title: Additive anti-allergic effects of anti-interleukin-33 and anti-Siglec-F treatments in a murine model of allergic asthma.
abstract: BACKGROUND
  Anti-interleukin-33 (anti-IL-33) and anti-Siglec-F antibodies have potent anti-allergic effects on murine allergic asthma and rhinitis and induce eosinophil apoptosis.
  
  
  OBJECTIVE
  We aimed to determine whether post-sensitization with anti-IL-33/anti-Siglec-F treatments exhibited more potent effects compared to individual treatments in a murine allergic asthma model.
  
  
  METHODS
  Twenty-five BALB/c mice were separated into five groups (n = 5): Group A (control), Group B (ovalbumin [OVA] challenge), Group C (OVA + anti-IL-33), Group D (OVA + anti-Siglec-F), and Group E (OVA + anti-IL-33 + anti-Siglec-F). Serum total/ OVA-specific IgE, bronchoalveolar lavage (BAL) inflammatory cells and cytokines (IL-4 and IL-5), histopathological lung properties, and airway hyperreactivity were compared.
  
  
  RESULTS
  Ovalbumin challenge induced strong immune and inflammatory responses with > 6-fold IgE level increases; 10- to 25-fold BAL eosinophil, neutrophil, and lymphocyte count increases; and > 1.5-fold IL-4 and IL-5 level increases (p < 0.05). Whereas anti-IL-33 reduced neutrophil counts, anti-Siglec-F and anti-IL-33/anti-Siglec-F reduced both eosinophil and neutrophil counts (p < 0.05). Individual treatments reduced OVA-mediated bronchiolar infiltration by 50% (p <0.05). Ovalbumin challenge increased airway hyperreactivity by 4-fold (Group B; 2000.0 ±671.8% increase in Penh) compared to controls (Group A; 445.7 ±33.5% increase in Penh) (p = 0.016). The anti-IL-33 (Group C: 1579.4 ±973.6% increase in Penh) and anti-Siglec-F (Group D: 930.4 ±236.5%) groups demonstrated significantly reduced hyperreactivity (p = 0.029). Anti-IL-33/anti-Siglec-F therapy showed synergism towards neutrophil counts, IL-5 concentrations, bronchial infiltration, and hyperreactivity (p < 0.05).
  
  
  CONCLUSIONS
  Combination treatment with anti-IL-33/anti-Siglec-F had more potent anti-allergic effects, reducing eosinophilic infiltration through their additive effects in a murine allergic asthma model.
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Tae Young
authors.initials: TY
authors.lastname: Jang
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Chang-Shin
authors.initials: CS
authors.lastname: Park
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Myung-Shin
authors.initials: MS
authors.lastname: Jeon
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Min-Jeong
authors.initials: MJ
authors.lastname: Heo
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Kwangmin
authors.initials: K
authors.lastname: Na
authors.affiliation: Inha University College of Medicine, Incheon, South Korea.
authors.forename: Young Hyo
authors.initials: YH
authors.lastname: Kim
keywords: Siglec-F; allergy; asthma; cytokines; interleukin-33