Allergen binding to specific IgE in the nasal mucosa of allergic patients

Background: Until now, it has not been possible to identify specific IgE locally in the airway mucosa. In this study we investigated the possibility of determining specific allergen binding locally in the nasal mucosa. Methods: Nasal mucosal biopsy specimens were taken from 11 patients with symptoms of an isolated grass pollen allergy, 10 patients with symptoms of perennial allergic rhinitis in response to house dust mite allergen, and 10 nonallergic control subjects. Sections of these biopsy specimens were stained by using commercially available biotinylated allergens (AlaSTAT, Diagnostic Products Corp.). Results: Staining with biotinylated grass pollen (GP1) demonstrated positive cells only in patients with grass pollen allergy. Biotinylated Dermatophagoides pteronyssinus (D1) only stained cells in patients with perennial allergy. Specific binding of allergen to cells of patients with allergy and the blocking experiments proved the method to be highly specific. Allergen-positive cells stained double with IgE, the high-affinity receptor for IgE (Fc@eRI), CD1, HLA-DR, tryptase, and chymase. Most allergen-positive cells proved to be mast cells. Conclusion: This immunohistochemical study shows the presence of specific IgE against grass pollen and house dust mite allergens locally on cells in the airway mucosa. (J Allergy Clin Immunol 1997;99:515-21.)