Microparticles and Bronchiolitis Obliterans Syndrome

The main long-term complication of lung transplantation is chronic lung allograft dysfunction (CLAD). Bronchiolitis obliterans syndrome (BOS) is the most frequent presentation of CLAD. BOS leads to a progressive loss of lung allograft function, with recurrence of dyspnea and airflow limitation. In some advanced cases, patients need a lung re transplantation. The mechanisms of BOS are not completely elucidated, and there are no early markers or specific treatment available for this condition. Microparticles (MPs) are submicron plasma membrane fragments released into the vascular compartment or the pericellular space in response to cell activation, injury or apoptosis. Broncho alveolar and circulating MPs may reflect cellular insults of the lung allografts. Therefore, MPs could be viewed either as biomarkers or as effectors of the chronic inflammatory or procoagulant processes leading to bronchiolitis obliterans syndrome. The investigators plan to include 60 patients before lung transplantation at our centre in Strasbourg (France). Follow-up will be requested at the base of usual care (spirometry, blood sampling, bronchoscopy with broncho-alveolar lavage \[BAL\]). The investigators will measure at one month, one, two and three year post transplantation, the total concentration of MPs in plasma and BAL and characterize their phenotype. The investigators objective is to demonstrate correlation between total MPs concentration in broncho-alveolar lavage fluid (BALF) and the occurrence of bronchiolitis obliterans syndrome at three years post lung transplantation.