Nasal provocation with a single dose of allergen induces a typical nasal allergic inflammatory response that resolves spontaneously
The nasal challenge with a single dose of grass pollen allergen induced typical allergic symptoms in all patients that resolved spontaneously. Clinical scores were highest 15 minutes after the administration of the allergen, falling progressively to pre-challenge levels by 48 hrs after the challenge (Fig. 1, A ). A modest nasal obstruction was the longest lasting symptom (Fig. S1). No clinical response was observed after the diluent challenge. Total nasal lavage inflammatory cells and nasal lavage protein levels peaked at 1 hr after the allergen challenge and returned progressively to pre-challenge values within 72 hrs (Fig. 1, B and C ). No significant kinetics were observed after diluent challenges.