The Chemotactic Behavior of Eosinophils in Patients With Chronic Rhinosinusitis

Objective To characterize peripheral eosinophil migration in patients with chronic rhinosinusitis in the presence of nasal mucin and nasal tissue extracts. Study Design Prospective, controlled, ex‐vivo. Methods Peripheral blood eosinophils, nasal mucin, and nasal tissue were harvested at the time of sinus surgery in 10 patients, as well as obtained in 10 healthy control subjects. Extracts were prepared from nasal mucin and nasal tissue. A modified Boyden chamber was used to study eosinophil migration from both patients and healthy control subjects in the presence of both extracts. Results Patients with chronic rhinosinusitis and all healthy control subjects demonstrated a concentration‐dependent increased migration of eosinophils in the presence of both nasal mucin and nasal tissue extracts. The percentage of migration was consistently higher for eosinophils from patients with chronic rhinosinusitis compared with control subjects. The difference attained statistical significance in the presence of 50% tissue extract (median percentage of migration, 23.3% vs. 7.8% [P = .033]). Conclusions Nasal mucin and nasal tissue in chronic rhinosinusitis contains chemoattractants, which can induce active eosinophil migration. The eosinophil migration from patients with chronic rhinosinusitis was consistently higher compared with eosinophils from healthy control subjects. Because the eosinophils were obtained from the peripheral blood, this finding suggests activation of eosinophils in the systemic circulation in chronic rhinosinusitis.