Pulmonary surfactant impairment in lung transplant recipients

The pulmonary surfactant system is altered following lung transplantation (LTx). We recently found that surface activity was significantly decreased in LTx patients compared to healthy subjects. Surface tension reducing capacity is caused by the large surfactant aggregate subfraction (LA). In contrast, small aggregates have poor surface activity and represent the metabolic product of LA. Furthermore, protein inhibiton is a known cause of impaired surfactant activity. Therefore, the aim of this study was to investigate wether decreased surfactant activity after LTx was due to changes in LA´s or inhibition by proteins.