Mast cell-derived tumour necrosis factor is essential for allergic airway disease.

Mast cells are thought to contribute to allergic airway disease. However, the role of mast cell-produced mediators, such as tumour necrosis factor (TNF), for the development of allergic airway disease is unclear. In order to define the role of mast cells in acute allergic airway disease two strains of mast cell-deficient mice (Kit(W/Wv) and Kit(W-sh/W-sh)) were studied. Compared with their wild-type littermates, Kit(W/Wv) and Kit(W-sh/W-sh) mice developed significantly lower airway responsiveness to methacholine and less airway inflammation and goblet cell metaplasia, following sensitisation in the absence of adjuvant and airway challenge. Transfer of bone marrow-derived mast cells (BMMCs) from wild-type mice to Kit(W-sh/W-sh) mice reconstituted both airway responsiveness and inflammation to levels similar to those in sensitised and challenged wild-type mice. In contrast, sensitised Kit(W-sh/W-sh) mice reconstituted with BMMCs from TNF-deficient mice were still severely impaired in their ability to develop airway hyperresponsiveness, inflammation or goblet cell metaplasia following allergen challenge. The present results demonstrate the significance of mast cells in the development of airway disease and highlight the importance of mast cell-derived tumour necrosis factor in these responses.