Th2 dominance in nasal mucosa in patients with Wegener’s granulomatosis

Wegener's granulomatosis initially affects upper respiratory tract organs including the nasal mucosa in more than 90% of patients. The inflammation is typically granulomatous with associated vasculitis. T lymphocytes are usually a prominent component of the leucocyte infiltrate. Previous studies using peripheral blood T cells have implicated IFN‐γ rich Th1‐type responses. This study addressed the cytokine milieu in nasal mucosa from 10 patients with active Wegener's granulomatosis using immunohistochemistry. Increased levels of CD3+ T cells and eosinophils were present compared with normal and disease controls. There was increased expression of IL‐4, down‐regulation of IL‐2 and no detectable IFN‐γ. There was increased expression of the chemokine receptor CCR3 by infiltrating cells, consistent with an IL‐4 dominant, Th2‐biased response. In contrast, renal biopsy tissue from 10 patients with active Wegener's granulomatosis showed expression of IL‐2 and IL‐4. The Th2‐type environment within nasal mucosa, often the initial site of disease activity in Wegener's, is consistent with a local allergic response in these patients.