Low-dose allergen challenge (LDAC) is a potentially useful tool for studying the capacity of allergens to induce airway inflammation and remodeling in atopic subjects. To evaluate markers of inflammation (eosinophils) and remodeling (fibronectin, vascular endothelial growth factor [VEGF]) following repeated LDAC in nonasthmatic subjects with allergic rhinitis compared with mild allergic asthmatic subjects. Fourteen nonasthmatic subjects with allergic rhinitis and 11 stable mild allergic asthmatic subjects underwent spirometry and methacholine challenge, and blood and induced sputum (IS) with differential cell counts were obtained. Each subject underwent LDAC on 4 consecutive mornings with a relevant allergen. Spirometry, methacholine challenge, and blood and IS samplings were repeated 6 h after the second and fourth LDAC and 1 week later. Sputum eosinophil cationic protein, fibronectin, and VEGF were measured using radioimmunoassay and enzyme-linked immunosorbent assay.