Inflammatory cell profiles and T-lymphocyte subsets in chronic obstructive pulmonary disease and severe persistent asthma

Summary Background Severe persistent asthma (SPA) and chronic obstructive pulmonary disease (COPD) are both associated with non‐reversible airflow limitation and airway neutrophilia. Objective To compare inflammatory cell profiles and T lymphocyte subsets between SPA and COPD patients with similar severity of airflow limitation. Methods Sputum induction and lung function tests were performed in 15 COPD patients aged (mean±SD) 68±8 years, ex‐smokers, mean forced expiratory volume in 1 s (FEV1) 45% of predicted (%pred) and 13 SPA aged 55±10 years, non‐smokers, mean FEV1 49%pred. All patients were on inhaled steroid treatment. Eight asthmatics exhibited irreversible airflow limitation. Differential cell count, metachromatic cell count and double immunocytochemistry for the analysis of T lymphocyte subsets were performed on sputum slides. Results COPD patients had increased sputum neutrophils in comparison with SPA (P