Cheonan, Korea.
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology, Dankook University College of Medicine, Cheonan, Korea.
authors.forename: Eun Hee
authors.initials: EH
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology, Dankook University College of Medicine, Cheonan, Korea. jihunmo@gmail.com.
authors.forename: Ji Hun
authors.initials: JH
authors.lastname: Mo
keywords: Rhinitis; interleukin-17; lipopolysaccharide; vascular endothelial growth factor