VitD3 given intranasally reduced lung inflammation
We next wanted to analyze the effect of intranasal treatment of Vitamin D3 in the airways in a murine model of airway tolerance (Fig 3a). To this aim, we treated mice intranasally with VitD3 and looked at airways inflammation (Fig 3b) . Here we found that allergen challenge, without allergen sensitization, was accompanied by induction of local inflammation (Fig 3a,b). By contrast, intranasal VitD3 treatment, reduced lung inflammation (Fig 3b). We then asked if Eosinophils in bronchoalveolar lavage fluid were involved in regulating airway tolerance after allergen challenges. Here we found that allergen challenge, without allergen sensitization, was accompanied by induction of local inflammation and induced eosinophils in BALF (Fig 3c).By contrast, intranasal VitD3 treatment, reduced lung inflammation(Fig 3c). Alltogether these data indicate an anti-inflammatory effect of VitD3 given intranasally in a model of airway tolerance.