Primary target cells for influenza viruses are cells of the respiratory epithelium. In vitro studies with differentiated respiratory epithelial cells are possible, e.g. by using air-liquid interface cultures or explant cultures. The former culture system has been used to analyze the infection by human influenza viruses [6,7]. In the case of differentiated airway epithelial cells from pigs, infection studies with influenza viruses have been reported with explant cultures either from the trachea [8] or from different parts for the respiratory tract [9]. Here we report a new culture system for porcine differentiated respiratory epithelial cells, precision-cut lung slices (PCLS). This culture system has been used for various