Mutschler and colleagues, for the first time ever, showed the presence of MPs, derived from platelet, in pulmonary air-liquid interfaces in sedated pigs [25] . Recent investigation conducted in broncho-alveolar liquid fluid (BALF) has provided the characterization of intra-alveolar procoagulant MPs in patients with acute respiratory distress syndrome (ARDS) and hydrostatic pulmonary oedema. Intra-alveolar MPs from ARDS patients contain high levels of tissue factor, show an highly procoagulant activity, and are likely contribute to intra-alveolar fibrin formation, a critical pathogenic feature of acute lung injury [26] . To the best of our knowledge, no studies have been conducted to elucidate about the presence and role of MPs in other lung diseases. Since cellular activation and apoptosis, the main sources of MPs, are features of neutrophils in the CF airways, we have undertaken a study for the identification and characterization of MPs in the sputa of CF patients.