Superoxide anion production by bronchoalveolar lavage cells in relation to cellular composition and lung function in sarcoidosis and chronic bronchitis

INTRODUCTION: Increased generation of superoxide anion (O2 –.) by bronchoalveolar lavage (BAL) cells has been reported in various inflammatory disorders. However, the clinical relevance of this phenomenon is unclear. OBJECTIVES: The aim of the study was to investigate whether production of O2–. is enhanced in smoking‑related chronic bronchitis and sarcoidosis, and to assess a relationship between O2–. generation and lung function impairment and changes in BAL cellular pattern. PATIENTS AND METHODS: Forty‑two patients with sarcoidosis, 24 smokers with chronic bronchitis, and 17 controls were examined. A number/percentage of BAL cells was calculated. Spontaneous and phorbol myristate acetate (PMA)-stimulated O2–. production was measured in BAL cells. Spirometry was performed. RESULTS: Patients with smoking‑related chronic bronchitis produced more O2 –. spontaneously (6.42 ±1.24 vs. 15.39 ±2.47 nmol/106 cells, P = 0.003) and after stimulation (3.73 ±1.32 vs. 14.76 ±2.79 nmol/106 cells; P = 0.001). PMA‑stimulated excess production correlated with the percentage of neutrophils (r = 0.66, P = 0.0005). In sarcoidosis, only spontaneous production of O2 –. was higher (vs. 18.07 ±2.49 nmol/106 cells, P = 0.004) and correlated with the percentage of BAL lymphocytes. There was no correlation between O2–. production and lung function parameters. CONCLUSIONS: Patients with smoking‑related chronic bronchitis produce more O2–., and this phenomenon is related to BAL neutrophils. In sarcoidosis, spontaneous release of O2–. from BAL cells is related to the extent of lymphocytic alveolitis. Higher O2–. generation did not impair lung function.